Table of Content

10 June 2026, Volume 45 Issue 6

Previous Issue   

Effect of biochar addition on the growth and non-structural carbohydrates of Cunninghamia lanceolata and Michelia macclurei seedlings in mixture.

ZHANG Yatong, YU Qingzhou, HE Ziqing, ZHAO Qian

2026, 45(6):  1761-1771.  doi:10.13292/j.1000-4890.202606.021

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Continuous plantation of Cunninghamia lanceolata in monoculture leads to the accumulation of allelochemicals in soils, which inhibits the growth of itself and associated tree species. Exploring the effects of biochar addition on the growth of C. lanceolata and Michelia macclurei seedlings in mixture and on soil physicochemical properties can provide a scientific basis for mitigating the allelopathic effect and for improving the management of mixed C. lanceolata plantations. In this study, a pot experiment was conducted with one-year-old C. lanceolata and M. macclurei seedlings in mixture, under four corn-straw-derived biochar application levels (0%, 2%, 4%, and 6% of dry soil mass). The effects of different biochar addition levels on organ biomass, non-structural carbohydrates (NSC), and soil physicochemical properties were evaluated. The results showed that: (1) Biochar application significantly increased soil pH,   available phosphorus, available potassium, soil water content and soil total porosity, while significantly decreased soil bulk density (P<0.05). (2) The total biomass of M. macclurei seedlings under biochar amendment treatments ranged from 13.4 to 19.8 g·plant^-1, which was significantly lower than that of the control (34.7 g·plant^-1). In contrast, the total biomass of C. lanceolata seedlings increased significantly by 26.2% under the 4% biochar treatment (P<0.05). (3) The soluble sugar (SS) and NSC contents were the highest in leaves, accounting for 48.4% and 45.6% of total NSC in C. lanceolata and M. macclurei seedlings respectively, significantly higher than that in other organs (P<0.05). The starch was mainly stored in roots, accounting for 51.2% and 56.4% of the total for C. lanceolata and M. macclurei, respectively. (4) Biochar application significantly reduced SS content in both species, as well as the SS and NSC contents in the stems of C. lanceolata and in the roots and stems of M. macclurei (P<0.05). In conclusion, 4% biochar treatment promoted the growth of C. lanceolata seedlings. C. lanceolata and M. macclurei seedlings adjusted their NSC allocation strategies in response to the variations of soil physicochemical properties and alleviated allelopathic stress. This study highlights the importance of biochar in improving soil environment and mitigating allelopathy, providing a scientific basis for the rational application of biochar in sustainable management of C. lanceolata mixed-species plantations.





Distribution characteristics and influencing factors of Juglans regia dead trees in the West Tianshan valley of Xinjiang, China.

BA Xuerui, LIU Huaqing, JIA Yanyan, XIE Xinran, ZHANG Wei, YANG Yunfei

2026, 45(6):  1772-1779.  doi:10.13292/j.1000-4890.202606.002

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Tree mortality is an important part of forest community dynamics. It is one of the important mechanisms regulating population structure and dynamics. In this study, a census was conducted on Juglans regia dead trees in the four slope directions of Xinjiang Wild Walnut Nature Reserve. We analyzed the characteristics of the quantitative distribution of four mortality types in J. regia trees, and the effects of diameter at breast height (DBH) and slope direction on the J. regia dead trees. The results showed that the main mortality types of J. regia trees in the reserve were freezing injury mortality (64.87%), disease mortality (31.94%), insect pest mortality (30.54%), and rot mortality (27.35%). Freezing injury mortality, disease mortality, and insect pest mortality occurred simultaneously. The largest proportion of dead J. regia trees in the four slope directions was on semi-shady slope (41.12%), followed by semi-sunny slope (29.34%), then shady slope (18.96%), and the smallest proportion was on sunny slope (10.58%). The proportion of  J. regia dead trees by age group was as follows: middle-aged trees (47.90%), mature trees (34.13%), young trees (9.78%), and old trees (8.18%). The proportion of  J. regia dead trees with the same mortality type differed significantly among the four slope directions and different age classes (P<0.05). Freezing injury mortality and disease mortality mainly occurred in middle-aged trees, while insect pest mortality and rot mortality primarily occurred in mature trees. The numbers of freezing injury mortality and insect pest mortality were significantly correlated with DBH, crown width, and slope direction (P<0.05). The numbers of disease mortality were extremely significantly correlated with DBH (P<0.01). This study can provide scientific reference for the protection of J. regia in Xinjiang Wild Walnut Nature Reserve.





Variations of soil organic carbon stock and its stability along the succession stage in subtropical secondary forests.

PENG Chao, XU Yanyang, QIN Yi, ZHANG Yun, ZHANG Yang, WU Ting, MAO Rong

2026, 45(6):  1780-1788.  doi:10.13292/j.1000-4890.202606.027

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Soil organic carbon (SOC) plays a critical role in sequestering atmospheric carbon dioxide and mitigating global climate change in forests. However, how forest succession affects soil organic carbon fractions and their stability in subtropical forests remains unclear. To address this knowledge gap, we examined the effects of forest succession on soil organic carbon stock and stability and their regulatory factors along the successional gradient of coniferous forest, coniferous and broad-leaved mixed forest, evergreen and deciduous broad-leaved mixed forest, and evergreen broad-leaved forest in Matoushan, Jiangxi Province. Soil samples were collected from the humus layer, 0-10 cm soil layer, and 10-30 cm soil layer. The variations of soil organic carbon, particulate organic carbon (POC), mineral-associated organic carbon (MAOC) contents, and soil physical and chemical properties were analyzed. The results showed that SOC stock increased along forest succession stages. Broad-leaved mixed forests (5065 g C·m^-2) and evergreen broad-leaved forests (5940 g C·m^-2) had significantly greater SOC stock than coniferous forests (2900 g C·m^-2) and coniferous and broad-leaved mixed forests (3132 g C·m^-2). As forest succession proceeded, POC concentration increased across all soil layers, whereas MAOC concentration gradually increased in the humus and 0-10 cm soil layers but initially declined and then increased in the 10-30 cm soil layer. The proportion of POC to SOC generally increased with forest succession, but the proportion of MAOC to SOC declined, resulting in elevated POC∶MAOC ratio. Compared to coniferous forests, the average POC∶MAOC ratio increased by 87%, 245%, and 360% in the coniferous and broad-leaved mixed forests, broad-leaved mixed forests, and evergreen broad-leaved forests, respectively. In the humus layer, soil organic C and POC concentrations were primarily influenced by available phosphorus, while MAOC concentration was influenced by fine root biomass. In the 0-10 cm soil layer, SOC and POC concentrations were mainly affected by soil total nitrogen (N) concentration and C∶N ratio, whereas MAOC concentration was mainly regulated by pH. In the 10-30 cm soil layer, organic C and its fractions were predominantly influenced by total N concentration and C∶N ratio. These findings suggest that community succession enhances SOC accumulation but reduces SOC stability by increasing the proportion of POC fraction in subtropical forests. These change trends are primarily modulated by fine root biomass and soil nutrient (i.e., N and phosphorus) availability during forest succession.





Surface electrochemical properties of soils and the influencing factors under different land use types.

LIU Junyang, ZHOU Zhengchao, SU Xuemeng, LIN Weidong

2026, 45(6):  1789-1799.  doi:10.13292/j.1000-4890.202606.010

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Changes in land use patterns have marked effects on soil surface electrochemical properties, which are directly related to key soil functions such as nutrient absorption, pollutant migration, and soil aggregate stability. We examined surface electrochemical properties of soils and the influencing factors across five typical land use types on the Loess Plateau, including forest, shrubbery, grassland, abandoned land, and farmland. A combination of methods was used to measure soil surface electrochemical properties. The results showed that soil surface charge quantity, surface potential, surface charge density, specific surface area, and surface electric field across in the five land use types ranged from 6.52 to 11.44 cmol c·kg^-1, -157.26 to -104.12 mV, 0.17 to 1.36 C·m^-2, 19.30 to 144.72 m²·g^-1, and 2.35×10⁸ to 19.14×10⁸ V·m^-1, respectively. Soil surface potential, surface charge density, and surface electric field in forests were significantly lower than those in farmland, while soil surface charge quantity and specific surface area in forests were significantly higher than those in abandoned land and farmland (P<0.05). The independent contribution rates of root characteristics and soil physicochemical properties to the variations of soil surface electrochemical properties were 25.2% and 44.8%, respectively, and the relative contribution of their interaction was 26.9%. Among all the root characteristics, root length density was the major factor influencing soil surface electrochemical properties, with a contribution rate of 87.1%. In terms of soil physicochemical properties, clay and organic matter contents were the primary factors influencing soil surface electrochemical properties, with contribution rates of 83.2% and 11.1%, respectively. Soil physical and chemical properties significantly influenced soil surface electrochemical properties, with path coefficients of -0.82 and -0.83, respectively, and the direct effects being dominant. In conclusion, soil surface electrochemical properties on the Loess Plateau differed significantly with land use types, and were regulated jointly by roots and soil physicochemical properties. Our results enhance the understanding of soil surface electrochemical properties on the Loess Plateau and provide theoretical support for soil management and regulation as well as for the assessments of ecological benefits.





Effects of smooth vetch cover and fertilization management on soil health in citrus orchards.

YANG Xin, ZENG Lixiong, LEI Lei, ZHANG Jiajia, YANG Hongbing, XIAO Wenfa

2026, 45(6):  1800-1809.  doi:10.13292/j.1000-4890.202606.018

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Evaluating the effects of smooth vetch cover and fertilization management on soil health is essential for improving the long-term benefits of citrus orchards. We conducted an experiment within a citrus orchard in the Three Gorges Reservoir Area. There were three treatments, no cover with fertilization (NC), smooth vetch cover with fertilization (VC), and smooth vetch cover without fertilization (NF). We analyzed soil physicochemical properties and microbial indicators in three depths (0-10, 10-30, and 30-50 cm). The effects of different treatments on soil health were evaluated with a comprehensive indicator set. The results showed that, compared to the NC treatment, the VC treatment significantly increased soil temperature (by 2.94%, 3.10%, 3.67%), and cation exchange capacity (by 12.06%, 13.06%, 35.83%) across all three soil layers, as well as soil moisture (by 34.84%, 7.33%), Gram-negative bacterial abundance (by 38.41%, 5.95%), and the Gram-negative to Gram-positive bacteria ratio (by 43.20%, 8.36%) in the 0-10 and 10-30 cm soil layers (P<0.05). Compared to the NF treatment, the VC treatment significantly reduced soil bulk density (by 9.0%, 6.9%, 2.0%), soil temperature (by 4.56%, 2.74%, 2.38%), and fungal∶bacterial ratio (by 12.46%, 3.63%, 12.23%) across all three soil layers, while significantly increased cation exchange capacity (by 21.17%, 2.50%, 35.26%), Gram-negative bacterial abundance (by 65.50%, 12.13%), and the Gram-negative∶Gram-positive ratio (by 67.14%, 2.26%) in the 0-10 and 10-30 cm layers (P<0.05). In addition, the soil health index of the VC treatment in the three soil layers (0.605,  0.497, and 0.473) was significantly higher than that of the NC treatment (0.546, 0.481, and 0.401). Its biological health index (0.690, 0.507, and 0.434) was also significantly higher than those of the NC (0.562, 0.495, and 0.379) and NF (0.474, 0.477, and 0.373) treatments. In conclusion, smooth vetch cover combined with fertilization could enhance soil health.





Impacts of long-term straw return on soil carbon stability and fertility in rice-wheat rotation system.

KOU Na, ZHAO Qiong, PENG Binwei, TANG Qiang, SONG Jing, JIANG Hongqiang, WU Wenge

2026, 45(6):  1810-1817.  doi:10.13292/j.1000-4890.202606.038

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To explore the long-term effects of straw returning on soil carbon stability in rice fields, a nine-year field experiment was conducted in a rice-wheat rotation system located in the mid-to-lower reaches of the Yangtze River. There were four treatments, including combined rice and wheat straw returning, wheat straw returning, rice straw returning, and a control (no straw returning of rice or wheat). Soil organic carbon components and physicochemical properties were measured. The results showed that combined rice and wheat straw returning significantly increased soil ammonium nitrogen and available potassium concentrations (P<0.05). Straw returning significantly increased the concentrations of soluble, particulate, and total organic carbon (P<0.05), as well as the proportion of active organic carbon (soluble and particulate) in total organic carbon (combined rice and wheat straw returning > wheat straw returning > rice straw returning > control). All straw returning treatments significantly increased microbial biomass  carbon, with the highest increase (4.71 times) in the combined rice and wheat straw returning treatment. Different straw returning treatments had varying effects on carbon conversion-related enzyme activities. Specifically, combined rice and wheat straw returning had the greatest impact on β-1,4-glucosidase and β-1,4-xylosidase activities. There was a significant relationship between active organic carbon concentration and β-1,4-glucosidase and β-1,4-xylosidase activities. Overall, long-term straw returning, especially the combined rice and wheat straw returning, significantly increased soil microbial biomass, enzyme activity, and organic carbon concentration, but reduced the stability of soil organic carbon.





The effectiveness of different conservation tillage technologies in degraded brown soil of Changtu County, Liaoning Province.

YANG Miaoyin, ZHANG Wei, HU Yanyu, CHEN Xin, HE Hongbo, ZHANG Xudong, XIE Hongtu, ZHANG Yulan, MA Qiang, ZHOU Feng, YUAN Lei, LU Caiyan

2026, 45(6):  1818-1827.  doi:10.13292/j.1000-4890.202606.029

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We investigated the effects of different conservation tillage technologies on the ecological benefits, crop yield and net economic benefit of degraded brown soil, based on the conservation tillage experimental research platform of Lao Cheng Town, Changtu County, Liaoning Province. The treatments included conservation tillage technology with in-situ straw recycling \[conventional ridge tillage without straw return (57 cm uniform ridges), wide double row with one space (57-114 cm) and narrow double row with one space (45-105 cm) no-tillage with straw strip mulching\] and integrated planting-breeding with chicken manure recycling technology \[fertilizer reduction combined with chicken manure under wide double row with one space and no-tillage with straw strip mulching conditions: conventional NPK (control), 75% NPK+3000 kg·hm^-2 chicken manure, 50% NPK+6000 kg·hm^-2 chicken manure, 25% NPK+9000 kg·hm^-2 chicken manure, and 0% NPK+12000 kg·hm^-2 chicken manure\]. Soil physicochemical properties and crop yields were measured. The results showed that, compared to conventional ridge tillage without straw return, double row with one space and no-tillage technologies with straw strip mulching for three years increased soil moisture retention, carbon sequestration and soil fertility (no statistical significance, P>0.05). These technologies significantly increased corn yield and economic benefit by 12.7% and 20.0% (P<0.05), with economic benefit being increased by 3277.9 and 4276.4 yuan·hm^-2·a^-1 for wide and narrow double row with one space no-tillage with straw strip mulching, respectively. Compared with the conventional application amount of NPK, different amounts of NPK reduction combined with chicken manure for three years significantly increased soil ecological benefits (P<0.05). Among the combinations, 50% NPK combined with 6000 kg·hm^-2 chicken manure and 25% NPK combined with 9000 kg·hm^-2 chicken manure had the best effects, with soil carbon sequestration potential, fertility increase potential, comprehensive ecological benefits, and corn yield being enhanced by 9.2%, 8.2%, 6.2%, and 15.2%, respectively. The economic benefits of these two chicken manure substitutions were enhanced by 3759.7 and 3406.3 yuan·hm^-2·a^-1 compared to conventional NPK application amount. In conclusion, conventional NPK fertilization combined with straw in-situ cycling conservation tillage technology and integrated NPK reduction with chicken manure recycling can increase crop yield and net economic benefit by improving soil ecological benefits, indicating that these conservation measures can be demonstrated and promoted in Changtu County.





Effects of organic fertilizer application on biomass and soil physicochemical properties in four cultivated grasslands of Yunnan.

LI Ruogu, TABA Ciren, LI Xueqiang, ZHANG Linjie, WU Jianping

2026, 45(6):  1828-1837.  doi:10.13292/j.1000-4890.202606.017

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Artificial grasslands are crucial for the sustainable and high-quality development of animal husbandry in China. The application of organic fertilizer in artificial grasslands is an indispensable management to achieve high yield and sustainable soil fertility. We examined the application of organic fertilizer (18000 kg·hm^-2) on artificial grasslands with each of four species, Trifolium repens, Cichorium intybus, Dactylis glomerata, and Plantago asiatica. We assessed the changes in biomass of the four artificial grasslands and soil physicochemical properties including soil organic carbon, moisture content, pH, total nitrogen, total phosphorus, and available phosphorus. The results showed that organic fertilizer application increased aboveground biomass by 11.0%-38.8% in the four artificial grasslands. Meanwhile, organic fertilizer application improved soil organic carbon content and soil water content. Specifically, soil organic carbon contents of Dactylis glomerata, Trifolium repens, Cichorium intybus, and Plantago asiatica were significantly increased by 40.3%, 25.7%, 17.5%, and 11.1%, respectively. Soil water contents were significantly increased by 11.1%, 8.4%, 8.1%, and 3.7%, respectively. However, other physicochemical factors such as ammonium, nitrate, total phosphorus, and available phosphorus content exhibited greater variability across grasslands with different plant species. Furthermore, correlation analysis and structural equation modeling revealed that the primary growth drivers differed among the four artificial grasslands. Trifolium repens and Dactylis glomerata were mainly influenced by total phosphorus and soil organic carbon contents, while Cichorium intybus and Plantago asiatica were primarily affected by soil organic carbon and water contents. In conclusion, organic fertilizer application enhanced grassland biomass by affecting soil nutrients, but the underlying mechanisms differed across grass species. These findings provide a scientific basis for the sustainable utilization and high-quality establishment of artificial grasslands in southern China.





Effects of planting pattern and slope on soil erosion and maize yield in dryland of the Loess Plateau.

ZHOU Xujiao, ZHAO Gang, ZHANG Jianjun, WANG Shuying, DANG Yi, WANG Lei, ZHOU Gang, LI Shangzhong, FAN Tinglu, HU Jingyu, MI Wenbo

2026, 45(6):  1838-1849.  doi:10.13292/j.1000-4890.202606.001

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This study aimed to address the challenges associated with water resources scarcity and soil erosion hazards. We conducted a field experiment following split-plot design, with planting pattern (flat planting with half film mulching and double ridge-furrow planting with full film mulching) as main plots and slope gradient (5°, 10°, 15°, 20°, and 25°) as split-plots. The impacts of different planting patterns on runoff characteristics, sediment loss, soil nutrient loss, and corn  yield of sloping farmland were examined. Results showed that runoff volume, runoff coefficient, and sediment loss in the treatment of flat planting with half film mulching first increased and then decreased as slope gradient increased. Runoff volume, runoff coefficient, and sediment loss in the treatment of double ridge-furrow planting with full film mulching increased as slope gradient increased. The maize  yield in both planting patterns first increased and then decreased as slope gradient increased. Compared to flat planting with half film mulching, double ridge-furrow planting with full film mulching significantly reduced organic matter loss (51.9%), total nitrogen loss (59.8%), total phosphorus loss (42.6%) and total potassium loss (27.5%), while significantly increased runoff volume (8.6%-127.6%), runoff coefficient (8.6%-127.6%), rainfall thresholds for runoff generation (5.8%), and sediment loss (23.5%). Double ridge-furrow planting with full film mulching increased runoff and sediment loss and reduced nutrient loss in runoff and sediment, and thereby increased maize  yield (20.9%-42.1%). This planting pattern has good water and soil conservation and yield-increasing benefits, and is suitable for application in slope ranges of 11° to 13°. The results revealed the influence mechanism of double ridge-furrow planting with full film mulching on the soil erosion process in slope farmland and provided a scientific basis for soil erosion control and efficient water resources utilization in dryland farming of the Loess Plateau.





Effects of short-term asparagus straw incorporation on soil fungal communities and Chinese cabbage yield.

SHENG Yuzhen, LAI Jia, WEI Shugu, YE Pengsheng, LIU Yong, ZHANG Qianfang, LIU Jia, HUANG Ling

2026, 45(6):  1850-1860.  doi:10.13292/j.1000-4890.202606.014

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The characteristic of soil fungal communities are important indicators for assessing soil quality. In this study, we investigated the correlation between different short-term straw incorporation methods and soil physicochemical properties, fungal communities and Chinese cabbage yield. There were four different treatments in the experiment, including all fresh chopped straw incorporation (FSA), half fresh chopped straw incorporation (FSH), all rotted chopped straw incorporation (RSA) and half rotted chopped straw incorporation (RSH), with conventional tillage without straw incorporation as the control (CK). The results showed that asparagus straw incorporation reduced the yield of Chinese cabbage, among which FSA and FSH significantly decreased yield by 7.11% and 6.02% (P<0.05), respectively. There were no significant effects of straw incorporation on soil physicochemical properties. Shortterm incorporation of asparagus straw increased fungal community diversity, with the FSA treatment showing significantly higher fungal community diversity than CK (P<0.05). At the genus level, straw incorporation treatments increased the relative abundance of Aspergillus, but decreased that of Pseudopyrenochaeta and Plectosphaerella. Redundancy analysis showed that pH and available potassium were the key environmental factors affecting fungal community composition (P<0.05). Co-occurrence network analysis revealed an increase in fungal symbiotic network complexity and connection tightness. In summary, short-term asparagus straw incorporation altered the diversity and composition of fungal communities by changing the proportion of beneficial fungi and pathogenic fungi. This poses a certain biocontamination risk to soil quality and ultimately leads to a reduction in cabbage yield. Therefore, full consideration should be given to the micro-ecological effects of straw incorporation in practical production to avoid potential adverse impacts caused by indiscriminate straw return practices.





Effects of biodegradable mulching film on soil water and heat conditions and water use efficiency of sugar beet.

LI Yinghao, LI Xin, REN Huimin, HUANG Chunyan, XUE Chunlei, LI Zhi, HAN Kang, JIAN Caiyuan, TIAN Lu, GUO Xiaoxia

2026, 45(6):  1861-1869.  doi:10.13292/j.1000-4890.202606.008

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In response to challenges such as low rainfall, low water use efficiency, and pollution from traditional plastic mulch in Inner Mongolia, a field experiment was conducted in 2023 at the Inner Mongolia Autonomous Region Academy of Agriculture and Animal Husbandry Sciences. There were four treatments: black polyethylene mulch (PE), white biodegradable water-permeable mulch (S1), gray biodegradable water-permeable mulch (S2), and no mulch (CK). We investigated the degradation performance of different types of mulch and their effects on soil moisture, temperature, and water use efficiency of sugar beets. The results showed that the white biodegradable mulch had the fastest degradation rate. Compared to the no-mulch treatment, all three types of mulch improved soil hydrothermal environment, with the best performance of the white biodegradable mulch. Under white biodegradable mulch coverage, soil moisture significantly increased by 6.95% to 18.86%, and soil temperature significantly rose by 2.5 to 5.5 ℃. Water consumption, water consumption intensity, and water consumption modulus coefficient significantly decreased by 10.15%, 28.67%, and 12.94%, respectively. Water use efficiency significantly improved by 14.89%, while soil bulk density significantly decreased by 3.05%, and soil porosity significantly increased by 6.14%. Net photosynthetic rate, intercellular CO₂ concentration, transpiration rate, and stomatal conductance of sugar beets significantly increased by 18.27% to 30.42%, 13.55% to 21.29%, 22.28% to 59.85%, and 17.94% to 76.26%, respectively. In conclusion, white biodegradable mulch coverage effectively regulates soil hydrothermal environment, improves water use efficiency during the growth period, and promotes sugar beet growth.





Effects of drought stress and rehydration on leaf photosynthetic characteristics, quality and yield of soybean.

HE Peijin, SUN Anni, LI Lin, XU Qingzhe, HUI Mengmeng, GAO Xining, WANG Liwei, YIN Hong

2026, 45(6):  1870-1879.  doi:10.13292/j.1000-4890.202606.003

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Drought events have occurred more frequently under climate change, which greatly threaten agricultural development. With the cultivar “Liaodou 15”, we examined the drought resistance and the post-disaster recovery process of soybeans. There were three drought stress intensities (mild, moderate, and severe), with water being controlled at the beginning of the three-leaf stage and flowering stage of soybeans. After the stress was over, water was restored to the control level (with soil relative humidity maintained at 80% ± 5%). The changes in photosynthetic characteristics, quality and yield of soybeans under drought stress and re-watering conditions were investigated. The results showed that drought stress reduced net photosynthetic rate, fat content, pod number, pod weight, number of seeds, and the yield of soybeans, but increased water use efficiency, protein content, number of shriveled pods, and number of shriveled seeds. The more severe the drought stress, the greater the impacts were. After re-watering for 10 to 15 days, soybean plants under mild and moderate drought  nearly recovered to the control level, whereas those under severe drought  were irrecoverable and became non-stomatal. Compared to the seedling stage, soybeans showed a more significant response to drought stress during the flowering and podding stages. By investigating dynamic stress resistance indicators such as photosynthetic elasticity, resistance, and resilience, establishing a more comprehensive drought resistance evaluation system, this study provides important theoretical basis for drought-resistant soybean breeding and water management.





Response of potato leaf chlorophyll fluorescence, material accumulation and transport to phosphorus addition in Ningnan mountain area.

WANG Hua, SU Ming, WU Jiarui, HONG Ziqiang, LI Fanguo, LI Tong, CAI Qiaohong, WU Hongliang, KANG Jianhong

2026, 45(6):  1880-1889.  doi:10.13292/j.1000-4890.202606.009

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Based on the strategic needs of sustainable agricultural development and focusing on the efficient use of fertilizers, we investigated the effects of optimal application of phosphorus fertilizer on photosynthetic efficiency, population structure, and dynamic dry matter accumulation pattern of potatoes. The experiment was carried out in 2018-2019 in Haiyuan County, Ningxia, with ‘Qingyan Potato No. 9’ as the test material, using a randomized block group design. We analyzed leaf fluorescence characteristics, population growth, dynamic accumulation of dry matter, and yield of potatoes under five phosphorus application levels of 0 kg·hm^-2 (P0), 60 kg·hm^-2 (P1), 120 kg·hm^-2 (P2), 180 kg·hm^-2 (P3), and 240 kg·hm^-2 (P4). The results showed that at 60 days after seedling emergence, compared with P0, the 2-year average increases of F_v/F_m (PSII maximum photochemical efficiency), F_v/F_o (PS potential maximum photosynthetic capacity), PI (photosynthetic institutional performance parameter), and ABS/RC (PSⅡ light energy capture efficiency) in leaves under the P1, P2, P3, and P4 treatments ranged from 0.6% to 2.0%, 3.4% to 10.06%, 3.5% to 14.3%, and 8.4% to 18.8%, respectively. The P2 treatment significantly increased potato leaf area index (LAI), photosynthetic potential (LAD), population growth rate (GCR),  net assimilation rate (NAR), and biomass at the point of achieving peak accumulation rate (W_max), along with the highest dry matter accumulation rate (V_max). Compared with P0, the two-year average increases in LAI, LAD, CGR, NAR, W_max, and V_max across P1, P2, P3, and P4 treatments were 1.9%-35.7%, 2.0%-40.7%, 9.5%-29.5%, 13.1%-29.4%, 3.3%-56.8%, and 16.4%-72.2%, respectively. Meanwhile, the 2-year average increase in potato yield of P1, P2, P3, and P4 treatments ranged from 6.1% to 32.9% compared with P0. Among the five phosphorus application levels, potato yield reached the maximum in the P2 treatment. The quadratic function was fitted to yield and phosphorus application level to obtain the optimal economic phosphorus application level of 124 kg·hm^-2 in 2018 and 118 kg·hm^-2 in 2019. W_max and V_max were significantly positively correlated with F_v/F_m, F_v/F_o, PI, ABS/RC, LAI, and LAD, while potato yield was significantly positively correlated with F_v/F_m, F_v/F_o, PI, ABS/RC, LAI, and LAD. The principal component analysis indicated that the composite score of each treatment in the two years was in order of P2>P1>P3>P4>P0. Therefore, phosphorus application level of 120 kg·hm^-2 was the appropriate amount for green and efficient production of potatoes in the semi-arid region of Northwest China.



Physiological and immunological differences in captive forest musk deer (Moschus berezovskii) under different altitudes.

WANG Yichen, ZHANG Zexiu, ZHANG Haonan, LAN Xianna, XU Liancheng, LUO Zhengwei, LI Yixin, LIU Zijun, BAI Jin, HUANG Zhixi, HU Defu

2026, 45(6):  1890-1899.  doi:10.13292/j.1000-4890.202606.006

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This study aimed to investigate the ecological characteristics of captive forest musk deer (Moschus berezovskii) feces using non-invasive methods, and to assess their adaptation to high-altitude environments, with 55 forest musk deer reared in a high-altitude region of Bianba, Tibet and 34 forest musk deer from a low-altitude region in Weinan, Shaanxi. Using enzyme linked immunosorbent assays, we quantified the concentrations of cortisol, triiodothyronine (T3), testosterone, progesterone, and secretory immunoglobulin A (sIgA) in feces. Data were analyzed by independent-samples t tests and hierarchical cluster analysis. Results showed that forest musk deer at high altitude had significantly higher fecal cortisol and T3 levels compared to those at low altitude (P<0.01), while testosterone levels were significantly lower (P<0.01). There were no significant differences in fecal progesterone and sIgA levels (P>0.05). Cluster analysis revealed distinct differences in the distribution proportion of individuals with high, medium, and low physiological index values between the two altitudes. Successful captive breeding of forest musk deer in high-altitude regions requires the selection of individuals with low stress responses, high metabolic activity, and strong intestinal immunity to ensure population health and support the sustainable development of the musk deer industry in plateau environments.





Transcriptomics-based analysis of the effects of longterm fasting on energy metabolism in female Japanese quail (Coturnix japonica).

ZHENG Yi, ZHANG Chenchen, CHEN Jiaqi, CHEN Shanshan, LIN Yi, XIANG Han, LIU Jinwen, LIU Jinsong, LI Ming

2026, 45(6):  1900-1911.  doi:10.13292/j.1000-4890.202606.005

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When food intake is insufficient, the energy expenditure in animals is typically reduced to prolong survival. However, the molecular mechanisms regulating such response are not fully understood. To address this gap, we evaluated the basal metabolic indicators and conducted transcriptomic analyses to investigate the effects of prolonged fasting on energy metabolism in female Japanese quails. There were a control group (no fasting) and three fasted groups, namely fasting group Ⅰ, fasting group Ⅱ, and fasting group Ⅲ, which were fasted for 1, 4, and 6-11 days, respectively. The results showed that fasting significantly reduced body mass of the birds. The rate of daily body mass loss exhibited a U-shaped pattern-Symbol~Binitially rapid, then slowing, followed by an increase. Both the basal metabolic rate (BMR) at the whole-animal level and the mass-specific BMR were significantly lower in fasting group Ⅱ compared with the control group. Fasting significantly reduced serum glucose levels, did not affect serum triglyceride levels, and significantly increased serum uric acid levels. KEGG enrichment analysis provided insights into the pathways involved in the response to insufficient food intake. The analysis revealed significant upregulation of 13 pathways in fasting group I compared with the control group. These 13 pathways were primarily involved in the catabolism of the three macronutrients: carbohydrate (7 pathways), lipid (2 pathways), and protein (3 pathways). Similarly, in fasting group Ⅱ, eight pathways were upregulated, five of which were related to protein/amino acid metabolism, including one protein degradation pathway and three glucogenic amino acid metabolism pathways. As for fasting group Ⅲ, 13 pathways were significantly upregulated, including the ‘autophagy-animal’ pathway. These findings suggest that prolonged fasting induces a marked reduction in energy metabolism in female Japanese quails. Fasting alters the metabolism of all three major nutrient classes. Carbohydrate and lipid catabolism were significantly enhanced, while protein metabolism shows increased catabolic and anabolic activity during Phases I and Ⅱ, with catabolism predominating in Phase Ⅲ. In addition, compared with the control, Phase Ⅰ, and Phase Ⅱ, the ‘autophagy-animal’ pathway was significantly upregulated in Phase Ⅲ, suggesting that birds under sustained energy stress enhanced autophagy to recycle protein-derived substrates and compensated for the reduced nutrient intake. In conclusion, this study provides molecular-level evidence that long-term fasting downregulates energy metabolism in birds and highlights the critical role of autophagy in maintaining energy balance and physiological homeostasis.





Prediction of potential distribution areas of Illicium difengpi in climate change scenarios based on the Biomod2 ensemble model.

ZHANG Xiujiao, WANG Manlian, TANG Hui, LI Yongqing, WANG Ying, LIU Baoyu, WU Chao

2026, 45(6):  1912-1919.  doi:10.13292/j.1000-4890.202606.013

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Predicting the spatial variation of suitable habitat of endangered plants under climate change in the future can provide theoretical guidance for protection and sustainable utilization of populations. Illicium difengpi, an endemic species in karst regions, is a China national secondary protected plant with considerable medicinal, ecological and ornamental value. With 30 geographical distribution points of I. difengpi and 10 environmental variables, we analyzed the potential distribution areas and dominant variables of I. difengpi under the current climate scenario using the Biomod2 ensemble model. The potential distribution area in the future (2050s, 2070s, and 2090s) under three climate scenarios (SSP126, SSP245, and SSP585) was simulated. The results showed that: (1) The ensemble model constructed with three optimal single models (Generalized Additive Models, Maximum Entropy Model, and Random Forest) showed better performance than single models in predicting the suitable areas of I. difengpi, with the true skill statistics (TSS) and the area under receiver operating characteristic curve (AUC) values of 0.890±0.024 and 0.982±0.007, respectively, indicating high prediction accuracy. (2) The mean diurnal range, temperature annual range, precipitation of warmest quarter, and elevation were the dominant variables affecting the distribution of I. difengpi. (3) Under the current climate scenario, the potential suitable area of I. difengpi was approximately 3.28×10⁴ km², concentrated in central, northwest and southwest of Guangxi. (4) Under future climate scenarios, the suitable distribution area of I. difengpi would initially expand and then contract, with the distribution centroid shifting towards the southeast. The results provide a reference for in situ conservation, ex situ conservation, introduction, and domestication of I. difengpi under the background of climate change.





Predicting potential suitable habitats and conservation strategies for Cycas panzhihuaensis under future climate change scenarios.

FENG Yuan, DAI Guanghui, QIN Yangping

2026, 45(6):  1920-1932.  doi:10.13292/j.1000-4890.202606.015

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Climate exerts a significant impact on the geographical distribution of species. Investigating the potential distribution of Cycas panzhihuaensis under the context of climate change is beneficial for conservation. Based on the current distribution points of C. panzhihuaensis, we used the Maximum Entropy (MaxEnt) model to examine the influence of environmental variables on its geographical distribution. The spatiotemporal changes and centroid shift trends in the potential distributions of C. panzhihuaensis were predicted under various climate scenarios (SSP245, SSP585) for both the current and future periods (2050s, 2070s, 2090s). The results showed that: (1) The MaxEnt model performed well in predicting the distributions of C. panzhihuaensis (with an AUC of 0.980), indicating its suitability for further predictive applications. (2) The temperature seasonality, precipitation in the driest quarter, maximum temperature of the warmest month, and organic carbon stock were the main factors influencing the distribution of C. panzhihuaensis. (3) The total suitable habitat for the current distribution of C. panzhihuaensis was 316.58×10⁴ hm², with a highly suitable habitat of 33.87×10⁴ hm². Its distribution appeared relatively continuous, forming a branch-like pattern along the dry, hot river valley regions of the Jinsha River’s great bend and its tributaries. (4) Under future climate change scenarios, the suitable habitat for C. panzhihuaensis will expand. Under the SSP245 and SSP585 scenarios, the maximum total suitable habitat will reach 481.98×10⁴ and 589.16×10⁴ hm², respectively, representing increases of 52.25% and 86.10%. The centroid of the suitable habitat will shift northward by 124.53 and 111.80 km, respectively. The minimum values of highly suitable habitat reduced by 45.87% and 88.34%, respectively. The results indicate that while the overall suitable habitat increases, a significant decrease in the highly suitable habitat can pose serious challenges to the viability of C. panzhihuaensis. Our results can provide a scientific basis for the in situ conservation of C. panzhihuaensis, and provide a reference for the selection of sites for ex situ conservation, introduction, and cultivation.





Biomass allocation pattern and its regulatory factors of grasslands in northern China.

WU Liucui, HU Zhongmin, ZHANG Weirong, CHENG Siyuan, YANG Meihua, WANG Mengdie, WANG Shuxin, QIAN Long, JIN Chuan

2026, 45(6):  1933-1942.  doi:10.13292/j.1000-4890.202606.028

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The allocation patterns of grassland biomass and their regulatory factors in northern China remain poorly understood. We compiled a dataset from literature, integrating 951 independent records on vegetation variables (including aboveground biomass, belowground biomass, root-to-shoot ratio, and species composition), anthropogenic factors (grazing and nitrogen addition), as well as climatic and soil variables. We systematically analyzed the dataset with statistical analysis and machine learning (XGBoost) approaches. The results showed that mean aboveground biomass in northern China grasslands was 191.35±6.97 g·m^-2, belowground biomass was 1461.55±39.11 g·m^-2, and the root-to-shoot ratio was 18.09±0.62. The root-to-shoot ratio exhibited a unimodal pattern with increasing longitude and latitude. Light grazing enhanced biomass, whereas moderate and heavy grazing reduced it. Nitrogen application significantly increased aboveground biomass but decreased belowground biomass. Species composition played a critical role in driving biomass allocation. Grasslands dominated by Poaceae species had higher aboveground biomass but lower belowground biomass and root-to-shoot ratio, whereas those dominated by Asteraceae and Fabaceae species showed higher root-to-shoot ratios. Environmental factors nonlinearly regulated biomass allocation. For instance, belowground biomass first decreased and then increased with increasing mean annual precipitation, while the root-to-shoot ratio initially declined and then rose with increasing mean annual temperature. Our results provide a scientific basis for the sustainable management of grasslands, highlighting the importance of grazing management and nitrogen fertilizer application strategies.





Spontaneous plant composition and species diversity around urban water bodies under the influence of multiple disturbances.

CAI Mengqian, LAN Songtao, JIANG Man, ZHU Chunyang

2026, 45(6):  1943-1955.  doi:10.13292/j.1000-4890.202606.022

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Urban water bodies play a significant supportive role in the composition and diversity of spontaneous plants in the surrounding areas, with such influence being greatly affected by urbanization and human interferences. To explore the performance of water-green composite spaces in supporting spontaneous plant diversity under different types, intensities, and interactions of disturbances, we examined the effects of multiple disturbances on the composition and diversity of spontaneous plants in the green areas around East Lake of Wuhan using redundancy analysis and geographic detector analysis methods. The results showed that: (1) The green space around East Lake of Wuhan was rich in spontaneous plant species, with a total of 129 species belonging to 95 genera and 39 families. The majority of plant species were annual and biennial herbs, and the invasive plant species accounted for a relatively large proportion. (2) Distance from the road, intensity of human activity, and distance from the lake significantly affected spontaneous plant diversity. Distance from the road and intensity of human activity had a negative effect on spontaneous plants of all life forms except annual and biennial herbs. Distance from the lake negatively affected spontaneous plants. (3) Considering the interaction among multiple factors, woody spontaneous plants were more susceptible to the influence of natural conditions such as hydrological conditions. The interaction between the intensity of green space management and the distance from the road had the strongest explanatory power for spontaneous plant diversity. The diversity of spontaneous plants was the highest at medium distance from the road, which to some extent supports the moderate disturbance hypothesis. The results will provide a theoretical and practical reference for the construction of urban water-green composite space with near-natural and low-maintenance spontaneous plant community.





Greenhouse gas fluxes from typical vegetation and water body in Xixi wetland and their influencing factors.

HUANG Yichen, YOU Yuke, YAO Kekan, WANG Yixiang, BAI Shangbin, WANG Nan, ZHOU Xiumei

2026, 45(6):  1956-1965.  doi:10.13292/j.1000-4890.202606.004

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Wetland, as an important carbon pool, plays an important role in global carbon cycling. Variations in greenhouse gas fluxes from wetlands are of significant importance for understanding wetland carbon budget and assessing their climate change mitigation potential. In this study, taking Xixi wetland as the object, four land types (arbor land, arbor-shrub grassland, shrub grassland, and reed grassland) and three aquatic types (water course, pond, and shoal) were selected for in-situ monitoring of greenhouse gas fluxes via static chamber combined with gas chromatography for one year from June 2023 to May 2024. The results showed that greenhouse gas fluxes exhibited significant spatiotemporal variations. Among the four land types, the monthly average CO₂ fluxes were the highest in reed grasslands (557.71 mg·m^-2·h^-1), which was significantly higher than other types (P<0.05). The overall emission fluxes from aquatic types were lower than those from land types. N₂O flux showed a dual source-sink pattern. Reed grasslands acted as a strong emission source (54.34 μg·m^-2·h^-1), while arbor-shrub grassland and certain water bodies served as sinks. The CH₄ emission showed extreme variability, with aquatic types being significantly higher than that of land types (P<0.05), and the highest flux was observed in shoals, reaching 7720.23 μg·m^-2·h^-1. The greenhouse gas fluxes in land systems were positively correlated with environmental factors such as soil temperature and moisture content (P<0.05), while the aquatic systems exhibited a multi-factor nonlinear response pattern. This study systematically analyzed the microhabitat differentiation patterns of wetland greenhouse gas emissions, and revealed the key environmental driving mechanism, providing a scientific basis for accurately assessing the carbon sink function of subtropical urban wetlands.





Effects of nitrogen and phosphorus inputs on the growth of submerged macrophytes and epiphytic cyanobacteria in lakes.

JIA Xiaoyue, XUE Liyang, XIA Shuang, PEI Guofeng

2026, 45(6):  1966-1973.  doi:10.13292/j.1000-4890.202606.011

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We investigated the effects of external nitrogen and phosphorus inputs on submerged macrophytes and epiphytic cyanobacteria in eutrophic lakes, with Vallisneria denseserrulata and Leptolyngbya sp. as model species. We measured changes in water physicochemical parameters, growth responses of the two species, and total phosphorus in water and sediments under low (4.00 mg·L^-1), medium (8.00 and 12.00 mg·L^-1), and high (16.00 mg·L^-1) nitrogen loads, as well as low (0.05 mg·L^-1), medium (0.15 and 1.50 mg·L^-1), and high (7.00 mg·L^-1) phosphorus loads. The results showed that V. denseserrulata adapted to nitrogen and phosphorus variations by adjusting growth strategy. Under low nitrogen load, plant height increased by 3.47%, while the number of ramets increased significantly by 16.44%, 34.25%, and 82.19% under medium and high nitrogen loading, respectively. Plant height was negatively correlated with total ramet number under high nitrogen load (r=-0.285, P<0.05). However, plant height was suppressed under high phosphorus loading. Chlorophyll a content of V. denseserrulata under phosphorus loading was significantly higher than that under nitrogen loading (P<0.05). The biomass of Leptolyngbya sp. did not vary under different nitrogen loading levels. Under low and medium phosphorus loads, the periphytic biofilm biomass of Leptolyngbya sp. was significantly higher than that of the control during the first 30 days (P<0.05). Under high phosphorus load, Leptolyngbya sp. was transformed from periphytic biofilm to planktonic hormogonia within the first 20 days of the experiment, resulting in algal bloom formation. These results suggest that phosphorus loading may be a key environmental factor driving shifts in growth dominance between V. denseserrulata and epiphytic cyanobacteria.





Distribution characteristics of phosphorus species and their coupling with iron and sulfur in intertidal sediments of the Liaohe River Estuary.

WANG Xiqian, HAN Xiaokun, LANG Yunchao, LIU Zhanhang, JIE Jingcheng, DING Hu, ZHANG Zhuqing, LIU Congqiang

2026, 45(6):  1974-1982.  doi:10.13292/j.1000-4890.202606.033

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To clarify the biogeochemical coupling mechanism of iron-sulfur-phosphorus in the intertidal zone of estuaries, this study selected the typical intertidal zone of the Liaohe River Estuary as the research area. The phosphorus species and their distribution characteristics, as well as the coupling processes of iron-sulfur-phosphorus were investigated by measuring the content of phosphorus, iron and sulfur species and key environmental variables in the sediment profiles at different tidal levels. The distribution characteristics of total phosphorus (TP, 516.48±133.30 mg·kg^-1), organic phosphorus (OP, 162.58±56.91 mg·kg^-1), and calcium-bound phosphorus (HCl-P, 187.04±95.58 mg·kg^-1) in the sediments showed that the form of inorganic phosphorus was dominant in the sediments and that calcium-bound phosphorus was an important form of inorganic phosphorus. The distribution of phosphorus in the sediments was significantly affected by the frequency of water inundation and human activities. The vertical variations in contents of iron-bound phosphorus and organic phosphorus were minor in the natural sediment profiles, while their contents changed significantly in the sediment profiles disturbed by human activities. In addition, the iron-bound phosphorus (NaOH-P) was significantly positively correlated with the trivalent iron ions (r=0.64) in the sediment profiles of the middle and low tide flats, indicating the controlling role of iron oxides as the carrier of phosphorus in the intertidal zone sediments. Concurrently, the dissimilatory iron reduction process disrupted the mineral structure by converting Fe(Ⅲ) to Fe(Ⅱ) and released bound phosphorus, which was particularly significant under the dynamic redox conditions induced by periodic water inundation in the intertidal zones. There was significant positive correlation between sulfate and OP content in the surface sediments, indicating the indirect regulation of sulfur cycling on phosphorus bioavailability. In the micro-reducing environment formed by the rising tide, the enhanced activity of sulfate-reducing bacteria facilitated the release of soluble phosphorus through sulfide-mediated iron oxide desorption and organic matter mineralization. As the largest coastal wetland in northern China, the Liaohe River Estuary has significantly higher total phosphorus content in sediments than other bays in the Bohai Sea, with a high risk of eutrophication. These results offer critical theoretical foundations for understanding phosphorus cycling mechanisms and advancing eutrophication risk control strategies in coastal wetlands.





Response of chemoautotrophic carbon fixation and iron-bound organic carbon to the changes in salinity and nitrogen concentrations in estuarine sediments.

WU Boshuang, DU Guangyue, SONG Zhenyang, QI Mengting, PAN Yifan, LI Xiaofei

2026, 45(6):  1983-1992.  doi:10.13292/j.1000-4890.202606.031

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Chemoautotrophic carbon fixation (CCF) and iron-bound organic carbon (Fe-OC) in estuarine wetlands are important processes of carbon sequestration and carbon sink enhancement. We investigated changes in CCF rates and Fe-OC concentrations and their correlations with carbon fractions in Chongming Dongtan wetland in Yangtze Estuary, with the responses of CCF and Fe-OC to changes in salinity and nitrogen concentration being assessed in an incubation experiment of salinity gradient (2‰, 5‰, 10‰, and 15‰) and nitrate concentrations (20, 50, and 100 μmol NO₃^-·L^-1). The results showed that CCF rates decreased with increasing salinity by 6.72 ng C·g^-1·d^-1. Fe-OC concentrations decreased with increasing salinity, with the proportion (Fe-OC) of Fe-OC in the total organic carbon concentration being decreased from 30% to 22%. CCF rates and Fe-OC concentrations increased with increasing nitrate concentrations, with CCF rate of 19.3 ng C·g^-1·d^-1 and Fe-OC concentration of 3.77 mg·g^-1, respectively. CCF was significantly positively correlated with Fe-OC, indicating that chemoautotrophic process can favor Fe-OC formation. The enhanced salinity and nitrogen concentrations facilitated organic carbon decomposition, further decreasing the concentrations and stability of organic carbon. Our results suggested that changes in salinity and nitrogen concentrations in estuarine wetlands have great effects on carbon sequestration and carbon sink enhancement process and organic matter composition, further altering the stability of organic carbon.



Impact of water-sediment regulation on cadmium flux to the sea and ecological risk in the Yellow River.

ZHANG Sixuan, SANG Changpeng, LI Enrui, WANG Shaofeng, ZENG Xiangfeng

2026, 45(6):  1993-2001.  doi:10.13292/j.1000-4890.202606.035

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The Yellow River, as an important river flowing into the Bohai Sea, is the main source of trace metal elements in the Bohai Sea. The transformation behavior of cadmium (Cd) directly affects the ecological security of the basin and the environmental quality of the Bohai Sea. Since the implementation of the water and sediment regulation project in 2002, the regulation effect of the project on sediment flux has been well studied, but there is a lack of systematic research on the flux, speciation distribution and ecological risk of Cd. We conducted systematic samplings at seven sites along the main stream of the Yellow River in 2023 and then analyzed the migration and transformation characteristics of Cd and their driving mechanisms during the water and sediment regulation period. The results showed that Cd was mainly transported in the particulate form. The particulate flux at the Huayuankou site was 23463 kg·a^-1, and the dissolved flux was 2591 kg·a^-1. At the Lijin site, the particulate flux was 17776 kg·a^-1, and the dissolved flux was 1169 kg·a^-1. The Cd flux during the sediment regulation period was significantly higher than that in other periods, mainly regulated by water flow velocity, suspended sediment concentration and the intensity of bottom sediment disturbance. The concentrations of available Cd in suspended particulate matter and sediments were relatively high, indicating a high potential ecological risk. The pollution index E_ri value indicated that particulate matter had a high risk of environmental pollution. The resuspension of Cd during the sediment regulation period led to an increase in short-term risk, while the accumulation of Cd in sediments during the dry season might cause long-term ecological threats. Further attention should be paid to its bioavailability after entering the sea. By revealing the significant impact of the water and sediment regulation project on the environmental behavior of Cd, this study provides a scientific basis for improving water environmental quality and ensuring ecological security in the Yellow River Basin.





Impact of land use change on ecosystem wind prevention and sand fixation in Minqin County over the past 40 years.

CUI Jingxuan, JIN Lei, LIU Chunxi, LI Xiufen, SONG Lining, TIAN Yichen

2026, 45(6):  2002-2012.  doi:10.13292/j.1000-4890.202606.025

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Based on land use data from five periods between 1980 and 2020 in Minqin County, we estimated the wind prevention and sand fixation (WPSF) substance amount by using the Revised Wind Erosion Equation (RWEQ) model, and analyzed the impact of land use changes on WPSF functions with the support of GIS. The results showed that: (1) Over the past 40 years, the land use pattern of Minqin County had undergone significant changes. Urbanization had accelerated gradually, the area of deserts and bare land had decreased, and desertification had been brought under control. The area of farmland first increased and then decreased. The area of grassland had gradually recovered after experiencing degradation, and the area of forest had expanded steadily. An ecological barrier dominated by farmland, forest and grassland had formed. (2) The WPSF function of Minqin County consisted of the quantity of WPSF materials and the retention rate of WPSF. Temporally, the total quantity of WPSF materials first increased and then decreased, while the retention rate of WPSF kept rising, with a significant increase after 2000. Spatially, the quantity of WPSF materials showed a distribution pattern of “higher in the north than in the south, and higher in the east than in the west”. The retention rate of WPSF presented a distribution pattern of being higher inside the oasis than outside the oasis. (3) There were significant differences in WPSF function across different land use types. Grassland, as the dominant vegetation type, played a major role, while farmland and forest exhibited higher retention rates. Although deserts and bare land contributed large amounts of WPSF substance, their retention rates remained low. Land use transitions from desert and bare land to grassland and shrubland significantly enhanced WPSF functions, whereas degradation from grassland to desert or bare land and from shrubland to desert induced functional decline. Therefore, particular attention should be paid on grassland desertification and the degradation of forest plantation. The overall improvement of sand fixation in Minqin County depended not only on forest expansion but also on the integrated management of multiple ecosystems such as grasslands. Ecological restoration should follow the principle of “growing grass where it is suitable for grass, leaving land fallow where it is suitable for fallow, and planting trees where it is suitable for forests”.





Effects of microplastics and nanoplastics on the structure and function of microbial community in freshwater biofilms.

XIA Caihui, ZENG Jin, ZHANG Xuejiao

2026, 45(6):  2013-2022.  doi:10.13292/j.1000-4890.202606.007

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Microplastics (MPs) and nanoplastics (NPs) entering freshwater environments interact with freshwater biofilms, potentially impacting ecosystem processes. There are few reports on the effects of MPs and NPs on the microbial community of freshwater biofilms. In this study, water from Lake Taihu was collected. Based on the microcosm experiment and metagenome technology, polystyrene plastics with different concentrations (1 mg·L^-1, 10 mg·L^-1) and particle sizes (1 μm: MPs; 100 nm: NPs) were exposed to freshwater biofilms cultured in the laboratory to explore its effects on the structure and function of biofilms microbial community. The results showed that the dominant phyla of microbial community in freshwater biofilm were mainly Proteobacteria, Bacteroidota, Actinobacteria, Planctomycetota, and Verrucomicrobiota. Both MPs_1 and NPs_1 decreased the relative abundance of Proteobacteria, and the effect of MPs_1 was more significant. Both MPs_10 and NPs_10 decreased the relative abundance of Planctomycetota and Verrucomicrobiota. Both MPs and NPs significantly decreased the relative abundance of degrading functional bacteria such as Rhodoferax and Acidovorax, but promoted the abundance of tolerant bacteria such as Pseudomonas. NPs_1 increased the relative abundance of Bacteroidota and Actinobacteria, reflecting the differential effect of concentration and particle size. Both MPs and NPs increased community richness and decreased Shannon and Simpson diversity. Such impacts depended on both concentration and particle size, with larger particle sizes and higher concentrations leading to more significant changes. Moreover, they altered the biofilm microbial community structure, and the effect of MPs was stronger than that of NPs, reflecting the particle size effect. Function analysis revealed that MPs and NPs reduced the relative abundance of functional genes for amino acid and carbohydrate metabolism, which may interfere with microbial-mediated carbon and nitrogen cycling processes in freshwater ecosystems, thereby affecting ecological functions.





Chinese medicine extracts inhibit hydrogen sulfide-producing activities of oilfield microorganisms.

YANG Chunlu, YANG Yuxiang, LIU Huijie, LI Yingying, LYU Yaqing, ZHAO Jinlong, HAN Siqin, ZHANG Ying, SHI Rongjiu, XIA Yingjie

2026, 45(6):  2023-2031.  doi:10.13292/j.1000-4890.202606.034

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The microbial growth and metabolism in oilfields has been demonstrated to result in the production of hydrogen sulfide (H₂S), inducing a range of production and environmental challenges, including souring and corrosion. However, available biocides pose risks to environmental safety and resistance development. To explore eco-friendly antibacterial strategies, the inhibitory effects of ethanol extracts from six Chinese medicinal plants (Artemisia argyi, Berberis julianae, Lactuca sativa, Linum usitatissimum, Artemisia capillaris, and Xanthium strumarium) were evaluated against multiple H₂S-producing bacterial species isolated from oilfield settings. Furthermore, the combined effects of B. julianae and A. argyi extract with nitrite were investigated. Results showed that A. argyi extract and B. julianae extract, at an initial concentration of 5 mg·mL^-1, completely suppressed the H₂S- production activity of Thermoanaerobacter mathranii strain S1, Tepidimicrobium ferriphilum strain F1, and Moorella glycerini strain A24 within a 15-day period. In contrast, other extracts showed no effects on all the strains. The combination of B. julianae extract or A. argyi extract with nitrite produced a synergistic inhibitory effect on strains S1, A24, and F1. These combinations resulted in a more than 70% reduction in the required extract doses when compared with the use of individual agents. The utilization of A. argyi and B. julianae extract, either individually or in conjunction with nitrite, possesses the potential for environmentally sustainable microbial souring control in oilfield operations.





Differential impact of nitrogen deposition on the stratified effects of forest soil respiration.

FANG Huanying, WANG Jinping, XIAO Shengsheng, SHEN Fangfang, LIAO Yunhua, HUANG Junjie

2026, 45(6):  2032-2042. 

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The depth differentiation in soil carbon dynamics is one of the key factors contributing to the uncertainties in the responses of soil respiration to nitrogen deposition. Analyzing the impact of nitrogen inputs on the vertical differentiation of soil respiration will enhance our understanding of the adaptation mechanisms of soil carbon cycling under global change. We first reviewed the mechanisms underlying soil respiration and changes in atmospheric nitrogen deposition. Then, we examined the effects of both increased and decreased nitrogen deposition on soil respiration at different depths, with a focus on the contribution of nitrogen deposition to soil CO₂ flux in deep soil layer (>30 cm). Microbial nitrogen availability played a key role in regulating deep soil respiration, and nitrogen pool size may drive the response of soil respiration after reduced nitrogen deposition, but the interaction between environmental factors increases its uncertainty. Future research should prioritize exploring the vertical stratification mechanisms of soil respiration and its dynamic thresholds under the situation of reduced nitrogen input, as well as disclosing the interactive effects of multiple factors on carbon-nitrogen-water coupling processes. By integrating source partitioning of respiration components across soil layers and advancing multi-technique approaches, model capability for representing deep carbon turnover can be improved, thereby supporting the accurate assessment of ecosystem carbon budget in the context of global change.





Advances in the application of artificial intelligence for wildlife conservation.

YIN Zhaohua, WANG Qiang, SUN Zhenzhen, LI Boda, ZHAO Xiaotao, ZHOU Xuehong

2026, 45(6):  2043-2054.  doi:10.13292/j.1000-4890.202606.024

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Global biodiversity is in crisis due to climate change and increased human activities. Artificial intelligence (AI), as an emerging technology, has shown great potential in wildlife conservation. We review the progress of the application of AI in wildlife conservation, including the latest application progress in basic research of wildlife conservation, human-wildlife conflict mitigation and risk prevention, combating wildlife crime, and wildlife conservation outreach and public awareness. AI technology has powerful data processing, pattern (image, voiceprint) recognition and modeling prediction capabilities. The application of AI has significantly improved the efficiency and accuracy of wildlife conservation work. However, the application of AI in wildlife conservation still faces some challenges, including low data quality, high equipment cost, poor model adaptability across ecosystems, and ethical disputes.





Application of vetiver system in landscape shaping and rural beautification.

LI Beibei, HU Wenyou, FAN Yanan, ZHANG Yikun, DAI Congjuan, XU Hairun, HUANG Biao, XU Liyu

2026, 45(6):  2055-2062. 

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With the advancement of urban-rural integrated development and ecological civilization construction in China, there is an urgent demand to systemically enhance the ecological services and aesthetic values of rural landscapes. As a perennial grass with vigorous root systems, strong adaptability, and high stress tolerance, vetiver has been widely used in rural landscape shaping. It enhances the artistic expression of natural elements and landscape units, and thus improves the visual quality of mountains, water bodies, forests, farmlands, roads, ponds, and canals. Moreover, vetiver provides multiple ecological functions, including rice pest control, soil and water conservation, slope stabilization, and ecological restoration. We comprehensively introduced the multifunctional advantages of vetiver system in landscape shaping, environmental protection, and economic development, with particular emphasis on its synergistic effects in promoting rural beautification. We evaluated the ecological and economic values of vetiver system in landscape design and rural development. We further analyzed the key points of the vetiver system in rural landscape design. The application of the vetiver system in landscape shaping and rural beautification can achieve the synergistic optimization between ecosystem services and landscape aesthetics, providing a new technical model for rural revitalization that promotes rural economic development and realizes harmonious coexistence between humans and nature.





Advances in the production of high value-added products from brown algae fermentation.

BIAN Mengyang, LI Yaqi, JIN Can, YAO Shuhua, SHI Zhongliang, ZENG Xiangfeng, LI Weiming

2026, 45(6):  2063-2070.  doi:10.13292/j.1000-4890.202606.030

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Fossil energy shortages and escalating environmental issues have spurred interest in marine biomass as a renewable and economically viable resource for bioenergy and green chemical production. Brown algae, characterized by their unique chemical composition of alginate, mannitol, and fucoidan, have emerged as critical feedstocks for high value-added applications. Physical, chemical, biological, and combined pretreatment methods can further enhance the decomposition efficiency. We systematically summarize advancements in brown algal fermentation for high value-added product production. Brown algae can efficiently synthesize biofuels (hydrogen, ethanol, and butanol) through dark fermentation, combined with strain screening and genetic engineering. Additionally, optimizing microbial selection, fermentation conditions (pH, temperature, substrate concentration), and incorporating additives such as nanoscale zero-valent iron (nZVI) can enhance the activities of key enzymes (hydrogenase and alcohol dehydrogenase), thereby improving product yield and energy conversion efficiency. We further identify the key factors restricting the industrial application of brown algae fermentation and propose future research directions.



Building bird habitat networks in high-density urban areas from the perspective of umbrella species protection: A case study of Beijing.

WEI Zhen, ZHANG Mengyuan, FAN Shuxin, DONG Li

2026, 45(6):  2071-2084.  doi:10.13292/j.1000-4890.202606.020

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In the context of rapid urbanization, how to quantitatively select target species and construct multi-group bird habitat networks has become an urgent issue in high-density urban planning, design, and management. We quantitatively selected umbrella species as target species by calculating the umbrella index in Beijing, constructed four types of bird habitat networks: wetland, forest, shrubland, and grassland/farmland, and then conducted the structural evaluation analysis. A total of 53 bird species were identified as umbrella species, belonging to 9 orders and 23 families, covering a number of dominant families of birds in Beijing. Among them, 49 species were protected birds and migratory birds. Moreover, 115, 319, 50, and 490 source sites were identified for wetland birds, forest birds, shrubland birds, and grassland/farmland birds, respectively. The species distribution was dependent on urban bluegreen spaces, with parklands as important habitats for birds in densely builtup urban areas. The biodiversity benefits of urban greening projects, such as the Urban Park Ring and the Plains Afforestation Program, became increasingly evident. The habitat distribution and habitat network structure differed among bird groups. The habitat network of grassland/farmland birds was the most stable, while that of shrubland birds was the most vulnerable. Our results provide important scientific basis and reference for the optimization of urban ecological space based on the enhancement of bird diversity, which is of great significance for the protection of wild birds in Beijing.





Tradeoffs and synergies of ecosystem services and the driving factors in Horqin Sandy Land.

MU Quanfei, WANG Yongfang, GUO Enliang, HONG Ying, MA Haowen, ZHOU Delong, WANG Yanli

2026, 45(6):  2085-2095.  doi:10.13292/j.1000-4890.202606.039

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The environment of Horqin Sandy Land has gradually improved with the implementation of ecological engineering such as the ThreeNorth Shelter Forest Program and the Conversion of Cropland to Forest Program. Exploring the trade-offs and synergies among ecosystem services and their driving factors in Horqin Sandy Land is of great significance for ecological environment protection and governance. We quantitatively assessed four ecosystem services in Horqin Sandy Land in 2022 using the InVEST model, including water yield, soil retention, carbon sequestration, and habitat quality. We analyzed the spatial distribution and driving factors of the trade-offs and synergies among the four services based on Bayesian network and bivariate spatial autocorrelation methods. The results showed that (1) The spatial distribution of soil retention, carbon sequestration, and habitat quality was relatively similar, showing a distribution pattern of high in west and low in east, while water yield showed a pattern of high in east and low in west; (2) Rainfall, rainfall erosion, land use, evapotranspiration, slope, NDVI, NPP, and nighttime light were important influencing factors for the four ecosystem services; (3) At the regional scale, water conservation showed a tradeoff relationship with soil conservation, carbon sequestration services, and habitat quality. There were synergistic relationships among soil conservation, carbon sequestration, and habitat quality. At the county scale, the synergistic relationships between soil conservation and carbon sequestration, as well as between soil conservation and habitat quality, showed spatial heterogeneity and scale effects; (4) The Bayesian network scenario simulation indicated that land use and slope were the driving factors of the trade-off and synergy relationships among the four ecosystem services. Our results can provide a reference for the efficient utilization of ecosystem services in Horqin Sandy Land.





Cultural ecosystem service values and driving factors of urban parks in Xi’an, China.

XUE Mengyang, BAI Huina, LI Linyu, HUANG Xiaojun

2026, 45(6):  2096-2112.  doi:10.13292/j.1000-4890.202606.012

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As an important component of urban ecosystems, park green spaces have received increasing attention for cultural ecosystem services. We evaluated the cultural service values of park green spaces in four typical parks in Xi’an based on the SolVES model, and examined the spatial differentiation of various types of cultural ecosystem services and their influencing factors. The results showed that: (1) Cultural ecosystem service hotspots in typical urban parks exhibited significant spatial heterogeneity, with high-value areas forming a multi-centered clustering pattern. These areas were predominantly distributed around water bodies and the surrounding zones, while certain plazas, greenways, and sports facilities formed localized clusters. (2) Respondents showed different preferences for the cultural ecosystem service values of typical parks. The cultural ecosystem service values showed substantial spatial heterogeneity. Recreational and tourism and aesthetic values were consistently high, with the maximum value index (M-VI) reaching 9-10 in most parks. The cultural heritage, social relations, and spiritual and religious cultural ecosystem service values varied among parks. (3) The influences of different environmental variables on the main cultural ecosystem service values of typical park green spaces differed significantly. Distance to water bodies was the most critical environmental factor, contributing more than 30% and in some cases over 40%, to multiple value types, followed by mountain shadow and slope, while distance to roads, elevation, and land-use cover had limited effects. This study systematically identified key influencing factors of cultural ecosystem services in typical parks in Xi’an, established a multidimensional value assessment framework, provided a scientific basis for constructing a value assessment model for cultural ecosystem services, and further enhanced the contribution of urban green spaces to residents’ health and well-being.