| 摘要: |
| 【 目的】分析高寒草甸退化梯度下土壤理化性质的变化，探究影响高寒草甸退化的关键土壤因子，旨在为西藏退化高寒草甸恢复与重建提供理论支撑。【 方法】以藏北那曲地区的轻度、中度、重度退化高寒草甸为研究对象，测定其土壤理化性质，并采用相关性分析和主成分分析研究了影响高寒草甸退化的关键土壤因子。【 结果】随着高寒草甸退化程度的加剧，土壤有机质、全氮、全磷、全钾、速效氮、速效磷、速效钾含量和含水率、总孔隙度、砂粒含量均下降，土壤体积质量、pH值及土壤砾石、黏粒、粉粒含量升高，土壤粒径分形维数增大，土壤团聚体平均质量直径（MWD）、几何平均直径（GWD）均呈下降趋势。土壤团聚体的破坏率以中度退化高寒草甸最大，其次为轻度退化草甸，重度退化草甸最小。相关性分析结果表明，土壤总孔隙度与速效钾、有机质、速效氮含量呈显著或极显著正相关，砂粒与速效钾、有机质、全氮、速效磷、速效氮含量呈显著或极显著正相关，土壤黏粒含量与pH值呈显著正相关关系，土壤水稳性团聚体几何平均直径与速效氮含量呈显著正相关。主成分分析结果表明，土壤有机质、速效磷、速效氮和速效钾含量和质地是影响高寒草甸退化的关键因子。【 结论】不同退化阶段高寒草甸土壤理化性质有明显差异，中度退化阶段是藏北高寒草甸退化的转折期，此时应进行人为干预以促进退化高寒草甸的恢复。 |
| 关键词: 高寒退化草甸 土壤理化性质 主成分分析 藏北 |
| DOI：10. 13207/j. jnwafu. 2026. 06. 009 |
| 分类号: |
| 基金项目:国家重点研发计划项目“青藏高原典型自然保护地生态系统保护恢复及多功能提升技术与示范”（2023YFF1304300）；西藏农牧学院林学博士点（一期）项目（533325001） |
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| Evolution characteristics of soil physical and chemical properties under the degradation gradient of alpine meadow in Northern Xizang |
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LAI Guozhi, CHEN Yifan, MU Chengwei, PENG Yan, WEI Xuehong
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School of Forestry and Grassland Science，Xizang Agricultural and Animal Husbandry University， Nyingchi，Xizang 860000，China
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| Abstract: |
| 【 Objective】The changes of soil physical and chemical properties under the degradation gradient of alpine meadow were analyzed，and the key soil factors affecting the degradation of alpine meadow were explored，in order to provide theoretical support for the restoration and reconstruction of degraded alpine meadow in Xizang.【Method】The mildly，moderately and severely degraded alpine meadow in Nagqu area of northern Xizang was taken as the research object，and the soil physical and chemical properties were determined. The key soil factors affecting the degradation of alpine meadow were determined by correlation analysis and principal component analysis.【Result】As the alpine meadow degradation intensified，the contents of soil organic matter，total nitrogen，total phosphorus，total potassium，available nitrogen，available phosphorus，available potassium，water，total porosity and sand all decreased，the soil volume mass，pH value，soil gravel，clay and silt content increased，the fractal dimension of soil particle size increased，and the average mass diameter（ MWD） and geometric mean diameter（ GWD） of soil aggregates generally decreased. The highest destruction rate of soil aggregates was found in moderately degraded alpine meadow，followed by the mildly degraded meadow，and the lowest in the severely degraded meadow. The results of correlation analysis showed that the total porosity of soil was sig?
nificantly or extremely significantly positively correlated with the contents of available potassium，organic matter and available nitrogen. Sand content was significantly or extremely significantly positively correlated with the contents of available potassium，organic matter，total nitrogen，available phosphorus and available nitrogen. Soil clay content was significantly positively correlated with pH value，and the geometric mean diameter of soil water-stable aggregates was significantly positively correlated with available nitrogen. The results of principal component analysis showed that the contents of soil organic matter，available phosphorus，available nitrogen and available potassium nutrient and texture were the key factors affecting the degradation of alpine meadow.【Conclusion】The physical and chemical properties of alpine meadow soil in different degradation stages are significantly different.The moderate degradation stage is the turning point of alpine meadow degradation in northern Xizang，and human intervention should be carried out at this stage to promote the restoration of degraded alpine meadow. |
| Key words: degraded alpine meadows physiochemical properties principal components analysis Northern Xizang |
