Table of Content

10 June 2024, Volume 43 Issue 6

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Productivity and carbon budget dynamics of forests under different topographic conditions on Tibetan Plateau.

DOU Jiahui, LIANG Yu, HUAI Baojuan, WU Miaomiao, LIU Bo, MA Tianxiao, WANG Yao

2024, 43(6):  1521-1530.  doi:10.13292/j.1000-4890.202406.048

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Topography is a main environmental factor affecting the spatial distribution of productivity and carbon budget of forests. Tibetan Plateau is an ideal place to study the effects of topography on the pattern of forest carbon budget due to its complex topography and abundant forest types. However, due to the difficulty of field investigation in the Tibetan Plateau forest area, there is a lack of comprehensive understanding of the impacts of topographic factors on forest carbon budget dynamics on Tibetan Plateau. Therefore, this study aimed to simulate the spatiotemporal variations of forest carbon budget on the Tibetan Plateau and analyze the differences of forest productivity and carbon budget dynamics under different topographic conditions. The temporal and spatial dynamics of gross primary productivity (GPP), above-ground biomass (AGB), and net ecosystem exchange (NEE) in middle-high altitude forests were simulated by using process-based model (FORMIND) under different topographic conditions, and the model applicability in the study area and the accuracy of the simulation results were verified. We analyzed current (2000-2014) and future (2015-2040) productivity and carbon budget. Furthermore, we quantified the relative importance of topographic factors on GPP, AGB, and NEE using XGBoost machine learning algorithm. The results showed that  GPP (6.73±0.53 t C·hm^-2·a^-1), AGB (167.23±17.45 t·hm^-2), and NEE (0.32±0.12 t C·hm^-2·a^-1) simulated by FORMIND model were basically consistent with the data of plot survey and remote sensing observation, which verified the accuracy of the simulation results. In the future (2014-2040), there is an obvious increase in AGB, a slight increase in GPP, and a decreased but positive value in NEE, which indicated that forests would be carbon sinks. AGB and GPP were negatively correlated with elevation. AGB and NEE were weakly positively correlated with slope. The  GPP, AGB, and NEE of forests on sunny slope were higher than those on shady slope. Compared with slope and aspect, elevation had a greater effect on productivity and carbon budget dynamics of forests on the Tibetan Plateau. Our results are helpful to further understand the spatial distribution of forest productivity and carbon budget on the Tibetan Plateau.





Soil enzyme stoichiometric characteristics of natural forest and plantation of subalpine spruce in western Sichuan.

GAO Haoying, FU Shuangjia, SONG Shiyu, Samra Batool, WANG Lixia

2024, 43(6):  1531-1539.  doi:10.13292/j.1000-4890.202406.020

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Soil enzymes and stoichiometry are key indicators for soil nutrient availability and microbial nutrient limitation. However, the variations and key driving factors of soil enzyme activities and stoichiometric ratios after the conversion of subalpine natural forests to plantations in western Sichuan remain unclear. In this study, we measured soil physicochemical properties and enzyme activities in a natural secondary forest and a plantation of subalpine spruce in western Sichuan. The results showed that: (1) Soil C∶N ratio of natural forest was significantly lower than that of plantation (P<0.05), while soil C∶P and N∶P ratios were significantly higher than that of plantation (P<0.05). (2) The C∶N_EEA and C∶P_EEA of natural forest were significantly higher than that of plantation, while N∶P_EEA was significantly lower than that of plantation (P<0.01). The carbon quality indices (CQI1 and CQI2) of plantation were significantly higher than natural forest (P<0.05), while vector length and vector angle were significantly lower than natural forest (P<0.01). (3) Soil microorganisms were limited by C and P in the natural forest, but by N in the plantation. (4) The results of redundancy analysis showed that soil total N was the main factor affecting the enzyme stoichiometric ratio. Our results suggest that the N requirements of microorganisms should be fully considered in soil nutrient management of plantations in this region.





Effects of elevation and forest gap on soil nematode communities in Abies georgei var. smithii forest in the Sejila Mountains.

GAO Wanwan, HOU Lei, LU Jie, REN Yihua

2024, 43(6):  1540-1548.  doi:10.13292/j.1000-4890.202406.016

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To understand the responses of soil nematodes in alpine forests of the Tibet Plateau to altitude and forest gaps, differences in soil nematode communities among elevations and between forest and forest gaps in an Abies georgei var. smithii forest of the Sejila Mountains in southeast Tibet were analyzed using high-throughput sequencing techniques. The results showed that soil nematode diversity increased with decreasing altitude, while nematode diversity was slightly higher in forest gaps than within forests without statistical significance at the same elevation. Enoplea and Triplonchida were the most dominant taxa at mid-elevation (4292 m). The soil nematode community structure varied significantly with the altitude, but exhibited similar between the gap and the forest.  Soil water content, phosphorus content (including total and available phosphorus), and nickel content were the major factors affecting soil nematode diversity, while soil heavy metal and nutrient changes induced by forest gaps were the key factors affecting soil nematode community structure.





Validation of forest landscape model in forest survey data-poor regions: An example of simulating forest landscape dynamics on the Qinghai-Tibet Plateau with the LANDIS PRO model.

ZHANG Pengchao, LIANG Yu, WU Miaomiao, LIU Bo, MA Tianxiao

2024, 43(6):  1549-1557.  doi:10.13292/j.1000-4890.202406.019

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The forest landscape model (FLM) has been recognized as a crucial tool for simulating the dynamics of forest landscapes. The efficacy of predictions of the model will determine its width and depth of application in forest management. The limited availability of survey data is a main constraint on model validation. Choosing appropriate methods to compensate for data gaps and addressing the challenge of model validation in data-scarce regions can promote the wider application of FLM. In this study, a framework for model validation was established based on multi-source data and spatiotemporal substitution in regions with limited forest survey data. We used the LANDIS PRO forest landscape model to simulate the future forest landscape dynamics of the Qinghai-Tibet Plateau. The specific validation framework was as follows. First, the model parameters were calibrated using forest survey data. Then, the short-term model results were validated using multiple sources of data (forest survey data, remote sensing products, and existing research results). Finally, both spatiotemporal substitution and previous research results were used to validate the long-term results. The validation results showed that the initial simulation results accurately represented the real forest attributes. The short-term simulation results of LANDIS PRO based on multiple indicators were relatively consistent with the validated data at both plot and landscape scales (RMSE<80 t·hm^-2, SD<80 t·hm^-2, R²=0.81). The long-term dynamic characteristics of forests were consistent with previous research, with the model predictions of forest composition, structure, and succession being consistent with the growth trajectory of native forest in the region. This suggests that the established validation framework of forest landscape model under the conditions of the lack of forest resource data can effectively validate the simulation results of forest landscapes.





Changes in stable carbon isotope composition and intrinsic water use efficiency of plants along an altitude gradient in the Meili Snow Mountain.

CAI Jinfeng, XUE Zijing, HUANG Kangxiang, ZHANG Yuan, YUAN Bosen, REN Jiusheng, SHI Xiaoyi, PU Tao, SHI Fuxi

2024, 43(6):  1558-1565.  doi:10.13292/j.1000-4890.202406.027

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To explore the effects of altitude on stable carbon isotope composition (δ¹³C_p) and intrinsic water use efficiency (iWUE) of different functional plants at different altitudes (i.e., 2200, 2500, 2700, 3000, 3200 and 4200 m) on the eastern slope of the Meili Snow Mountain, Southwest China, we examined the variations in δ¹³C_p and iWUE of plants with different photosynthetic pathways (C₃ and Crassulacean acid metabolism, CAM) and different life forms in C₃ plants (shrubs, broad-leaved trees, and coniferous trees) along the altitude gradient. Results showed that: (1) The δ¹³C_p values of C₃ plants ranged from -26.72‰ to -31.67‰, with an average value of -29.12‰. δ¹³C_p values of CAM plants ranged from -13.24‰ to -14.59‰, with an average value of -13.77‰. (2) The δ¹³C_p and iWUE values of CAM plants were significantly higher than those of C₃ plants, and the δ¹³C_p and iWUE values for different life forms in C₃ plants varied in the order of shrubs>broad-leaved trees>coniferous trees; (3) Below 3200 m, the δ¹³C_p and iWUE values of trees and shrubs decreased with increasing altitude, which was influenced by soil moisture. Above 3200 m, however, the δ¹³C_p and iWUE values of shrubs increased with increasing altitude, which was influenced by temperature. Overall, the response of water use efficiency of species from different functional groups in the Meili Snow Mountains to the variations of altitude may reflect the different adaptability of different plant species to alpine climate.





Spatial and temporal variations of the potential habitat of Asterothamnus centraliasiaticus on the Qinghai-Tibet Plateau under climate change.

LI Zhengsheng, MA Yushou, LI Youxin, LIU Ying, WANG Yanlong, WANG Xinyou

2024, 43(6):  1566-1575.  doi:10.13291/j.1000-4890.202406.025

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The Qinghai-Tibet Plateau is highly ecologically sensitive and vulnerable to global climate change. Predicting the spatial and temporal variations of the habitats of dominant species is crucial for ecological restoration and the formulation of conservation measures. Using the Maxent model, we combined distribution records and bioclimatic variables to simulate and predict the potential distribution areas of Asterothamnus centraliasiaticus, a dominant species in the temperate desert steppe of the Qinghai-Tibet Plateau, under different climatic scenarios. Our results showed that temperature variables were the primary climatic constraints affecting the distribution of A. centraliasiaticus, while precipitation variables had a secondary impact. The suitable temperature range for growth was 16.5-38.5 ℃, with precipitation in the warmest season varying from 55.0-1885.5 mm. Population of A. centraliasiaticus has been expanding from the mid-Holocene to the present, mainly in the arid and semi-arid areas along the northeastern margin of the Qinghai-Tibet Plateau. The total habitat area of A. centraliasiaticus is predicted to decline in the future, particularly in the moderately and highly suitable habitats. Furthermore, the population is predicted to migrate gradually eastwards. Overall, our study highlights the challenges faced by A. centraliasiaticus in terms of survival and reproduction under global climate change. We recommend establishing relevant policies and regulations based on its migration trend to ensure the continuity of its habitat and develop effective conservation measures on the Qinghai-Tibet Plateau.





Vegetation changes and driving factors in the Qilian Mountains during 1982-2022.

YANG Xin, XUE Huazhu, DONG Guotao, LIU Donghao, LI Zichuang

2024, 43(6):  1576-1586.  doi:10.13292/j.1000-4890.202406.015

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Qilian Mountains is an important ecological security barrier in northwest China. In order to reveal the status and driving mechanism of vegetation cover change in the Qilian Mountains, we obtained 1 km NDVI data from 1982-2022 by integrating GIMMS NDVI and MODIS NDVI, combined with multi-temporal land use, vegetation, geomorphic and meteorological data. Using Theil-Sen trend analysis, Mann-Kendall significance test, and optimal parameter geographic detector model, we analyzed the spatio-temporal variation and spatial heterogeneity of NDVI in the Qilian Mountains. The results showed that vegetation coverage was relatively low in the northern region of Qilian Mountains and relatively high in the southeastern region. From 1982 to 2022, vegetation coverage in Qilian Mountains significantly increased, but appeared a trend of vegetation degradation in the past decade. The average annual precipitation and humidity index were the main driving factors affecting vegetation coverage, with explanatory power of 69.6% and 61.9%, respectively. The interaction between annual precipitation and elevation had a significant impact on the distribution of NDVI. This study revealed the types or ranges of driving factors that promote NDVI growth, providing scientific basis for better understanding the driving factors of NDVI changes in vegetation in the Qilian Mountains.





Phenophase variations and influencing factors of Salix matsudana in Xizang from 2001 to 2022.

DU Jun, HUANG Zhicheng, SONAM Targye, BAI Yuxuan, WANG Ting

2024, 43(6):  1587-1595.  doi:10.13292/j.1000-4890.202406.022

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To reveal the spatial-temporal pattern of Salis matsudana phenology in response to climate change on Tibetan Plateau, both the phenophase data and daily meteorological data at Tsedang, Xigazê, and Nyingchi from 2001 to 2022 were analyzed to identify the change trend of phenophase of S. matsudana and its influencing factors. The phenophase data included leaf bud enlargement date (LED), first leaf unfolding date (LUD), first flowering date (FFD), end of leaf coloring date (LCD), and end of leaf fall date (LFD). The daily meteorological factors included the daily average temperature (T_m), maximum temperature (T_max), minimum temperature (T_min), temperature daily range (TDR), relative humidity (RH), precipitation (P_r), sunshine duration (S), and accumulated temperature above 0 ℃ (∑T₀). These data were analyzed with linear regression, Pearson correlation coefficient, and stepwise regression methods. The results showed that: (1) Spatially, the earliest spring phenophase (LED, LUD, and FFD) of S. matsudana occurred in Nyingchi while the latest occurred in Xigazê. However, this phenomenon was exactly opposite for the autumn phenophase (LCD and LFD). The length of growth season (LOS) ranged from 238 to 268 days, with the largest value in Nyingchi and the smallest in Xigazê. (2) On the temporal scale, all phenophases of S. matsudana delayed in Xigazê and Tsedang, but only the autumn phenophases of S. matsudana delayed in Nyingchi in the past 22 years. The LOS of S. matsudana was prolonged in Xigazê and Nyingchi at growth rates of 11.90 and 6.12 d·10 a^-1, respectively. In contrast, the LOS of S. matsudana was shortened at a rate of 4.50 d·10 a^-1 in Tsedang. (3) Increasing trends of T_m during the growing season of S. matsudana were found in Xizang, but the increasing trends were different for T_max and T_min. The increased TDR and S and decreased P_r occurred in Tsedang and Xigazê, but this situation was opposite in Nyingchi. ∑T₀ increased significantly in Xigazê and Nyingchi, but decreased significantly in Tsedang. (4) Air temperature was the leading meteorological factor influencing spring phenophases. In contrast, precipitation only exerted the greatest influence on the LCD of S. matsudana at Tsedang and Nyingchi, and the LFD at Tsedang. The monsoon index (MI) was only significantly correlated with the LED and FFD of S. matsudana at Tsedang station, but did not correlate with the phenophases at other two stations. Significant correlations between MI and T_m, P_r and S occurred ubiquitously at all stations over the Tibetan Plateau in July, while MI showed a significant negative correlation with S in August. Although these meteorological factors were not the main factors affecting phenophases, they would also play an indirect role.





Diversity of epilithic mosses in Sejila Mountain and soil formation and water holding capacity of dominant species.

DONG Ying, ZHANG Shouchao, ZHUO Gabayong, PAN Gang, WANG Ruihong

2024, 43(6):  1596-1603.  doi:10.13292/j.1000-4890.202406.043

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We investigated the diversity of epilithic mosses in Sejila Mountain of Nyingchi City, Tibet, and evaluated the biomass, soil formation capacity, and water holding capacity of three dominant species. The results showed that there were 8 families, 12 genera and 16 species of epilithic mosses. Hypnaceae, Thuidiaceae, and Dicranaceae were the dominant families, while Ptilium crista-castrensis, Dicranum fuscescens, and Actinothuidium hookeri were the dominant species. Biomass of dominant species of epilithic mosses was 110.7-763.6 g·m^-2, with a soil formation capacity of 234.9-9063.3 g·m^-2, a maximum water holding capacity of 2164.5-8514.5 g·m^-2, a maximum water holding rate of 169%-400%, a natural water holding capacity of 1984.74-6764.5 g·m^-2, and a natural water holding rate of 95%-318%. Therefore, the epilithic mosses in Sejila Mountain play an important role in soil formation and water holding, which is of great significance for soil erosion control and also for soil and water conservation.





Research progress on effects of climate warming on soil organic carbon pools in frigid grasslands and its mechanisms.

LYU Wangwang, SUN Jianping, LYU Jingya, CHEN Lanying, LIU Shizhang, WU Jing, WANG Shiping

2024, 43(6):  1604-1611.  doi:10.13292/j.1000-4890.202406.005

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Global frozen regions include seasonally frozen and permafrost regions, which are mainly distributed in the high altitude and high latitude regions, and store substantial organic carbon in soils. The region is facing a higher rate of warming than global average level. Much attention has been focused on the effects of climate warming on soil organic carbon in the region and its feedback to climate warming. Here, we reviewed the effects of climate warming on the key processes of carbon cycling (e.g., plant production, decomposition of leaf and root litter, microbial community structure, etc.), as well as the formation and stability mechanisms of soil organic carbon in grasslands in the seasonally frozen and permafrost regions. We put forward scientific questions and analyzed the trends about experimental design and new technology application in the future to promote the research of key processes of carbon cycling and stability mechanism of soil organic carbon pool in the alpine grassland ecosystems under climate warming.





Contents and eco-stoichiometric characteristics of soil carbon, nitrogen, and phosphorus in alpine grasslands with different degradation degrees.

QIMANGULI·Palati, LIU Dan, MAO Jun, QIAO Fusheng, WANG Changting

2024, 43(6):  1612-1620.  doi:10.13292/j.1000-4890.202406.031

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To clarify the contents and ecological stoichiometric characteristics of soil carbon (C), nitrogen (N), and phosphorus (P) in alpine grasslands under different degradation degrees, we analyzed soil organic C (SOC), N, P, C∶N, C∶P and N∶P in undegraded (ND), lightly degraded (LD), moderately degraded (MD) and severely degraded (SD) alpine grasslands. The results showed that soil SOC, N, and P contents showed a decreasing trend with increasing degradation degree of grasslands. The average values of C∶N, C∶P, and N∶P were lower than the global level, all of which showed N-shaped changes with increasing degradation degree. Soil SOC, N, C∶P, N∶P, and N∶P were negatively correlated with soil pH and bulk density (P<0.05). Soil SOC, N, P, C∶P, and N∶P were positively correlated with soil water content (P<0.05). Soil P was not significantly correlated with soil bulk density (P>0.05). Soil C∶N was positively correlated with soil pH and bulk density (P<0.01), and negatively correlated with soil water content (P<0.01). Results of structural equation modeling indicated that grassland degradation directly affected soil physicochemical properties and thus soil SOC, N, and P content and their eco-stoichiometric ratio. In summary, grassland degradation changed soil microenvironment by reducing soil water content and increasing pH and bulk density, resulting in decreases in the contents of SOC, N, and P.





Spatial pattern and interspecific association of Beckmannia syzigachne and Kobresia tibetica in an alpine peatland.

WU Xianshi, ZHAO Chengzhang, MA Xinyu, WANG Suhong, ZHANG Peixian, HUANG Chenglu, LI Geyang

2024, 43(6):  1621-1628.  doi:10.13292/j.1000-4890.202406.014

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Studying the spatial distribution and environmental response of plants in alpine peatlands is of great significance for understanding the material cycling mechanism of alpine peatlands. Three plots with different water levels \[perennial waterlogged area (Ⅰ), seasonal waterlogged area (Ⅱ), and stage waterlogged area (Ⅲ)\] were set up in a peatland wetland in Langdutan on the eastern edge of the Tibetan Plateau. The spatial distribution pattern and interspecific associations between the populations of Beckmannia syzigachne and Kobresia tibetica in different water levels were analyzed using the small-scale point pattern analysis method. The results showed that: (1) with the decreases of surface water depth, the dominant species shifted from B. syzigachne to K. tibetica, soil organic carbon content gradually decreased, soil total nitrogen and total phosphorus contents showed an increasing trend; (2) with shifting from perennial waterlogged area to stage waterlogged area, the spatial pattern of B. syzigachne populations changed from aggregated to random distribution, and that of K. tibetica populations shifted from random to aggregated distribution; (3) the spatial correlations of B. syzigachne and K. tibetica were negatively correlated and non-correlated in perennial waterlogged area and stage waterlogged area, and negatively correlated in seasonal waterlogged areas. Spatial heterogeneity of inundation conditions, micro-geomorphology, and soil nutrient heterogeneity in alpine peatlands affect the spatial distribution pattern of populations and interspecific correlations, reflecting ecological adaptation strategies of plants in alpine peatlands.





Effects of plateau zokor disturbance on functional traits and functional diversity of plants in alpine meadow.

WANG Lei, BAO Daerhan, DONG Longming, YU Tao, YE Guohui, HUA Limin

2024, 43(6):  1629-1637.  doi:10.13292/j.1000-4890.202406.024

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To clarify the effects of plateau zokor (Eospalax baileyi) disturbance on functional traits and functional diversity of plants in alpine meadows, we utilized the spatial pattern index of zokor mounds to quantify disturbance intensity. A section of plateau zokor habitat on the eastern edge of the Qinghai-Tibet Plateau was segmented into four disturbance levels of light, moderate, severe, and extremely severe disturbance, with plots devoid of zokor mounds being served as a control. We measured plant species richness, functional traits of common plants, and soil physicochemical characteristics in all the plots. One-way ANOVA was applied to assess the variations in functional traits and functional diversity across the disturbance gradient. Additionally, full subset regression and redundancy analysis were employed to determine the influence of environmental factors on plant functional traits and functional diversity. The results showed that: (1) compared to the control, under the disturbance of plateau zokor, the community weighted mean of relative chlorophyll content and leaf carbon content significantly increased (P<0.05), while plant height, specific leaf area, and leaf nitrogen content in the disturbed areas significantly decreased (P<0.05); (2) Under the disturbance of plateau zokor, plant functional richness significantly increased (P<0.05), whereas functional divergence and the RaoQ index significantly decreased (P<0.05); (3) The differences in functional traits and functional diversity were marginal across the various levels of zokor disturbance intensity. (4) Results of redundancy analysis and full subset regression analysis showed that soil moisture and temperature were the main factors affecting the functional diversity of alpine meadow plants, with soil environmental factors explaining 41.6% and 27.3% of the variance in functional traits and functional diversity, respectively. Our results suggested that plateau zokor disturbance changed soil environmental factors (temperature and moisture), which in turn affected plant functional traits and functional diversity.





The response of plant leaf traits to simulated warming in the alpine region of Qinghai-Tibet Plateau.

WANG Huiqing, WANG Changshun, LYU Wangwang, JIANG Lili, LI Bowen, WANG Qi, SI Queduoji, WANG Shiping

2024, 43(6):  1638-1645.  doi:10.13292/j.1000-4890.202406.012

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Climate change may bring huge potential risks to alpine ecosystems of Qinghai-Tibet Plateau. Leaf traits can reflect the process and mechanisms of plant response to climate change. In this study, a free-air infrared heating method was used to simulate temperature increasing in Haibei alpine meadow in Qinghai. The effects of temperature increasing on eight leaf traits of eight species in an alpine meadow were examined. The results showed that five traits of some plants, including leaf size, vein length per area, vein mass per leaf mass, leaf mass per area, and leaf carbon isotope discrimination, changed significantly after eight years of warming, while the change of carbon-nitrogen content and carbon-nitrogen ratio was not significant. Leaf size was more sensitive to temperature changes than other traits. Increasing temperature had a significant long-term effect on leaf traits, but there were significant differences in the direction and degree of the responses of different traits. There were differences in the effects of warming on leaf traits of species with different distribution types and leaf vein types. Plants showed diverse responses to environmental changes, which were manifested in the differential response of the same traits of different plant species to climate. At the same time, they are also manifested in the coordinated responses of different traits of the same species to climate change.





The heritability and genetic correlation of flower traits and rewards in two Pedicularis species from eastern margin of Qinghai-Tibet Plateau.

LU Ningna, YANG Hainian, CHEN Xiaoshuang, LU Ying, CAI Wei, CHEN Yangyang, HE Haocheng, JIANG Qin, WANG Yinyin, LI Yajie, ZHANG Ying

2024, 43(6):  1646-1654.  doi:10.13292/j.1000-4890.202406.044

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Floral traits associated with reward quality information are often subject to pollinator preference and selection, the evolutionary potential of which would be reflected by genetic variation and genetic correlation. Pedicularis has a variety of corolla types, which are widely distributed in the Qinghai-Tibet Plateau. The evolution of Pedicularis has been shown to be closely related to pollinator selection. In this study, the heritability of flower attraction traits and rewards (pollen and nectar) and the size of genetic correlation between them were analyzed by quantitative genetic experiments using nectarless Pedicularis semitorta and nectar-containing P. kansuensis distributed along the eastern margin of the Qinghai-Tibet Plateau. The results showed that the heritability of flower height, flower size, and pollen quantity in P. semitorta was high, but the heritability of inflorescence number and flower number was low. In P. kansuensis, the heritability of flower height, helmet height, and sugar content was higher, while the heritability of flower size, inflorescence number, flower number, sugar concentration and nectar content was lower. There was no significant correlation between pollen quantity and flower traits in P. semitorta, suggesting that flower attraction traits do not reflect their reward amount. There was a significantly positive phenotypic correlation between sugar concentration and inflorescence number, flower number in P. kansuensis, but the genetic correlation was not significant. Nectar content had a significantly positive phenotypic correlation with flower size, flower height, and flower number, while nectar content had a significantly positive genetic correlation with flower size and height. The phenotypic and genetic correlation between sugar content and the measured floral traits were all significantly positive. Those results suggest that multiple floral traits can serve as honest signals of reward in P. kansuensis. The size of phenotypic and genetic correlations between floral traits and reward in P. kansuensis was significantly higher than that in P. semitorta. This may be related to the evolution of corolla morphology in Pedicularis. The stronger genetic correlation may limit the independent evolution of floral traits and reward in P. kansuensis, while the floral traits in P. semitorta have a higher potential for independent evolution. This study contributes to a better understanding of the formation and maintenance of plant diversity on the Qinghai-Tibet Plateau.





The effects of nitrogen forms on biomass allocation and photosynthetic characteristics of dominant species in alpine artificial grasslands.

2024, 43(6):  1655-1663.  doi:10.13292/j.1000-4890.202406.026

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We investigated the effects of different nitrogen forms on biomass allocation and photosynthetic characteristics of dominant species in alpine artificial grasslands, aiming to select nitrogen forms suitable for maintaining productivity. A randomized block design was used to examine biomass allocation pattern, leaf photosynthetic characteristics, and stoichiometric characteristics of dominant species in a 4-year-old mixed grassland of “Festuca sinensis Qinghai + Poa pratensis Qinghai” under four treatments: control (CK), amide nitrogen (U), ammonium nitrogen (A), and nitrate nitrogen (N). The results showed that nitrogen addition decreased the relative biomass of stems, increased that of leaves and ears, and increased the total aboveground biomass by increasing the biomass of stems and leaves within the range of 15-45 cm in plant height. The positive effect of different nitrogen forms on aboveground biomass showed a trend of U>N>A. Different nitrogen forms improved the photosynthetic performance of dominant species to varying degrees, with the effect on net photosynthetic rate and water use efficiency showing a trend of A>N>U. The three nitrogen forms did not affect leaf carbon content, but significantly increased nitrogen and phosphorus content and decreased carbonnitrogen ratio and carbon-phosphorus ratio, with the strength of the effect being U>N>A. Results of redundancy analysis showed that intercellular CO₂ concentration, stomatal conductance, and net photosynthetic rate were key photosynthetic variables affecting plant productivity, while leaf nitrogen content, phosphorus content, carbon-nitrogen ratio, carbon-phosphorus ratio, and nitrogen-phosphorus ratio were key factors affecting photosynthesis and productivity. Overall, amide nitrogen may be more beneficial for maintaining the productivity of alpine artificial grassland.





The spatiotemporal pattern and prediction model of NDVI in Qiangtang grassland based on random forest algorithm.

LI Cailin, SONG Yantao, ZHANG Jing, WU Yunna, SUN Lei

2024, 43(6):  1664-1673.  doi:10.13292/j.1000-4890.202406.037

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This study aimed to reveal the spatiotemporal variations and the influencing factors of vegetation in the Qiangtang grassland during 2001-2020, and to predict the change trends of vegetation under climate change scenarios. Based on the data of MODIS NDVI, temperature, precipitation, and wind speed, we explored the relationship between vegetation changes and meteorological factors. Furthermore, NDVI prediction models were establish with three machine learning algorithms of random forest, support vector machine, and random gradient descent regression. The optimal model with the best simulation accuracy was selected to simulate vegetation changes under multiple scenarios. We found that NDVI of the Qiangtang grassland showed a slight increasing trend with a growth rate of 0.0003 a^-1 from 2001 to 2020. The response of NDVI to temperature lagged by 3 months, precipitation lagged by 0-1 months. NDVI was negatively correlated with wind speed without lag. The random forest algorithm had the highest simulation accuracy (Adjusted R²=0.958). The scenario for improvement of vegetation coverage in the future included 1.0 ℃ increase in temperature, 25% increase in precipitation, and 25% decrease in wind speed. This study contributed to early warning of vegetation degradation, which would help vegetation conservation under climate change.





Distribution patterns and driving factors of grassland plant diversity along a precipitation gradient on the Qinghai-Tibet Plateau.

ZHANG Xiaoyan, FENG Ming, LIU Qianguang, YANG Guojiao, HU Zhongmin

2024, 43(6):  1674-1680.  doi:10.13292/j.1000-4890.202406.021

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The distribution patterns of plant diversity in the Qinghai-Tibet Plateau vary across spatial scales. However, the factors that drive these patterns are still unclear. We investigated plant community and soils in 33 grassland sites along a precipitation gradient from Qinghai-Tibet Plateau, and elucidated the patterns of plant species diversity from three aspects: α, β, and γ diversity. Linear regression and structural equation modeling (SEM) were used to explore the direct or indirect factors affecting the distribution patterns of plant diversity. We found that α diversity and γ diversity increased, while β diversity decreased with increasing precipitation. Increased precipitation enhanced α diversity directly by changing soil moisture and indirectly by increasing soil inorganic nitrogen content. Moreover, increased precipitation indirectly increased γ diversity by increasing soil N/P ratio and decreasing soil pH. In summary, changes of precipitation can alter soil physicochemical properties, and thus affect plant diversity at different spatial scales.





The impact of warming on soil microbial communities in an alpine meadow of the Qinghai-Tibet Plateau.

XIANG Xuemei, DE Kejia, LIN Weishan, FENG Tingxu, LI Fei, WEI Xijie

2024, 43(6):  1681-1690.  doi:10.13292/j.1000-4890.202406.045

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How climate warming impacts soil microbial diversity and composition has long been a focal point in the research area of biodiversity and ecosystem function. However, the extent to which different levels of warming affect soil microbial communities in alpine meadow ecosystems remains largely unknown. We conducted a field experiment with different warming levels (W1, W2 and W3 respectively represented a gradual increase in temperature) in an alpine meadow of Yushu, Qinghai Province, and investigated soil microbial communities using high-throughput sequencing. The results showed that: (1) Climate warming significantly increased soil bacterial α-diversity and β-diversity. Specifically, the Shannon index of soil bacteria was increased by 2.70%, 3.87%, and 8.73% under the W1, W2, and W3 treatments, respectively, while the Chao1 index of soil bacteria was increased significantly by 17.82% under the W3 treatment (P<0.05). (2) Acidobacteria and Proteobacteria were the dominant bacterial phyla, while Ascomycota and Basidiomycota were the dominant fungal phyla. As temperature increased, the abundance of bacterial taxa increased, whereas the fungal population decreased. (3) Functional prediction of bacteria and fungi based on the PICRUSt and FUNGuild databases revealed changes in the potential metabolic functions of bacteria and ecological functions of fungi after climate warming. Functional genes with relative abundances exceeding 2% under different warming levels included Biosynthesis of ansamycins, Biosynthesis of vancomycin group, and Valine, leucine, and isoleucine biosynthesis pathways. Warming increased relative abundances of uncategorized saprotrophic fungi and arbuscular mycorrhizal fungi. These findings demonstrate that climate warming would alter soil microbial community diversity, composition, and function in alpine meadows of the Qinghai-Tibet Plateau.





Responses of soil microbial structure and carbon cycling functions to degradation and artificial restoration of alpine meadows.

HUANG Peng, DING Mingjun, ZHANG Hua, XU Huan, ZOU Tian’e, ZHANG Yueju, ZENG Huan

2024, 43(6):  1691-1702.  doi:10.13292/j.1000-4890.202406.039

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We examined the impacts of degradation and artificial restoration of alpine grasslands on microbial communities and the related carbon cycling functions, with experiments being conducted on degraded alpine meadows and artificially restored grasslands in the Qinghai-Tibet Plateau. With metagenomic techniques, we analyzed the change of microbial structures and carbon cycling functions, and further explored the environmental factors driving the changes of carbon cycling functional genes. The results showed that degradation and artificial restoration of grasslands significantly altered soil and vegetation characteristics. The increase of soil microbial richness and diversity and the decrease of the relative abundance of dominant species indicated that microbial community tended to be homogeneous during degradation and artificial restoration of grasslands. The diversity of soil carbon cycling functional genes showed a trend of increasing, stabilizing, and increasing. The top 15 dominant species contributed more than 40% to carbon cycle functional genes, and such contribution decreased significantly under degradation and restoration of grasslands. The effect of individual soil or vegetation on microbial community structure was greater than that on microbial carbon cycling functional genes, while soil and vegetation interaction had stronger effect on the latter than the former. Specifically, carbon cycling functional gene diversity and abundance were significantly related to soil available nitrogen (ammonium nitrogen and nitrate nitrogen) and vegetation factors (coverage, biomass, and diversity). Our results contribute to a better understanding of microbial mechanisms of carbon cycling during meadow degradation and artificial restoration.





Responses of soil fungal community structure to spring grazing exclusion in alpine grassland.

ZHENG Wenxian, LI Shixiong, ZHAO Wen, LIU Jingjing, YIN Yali

2024, 43(6):  1703-1711.  doi:10.13292/j.1000-4890.202406.010

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To clarify the effects of spring grazing exclusion on vegetation characteristics, soil physical and chemical properties and soil fungal community characteristics of moderately degraded alpine meadow, two treatments of spring grazing exclusion and free grazing were set up in an alpine meadow of Qilian Mountains. Plant community were investigated and soil samples were collected during the season with peak plant growth after the ending of grazing exclusion. The results showed that grazing exclusion significantly increased plant community diversity index, evenness index and richness index by 80.00%, 50.94%, and 21.89% respectively (P<0.05). Grazing exclusion significantly increased plant biomass by 52.41% (P<0.05). After grazing exclusion, the ratio of aboveground to belowground biomass increased from 8.58% to 25.59%, indicating that the distribution pattern of plant biomass was changed. Grazing exclusion significantly increased the contents of soil organic carbon and total potassium by 10.64% and 1.10% (P<0.05), respectively, while decreased soil bulk density and pH by 17.83% and 4.60% (P<0.05), respectively. The relative abundance of Ascomycetes in soil increased while that of Mortierella decreased under grazing exclusion treatment. There was no significant difference in soil fungal community diversity index between the two treatments. The results of PCoA analysis showed that the interpretation rates of primary coordinates 1 (PCo1), primary coordinate 2 (PCo2), and principal coordinate 3 (PCo3) on the differences in fungal community structure were 17.58%, 12.07%, and 11.51%, respectively, with a cumulative interpretation rate of 41.16%. The modular analysis of fungal co-occurrence network showed that the complexity of soil fungal network was higher and soil fungal community was more stable under the treatment of grazing exclusion. The analysis of variance of vegetation and soil factors showed that soil water content and belowground biomass were the two main factors regulating the assembly of fungal community.





Altitudinal distribution of soil fungi at small scale in alpine grassland.

LIU Wenli, ZHANG Biao, ZHOU Shutong, LIU Wenjing, LIU Jiashuai, YAN Huifang, LI Zhiyong, CUI Xiaoyong, WANG Yanfen, XUE Kai

2024, 43(6):  1712-1719.  doi:10.13292/j.1000-4890.202406.023

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To understand the distribution pattern of soil fungal communities along an elevation gradient at small scale, the high-throughput sequencing technology was used to explore the diversity and composition of soil fungal communities in different soil layers (topsoil, 0-5 cm; subsoil, 5-20 cm) at three elevations (4902, 4944, 4989 m) in an alpine meadow of Noijin Kangsang Peak, Qinghai-Tibet Plateau, and the influencing factors were examined. Results showed that there was no significant difference in fungal diversity in the topsoil and the subsoil along the small scale elevation gradient, but community composition changed significantly (P<0.05). Moreover, soil fungal community composition in the topsoil was mainly affected by soil water content (SWC), carbon-nitrogen ratio (C/N), nitrogen-phosphorus ratio (N/P), carbon-phosphorus ratio (C/P), and plant diversity. With increasing elevation, SWC, N/P, C/P, and plant diversity increased, while C/N decreased, resulting in much higher relative abundance of Ascomycota_unclassified in low elevation (4902 m) than that in middle elevation (4944 m) and high elevation (4989 m). The difference in soil fungal community composition in the subsoil layer across the altitudinal gradient was mainly affected by belowground biomass and plant diversity. Both belowground biomass and plant diversity increased with elevation, resulting in higher relative abundance of Leotiomycetes at the low elevation than that in middle and high elevations. The Ascomycota_unclassified and Hymenochaetales were the indicator taxa in the topsoil at the class level and the order level, respectively. The Microbotryomycetes_unclassified and Helotiales were the indicator taxa in the subsoil at the order level. By exploring the distribution pattern and influencing factors of soil fungal community across a small-scale elevation gradient in alpine grasslands, our results provide great significance for understanding the driving mechanism of soil fungal community change.





Effects of land-use types on soil carbon and nitrogen stocks in the Napahai wetlands.

LI Wentao, HU Zunying, ZHANG Kun, LI Liping, QIU Yuping, GUO Xuelian

2024, 43(6):  1720-1727.  doi:10.13292/j.1000-4890.202406.036

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Land-use patterns in the wetlands of northwest Yunnan Plateau have undergone changes due to climate change and human activities. However, the impacts and mechanisms of these land-use changes on soil carbon and nitrogen stocks in the wetlands remain unclear. In this study, we analyzed the changes in soil organic carbon (TOC) and total nitrogen (TN) contents and stocks under different land-use types (wetlands, meadows, and croplands) of Napahai. Our aims were to elucidate the relationship between soil carbon and nitrogen stocks, plant biomass, and soil physicochemical properties under different land-use types, and to clarify the influencing mechanisms of land-use types on soil carbon and nitrogen stocks and main controlling factors. The results showed that soil moisture, TOC, TN content, aboveground biomass, and belowground biomass were significantly higher in wetlands than in croplands and meadows (P<0.05), while bulk density was significantly lower in wetlands (P<0.05). Soil carbon and nitrogen stocks in wetlands, croplands, and meadows decreased with increasing soil depth (0-100 cm). Carbon and nitrogen stocks were the highest in wetland soil, and the lowest in meadow soil. Soil organic carbon stocks showed a significant positive correlation with TOC content, carbon-nitrogen ratio, and aboveground biomass (P<0.01). Soil total nitrogen stocks were positively correlated with soil moisture, TOC and TN contents, and aboveground biomass (P<0.01), while negatively correlated with bulk density and carbon-nitrogen ratio (P<0.05). Land-use type, soil moisture, bulk density, and TOC content directly affected soil carbon stocks, while soil depth, land-use type, carbon-nitrogen ratio, and TN content directly affected soil nitrogen stocks. In summary, bulk density, soil moisture, carbon-nitrogen ratio, aboveground biomass, and belowground biomass were identified as the main factors affecting soil carbon and nitrogen stocks in Napahai wetlands. The carbon and nitrogen stocks in the soil of Napahai wetlands were highest in wetlands, followed by croplands and meadows, indicating that drainage of wetlands into meadows or conversion of wetlands into croplands will result in carbon and nitrogen losses in the soil of Napahai wetlands.





Soil microbial community structure in different ecosystem types of the Lhasa River Basin.

ZHANG Xiaoli, SUN Xiangyang, AN Baosheng, LI Suyan, LI Jiule, WANG Chuanfei, GAO Xiaoyuan

2024, 43(6):  1728-1737.  doi:10.13292/j.1000-4890.202406.047

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The Lhasa River Basin is known for its richness in agricultural resources, which are facing the most significant environmental pressure in Tibet. Changes in the structure and composition of soil microbial communities in the region can provide insights into soil ecology and environmental vulnerability under the influence of climate change and human activities. We analyzed soil microbial community structure and the environmental influencing factors in five ecosystems, including natural shrubland, sparse shrubland, artificial shrubland, artificial forest, and natural grassland, using high-throughput sequencing method. The results showed that: (1) Soil bacterial diversity and fungal diversity were highest in the artificial shrubland. (2) Soil bacteria in all the five ecosystems were dominated by Proteobacteria, Actinobacteriota, and Acidobacteriota, while fungi were dominated by Ascomycetes, Basidiomycota, Chytridiomycota, and Calcarisporiellomycota. (3) In the shallow layer, soil bacterial community clusters were similar in natural grassland and artificial forest. In the deep layer, soil bacterial community clusters were similar in natural shrubland, sparse shrubland, and artificial shrubland. Except for natural shrubland, fungal communities in all the ecosystems exhibited a trend of separation in both shallow and deep layers. (4) The structure of bacterial communities was significantly influenced by soil water content, electrical conductivity and available potassium, while the structure of fungal communities was mainly affected by soil water content, total nitrogen, available phosphorus and available potassium. These findings characterized the soil microbial community structure of different ecosystem types in the Lhasa River Basin.





Characteristics of vegetation index changes in Lhalu wetland over the past 20 years and their responses to climate change.

YANG Ao, YAN Liang, ZHANG Xiaodong, ZHANG Kerou, LI Yong, KANG Xiaoming

2024, 43(6):  1738-1746.  doi:10.13292/j.1000-4890.202406.011

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Plateau urban wetlands, as an important component of plateau urban ecosystems, play a critical role in maintaining economic development and ecological environment construction in plateau cities, yet the understanding of vegetation dynamics and their influencing factors remains elusive. We employed various vegetation indices to assess vegetation conditions in plateau urban wetlands and investigated their responses to climate change. We calculated the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), ratio vegetation index (RVI), and fractional vegetation cover (FVC) for the Lhalu Wetland National Nature Reserve in Qinghai-Tibet Plateau using Landsat multi-source image data during the vegetation growing season (May to September) between 2000 and 2020. Trend regression analysis was used to uncover the spatial-temporal variations of these indices and vegetation cover over the past two decades in Lhalu wetland, and their correlations with precipitation and temperature were explored. Our results showed that: (1) The FVC levels in the Lhalu wetland were relatively high, averaging at 0.57 from 2000 to 2020. Higher FVC values were observed in the central and southern regions. While the proportion of increasing FVC areas surpassed that of decreasing areas, the dominant trend (32.38% of areas) showed a non-significant increase. (2) NDVI and RVI displayed a strong correlation (R²=0.92, P<0.01), being more effective than EVI in monitoring FVC in Lhalu wetland. EVI exhibited high sensitivity to variations in vegetation growth, especially in areas characterized by dense vegetation coverage, while NDVI stood out as the most effective and adaptable index for accurately assessing and retrieving vegetation cover. (3) NDVI, EVI, and RVI indices displayed a negative correlation with temperature while showing a positive correlation with precipitation. Temperature exhibited a greater impact on vegetation indices. Our results highlight the relative stability and incremental improvement of FVC trends in Lhalu Wetland National Nature Reserve from 2000 to 2020. Spatially, vegetation indices showed higher values in the central and southern parts. Notably, NDVI was the most proficient index for vegetation assessment, surpassing RVI and EVI, with temperature showing a more pronounced influence on vegetation indices than precipitation. This research provides valuable scientific insights and empirical support for the conservation and restoration efforts in Lhalu Wetland National Nature Reserve.





Landscape pattern change of marsh in the Nanmoqie Wetland National Nature Reserve of Sichuan Province.

LYU Xuxiang, GOU Anying, CHEN Zhangmin, ZHANG Taxing, TAN Jinbo, RAN Jianghong

2024, 43(6):  1747-1755.  doi:10.13292/j.1000-4890.202406.034

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Alpine wetlands are typical wetland types on the Qinghai-Tibet Plateau, playing important roles in biodiversity maintenance and water conservation. Understanding the changes and driving factors for their landscape pattern is of great significance for the conservation and restoration of alpine wetlands in China. Based on GEE and Landsat satellite images, we used the random forest classification method to extract information on the distribution of marsh in the Sichuan Nanmoqie Wetland National Nature Reserve, for 12 periods from 1987 to 2022, and analyzed the spatial and temporal marsh landscape patterns and the driving factors. The results showed that: (1) the area of marsh first decreased and then increased, with an overall decrease of 10.29%; (2) the area conversion between marsh and meadow was highest, with a cumulative shift of 4349.44 hm² from marsh to meadow; (3) the centroid of marsh moved to the northeast first and then to the southwest, and the distribution range of marsh moved to the southwest as a whole; (4) the degree of fragmentation decreased and then increased, and the connectivity increased and then decreased instead. The shape of patches tended to be complex, and the landscape tended to develop from a compact state to a dispersed state; (5) the cumulative precipitation and average temperature during the growing season were the main factors affecting the pattern of marsh distribution. The results can provide a scientific basis for the conservation and restoration of alpine wetlands in the reserve and for the ecological security construction of alpine wetlands on the Qinghai-Tibet Plateau.





Climate characteristics of Yani National Wetland Park in Tibet.

LIU Changsheng, QU Xingle, REN Yihua, SUN Kaige, FANG Jiangping, ZHENG Du, XIANG Jun, LUO Daqing

2024, 43(6):  1756-1762.  doi:10.13292/j.1000-4890.202406.028

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We analyzed climate characteristics in the Yani wetland by carrying out climate monitoring by a standard automatic weather station in Yani National Wetland Park, Nyingchi City, Tibet Autonomous Region. During the period of 2019 to 2021, annual total radiation of the study area was 7474.25 MJ·m^-2; near ground annual net radiation was 3507.83 MJ·m^-2, with the daily average being greater than 0 MJ·m^-2. Photosynthetically active radiation was 11410.39 mol·m^-2. The total radiation, near ground annual net radiation, and photosynthetically active radiation in summer were 2260.91 MJ·m^-2, 1249.94 MJ·m^-2, and 3483.62 mol·m^-2, respectively. During the study period, annual total radiation was more than 6300 MJ·m^-2. The richness and stability of solar energy resources were at grade A. The average annual near-surface temperature in the wetland area was 10.09 ℃, and the highest temperature was in August with an average value of 17.39 ℃. The average temperature in January was 1.19 ℃. During the observational period, the nearsurface air temperature showed an overall rising trend, with a rate of 0.18 ℃·a^-1. The mean annual precipitation was 470.1 mm, which mainly concentrated in summer. The precipitation was 258.9 mm between June and September and only 15.03 mm in winter (January to February and December). The annual average wind speed was 5.8 m·s^-1, and the maximum daily average wind speed was 7.38 m·s^-1 from January to June. The minimum daily average wind speed was 4.3 m·s^-1 from July to September. South and southwest winds prevailed in the region, accounting for 85.4% of the days of a year. The variation of soil temperature showed a unimodal curve and was relatively stable. The average annual soil temperature of 0-40 cm in depth was 13.38 ℃, and soil heat budget was characterized by heat absorption from mid-February to mid-September, and heat loss from mid-September to mid-February of next year. The oxygen content of air showed a decreasing trend, being less in summer than in winter. The annual average oxygen content of air was 83.5%-87.8%, with a decreasing rate of 2.0%·a^-1. Collectively, the Yani wetland area has strong solar radiation and rich resources of light energy. The high level of heat, rainfall, and wetness indicate that the area is in a sub-humid zone. The annual temperature range increases and the warming and humidifying process appears clearly, which is consistent with the trend of climate change on the Qinghai-Tibet Plateau.





Response of leaf economic traits of natural Brasenia schreberi to water environment in high altitude area.

CHEN Hongyi, SUN Mei, LIU Zhenya, YANG Hangmei

2024, 43(6):  1763-1771.  doi:10.13292/j.1000-4890.202406.042

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Exploring the response strategies of natural Brasenia schreberi to water environment can provide a theoretical basis for the scientific protection of natural populations. The relationships between leaf economic traits of B. schreberi and water environmental factors were detected in natural B. schreberi community in 17 sites from Beihai wetland in Tengchong,  Western Yunnan Province. We measured functional traits and environmental factors of the sampling sites, and analyzed the response strategies of natural B. schreberi in high altitude area to water environment. The results showed that, compared to that under 100% coverage, B. schreberi with a coverage of 60%-70% had larger leaf area, and lower mass fractions of nitrogen, phosphorus, iron, and zinc (P<0.05).  Water dissolved oxygen content, volume fractions of nitrogen, phosphorus, and ammonium nitrogen, and water temperature were the main factors affecting leaf economic traits of B. schreberi. Photosynthetic rate was significantly positively correlated with water dissolved oxygen content and the volume fractions of ammonium nitrogen and nitrate nitrogen (P<0.05). Leaf thickness was significantly positively correlated with biochemical oxygen demand. Leaf area was significantly positively correlated with water dissolved oxygen content, volume fraction of ammonium nitrogen, and water temperature, and negatively correlated with water biochemical oxygen demand, chemical oxygen demand, and potassium permanganate index (P<0.05). Leaf mass fraction of nitrogen was significantly positively correlated with water volume fractions of nitrogen and ammonium nitrogen (P<0.05). Leaf mass fraction of phosphorus was also significantly positively correlated with water volume fraction of nitrogen, while it was significantly negatively correlated with water dissolved oxygen content and water temperature (P<0.05). Leaf nitrogen to phosphorus ratio was significantly positively correlated with dissolved oxygen content and volume fraction of ammonium nitrogen, but negatively correlated with chemical oxygen demand and potassium permanganate index (P<0.05). Potassium, magnesium, silicon, calcium, iron and zinc in B. schreberi leaves were mainly correlated to water dissolved oxygen content, water temperature, and the nutritional conditions of nitrogen and phosphorus. Our results will provide a theoretical basis for the scientific conservation of natural B. schreberi communities.





Water exchange of typical small watershed in Qinghai-Tibet Plateau based on hydrogen and oxygen isotopes tracing.

LI Jing, ZHANG Fawei, CAO Guangmin, GUO Xiaowei

2024, 43(6):  1772-1778.  doi:10.13292/j.1000-4890.202406.003

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Water cycling in Qinghai-Tibet Plateau is a hot topic. However, the research on water transport at the watershed scale is relatively weak. In this study, stable isotopes of hydrogen and oxygen (δ²H and δ¹⁸O) were used to determine the temporal and spatial variation of precipitation, shallow groundwater, middle-layer groundwater, marsh water, spring water, creek water, lake water and soil water in a typical watershed of Haibei National Field Scientific Observation and Research Station (Haibei Station) in Qinghai Province. The MixSIAR model was used to quantitatively analyze water source of each water body and their exchange. The results showed that there were significant differences in the characteristics of hydrogen and oxygen stable isotopes of different water sources. The variations of isotope values in lake water and precipitation were greater than that of other waters, and the isotope enrichment in lake water was higher than that of other water bodies. Shallow groundwater (3 m) was an important regulating reservoir for water conservation in small watershed, while spring water was the surface manifestation of shallow groundwater. Soil water was important in water conservation of small watershed, as well as the transition in vertical exchange of precipitation-shallow groundwater (3 m)-middle groundwater (20 m). Soil water and shallow groundwater replenished water to creeks and marshes through lateral runoff. This study provides a basis for the optimization of hydrological model and the utilization of water resources in small alpine watersheds.





Seasonal succession characteristics of phytoplankton functional groups in the middle and upper reaches of the Yarlung Zangbo River as an indicator of water environment.

CHAO Xin, LI Xiaodong, YANG Qing, LIU Huiqiu, YANG Shengxian, BA Sang

2024, 43(6):  1779-1788.  doi:10.13292/j.1000-4890.202406.029

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The functional group composition of phytoplankton can reveal community succession pattern and indicate the quality of water environment. The Yarlung Zangbo River is an important water system in China. The phytoplankton community structure and water environmental factors in the middle and upper reaches of the Yarlung Zangbo River were investigated in August (summer) and November (autumn) of 2019 and in May (spring) of 2020 to explore the seasonal variations of phytoplankton functional groups and their indicative roles on water environment. The results showed that: (1) Water in the middle and upper reaches of Yarlung Zangbo River was alkaline, with significant differences in water temperature, velocity and turbidity among the three seasons. (2) A total of 121 genera of phytoplankton were identified, belonging to 8 phyla, 11 classes, 24 orders, 44 families. The phytoplankton community structure was diatomic-green algae-cyanobacteria type as a whole. The phytoplankton community could be divided into 28 functional groups with 16 dominant functional groups. The composition of phytoplankton functional groups varied obviously with seasons. (3) The results of redundancy analysis and variance partitioning analysis showed that water temperature, pH, and dissolved oxygen content were the main environmental factors influencing the distribution of dominant functional groups. (4) The comprehensive evaluation based on the Shannon index (0.56-3.09, with an average of 2.20) and the ecological status index (1.92-4.91, with an average of 3.63) in three seasons showed that water quality of the middle and upper reaches of the Yarlung Zangbo River was at the level of “good”. This study revealed the characteristics of phytoplankton functional groups and their indicative roles on water environment, and provided a scientific basis for aquatic ecological research in the middle and upper reaches of the Yarlung Zangbo River.





Effects of landscape patterns on surface water quality and its characteristic scale in the Lashihai watershed of Yunnan Province.

ZHNAG Hongsen, JIAO Yuanmei, ZHANG Hua, ZHAO Lianxun, TAO Yan, XU Qiu’e, ZHANG Zhaonian

2024, 43(6):  1789-1798.  doi:10.13292/j.1000-4890.202406.001

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Identifying the impacts of landscape pattern on surface water quality and its characteristic scale is a hot and crux in the field of water environment research. In this study, the Lashihai watershed in northwest Yunnan Province was taken as the research area, and 50 water sample points were taken as the centers. With an interval of 50 m, landscape type composition and 10 landscape pattern indices of five buffer zones between 50 to 250 m were calculated, and their correlations with the total phosphorus and total nitrogen contents of water body were analyzed to identify the characteristic scale of the impact of landscape pattern on water quality. The results showed significant differentiation of watershedscale landscape pattern between mountainous areas and dam areas. The bufferscale landscape pattern index of water sample points changed significantly in the 100 m buffer zone. The average concentrations of TP and TN were 0.12 mg·L^-1 and 1.61 mg·L^-1 respectively, with a trend of continuous enrichment from upstream to downstream and an obvious spatial difference of pollution degree among the sampling points. Surface water TP concentration was higher in grassland adjacent to water body, and TN concentration was higher in the forest in the mountainous area. When the buffer zone of the water sample point was 100 m, the correlation between the landscape pattern and the surface water quality parameters was the highest. The TP concentration was significantly positively correlated with patch density, edge density, landscape shape index, landscape split index, and Shannon diversity index. Therefore, we should focus on the grassland in the dam area and the landscape pattern within 100 m around the Lashihai Lake to improve surface water quality.





Sources and natural attenuation of dissolved arsenic in Dogxung Zangbo River.

YAN Yani, ZHANG Junwen, ZHANG Dong, ZHAO Zhiqi

2024, 43(6):  1799-1806.  doi:10.13292/j.1000-4890.202406.030

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Some of rivers on the Qinghai-Tibet Plateau have high dissolved arsenic (As) levels, posing a potential threat to the health of local residents. To identify the sources and natural attenuation of dissolved As in the rivers, we analyzed the dissolved As concentrations in 11 river water samples, 3 hot spring samples, 2 lake water samples, and 1 rainwater sample collected from the Dogxung Zangbu River. Results showed that As concentration in the hot spring samples was up to more than 9000 μg·L^-1. The As concentrations in the two lake water samples were 14.1 and 93.8 μg·L^-1, respectively. The As concentrations of river samples ranged from 0.83 to 177 μg·L^-1 (mean 45.5 μg·L^-1), with 64% of the samples exceeding 10 μg·L^-1. The As concentration of rainwater sample was below 0.1 μg·L^-1. The As-rich hot springs were an important source of dissolved As in river water, while other sources contributed less. From upstream to downstream, dilution, adsorption, and co-precipitation of As by river suspended matter or sediments are important processes for the natural attenuation of dissolved As in river water. These As-enriched river suspended matters or sediments are transported downstream and deposition, which may lead to high As levels in sediments and groundwater in downstream regions, thus affecting the drinking water safety of local residents.





Soil heavy metal risk evaluation and source analysis of Zhaxigang wetland in Tibet based on PCA-APCS-MLR Model.

YANG Jueyuan, XIONG Jian, LI Wei, HUANG Ruiqing, YANG Bo, XIE Pengcheng

2024, 43(6):  1807-1816.  doi:10.13292/j.1000-4890.202406.038

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Zhaxigang wetland is a typical plateau meadow swamp and an important ecological function reserve in Lhasa. Wetlands in Tibet are extremely fragile due to climate and topography, which should be given full consideration. To accurately assess the pollution status and sources of heavy metals in the soil of Zhaxigang wetland, we analyzed the contents of seven heavy metal elements (Cr, Ni, Zn, Pb, Cd, As and Hg) in 18 surface soil samples of Zhaxigang wetland. The pollution risks of heavy metals were evaluated by using the method of geo-accumulation index (I_geo) and pollution loading index (PLI). Based on PCA, the APCS-MLR model was used to analyze the pollution sources of heavy metals. The results showed that: (1) The contents of Cr and Ni in the surface soil of Zhaxigang wetland were lower than the background value of Tibetan soil. The contents of the other five elements were accumulated in different degrees. Except for Cd and As, the measured values of the other five elements were lower than the risk screening value in “Soil Environmental Quality Risk Control Standard for Soil Contamination of Agricultural Land of  (GB 15618-2018)”. (2) Except for Cd and Hg, the I_geo values of other elements were less than 0, indicating a clean level. The overall PLI in the study area was 1.44, indicating light ecological hazard. Both evaluations showed that Cd and Hg were the main pollution elements in this area. More attention should be paid on those two elements, and routine monitoring should be strengthened. (3) The sources of heavy metals were mainly mixed industrial-transportation sources, natural sources, and mixed agricultural-coal combustion sources. Ni, Zn, Pb, Cd, and As were mainly from mixed industrial-transportation sources, Cr was mainly from natural sources, and the sources of Hg were mainly affected by human activities such as agriculture and coal combustion.





Effects of warming on soil microbial diversity and carbon sequestration in drylands.

ZHANG Shaoyang, FAN Dandan, KONG Weidong

2024, 43(6):  1817-1823.  doi:10.13292/j.1000-4890.202406.017

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Drylands, which cover about 41% of the Earth’s land area, are typical ecologically fragile areas and sensitive to climate change. Soil microbial community plays a crucial role in maintaining ecosystem structure and function in drylands, such as carbon and nitrogen cycling. However, the findings regarding the impacts of climate warming on soil microbial communities in drylands exhibit considerable variation across different studies. Here, we reviewed the responses of soil microbial (bacteria and fungi) diversity and community structure to climate warming, elucidated the underlying reasons for the observed disparities, and conducted a thorough analysis of how warming affects soil microbial functions in regulating soil carbon cycling. Finally, we proposed future development directions: (1) monitoring dynamics of soil microbial communities in various ecosystems at large spatial scale involving the interaction of multiple global change factors in drylands; (2) expanding the studies of microbial community at different warming extents and ecosystems for long period; and (3) thoroughly investigating the roles of soil microorganisms in carbon sequestration and mineralization in drylands, by employing multi-omics analytical methods. These efforts will provide a scientific foundation for the sustainable management of dryland ecosystems.





Spatial differentiation of cropland soil organic carbon and influencing factors in the Yarlung Zangbo River, Nyangqu River and Lhasa River region of Tibet.

TAN Gefei, WANG Zhaofeng, ZHANG Yili, GONG Dianqing, HU Xiaoyang

2024, 43(6):  1824-1832.  doi:10.13292/j.10004890.202406.040

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Soil organic carbon (SOC) in croplands plays an important role in stabilizing the ecological environment and food security. Exploring the spatial variations and influencing factors of SOC is of great significance for promoting the sustainability of regional agriculture. We analyzed the spatial differentiation characteristics and influencing factors of cropland SOC using redundancy analysis (RDA) and structural equation model (SEM), with 150 sampling points from cropland topsoil across the Yarlung Zangbo River, the Nyangqu River, and the Lhasa River region (the YNL river region) in Tibet. The results showed that cropland SOC in the YNL river region was low in the west and high in the east, and low in the mainstream valley of the Yarlung Zangbo River and high in the source areas of the north and south tributaries. Overall, the average SOC content in the YNL river region was relatively low. Soil silt content was the dominant factor in the regional spatial variations of SOC, explaining 14.0% of total variation. Mean annual evaporation (MAE) could better explain the spatial variations of SOC than mean annual temperature (MAT) and mean annual precipitation (MAP). The SOC content in this region mainly showed vertical and meridional zonality. Altitude affected SOC levels indirectly by affecting temperature and evaporation, while longitude affected it indirectly by affecting precipitation and soil pH. The spatial variations of SOC content were indirectly affected by climate, vegetation, and soil properties. This study provides a scientific basis for the prediction of spatial variations of SOC and regional agricultural development.





Responses of soil water carrying capacity for vegetation in different sandy land types in Zoigê to climate change based on the Biome-BGC model.

ZHANG Chenfeng, HE Li, DONG Tingfa, DENG Dongzhou, LIU Junyan

2024, 43(6):  1833-1840.  doi:10.13292/j.1000-4890.202406.007

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Zoigê is a sensitive region to global climate change and a key ecological barrier for the upper reaches of the Yellow River and Yangtze River in China. However, soil water carrying capacity for vegetation (SWCV) in this area under global climate change is still unclear. We used the Biome-BGC model to simulate water use efficiency (WUE) of typical Hippophae rhamnoides dominated vegetation on four types of sandy land (fixed sand land, semi-fixed sand land, shifting sand land, and exposure sand land) under various climate change scenarios from 2007 to 2021. The SWCV of H. rhamnoides on different types of sandy land was estimated based on the model. The results showed that under different climate scenarios, annual average WUE of H. rhamnoides ranked as exposure sand land > fixed sand land > semi-fixed sand land > shifting sand land. Compared to current climate scenario, WUE was generally lower under future climate change scenarios. Under the scenario with increased temperature and precipitation, WUE was the lowest among all scenarios. SWCV was ranked as fixed sand land > semi-fixed sand land > shifting sand land > exposure sand land under different climate scenarios. Compared to current climate scenario, the SWCV decreased on all types of sandy land under future climate change scenarios. Precipitation and temperature had a coupled effect on SWCV, with precipitation having a greater impact than temperature. By revealing the responses of SWCV on different sandy land types in the Zoigê area to climate change, this study provides guidance for ecological management and restoration of alpine sandy land in the region.





Spatiotemporal variation of water use efficiency in response to self-calibrating Palmer drought severity index in Yulong Snow Mountain and surrounding areas, China.

LI Lili, YANG Yongming, WANG Dawei, MA Xinggang, DU Jia, LU Ruping, LI Yongheng, WANG Shijin

2024, 43(6):  1841-1850.  doi:10.13292/j.1000-4890.202406.002

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Yulong Snow Mountain and its surrounding area  a typical monsoon marine-like glacier region, which is the most suitable area for studying glacier change, geo-air energy exchange, vegetation community succession, and ecosystem carbon-water coupling. Water use efficiency (WUE) is an important parameter linking ecosystem water-carbon cycle and its response to climate factors. In this study, MODIS satellite remote sensing products \[gross primary productivity (GPP) and evapotranspiration (ET)\] and self-calibrating Palmer drought severity index (scPDSI) were used to analyze the spatial variation of WUE in Yulong Snow Mountain and its surrounding area from 2000 to 2020. The relationships between GPP, ET, WUE, and scPDSI were investigated, and the adaptation strategies of vegetations in different landforms to water use and stress were discussed. The results showed that during 2000-2020, the average WUE, GPP, and ET was 2.44 g C·m^-2·mm^-1, 1365.0 g C·m^-2, and 559.6 mm in the study area, respectively. The highest average WUE (2.88 g C·m^-2·mm^-1) was mainly distributed in intermediate relief and sub-high altitude mountains, and the lowest average WUE (1.23 g C·m^-2·mm^-1) was distributed in the high relief and extremely high altitude mountains. Due to the undulating terrain of Yulong Snow Mountain and the significant vertical zonal characteristics of vegetation, WUE increased with altitude below 3500 m, while decreased with altitude above 3500 m. During 2000-2020, the monthly WUE presented a trend of increase-decrease-increase. The change rate of WUE was significantly different due to different geomorphological types. The WUE in large undulating mountains of Yulongxue Mountain and its surrounding area showed an increasing trend, while that of the middle elevation plain showed a decreasing trend. In the whole study area, there were seasonal variations for the response of WUE to drought stress. The monthly correlation between WUE and scPDSI showed a trend of negative correlation-positive correlation-negative correlation-positive correlation, respectively. In the Yulong Snow Mountain area, WUE and scPDSI showed a significant positive correlation in July, but a negative correlation in May. There was a negative correlation between WUE and scPDSI from December to June of the following year, and a positive correlation between July and August in the area around Yulong Snow Mountain.





The impact of climate change on vegetation characteristics in Hoh Xil Nature Reserve.

LI Xiuping, HAO Shilong, YAO Ruichen, ZHANG Yan

2024, 43(6):  1851-1858.  doi:10.13292/j.1000-4890.202406.004

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Based on the GIMMS NDVI and MODIS NDVI datasets, we constructed a long-term GIMMS-MODIS NDVI dataset of 1982-2020 in Hoh Xil with a simple linear regression model. We analyzed the temporal and spatial variations of NDVI by adopting trend analysis, significance test, and correlation analysis, and analyzed the responses of NDVI to temperature and precipitation based on pixel scale. The results showed that the average annual temperature and precipitation showed a significant rising trend in Hoh Xil from 1982 to 2020, with a rising rate of 0.06 ℃·a^-1 and 5.59 mm·a^-1, respectively. The NDVI increased gradually from northwest to southeast of Hoh Xil during 1982-2020. The NDVI value was the largest and varied most obviously in summer, while it was the smallest and tended to be stable in winter. The annual average NDVI showed a non-significant positive correlation with the average annual temperature. At the pixel scale, the correlations between NDVI and temperature were predominantly positively, surpassing that between NDVI and precipitation. The correlation was the strongest in autumn. The impact of temperature on NDVI outweighed that of precipitation.





Comparative analysis of gross primary productivity in the Qinghai-Tibet Plateau based on longtime series of remote sensing products.

LIAO Weijie, JIAO Yue, LI Shixi, HU Zhongmin, BAI Lei

2024, 43(6):  1859-1869.  doi:10.13292/j.1000-4890.202406.006

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The Qinghai-Tibet Plateau is a hotspot in the research of terrestrial carbon cycling. In the context of global climate change, gross primary production (GPP) plays a crucial role in regional carbon cycle. Model simulation combined with remote sensing data aids in understanding the changes of ecosystem productivity at the regional scale across the Qinghai-Tibet Plateau and predicts its future trends. With six common remote sensing GPP products (GLASS, MODIS MOD17A2, FLUXCOM, VODCA2, improved EC-LUE data, and VPM data) being validated by eddy covariance flux observation data from three sites (Haibei shrub, Haibei wetland, and Damxung), we used them to analyze the spatial distribution pattern and temporal change trend of GPP in the Qinghai-Tibet Plateau ecosystems from 2001 to 2015. We found significant differences in annual mean GPP, annual total GPP spatial distribution pattern, and the trends across different remote sensing GPP datasets. The trends calculated based on the six products are -0.77 g C·m^-2·a^-1 (GLASS), 3.63 g C·m^-2·a^-1 (MOD17A2), -1.21 g C·m^-2·a^-1 (FLUXCOM), 1.53 g C·m^-2·a^-1 (VODCA2), 4.73 g C·m^-2·a^-1 (VPM), and -0.81 g C·m^-2·a^-1 (improved EC-LUE). The overall spatial distribution of multi-year mean GPP generally displays a pattern of higher values in the southeast and lower values in the northwest, with significant regional variations. The GLASS product shows the highest multi-year average annual GPP (827.78 Tg C·a^-1), while the MOD17A2 product shows the lowest (484.04 Tg C·a^-1). The other products (VODCA2, improved EC-LUE, VPM, and FLUXCOM) report 827.20 Tg C·a^-1, 714.55 Tg C·a^-1, 634.00 Tg C·a^-1, and 587.86 Tg C·a^-1, respectively. Over the 15 years from 2001 to 2015, the regions with the most significant changes in GPP are consistent across the plateau, with the most intense changes in the southeast and the most stable in the west. Site data validation indicates that MOD17A2 performs relatively better on an 8-day scale, whereas the FLUXCOM dataset shows superior results on a monthly scale. Combined with its performance at the regional scale, the MOD17A2 dataset is more suitable for the Qinghai-Tibet Plateau region.





Ecological protection and restoration zoning of national territorial space based on ecological resilience: A case study of the Taohe River Basin.

WANG Shiying, XIE Baopeng, YANG Jie, PEI Tingting, CHEN Ying, LIN Mingfang

2024, 43(6):  1870-1880.  doi:10.13292/j.1000-4890.202406.033

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Ecological restoration of territorial space is an important measure to implement the strategy of ecological civilization construction. Scientific delineation of ecological restoration zoning is the basic premise for the orderly promotion of ecological restoration of territorial space. Taking the Taohe River Basin as a case, we developed an analytical framework for assessing ecological resilience, focusing on ecosystem resistance capacity, ecosystem recovery capability, and ecosystem adaptability. Using this framework, we evaluated the ecological resilience of Taohe River Basin, outlined the zoning for ecological restoration of the territorial space, and proposed corresponding measures for ecological restoration. The results showed that there were substantial spatial differentiations of ecosystem resistance and adaptability indices in the Taohe River Basin, and a lack of natural transition between low-value areas and high-value areas. Spatial differences in ecosystem recovery index were evident, with higher ratings of ecosystem recovery capability from north-east to south-west. Ecological resilience showed circular distribution characteristics in space. Based on the results of resilience evaluation, the ecological restoration zoning of territorial space in Taohe River Basin was divided into five types, among which the vulnerable areas with low ecological resilience were distributed in the northern part of the basin, accounting for 7.49% of the basin area. The improvement area of ecological adaptability was mainly distributed in the Gannan Plateau, accounting for 34.04% of the basin area. The area of enhanced ecosystem recovery capability depended predominantly in the northern-central sector of the basin, encompassing 6.39% of the total basin area. Conversely, there was no designated area for boosting ecological resistance, constituting 16.57% of the total basin area. The protected areas with high ecological resilience were mainly distributed in the middle of the basin, accounting for 35.52% of the basin area. According to the zoning results, nature-based ecological restoration measures are proposed to improve forest and grassland coverage and increase landscape types, in order to provide reference for ecological protection and restoration.





Spatial-temporal variations of ecosystem service value in Sanjiangyuan National Park.

XU Haiying, YANG Chao, LI Qingquan

2024, 43(6):  1881-1890.  doi:10.13292/j.1000-4890.202406.008

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Sanjiangyuan National Park is one of the most sensitive and fragile ecosystems in China. Assessing and simulating ecosystem service value (ESV) can fill the knowledge gap for ecological protection and restoration. We constructed an ESV assessment model based on economically modified equivalent factor method and land use data to explore the spatial-temporal variations of ESV in Sanjiangyuan National Park from 2005 to 2020. The Patch-generating Land Use Simulation (PLUS) model was used to predict the characteristics of ESV under four scenarios (i.e., natural evolution, water protection, forest and grassland vegetation protection, and ecological protection) in 2035. The ESV of Sanjiangyuan National Park showed an increasing trend from 3.77×10¹¹ yuan in 2005 to 3.93×10¹¹ yuan in 2020. The ESV was affected by water, grassland, snow/ice and barren land. The change of water area had a significant impact on the change of ESV (with an average contribution rate of 67.8%). Under the four scenarios simulated by PLUS model, the ESV values in 2035 were higher than that of 2020. The ecological protection scenario had the highest ESV, reaching 4.21×10¹¹ yuan, an increase of 7.2% compared to 2020. Our findings suggest that the comprehensive ecological protection of forests, grasslands, and water areas should be emphasized in the resource protection planning of Sanjiangyuan National Park to promote the improvement of ESV.





Characteristics of soil seed bank in typical coal mine restoration areas at different altitudes in the Qilian Mountains Nature Reserve.

YANG Jingyi, ZHAO Wenzhi, LUO Weicheng, LIU Jiliang

2024, 43(6):  1891-1900.  doi:10.13292/j.1000-4890.202406.032

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Soil seed bank is a potential reserve of plant diversity, which could influence the revegetation and ecological restoration of mining areas. Through field investigations and experiments, we examined the characteristics of soil seed banks in typical coal mine restoration areas and control areas (undamaged) in the Qilian Mountains Nature Reserve at different altitudes and explored the relationship between species composition of soil seed banks and soil factors. The results showed that the density of soil seed banks in the restoration and control areas increased with altitude. The density of soil seed banks in the restoration areas was significantly lower than that in the control areas at the same altitude (P<0.05). Margalef richness index, Shannon diversity index, and Simpson diversity index of soil seed bank in the restoration areas were significantly lower than those in the control areas at altitudes of 2510 and 2630 m (P<0.05). The Sorenson similarity of species composition between aboveground vegetation and soil seed banks in the restoration areas decreased with altitudes. Results of the redundancy analysis showed that soil factors such as soil organic matter, total nitrogen, soil bulk density and soil water content were significantly correlated with species composition of the soil seed bank (P<0.001). Collectively, there is a significant difference in soil seed bank characteristics between the coal mine restoration areas and the control areas in the Qilian Mountains Nature Reserve, especially in the sites of 2510 and 2630 m altitudes. Other measures (such as artificial seed addition and improvement of soil properties) are needed to consolidate the restoration effects.





Matching supply and demand of ecosystem services in Qilian Mountain National Park.

CHEN Hong, DENG Xiaohong, LI Zongxing, XUE Jian

2024, 43(6):  1901-1909.  doi:10.13292/j.1000-4890.202406.046

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Analyzing the supply and demand of ecosystem services is crucial for integrated ecosystem management and achieving regional sustainable development. Using the InVEST model, we quantified the supply and demand of seven ecosystem services of Qilian Mountain National Park, including food provision, water conservation, soil conservation, carbon sequestration, climate regulation, habitat quality, and recreation and leisure. We further analyzed the supply and demand characteristics and spatial matching patterns by combining with the supply-demand ratio and the local Moran’s index. The results showed that the overall supply-demand ratio for Qilian Mountain National Park was 0.0608. Except for carbon sequestration and recreation and leisure services, the supply of the other five services exceeds demand. However, there were significant spatial variations across regions and services. The spatial matching between supply and demand could be categorized into four types, including high-high match, low-low match, low-high mismatch, and high-low mismatch. Tianzhu County and Sunan County were classified into the low supply-high demand category, while Shandan County, Minle County, and Liangzhou District were classified as high supply-low demand areas. High-low spatial mismatch areas within the Qilian Mountain National Park should be protected and the management level should be improved, while the low-high spatial mismatch areas should be comprehensively improved to enhance land-use efficiency.





Camera-trapping survey on the snow leopards and their sympatric mammals and birds in the Qilian County, Qilian Mountain National Park.

WANG Dong, WANG Zihan, LI Quanbang, GAO Yayue, SU Xu, LIAN Xinming

2024, 43(6):  1910-1919.  doi:10.13292/j.1000-4890.202406.035

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Species inventories are the fundamental basis for biodiversity research and conservation. Long-term monitoring of wildlife diversity and photographic evidence of the species are essential for updating the inventory. The Qilian County sector of Qilian Mountain National Park exhibits distinct variances in natural ecosystems from east to west, providing diverse habitats for wildlife communities. In the present study, a total of 187 infrared cameras were strategically placed at sites with spoors of snow leopard (Panthera uncia) or other sympatric wildlife within 5 km × 5 km grids. From September 2017 to December 2021, 44946 valid camera-days were accumulated, and 14330 independent and valid photographs were captured, including 466 snow leopard photographs. Utilizing this comprehensive dataset, a total of 78 distinct species were identified, including 27 mammalian species from five orders and 12 families, and 51 avian species from seven orders and 18 families. Nine species are designated as first-class protected species under China’s conservation legislation, while 20 are categorized as second-class protected species. Furthermore, 40 of the identified species were listed in the catalog of species with significant ecological, scientific, and societal value. In accordance with the International Union for Conservation of Nature (IUCN) Red List assessments, one species is classified as endangered (EN), three as vulnerable (VU), and five as near threatened (NT). Similarly, China’s Vertebrate Red List identified three critically endangered (CR) species, five endangered species, several vulnerable, and 17 near threatened species. Relative abundance index (RAI) analysis demonstrated that the most prevalent mammalian species in this region were blue sheep (Pseudois nayaur, RAI=128.18), Himalayan marmot (Marmota himalayana, RAI=50.17), red fox (Vulpes vulpes, RAI=11.30), woolly hare (Lepus oiostolus, RAI=10.72), and snow leopard (RAI=10.37). For avian fauna, the top-ranking species based on RAIs were black redstart (Phoenicurus ochruros, RAI=8.30), Tibetan snowfinch (Tetraogallus tibetanus, RAI=5.18), red-billed chough (Pyrrhocorax pyrrhocorax, RAI=3.87), rufous-necked snowfinch (Pyrgilauda ruficollis, RAI=4.32), and common magpie (Pica pica, RAI=3.65). We recorded three newly distributed species in the Qilian Mountains, including stoliczka’s mountain vole (Alticola stoliczkanus), Tibetan snowfinch (Montifringilla henrici) and Pallas’s leaf warbler (phylloscopus proregulus). Additionally, infrared cameras frequently captured evidence of livestock and human activities in the area (RAI=56.09).  These findings provide data support for both regional biodiversity inventories and effective wildlife protection strategies within the Qilian Mountain National Park.





Impacts of anthropogenic activities on the habitat of musk deer in the Xinglongshan National Nature Reserve on the eastern edge of the Qinghai-Tibet Plateau.

LI Haiping, ZAN Liao, ZHOU Xin, ZHANG Ronghong, WANG Gong, QI Jun, MENG Xiuxiang

2024, 43(6):  1920-1927.  doi:10.13292/j.1000-4890.202406.041

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Human activities have significant effects on the habitat suitability and utilization of wildlife. The establishment of nature reserves can, to a certain extent, reduce or even avoid excessive human interference with wildlife. The Xinglongshan National Nature Reserve in Gansu Province is located on the eastern edge of the Qinghai-Tibet Plateau. Alpine musk deer (Moschus chrysogaster) protected in this reserve, is critically endangered and has been listed as a national key protected species. To investigate the impacts of anthropogenic activities on the habitat of musk deer within and around the Xinglongshan Nature Reserve, we analyzed the changes in musk deer habitat caused by human activities with high-resolution satellite data in 2017 and 2022 and the methods such as the standard deviation ellipse calculation, landscape pattern indices and spatial overlay. The results showed that: (1) Human activities within and around the reserve exhibited a clear directionality, which was closely aligned with the concentrated distribution of roads and residential areas in the northwest to southeast direction, with angles ranging from 36° to 54° south by east. (2) The number of patches of farmland and construction land increased, coupled with a decrease in the average patch size, increasing habitat fragmentation. (3) The suitable habitat areas within the reserve shrank obviously. The spatial distribution of suitable habitat (294.27 km²) of musk deer in the reserve and its surrounding area was different from that of the existing protected area. Some suitable habitat (103.05 km²) was outside the reserve, which should be included into the reserve.





The diversity of locusts and katydids and its relationship with environmental factors at different altitudes in the Gaoligong Mountains.

LI Yonghui, ZHU Qidi, HE Shan, YANG Hui, PIAN Li, TAO Hong, LIU Qing, TANG Guowen

2024, 43(6):  1928-1936.  doi:10.13292/j.1000-4890.202406.013

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To clarify the diversity of locusts and katydids and its relationship with environmental factors at different altitudes in the Gaoligong Mountains, we investigated species composition of locusts and katydids at altitudes 1200-2400 m in September-October of 2020 and 2021 by using transect method. The whole survey area was divided into three altitude sections: Altitude section I (1200-1600 m), altitude section II (1600-2000 m), and altitude section III (2000-2400 m). A total of 741 insects were collected, representing 52 species, 35 genera, and 7 families. There were 426 specimens of 30 species, 24 genera, and 7 families in altitude section Ⅰ, 201 specimens of 15 species, 12 genera and 4 families in the altitude section Ⅱ, and 114 specimens of 13 species, 12 genera and 2 families in altitude section Ⅲ. Tettigoniidae, Catantopidae, and Rhaphidophoridae were dominant families, and Phlugiolopsis montana was the most dominant species in this region. Species richness, Shannon index, Margalef richness index, and Simpson dominance index were highest in the altitude section Ⅰ. The similarity coefficients between the three altitudes were between 0 and 0.1026, with highest similarity between the altitude section Ⅱ and Ⅲ. Results of correlation analysis showed that environmental factors significantly affected community diversity of locusts and katydids, but there were differences among different metrics. Temperature was negatively correlated with species richness but positively correlated with Pielou evenness index. Precipitation was negatively correlated with Shannon index, individual number, and species richness. Temperature and precipitation were the dominant factors in shaping the spatial pattern of locusts and katydids community diversity, and habitat heterogeneity increased species richness of these two groups in the Gaoligong Mountains.