*Article* **The Influence of Climate Warming and Humidity on Plant Diversity and Soil Bacteria and Fungi Diversity in Desert Grassland**

**Yi Zhang <sup>1</sup> , Yingzhong Xie 1,2, Hongbin Ma 1,2, Juan Zhang <sup>1</sup> , Le Jing <sup>1</sup> , Yutao Wang <sup>1</sup> and Jianping Li 1,2,\***


**Abstract:** Our study, which was conducted in the desert grassland of Ningxia in China (E 107.285, N 37.763), involved an experiment with five levels of annual precipitation 33% (R33), 66% (R66), 100% (CK), 133% (R133), 166% (R166) and two temperature levels (inside Open-Top Chamber (OTC) and outside OTC). Our objective was to determine how plant, soil bacteria, and fungi diversity respond to climate change. Our study suggested that plant *α*-diversity in CK and TCK were significantly higher than that of other treatments. Increased precipitation promoted root biomass (RB) growth more than aboveground living biomass (ALB). R166 promoted the biomass of Agropyron mongolicum the most. In the fungi communities, temperature and precipitation interaction promoted *α*-diversity. In the fungi communities, the combination of increased temperature and natural precipitation (TCK) promoted *β*-diversity the most, whose distance was determined to be 25,124 according to PCA. In the bacteria communities, *β*-diversity in CK was significantly higher than in other treatments, and the distance was determined to be 3010 according to PCA. Soil bacteria and fungi *α*and *β*-diversity, and ALB promoted plant diversity the most. The interactive effects of temperature and precipitation on C, N, and P contents of plants were larger than their independent effects.

**Keywords:** precipitation changes; increased temperatures; desert grassland; plant diversity; plant biomass; soil bacteria diversity; soil fungi diversity
