Source data for Afforestation of severely desertified land in semi-arid areas promotes soil carbon and nitrogen accumulation through microbial necromass

Afforestation is an important measure used to expand carbon (C) sequestration and mitigate climate change. However, the impact of soil microbial necromass on soil C and nitrogen (N) sequestration still remain unclear following afforestation of severely desertified land. We investigated 10-, 20-, and 40-year-old Caragana microphylla and Pinus sylvestris var. mongolica plantations (±2 years) established on mobile dunes in northern China, taking mobile dunes and natural grassland and forest as references. We then collected topsoil (0−20 cm) samples. We aimed to reveal the capability of SOC and TN storage, the contribution of microbial necromass to SOC and TN, and factors affect the accumulation of microbial necromass following afforestation by quantifying microbial necromass dynamics based on amino sugar biomarkers and measuring biotic and abiotic factors.