Astragalus variabilis Bunge is a widespread locoweed that threatens livestock production in desert grassland. No research has reported its possible ecological functions due to focus being on its negative effect on livestock production. This study aimed to assess the effects of A. variabilis on soil properties and its possible role in improving soil quality in desert grassland. Soil samples were collected in Astragalus patches and the adjacent bare patches over two successive growing seasons in Alxa desert grassland where A. variabilis was favoured to spread. Soil properties including texture, water content, dry bulk density, porosity, available nutrients, organic matter, and soil microbial biomass were determined at 15 study sites. There was no significant difference in soil texture between Astragalus-dominant and bare patches; but organic matter (OM), available N and P, and microbial biomass in surface soil (0–30 cm) were significantly higher in Astragalus patches. Furthermore, microbial biomass showed a significantly positive correlation with available nutrients and OM. Levels of water soluble salt were significantly lower in A. variabilis surface soils under drought conditions. Results suggested that A. variabilis was associated with some positive changes in soil properties, and was potentially important in improving soil chemical and microbial properties in desert grassland ecosystems. Consequently, total elimination of locoweed should not necessarily be considered the best solution to locoweed poisoning in livestock.

黄芪变种（Astragalus variabilis Bunge）是一种广泛的疯草，威胁着沙漠草原上的牲畜生产。没有研究报道其可能的生态功能，因为关注其对畜牧生产的负面影响。这项研究旨在评估曲霉对土壤特性的影响及其在改善沙漠草原土壤质量中的可能作用。在连续两个生长季节中，在A. variabilis的阿拉善沙漠草原中，从黄芪斑块和相邻的裸露斑块中收集土壤样品被青睐传播。在15个研究地点确定了土壤特性，包括质地，含水量，干容重，孔隙率，有效养分，有机质和土壤微生物量。在以黄芪为主的裸露斑块和裸露斑块之间，土壤质地没有显着差异。但是在黄芪斑块中，表层土壤（0–30 cm）中的有机质（OM），有效氮和磷以及微生物量显着较高。此外，微生物生物量与可利用的养分和OM呈显着正相关。在干旱条件下，曲霉表层土壤中水溶性盐的含量显着降低。结果提示曲霉与土壤特性的一些积极变化有关，对于改善沙漠草原生态系统的土壤化学和微生物特性可能具有重要意义。因此，完全消除根瘤不必认为是解决牲畜根瘤中毒的最佳方法。