Table of Content

10 April 2021, Volume 40 Issue 4

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Effects of nitrogen and phosphorus additions on belowground biomass of temperate typical steppe in Inner Mongolia.

GUO Xuan, HU Zhong-min, LI Sheng-gong, GUO Qun

2021, 40(4):  929-939.  doi:10.13292/j.1000-4890.202104.003

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Lines of evidence show a saturated rate of nitrogen (N) addition for enhancing aboveground biomass (AGB), with phosphorus (P) limitation as one of the most important casual factors. However, whether belowground biomass (BGB) can mirror the responses of AGB remains unknown. Moreover, it is unclear that whether simultaneous additions of N and P could alleviate the limitation caused by single nutrient addition. To clarify the response patterns of BGB to N and P additions, we conducted a fouryear manipulative experiment (N addition: 10 and 40 g N·m^-2·a^-1; P addition: 5 and 10 g P·m^-2·a^-1) in a temperate typical steppe of Inner Mongolia, China. The results showed that total BGB and that of surface layer (0-5 cm) tended to increase with increasing rates of N addition. However, only the high rate of N addition (40 g N·m^-2·a^-1) led to significant promotion of BGB in some years. P addition did not affect BGB, irrespective of the addition rate. Moreover, P addition did not affect the response of BGB to nitrogen addition. Nitrogen addition distinctly reduced or increased the extent to which BGB responded to P addition in a few cases. Nitrogen addition had relatively insignificant influence on BGB changes induced by P addition. Our results provide a better understanding of the responses of grassland belowground biomass to the enhanced N and P deposition, with important implications for grassland management.

Biomass allocation and growth analysis of the ramets of Phragmites communis in different growth stages in Zhalong wetland.

JIAO De-zhi, LIU Run-ze, PAN Lin, WANG Su-ling, YANG Yun-fei

2021, 40(4):  940-949.  doi:10.13292/j.1000-4890.202104.001

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Biomass and its allocation, as ecological adaptation strategy of plants, affect plant growth and reproduction. By using large sample method, we analyzed the biomass allocation of ramets of Phragmites australis in two growth stages at different habitats of Zhalong wetland. The results showed that the ramet height, leaf weight, leaf sheath weight, stem weight and ramet weight of P. australis at different habitats were different in the two growth stages, and that the growth of the ramets and modules of P. australis showed great plasticity. The ranges of average proportion of biomass allocation of ramet modules in P. australis were 31.72%-35.29% and between 12.77%-67.51% respectively. There was no significant difference among modules in June (P>0.05), but significant difference among modules in August (P<0.05), with stem being the largest, leaf the second, and leaf sheath the smallest. There was an allometric growth relationship by power function between remat height and ramet weight and the weight of different modules, and also between the weight of different modules and ramet weight. With the increases of ramet weight, the contribution rates of leaves, leaf sheaths and stems were 29.8%-46.6%, 14.9%-31.5% and 20.6%-55.2%, respectively. Our results suggested that the strategies of biomass allocation of ramet in different growth periods and habitats were different, and that there was a stable cooperative growth relationship between the photosynthetic module and the supporting module of the ramet. Moreover， the relative growth between ramet and module was controlled by both genetic and environmental factors.

Plant species diversity and its relationship with environmental factors in Laoshifuhai wetland of Ningwu, Shanxi.

LI Jing, WANG Heng, HU Jie, ZHAI Bi-jiao, REN Xiang-ning, WANG Chun-ling

2021, 40(4):  950-958.  doi:10.13292/j.1000-4890.202104.020

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Laoshifuhai wetland is one of the alpine lakes in Shanxi Province. Understanding plant species composition, diversity, and their relationships with environmental factors is the prerequisite for indepth study of wetland communities. Based on the data of 28 plots (with a size of 1 m×1 m) of Laoshifuhai wetland, we analyzed species composition of plant communities in this area. We used cluster analysis, ordination analysis and diversity indices to explore the classification, characteristics and species diversity of wetland associations, as well as the relationship between plant community and environmental factors. The plant community in Laoshifuhai wetland could be classified into Polygonum tenellum+Heleocharis dulcis association, Hippuris vulgaris+Nymphoides peltatum association, Hippuris vulgaris+Polygonum hydropiper association,Hippuris vulgaris+Scirpus validus association and Polygonum hydropiper+Nymphoides peltatum association. Ass.Polygonum tenellum+Heleocharis dulcis had the highest Simpson diversity and the lowest evenness, while the Ass. Polygonum hydropiper+Nymphoides peltatum had the lowest Simpson diversitybut the highest evenness. The results of DCA ordination were consistent with the clustering results, with the first axis interpretation being the largest (53.29%), which reflected the change trend of plant associations’ water level from low to high. The PCA results showed that chemical oxygen demand  and water depth were the key environmental factors affecting the distribution of plant communities. Our results can provide scientific basis for the protection and restoration of Laoshifuhai wetlands.


Spatial distribution relations of main plant populations in eastern Badain Jaran Desert.

LIU Hong-mei, LYU Shi-jie, LIU Qing-quan, LIU Li-ying, WANG Yu-zhi, REN Qian-nan, ZHOU Yao, GAO Qi

2021, 40(4):  959-967.  doi:10.13292/j.1000-4890.202104.016

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Haloxylon ammodendron, Reaumuria songarica, and Nitraria tangutorum are of great significance for wind prevention, sand fixation, and ecoenvironment improvement in Badain Jaran Desert. We explored their spatial distribution and interaction in Tamushu Wild Cistanche deserticolaand Haloxylon ammodendron Seed Production Base in Tamushu Town of Alxa Right Banner. Spatial distribution consistency, patch distribution characteristics, vegetation development direction and density effect of the three species were analyzed from the perspective of spatial distribution. The results showed that the consistency of spatial distribution of H. ammodendron, R. songarica and N. tangutorum decreased in proper order. The patch mosaic of spatial distribution was obvious among different species. The process of population invasion into the sandy land extended from southwest to northeast. Affected by the biological characteristics and resource constraints, the coordinate of runoff curve of average crown diameter was (700, 0), which was closely related to the dominance of H. ammodendronpopulation. There was competition among the three species within the 200 m scale and a synergistic effect in the whole research scale, with the trade off being based on the limitation of soil resources and the severity of the natural environment. In conclusion, there was a spatial mosaic distribution of the three species with smallscale competition and large-scale cooperation, due to their own biological characteristics and ecological adaptation characteristics. The vegetation diffusion pattern and development trend were dominated by H. ammodendron population.

The potential geographical distribution of Alsophila spinulosainunder climate change in China.

ZHANG Hua, ZHAO Hao-xiang, XU Cun-gang

2021, 40(4):  968-979.  doi:10.13292/j.1000-4890.202104.022

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Alsophila spinulosa, a relict plant species of early Tertiary glaciers and one of the oldest living fossils in the world, is of great value for understanding changes in paleoclimate, species evolution, and geographic flora. Based on 111 effective distribution records ofA. spinulosa in China and 10 environmental variables, the MaxEnt model and ArcGIS software were used to predict the potential geographic distribution of A. spinulosa. The relative contribution of comprehensive environmental variables and jackknife method were used to assess the essential factors that restrict the potential geographic distribution of A. spinulosa. Meanwhile, the response curve was constructed to determine the appropriate values of environmental variables as well as the potential geographic distribution location and area of A. spinulosa. Our results showed that the prediction accuracy of the MaxEnt model was high, with the receiver operating curve area (AUC value) reaching 0.959. The total suitable habitat area for the potential geographic distribution of A. spinulosa was 160.15×10⁴ km², mainly located in southern and southeastern China. The main environmental factors affecting the potential geographic distribution of A. spinulosa were temperature factor (mean temperature difference per day and mean temperature of the driest season), precipitation factor (precipitation of the driest season), and topographic factor (slope), with precipitation in the driest season as the most essential one. Under future climate change scenarios, the total area of suitable habitat will increase, the area of highly and moderately suitable habitats will decrease, and the area of lowly suitable habitats will increase. The center of gravity in the highly suitable habitat of A. spinulosa will shift to the northwest and high-latitude regions. Our results provide a theoretical basis for the management and resource protection of A. spinulosa.

Effects of light intensity on the photosynthetic characteristics of Ulmus elongata.

LUO Guang-yu, CHEN Chao, LI Yue-ling, JIN Ze-xin

2021, 40(4):  980-988.  doi:10.13292/j.1000-4890.202104.013

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To explore the photosynthetic adaptation of the endangered species Ulmus elongata to different light conditions, two-year-old seedlings were planted under different shading treatments, i.e. 100% of natural light (I₁₀₀), 40% of natural light (I₄₀), and 10% of natural light (I₁₀). We analyzed the effects of different light intensities on the photosynthetic characteristics of U. elongata. The results showed that: (1) The diurnal variations of the net photosynthetic rate (P_n), stomatal conductance (G_s), and transpiration rate (T_r) of U. elongata under all the three light intensities presented “singlepeak” curves, with a peak at about 12:00. In contrast, the diurnal variation of the intercellular CO₂ concentration (C_i) exhibited a “Vshaped” pattern. The daily mean values of P_n,G_s, and water use efficiency (WUE) under three light intensities ranked as I₁₀₀>I₄₀>I₁₀, while those of C_i ranked as I₁₀>I₁₀₀>I₄₀. The daily mean value of T_r under I₁₀ treatment was significantly lower than that under the I₁₀₀ and I₄₀ treatments. (2) The maximum net photosynthetic rate (P_nmax), light saturation point (LSP), light compensation point (LCP), and dark respiration rate (R_d) of U. elongata seedlings uniformly occurred under I₁₀₀ treatment. Both the maximum carboxylation rate (V_cmax) and triose phosphate utilization rate (TPU) ranked as I₁₀₀>I₄₀>I₁₀. The maximum electron transfer rate (J_max) under I₁₀ treatment was significantly lower than that under I₁₀₀ and I₄₀ treatments. (3) Shading increased PSII maximum photon yield (F_v/F_m) and PSII actual photon yield (F_v′/F_m′). The non-photochemical quenching coefficient (NPQ) and photochemical quenching coefficient (q_p) under I₁₀₀ treatment were significantly higher than those under I₄₀ and I₁₀ treatments. Light energy absorbed by the leaves of U. elongata seedlings in the fulllight environment was dissipated mainly in the form of antenna heat. The majority of light energy in leaves under the shading treatment was distributed to the photochemical reaction and non-photochemical reaction dissipation part, with little remained for antenna heat dissipation. Collectively, there was no obvious photoinhibition in U. elongata under strong light and high temperature, and no photosynthetic “midday break” phenomenon. The carbon assimilation efficiency of U. elongatawas high. These results revealed the characteristics of heliophilous plants. Insufficient light may be a factor inhibiting the natural regeneration of U. elongata seedlings.

Water use of Populus euphratica in different development stages growing near the riverbank at the tail of the Keriya River.

LI Tao, LUO Guang-ming, DONG Ke-peng, PENG Li-ping, DAI Yue, Marhaba·Nijat

2021, 40(4):  989-997.  doi:10.13292/j.1000-4890.202104.014

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Populus euphratica is the main tree species in desert riparian forests, with an important role in regulating climate, fixing sand, stabilizing river channel, and maintaining the stability of oasis community. In this study, we investigated P. euphratica near the riverbank at the tail of the Keriya River in the hinterland of Taklimakan Desert in northwestern China. Based on diameter at breast height (DBH), P. euphratica individuals were classified into four development stages, i.e., seedling (Basal diameter≤4 cm), sapling (4 cm<DBH≤10 cm), mature tree (10 cm<DBH≤40 cm), and overmature tree (DBH>40 cm). We measured oxygen stable isotope ratios (δ¹⁸O) in xylem water, soil water in different soil layers (0-300 cm depth), groundwater, and river water. Four potential water sources were classified: shallow soil water (0-140 cm), deep soil water (140-300 cm), groundwater, and river water. The ratios of different potential water sources used by P. euphratica were determined using the IsoSource model. Stable carbon isotope technology was used to examine the water use efficiency ofP. euphratica in different development stages. The result showed that δ¹⁸O value of xylem water of P. euphratica decreased with DBH, with a range of -6.10‰ to -5.67‰. Seedling, sapling, mature tree, and overmature tree of P. euphratica mainly used river water, with corresponding water use ranges of 0-74%, 0-77%, 7%-80%, and 17%-82%, respectively. Foliar δ¹³C of P. euphratica changed slightly with increasing DBH, ranging between -29.96‰ and -29.02‰. Our findings suggested that P. euphratica growing near the riverbank at the tail of the Keriya River have good water conditions and suffer little drought stress.

Effects of N, P, and K fertilization on nutrient uptakes and utilizations of Phoebe bournei seedlings.

YANG Zhi-jian, FENG Jin-ling, WU Xiao-hui, CHEN Lai-he, YU Xin-xiao, CHEN Li-hua

2021, 40(4):  998-1011.  doi:10.13292/j.1000-4890.202104.017

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Phoebe bournei is an endangered but precious timber species. In a field pot experiment with “3414” incomplete orthogonal regression design, we examined the effects of N, P and K fertilizers on the nutrient uptake and utilization of one-year-old P. bournei rootnaked seedlings, with the aim to explore the interaction of nutrient elements and their effects on the growth ofP. bournei seedlings. The effects of different N, P, and K fertilizations on dry matter growth and nutrient element uptakes and utilization were examined. The results showed that appropriate N, P and K fertilization promoted dry matter, N, P and K uptakes and C fixation of P. bourni seedlings. All those variables showed the trend of first increasing and then decreasing with the increasing fertilization rate, with the maximum at T6 treatment (N, 0.532 g·plant^-1; P₂O₅, 0.133 g·plant^-1; K₂O, 0.356 g·plant^-1; N∶P₂O₅∶K₂O=1∶0.250∶0.669). Nitrogen fertilization had the strongest effect on the growth ofP. bournei seedlings, followed by K fertilization and P fertilization. Nitrogen fertilization promoted C fixation and dry matter growth by increasing N uptake, and further improved P and K uptakes. Phosphorus fertilization enhanced dry matter accumulation and nutrient uptake, but did not affect P utilization. Potassium fertilization mainly promoted seedlings growth by affecting P uptake and utilization. The NPK combined fertilization had the strongest positive effect on seedling growth, followed by twofactor fertilization and singlefactor fertilization. The NK fertilization was beneficial to nutrient uptake, while NP fertilization was beneficial to nutrient utilization. The T6 treatment was the best fertilization rate and proportion. By principal component and path analysis, we found that increasing utilization rate of N and K fertilizers and the C fixed amount which were subjected to the balance of P uptake and utilization, could promote the seedling growth. Therefore, N and K agronomic efficiency was the key index for the fertilization of P. bournei seedlings. P. bournei seedlings preferred N to P. The NPK fertilization was beneficial to the nutrient uptake and utilization of P. bournei seedlings, with the T6 treatment being the best one.

Effects of nitrogen topdressing on photosynthesis and yield formation of winter wheat under straw mulching.

YANG Chao, FU Xin, LIU Wen-qing, WANG Jun

2021, 40(4):  1012-1020.  doi:10.13292/j.1000-4890.202104.032

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Based on a long-term straw mulching experiment with micro-plot fertilization in the dryland winter wheat monoculture system, we investigated the effects of nitrogen topdressing on photosynthesis and yield formation. There were four treatments, including no mulching as control (CK), straw mulching at rates of 9000 (HSM) and 4500 kg·hm^-2 (LSM) during growing season, and at a rate of 9000 kg·hm^-2 during summer fallow (FSM). Topdressing was applied at the booting stage. Without topdressing, soil NO₃^--N and NH₄⁺-N concentrations were lower under HSM and LSM than under CK. Leaf photosynthesis rate, stomatal conductance, transpiration rate, and water use efficiency were lower under HSM, LSM and FSM than that under CK. Wheat grain yield was lower by 28.43% and 21.74% under HSM and LSM than under CK (P<0.05), respectively. With topdressing, soil NO₃^--N and NH₄⁺-N concentrations and photosynthetic characteristics of winter wheat flag leaves in HSM, LSM and FSM treatments were significantly higher than those without topdressing. There was no significant difference in wheat thousand-grain weight, aboveground biomass, grain yield, and harvest index among all the treatments. Ourresults indicate that nitrogen topdressing at late growing stage of winter wheat would be a reliable measure to solve soil nitrogen deficit caused by straw mulching, promote leaf photosynthesis after anthesis, and reduce the potential risk of yield reduction resulted from straw mulching.

The variation of rhizosphere microorganisms of replanted Casuarina equisetifolia plantations mediated by phenolic acids.

ZHOU Liu-ting, LUO Yang, LI Jian-juan, ZHAO Yan-lin, BAI Ying, ZHANG Chen, CHEN Jun, LIN Wen-xiong, WU Ze-yan

2021, 40(4):  1021-1028.  doi:10.13292/j.1000-4890.202104.004

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We examined the species and content of phenolic acids in rhizosphere soil of replanted Casuarina equisetifolia plantations (including first rotation plantation (FCP), second rotation plantation (SCP) and third rotation plantation (TCP)) in Fujian Huian Chihu State-owned Shelter Forest Farm by high performance liquid chromatography (HPLC). The ratio of phenolic acids in rhizosphere soil was simulated to explore its effect on the growth of key soil microbes. The results showed that five kinds of phenolic acids were detected in the root exudates of C. equisetifolia, including vanillic acid, ferulic acid, gallic acid, cumaric acid, and salicylic acid, with an average ratio of 32∶6∶19∶5∶8. The total content of phenolic acids increased with increasing rotation generations. Among the five phenolic compounds, vanillic acid, gallic acid, cumaric acid, and salicylic acid accumulated in SCP and TCP, while the content of ferulic acid showed a decreasing trend with increasing rotation generations (P>0.05). The phenolic acids mixture at their ratios explored in the C. equisetifolia soil significantly accelerated mycelial growth of Fusarium oxysporum, but inhibited Bacillus amyloliquefacien. Salicylic acid had the strongest positive or negative effects on the growth of pathogenic or beneficial microorganisms. Therefore, the mixture of phenolic compounds played a role in affecting the growth of soil microorganisms, resulting in the structure imbalance of rhizosphere microbial community, and consequently leading to consecutive planting obstacles. Our results provide a theoretical reference for alleviating consecutive planting obstacles in the production and management of C. equisetifoliaplantations.


Effects of nitrogen deposition on soil respiration and its sensitivity to temperature and humidity in a Quercus acutissima forest in northern subtropics.

YU Jing-song, FU Ruo-xian, YU Yuan-chun, LI Chun-tao, TAO Xiao

2021, 40(4):  1029-1037.  doi:10.13292/j.1000-4890.202104.019

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In recent years, emissions of nitrogenous compounds have increased rapidly, which would continue with population growth and urbanization. Such nitrogen falls into forest ecosystems in the form of deposition, with profound impacts on forest soil carbon fluxes. Nitrogen deposition becomes an important factor affecting forest soil respiration. In this study, a nitrogen deposition simulation experiment was carried out in a Quercus acutissima natural forest in Wanfo Mountain, Anhui Province to explore the shortterm impacts of nitrogen addition on soil respiration and components and their sensitivity to temperature and humidity. The soil respiration rate, soil temperature and moisture were measured by LI-8100. Soil respiration and its components had obvious seasonal variations under all the treatments of N0 (control), N1 (low N) and N2 (high N). Both N1 and N2 treatments slightly increased total soil respiration and its components, but without statistical significance (P<0.05). The average annual total soil respiration rates of N0, N1, and N2 treatments were 2.03, 2.17 and 2.13 μmol·m^-2·s^-1, with 6.90% and 4.93% higher in N1 and N2 treatments than in N0 treatment, respectively. There was a significant exponential relationship between soil respiration and soil temperature (P<0.001). The Q₁₀ values of the total soil respiration under N0, N1 and N2 treatments were 2.04, 1.99 and 2.10, respectively. N1 treatment increased the Q₁₀ of the autotrophic respiration but decreased the Q₁₀ of the heterotrophic respiration. N2 treatment increased the Q_10 of each component of soil respiration. There was a significant correlation between soil moisture and soil respiration (P<0.05), with the R² value of its correlation being smaller than that between soil temperature and soil respiration. The composite model of soil respiration with soil temperature and soil moisture performed better than the singlefactor models. Our findings provide a new way to predict the changes of soil respiration and its components under the increasing nitrogen deposition scenarios.

Effects of simulated warming on soil respiration in growing season in an alpine scrubland.

LIU Mei, CHEN Ya-mei, CUI Ning-jie, MA Zhi-liang

2021, 40(4):  1038-1048.  doi:10.13292/j.1000-4890.202104.026

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An in situ opentop chamber (OTC) experiment was conducted to investigate the effects of climate warming on soil respiration in the growing season ofSibiraea angustata alpine scrubland on the eastern Qinghai-Tibet Plateau. The results showed that the simulated warming increased the average temperature of air and soil by 0.6 ℃ and 1.2 ℃, respectively, and decreased soil moisture by 2.7 percents. Simulated warming significantly increased the rates of total soil respiration and all its components. The rates of total soil respiration, heterotrophic respiration, rhizosphere respiration, fine root respiration and rhizomicrobial respiration were increased by 54.3%-99.2%, 60.8%-80.3%, 30.0%-165.0%, 37.6%-110.1% and 96.7%-215.3%, respectively. Soil enzyme activities, soil temperature and soil pH were the main contributors to the changes of the rates of soil respiration components, which explained more than 49.2% variations of soil respiration rates. There was no significant effect of soil microbial biomass, soil inorganic nitrogen content and soil moisture on the rates of soil respiration components. The rates of rhizosphere respiration and fine root respiration were positively correlated with fine root biomass. These results indicated that global climate warming could promote soil respiration of alpine scrub ecosystem on the eastern Qinghai-Tibet Plateau by changing biotic and abiotic factors, and thus accelerate soil carbon cycling.

Short-term effects of tending thinning on soil labile organic carbon in Pinus massoniana stands.

WANG Xiao-rong, LEI Lei, ZENG Li-xiong, TANG Wan-peng, CUI Hong-xia, XIAO Wen-fa

2021, 40(4):  1049-1061.  doi:10.13292/j.1000-4890.202104.008

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Quantifying the variations of soil labile organic carbon in Pinus massoniana stands with different forest management practices is of great significance for understanding the impacts of forest management strategies on soil carbon pool. In this study, we examined the impacts of forest managements, including no-cutting (NC), shrubs cutting (SC), nonP. massoniana cutting (NPMC) and dominant P. massoniana cutting (DPMC), on soil labile organic carbon in P. massoniana air seeded stands in the Three Gorges Reservoir Area. We used equidistant grid point sampling method to measure the content and spatial heterogeneity of soil labile organic carbon in topsoil (0-10 cm) and used multiple linear regression model to detect the main driving factors. Our results showed that total organic carbon (TOC) content and microbial biomass carbon (MBC) were significantly lower in SC, NPMC, and DPMC plots than those in NC plot, while the content of soil light fraction organic carbon (LFOC) showed no significant variation. Compared with the NC treatment, the dissolved organic carbon (DOC) content increased by 21.68% under NPMC and increased by 19.90% under DPMC treatment, while it decreased by 7.06% under SC treatment. The variation of all soil organic carbon fractions in NC and DPMC plot had a weak spatial autocorrelation. The variation range of soil organic carbon fractions such as TOC, DOC and MBC caused by structure factors was 69.5%-98.5% in SC plot, and that of TOC, DOC, and LFOC was 94.5%-99.7% in NPMC plot. All managements increased the spatial heterogeneity of soil labile organic carbon. The main factors affecting spatial variation of soil labileorganic carbon were soil total organic carbon, total nitrogen, carbon/nitrogen ratio, diameter at breast height of trees, leaf area, and soil moisture. These results indicated that the tending thinning practices including understory removal and selective cutting measures can affect soil organic carbon and increase the instability of soil organic carbon by changing stand structure, soil physical and chemical properties, and microenvironment.

Effects of no-tillage and straw mulching on carbon, nitrogen, and phosphorus ecological stoichiometry in spring wheat and soil.

PENG Ya-min, WU Jun, CAI Li-qun, QI Peng, ZHANG Ren-zhi, LUO Zhu-zhu

2021, 40(4):  1062-1072.  doi:10.13292/j.1000-4890.202104.028

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To provide reference for formulating reasonable management measures in the dry farming area of Longzhong Loess Plateau, we explored the effects of no-tillage and straw mulching modes on carbon (C), nitrogen (N), and phosphorous (P) ecological stoichiometry in spring wheat and soil. Based on the long-term conservation tillage \[conventional tillage (T), notillage with no straw mulching (NT), conventional tillage with straw incorporation (TS), no-tillage with straw mulching (NTS)\] positioning experiment set in Mazichuan Village, Lijiabao Town, Anding District, we measured C, N, and P concentrations in different spring wheat organs (i.e., grain, leaf, straw) and soil in 2019. The results showed that compared with conventional tillage (T), conservation tillage treatments (NT, TS, and NTS) significantly increased soil C∶N and C∶P (P<0.01), but did not affect N∶P (P>0.05). The magnitude of C∶N and C∶P changes among different treatments was in the order of NTS>TS>NT>T. The order of C∶N for different organs of spring wheat was straw>leaf>grain, and the order of C∶P was grain>leaf>straw. Compared with T treatment, conservation tillage treatments significantly reduced leaf C∶N, straw C∶N and C∶P, whereas N∶P in each organ showed no variation among different treatments (P>0.05). The growth of spring wheat in this area was limited by N availability. The overall internal stability of C, N and P of spring wheat and the soil was P>N>C, the ratio internal stability was C∶N>C∶P>N∶P, and the internal stability of element ratio was stronger than that of each element. In short, NTS treatment is the most suitable farming measure for spring wheat growth and development in the dry farming area of the Longzhong Loess Plateau. The growth of spring wheat in this area is susceptible to N limitation. Nitrogen fertilizer application should be appropriately increased based on NTS treatment to ensure the growth of spring wheat.

Effects of combined application of organic fertilizer on the active components of organic carbon in upland purple soil under reducing chemical fertilizer application.

KONG De-ning, KANG Guo-dong, LI Peng, SHEN Xue-shan, LIU Man-qiang, LI Hui-xin, HU Feng, JIAO Jia-guo

2021, 40(4):  1073-1080.  doi:10.13292/j.1000-4890.202104.002

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We explored the effects of different organic compounds on soil organic carbon active components under the condition of reduced fertilizer application in purple soil in Sichuan, under purple potato and Solanum tuberdsm rotation system. There were seven treatments, including no fertilization (CK), conventional fertilizer (CF), conventional fertilizer with straw (CFS), reduced 50% fertilizer with microbial organic fertilizer (RFM), reduced 50% fertilizer with earthworm biological compound organic fertilizer (RFV), reduced 50% fertilizer with straw and microbial organic fertilizer (RFSM), reduced 50% fertilizer with straw and earthworm biological compound fertilizer (RFSV). The results showed that the application of organic materials did not affect soil total organic carbon content, but significantly increased microbial biomass carbon (MBC) and the content of labile organic carbon (LOC) by 10.6%-42.6%. The results of three-dimensional fluorescence analysis of soil dissolved organic carbon (DOC) showed that humic acid and furitic acid were the main components of DOC in purple soil. Under the treatments of RFSM and RFSV, the contents of humic acid and furitic acid increased, while tryptophan, tyrosine and soluble microbial metabolites decreased. The three-dimensional fluorescence index increased, indicating that DOC was mainly derived from the metabolic activities of microorganisms. In conclusion, organic fertilizer addition under reduced chemical fertilizer application could increase MBC and LOC content and change the component structure of DOC.

Effects of nitrapyrin application on nitrogen transformation in red soil under different fertilization schemes.

LI Jun, ZHAO Xi-ran, WANG Xin-long, WU Xiao-liang, GUO Jia-xin, HU Zhong-yue, CHU Gui-xin, TAO Rui

2021, 40(4):  1081-1090.  doi:10.13292/j.1000-4890.202104.030

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The objective of this study was to examine the effects of combined application of organic manure and nitrapyrin (CP) on nitrogen transformation, N₂O and NH₃ emissions, and ammonia-oxidizing bacteria and archaea (AOA and AOB) in red soil. An incubation experiment was carried out with five treatments, including no fertilization (CK), only urea, urea + CP, 60% urea + cattle manure, and 60% urea + cattle manure + CP. The results showed that the nitrapyrin addition treatments significantly increased soil NH₄⁺-N concentration and reduced NO₃^--N concentration within 36 days after incubation (P<0.05) compared to only urea and 60% urea + cattle manure treatments. Urea or urea plus manure treatment significantly increased soil potential nitrification rate and microbial biomass carbon and nitrogen (P<0.05) at seven days after incubation, which were significantly decreased by the addition of nitrapyrin. qPCR results showed that urea combined with manure application significantly increased both AOA and AOB gene abundance, while nitrapyrin application significantly reduced the gene abundance of AOA rather than that of AOB. The AOA abundance in nitrapyrin addition treatment recovered to the level in no nitrapyrin treatments at 36 days of incubation. Soil potential nitrification rate was significantly correlated with AOA and AOB (P<0.001). Reduced urea combined with manure application significantly reduced N₂O and NH₃ emissions compared with urea application alone during the  incubation, while the addition of nitrapyrin further significantly reduced N₂O emissions but increased NH₃ emissions. NH₄⁺ and pH were the key factors affecting the abundance of AOA and AOB gene. AOA contributed more to N₂O emissions than AOB in this red soil. In conclusion, nitrapyrin combined with urea or organic manure application could mitigate N₂O emission, but increase the risk of NH₃ volatilization.

Overlapping barrier and avoidance effects of the Qinghai-Tibet highway and railway on four typical ungulates on the Tibetan Plateau.

WANG Yun, GUAN Lei, DU Li-xia, QU Jia-peng, WANG Ming-yue, HAN Yong-shun, YANG Yan-gang, ZHOU Hong-ping, KONG Ya-ping

2021, 40(4):  1091-1097.  doi:10.13292/j.1000-4890.202104.015

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Previous studies reported that the Qinghai-Tibet highway or railway had barrier effects on the migration of the Tibetan antelope (Pantholops hodgsonii) and other endemic species on the Tibetan Plateau. However, no study has focused on the overlapping barrier effect of those two transportation routes. Here, we analyzed the data of avoidance distance caused by road traffic disturbance of four typical ungulates in 2006-2008 and 2010  combined with field monitoring data during 2014 to 2019. Among the four species, there was an overlapping barrier effect only on the Tibetan antelope, the magnitude of which lessened with increased distance between the two transportation routes. The adaptation period (i.e., the amount of time it takes wildlife avoidance of the highway to reach a stable level) of Tibetan antelope along the highway was about four years, while the adaptation period for both Tibetan gazelle (Procapra picticaudata) and kiang (Equus kiang) was about two years. Traffic volume did not affect the avoidance distance of those four ungulates. A new expressway will be built parallel to the existing highway and railway. Based on existing knowledge, the distance between the expressway and the existing highway and railway should be at least 1.5 km to accommodate the migration of Tibetan antelopes. Although the four ungulate species could adapt to the presence of the highway, reducing human disturbance would still be beneficial. For example, creating undulating terrain and designing measures that screen vehicle lights and block traffic noise would help mitigate the impacts of expressway on the migration of Tibetan antelope. It is needed to monitor wildlife activity prior to, during, and after the construction of expressway.

The daily vocal pattern of   Adélie penguin during brooding period in the polar day.

ZHANG Jian, XIA Can-wei, ZHANG Yan-yun

2021, 40(4):  1098-1106.  doi:10.13292/j.1000-4890.202104.018

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Daily rhythms enable organisms to adapt to the daily fluctuations of environmental factors. There is a debate on whether organisms would exhibit 24h rhythms when living in habitats without obvious daily cycles of external signals. To answer this question, we investigated the daily vocal pattern of Adélie penguins (Pygoscelis adeliae) breeding on Inexpressible Island (74°54′S, 163°39′E). Adélie penguins use calls to contact with their chicks during the brooding period. Recordings were made using five passive acoustic recorders during January 24th to February 1st, 2018. Calls were detected through automatic recognition. The daily rhythm and the relationship between the intensity of calls and environmental factors were studied. There was no prevailing daily vocal pattern. Vocal activity was positively related with environmental humidity and temperature. Our results would help understand the behavior rhythm in the polar day.

Species diversity and genetic relationship of dung beetle in Seirphidium dominated desert.

CAO Jia-min, LU Wei-hua, GUO Ya-ya, CHE Zhao-bi, YANG Han-jun, HUANG Xing-yu

2021, 40(4):  1107-1115.  doi:10.13292/j.1000-4890.202104.009

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Seirphidiumdominated desert, widely distributed in northern Xinjiang, bears grazing pressure in both spring and autumn. Due to the dry climate, the decomposition of feces of grazing livestock strongly depends on dung beetles. In this study, we recorded the seasonal variation and species diversity of dung beetles in the Seirphidiumdominated desert grassland. A total of 14797 dung-eating insects were captured, belonging to 19 species and 3 families, in which there were 10 species from Aphodiidae, 8 species from Scarabaeidae, 1 species from Geotrupidae. The species richness gradually increased from April to June. The dominant species was Aphodius sublimbatus. The beetle abundance in spring and autumn grazing season (April to May, September to October) was greater than that in summer (July to August). The species richness was the lowest in October, but the abundance of the dominant species Aphodius rectus was significantly higher than that of all other species. The results of 16S rRNA based classification were consistent with morphological classification. The established evolutionary tree was divided into two distinct branches. The first branch contained 10 Aphodiinae species, which belonged to Dweller. The fecal disposal of species has obvious convergence. The second branch included nine species of Scarabaeidae and Geotrupidae. From the perspective of functional groups, there are seven Tunnelers and two Rollers. Although Onthophagus gibbulus, Onthophagus nuchicornis,Gymnopleurus mopsus, andGymnopleurus flayellates have close genetic relationship, they were belonged to two functional groups and showed interspecific divergence in fecal disposal.

Assessment of macrozoobenthos habitat suitability in the upper and middle reaches of the Heihe River.

WANG Yu, ZUO Yi-feng, FENG Qi, LI Bao-long, KONG De-xing, ZHANG Xin-yu, LU Han, WANG Shuang

2021, 40(4):  1116-1127.  doi:10.13292/j.1000-4890.202104.010

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We assessed the habitat suitability of macrobenthos in the upper and middle reaches of the Heihe River, with the dominant species Argyroneta aquaticaas the indicator species. Three indicator factors, including dissolved oxygen (DO), water temperature (WT), and sediment (SD), were selected from the habitat environmental factors. The habitat suitability curves of the three indicator factors were established, and the habitat suitability index (HSI) of A. aquatica at each site was calculated. The results showed that A. aquatica prefers pebble riverbeds, with the ranges of optimum dissolved oxygen (DO) concentration being 7.21-9.17 mg·L^-1, and the range of optimum water temperature (WT) being 17.25-22.10 ℃. The average HSI values in the upper and middle reaches of the Heihe River were 0.66 for the upper tributary, 0.63 for the upper mainstream, and 0.81 for the middle reaches. The upper tributary and upper mainstream reaches of Heihe River were under a suitable state, and the middle reaches were under the most suitable state for macrozoobenthos. Results of spatial variability analysis showed that human activities had little impact on the habitats of macrozoobenthos in the upper tributary and middle reaches of the Heihe River. Water temperature was the main factor restricting the habitat suitability of the upper tributary. The construction of cascade reservoir was an important factor affecting the habitat of macrozoobenthos in the upper reaches of Heihe River.


Screening of a low-temperature cellulose-degrading bacterium and optimization of cellulase production conditions.

SHAN Jian-rong, QUAN Xin, ZHU Yong-zhe, XING Yu, ZHANG Xu, WANG Hong-yan, FAN Jin-xia

2021, 40(4):  1128-1136.  doi:10.13292/j.1000-4890.202104.005

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An effective solution to resolve the problems of slow start of cow manure composting and long fermentation cycle in winter is the addition of lowtemperature cellulose-degrading microbe to the pile. However, few types of low-temperature cellulose-degrading microbe are available. In this study, one low-temperature and high-efficiency cellulose-degrading strain was isolated from frozen cow dung under low temperature conditions, which was named YSX-3. It was identified as Pseudomonas. In order to obtain its optimal enzyme production condition, on the basis of single factor optimization, incubation time, incubation temperature, initial pH value and inoculum amount are considered as independent variables, and cellulase activity as the response variable. Response surface analysis (RSM) was used to analyze the relationship between response variable and the independent variables. The results showed that the optimal enzyme production condition of YSX-3 strain was as follows: inoculating amount 4%, culture temperature 9 ℃, culture time 71 h and initial pH 6.5. Under this condition, the cellulase activity was 130.21 U·mL^-1, which was 1.3 times higher than that before optimization. The optimized YSX-3 strain was inoculated into the manure pile. On the fifth day, the high-temperature period came (>50 ℃), the temperature reached up to 62.5 ℃, and the high temperature period lasted for nine days. At the end of composting, the degradation rate of cellulose reached 45.2%, while that in the control group was only 15.4%.

Spatiotemporal dynamics of mariculture area in Sansha Bay and its driving factors.

CHEN Si-ming

2021, 40(4):  1137-1145.  doi:10.13292/j.1000-4890.202104.033

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Based on data derived from Landsat multitemporal remote sensing images, the feature index and object-oriented classification were combined to extract the spatial information of mariculture area in Sansha Bay of Ningde, Northeast Fujian. Landscape pattern index and random forest algorithm were used to analyze the spatial and temporal expansion and morphological characteristics of mariculture areas, and to quantify the effects of natural, social, and economic factors on the spatial and temporal variations of mariculture areas. The results showed that object-oriented classification had a good outcome, with the total accuracy and Kappa coefficient being more than 81% and 0.72, respectively. During 2009 to 2018, patch area, patch density, and landscape shape index showed a trend of first increase and then decrease. The spatial aggregation of mariculture area was increasing, displaying the aggregation characteristics of the continuous block distribution from west to northeast. The spatiotemporal dynamics of mariculture area were mainly affected by the gross fishery production, the mean annual income of employees (agricultural, forestry, animal husbandry, sideline and fishery), the number of fishing motor boats, and the mean annual wind speed. The gross fishery production and the mean annual income of employees were more important in shaping landscape pattern, with a determination coefficient (R²) of 0.77. Our results can serve as a theoretical basis for culture zone planning and ecological environment protection in Fujian coastal areas.

 

Climate yield simulation of juicy peach in Fenghua based on disaster index.

DING Ye-yi, YANG Dong, ZHU Jia-min, CHEN Miao-jin, LI Cong-chu, WEI Sha-sha, XU Hong-xia

2021, 40(4):  1146-1153.  doi:10.13292/j.1000-4890.202104.031

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Climate yield simulation is critical to the insurance design and benefit evaluation of meteorological service for agriculture. Based on the peach yield data in Fenghua from 1995 to 2018, Fourier transform, moving average, Logistic, HP filter and exponent methods were used to separate the trend yield and climate yield of juicy peach. The common meteorological disaster index of juicy peach was established, which was used to verify and screen the yield separation results with five different methods. With the disaster index as the input factor, the climate yield model of peach was established by BP neural network based on genetic algorithm (GA-BP). The results showed that, from 1995 to 2018, the continuous rain during blossommature period and heavy precipitation during stone hardeningmature stage of Fenghua juicy peach decreased first and then increased. In recent years, the frequency of extreme precipitation and gale increased. Climate warming alleviated the chilling damage in flowering and fruit setting stage, but increased the risk of high temperature in mature stage. The simulation effect of trend yield by the third-order Fourier separation was good. The simulation accuracy of typical disaster years and low disaster years was as high as 88%, with a correlation coefficient of -0.8 and a comprehensive index of0.85. The GABP model based on the disaster index had the best simulation effect on the relative climate yield separated by the thirdorder Fourier method. The absolute error and root mean square error of the back-testing were 0.02 and 0.03, respectively, with the correlation coefficient being as high as 0.95. The absolute error and root mean square error of prediction test were 0.03 and 0.04, respectively, with the correlation coefficient being as high as 0.92. In conclusion, the thirdorder Fourier method was suitable for peach yield separation in Fenghua. The simulation accuracy and stability of characteristic crop yield based on disaster index were higher, with clear physical meaning of the model.

Ecological quality evaluation and influencing factors analysis of Helan Mountain based on RSEI.

LI Ting-ting, MA Chao, GUO Zeng-chang

2021, 40(4):  1154-1165.  doi:10.13292/j.1000-4890.202104.027

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We analyzed the relationship between ecological quality change and climate and topography in Helan Mountain from 1989 to 2017, with multitemporal Landsat data, RSEI (remote sensing ecological index), SRTM DEM data, Chinese meteorological data and spatial distribution data of vegetation types. The RSEI obtained by coupling WET, NDVI, SI and LST could comprehensively reflect ecological quality, with the load value of NDVI being the highest. From 1989 to 2017, the average value of RSEI in the study area showed an uptrend, with a range of 0.2849-0.3671 and an annual growth rate of 0.0058. The RSEI-improved area was 14.6 times of the RSEI-degraded area. The excellent and good levels of RSEI were mainly distributed in forest areas, while the variation coefficient of eco-environment in these regions was small. The moderate, low and poor grades of RSEI were mainly distributed in desert and grassland covered areas, which were mainly the areas of ecoenvironment improvement. A total of 9.29% areas with correlation between RSEI and temperature passed the significance test (P<0.05), and 12.51% of the areas with correlation between RSEI and precipitation passed the significance test (P<0.05). Theresponse of RSEI to precipitation was stronger than that to temperature. The best ecological quality area of Helan Mountain was located in altitude 2500-3000 m and slope 35°-40°. Although the ecological environment of Helan Mountain is slowly getting better, the overall ecological quality is still extremely fragile. There is still a long way to go for ecological protection in this area.

The structure and grain size of wind-sand flow in the dry bottom of Qingtu Lake.

GUO Shu-jiang, YANG Zi-hui, WANG Qiang-qiang, WANG Duo-ze, WANG fei, AN Fu-bo, ZHANG Yi-jun, LI Yi-jun, WANG Ming-guo

2021, 40(4):  1166-1176.  doi:10.13292/j.1000-4890.202104.025

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We monitored the structure of wind-sand flow in nine types of sites in the dry bottom of Qingtu Lake by sand accumulation instrument and analyzed the variations of sediment transport rate, grain size composition and grain size parameters of windsand flow at the height of 0-30 cm in different sites. The results showed that the sediment transport rates and fluxes of seven site types had negative power function relationship with height of 0-30 cm. The sediment transport fluxes of different sites were mainly concentrated in the nearsurface area of 0-20 cm height. Except for fixed-dune Nitraria tangutorum shrub, the sediment transport fluxes of other types accounted for more than 80% of the total sediment transport fluxes at the 0-30 cm height. The sand transport rates of wind-sand flow were high in the height range of 0-30 cm among lake shoal,Kalidium foliatumcommunity in lakebed, and moving-duneNitraria tangutorum shrub. The grain content of wind-sand flow in the three types of sites with higher sand transport rate was mainly composed of fine sand, followed by coarse sand and silt. With increasing height, the content of coarse sand in the three types of sites increased slightly at first and then decreased, while the content of fine sand decreased slightly at first and then increased, and the content of silt increased slightly. The grain size classification of the three types of sites was under the levels of good moderate. The skewness value shifted from near symmetry to positive deviation with the increasing height, while the kurtosis value belonged to medium kurtosis distribution.

Evaluation of eco-environmental quality in Mentougou District of Beijing based on improved remote sensing ecological index.

CHENG Lin-lin, WANG Zhen-wei, TIAN Su-feng, LIU Ya-tong, SUN Meng-yao, YANG Yu-man

2021, 40(4):  1177-1185.  doi:10.13292/j.1000-4890.202104.021

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Based on data derived from Landsat images in 2001, 2006, 2010, 2014, and 2018, we calculated the weight of selected indices using the entropy weight method and  the remote sensing ecological index (RSEI) using the index weighted sum method. Combined with GM (1,1) model, we analyzed the dynamics of eco-environmental quality and its causes in Mentougou District of Beijing and predicted the future trend. The results showed that the RSEI of Mentougou in 2001, 2006, 2010, 2014 and 2018 were 0.5993, 0.5451, 0.5592, 0.6113 and 0.716, respectively, displaying a trend of “decline first and then rise”. The areas with “excellent” and “good” eco-environmental quality were mainly forestland and shrub land. “Inferior” and “poor” areas were dominated by bare land, urban land use and roads. Mining activity was the main cause for the decline of RSEI from 2001 to 2006. Since 2006, urbanization had negative impacts on the eco-environmental quality of Mentougou District. Some key projects had improved the ecoenvironmental quality. The Beijing-Tianjin sandstorm source control project had a remarkable positive effect on the eco-environmental quality of Mentougou. The visual expression of eco-environmental quality can better reflect the changes of eco-environmental quality and provide better support for the maintenance of ecological balance.

Research progress on archaea in the estuary.

TANG Yi, YUE Yi-hong, CAI Ling, CHEN Xue-ping, YANG Ming, WANG Fu-shun

2021, 40(4):  1186-1197.  doi:10.13292/j.1000-4890.202104.007

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As an important component of the ecosystem, archaea play a crucial role in driving earth’s biogeochemical cycles. The estuary is a unique geographical transition zone located at the confluence of rivers and oceans. The esturay is considered as a natural testing ground for the study of the structure and diversity of archaeal communities, owing to its complex and changing hydrological environment. Here, we first introduced the development history and technical methods for archaeal research, including lipid structure analysis, fluorescence in situ hybridization, fluorescence quantitative PCR, and high-throughput sequencing. Then, we summarized the research progress on archaea in the estuary, as well as the main factors driving their distribution and community structure in estuaries, such as latitude, salinity and water depth. In addition, the ecological functions of several important archaea groups including ammonia oxidizing archaea, Bathyarchaeota and methanogenic archaea in the estuary were introduced. Finally, we proposed several future research directions of archaea in the estuary. A comprehensive understanding of the functions of the archaeal community in the estuary would be beneficial to the protection and the sustainable development of the estuary ecosystems.

Research progress on the technique of fish attracting in fishway entrance.

TAN Hong-lin, TAN Jun-jun, SHI Xiao-tao, LI Zhen, KE Sen-fan, LIU Zhi-xiong

2021, 40(4):  1198-1209.  doi:10.13292/j.1000-4890.202104.029

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Reasonable setting of fishway entrance is the key to design and construction of fishway. Different environmental conditions affect swimming behaviors of fish. Reasonable utilization of environmental factors (flow, sound, light and bubble curtains) plays an important role in improvingthe efficiency of fish attraction in fishway. This review focused on the techniques of flow, sound, light and bubble curtains, summarized the main factors affecting the techniques of fish attracting and the related research results of fish behaviors. The previous studies on fish attraction mainly focus on the theoretical basis, but have been seldom applied in practical engineering. Therefore, there is an urgent need to reinforce the field application of various techniques of fish attracting and establish comprehensive techniques of fish collecting and attracting, including flow, sound, light, and bubble curtains. These efforts will facilitate improving the efficiency of fish collecting and attracting on fishway entrance.

Adsorption behavior and removal mechanism of biochar on exogenous antibiotics and antibiotic resistance genes.

AN Jing, GAO Cheng-cheng, WANG Bao-yu, YAN Xiu-xiu, WEI Shu-he

2021, 40(4):  1210-1221.  doi:10.13292/j.1000-4890.202104.006

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In recent decades, antibiotics have been extensively used in the fields of health care and animal husbandry. As a result, antibiotic residues and antibiotic resistance genes (ARGs) have been detected in various natural conditions across the world, including livestock manure, natural soil, and water body, posing high risks to environment and human health. Given the current difficulties in regulating discharge of antibiotics, an effective method to reduce the pollution of antibiotics and ARGs in the environment is critical to mitigate their ecological risks. Biochar is a carbon-rich product, with large specific surface area, profound pore structure, abundant functional groups, and low cost. It is considered as an ideal material for removing these pollutants of antibiotics. We systematically summarized the behaviors of biochar in removing antibiotics and ARGs under different environmental conditions, with an emphasis on the enhancement effects of the modified biochar. The adsorption behavior and removal mechanism of biochar to antibiotics and ARGs were also discussed. Furthermore, we proposed the optimization in biochar preparation and adsorption process based on its drawbacks.

Evaluation on the planning and construction of ecological transportation system in Sino-Singapore Tianjin Eco-city based on AHP.

DONG Xiao-feng, ZHANG Ya-juan, ZHANG Qi, SHI Pei-yi

2021, 40(4):  1222-1232.  doi:10.13292/j.1000-4890.202104.035

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The Sino-Singapore Tianjin Eco-city is the sign of the start of eco-city planning and construction in China. Since its completion of the planning in 2007, the occupational-residential comprehensive function zone with the characteristics of low-carbon and ecologicalization as the core of the ecocity has been constructed for more than ten years. The evaluation of its construction effectiveness is of great significance for subsequent construction and optimization of eco-city development model. As an important aspect of eco-city, ecological transportation is an important content of eco-city construction evaluation. Here, we assessed the construction of ecological transportation system in the Sino-Singapore Eco-city. Based on the connotation of ecotraffic, two models, AHP and Delphi, were chosen as the basic evaluation methods. We constructed evaluation index systems of urban ecological transportation, including travel mode, travel convenience, travel environment, social environment, and spatial layout. We collected data on the objective construction progress of typical subjects of the Sino-Singapore Tianjin Ecocity in 2017 and 2020, and conducted a questionnaire survey on the satisfaction of residents. The results of the two phases of were quite similar. The total evaluation scores in 2017 and 2020 were 6.74 and 6.81, respectively, indicating that the quality of the ecological transportation system is relatively stable after the completion of the eco-city construction. In the sub-items, higher scores were found in travel convenience and travel environment, because of their reasonable planning and construction process and residents’ good feel to use. Lower scores were in travelling mode and spatial layout construction, due to the substantial differences between internal development and construction process of the eco-city, and weak points in the construction. We found the problems and put forward the corresponding promotion strategies, which is useful for the future construction of Sino-Singapore Tianjin Eco-city and other urban ecological transport constructions.