Effects of vegetation type and slope position on soil nitrogen transformation rate in Karst regions Net nitrogen mineralization in soils under four forest communities in Hunan Province Study on the nitrogen and phosphorus mineralization of livestock and poultry manure in red soil Relationships between net primary production and nitrogen cycling in Chinese forest ecosystems Impacts of different land use types on soil nitrogen mineralization in Danjiangkou Reservoir Area, China Biological factors influencing nitrogen transformation in wheat fields of lime concreted black soils and their response to different nitrogen supplications The Effects of Different Grass Species on Soil Nitrogen Mineralization in Apple Orchard The Effects of Different Grass Species on Soil Nitrogen Mineralization in Apple Orchard Changes of soil carbon and nitrogen and characteristics of nitrogen mineralization under long-term manure fertilization practices in black soil