Carbon balance and controlling factors in a summer maize agroecosystem in the Guanzhong Plain, China.

Background: Quantifying the carbon balance of agroecosystems and clarifying the factors controlling it are essential for estimating the regional carbon cycle and global carbon balance.

Results: Based on the eddy covariance (EC) technique and soil respiration observations during the 2017 and 2019 summer maize growing seasons, this study analyzed the carbon balance and revealed the factors controlling carbon fluxes in the summer maize agroecosystem. Green leaf area index was the most important factor affecting net ecosystem exchange (NEE), total primary productivity, and total ecosystem respiration (TER) in the rapid development stage during the growing season, followed by soil water content.

Spatial and temporal effects of drought on Chinese vegetation under different coverage levels.

Land surface vegetation dynamics are strongly affected by drought. Thus, understanding the responses of vegetation to drought can inform measures to increase biome stability. In this study, the normalized difference vegetation index (NDVI) and the Palmer drought severity index (PDSI) were utilized to investigate the relationship between vegetation activity and drought across different drought regions and ecological community types from 1982 to 2015.