The variations of soil structure and soil physical–chemical properties in the process of alpine grassland desertification were revealed, and the indicators of grassland desertification were put forward in order to deepen the understanding of the law of degradation succession and development of alpine grassland. It was used to provide scientific basis for ecological restoration and improvement of ecological service function of alpine grassland. With severe desertification alpine grassland as the core in the Hongyuan County, Tibetan Qiang Autonomous Prefecture of Ngawa, Sichuan Province, China, along both the directions of wetland and arid grassland, the heterogeneity of soil structure and soil fertility in both directions was studied by the analysis of the mean weight diameter (MWD), geometric mean diameter (GMD), >0.25 mm aggregate content (R_0.25), fractal dimension (D), soil bulk density, soil moisture content, and soil nutrients. Our results showed that MWD, GMD, and R_0.25 all gradually increased, but the D decreased with the reduction in the degree of desertification in the arid grassland and wetland, resulting in the strong stability of soil structure. The decreasing rate of the D in the direction of arid grassland was faster than that of wetland. Therefore, soil structure stability and erosion resistance in the direction of arid grassland were stronger than that of wetland soil; the D had different response to aggregates with different particle sizes. The aggregate less than 0.25 mm (r = 0.981, P < 0.01) and 1–2 mm (r = −0.79, P < 0.01) had the largest responses in the direction of the arid grassland and wetland, respectively; the aggregate more than 1 mm and 1–2 mm can be used as indicators to evaluate desertification of the soil in the direction of the arid grassland and wetland, respectively. The higher the content of the indicating aggregates, the weaker the degree of the desertification.

中文翻译：

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川西北高寒草地荒漠化过程中土壤结构与肥力的异质性

揭示了高寒草地荒漠化过程中土壤结构和土壤理化性质的变化，提出了草地荒漠化指标，以加深对高寒草地退化演替和发展规律的认识。它为高寒草原的生态恢复和改善生态服务功能提供了科学依据。以四川省恩川藏族severe族自治州宏远县以荒漠化严重的高寒草原为核心，沿湿地和干旱草原两个方向研究了土壤结构和土壤肥力的两个方面平均重量直径（MWD），几何平均直径（GMD）大于0.25 mm骨料含量的分析（R _0.25），分形维数（D），土壤容重，土壤含水量和土壤养分。结果表明，干旱草地和湿地的MWD，GMD和R _0.25均逐渐升高，但D随沙漠化程度的降低而降低，从而使土壤结构具有较强的稳定性。D在干旱草地方向上的下降速度要快于湿地。因此，干旱草地方向的土壤结构稳定性和抗侵蚀性强于湿地土壤；的d必须与不同的颗粒尺寸的聚集体不同的响应。骨料小于0.25 mm（r = 0.981，P  <0.01）和1-2 mm（r  = -0.79，P  <0.01）分别在干旱草地和湿地方向上响应最大；大于1毫米和1-2毫米的骨料可分别用作评估干旱草原和湿地方向上土壤荒漠化的指标。指示性骨料的含量越高，荒漠化程度越弱。