Effects of winter wildfire on soil physical and chemical properties of western Sichuan subalpine grassland

To explore the effects of winter wildfire on soil physical and chemical properties of western Sichuan subalpine grassland, subalpine areas with and without fire on west Sichuan were selected as researched regions. Comparing the soil physical and chemical properties of the surface soil at 0-20 cm depth, soil moisture and density of soils in alpine grassland did not change by winter wildfire although soil aeration performance improved. Moreover, winter wildfire significantly increased the content of surface layer soil organic matter, total nitrogen, available potassium and available phosphorus (P0.05), however, winter wildfire did not change the soil soluble nitrogen content significantly. Overall, winter fire behavior can improve soil environment for plant growth by providing greater extended space for root growth and more nutrients for plant growth.