Understanding the temperature and moisture sensitivity of soil organic matter （SOM） mineralization variations with changes in land cover is critical for assessing soil carbon （C） storage under global change scenar...Understanding the temperature and moisture sensitivity of soil organic matter （SOM） mineralization variations with changes in land cover is critical for assessing soil carbon （C） storage under global change scenarios We determined the differences in the amount of SOM mineralization and the temperature and moisture sensitivity of soils collected from six land-cover types, including an orchard, a cropland, and four forests, in subtropical south- eastern China. The responses of SOM mineralization to temperature （5, 10, 15, 20, and 25~C） and moisture （30%, 60%, and 90% of water-holding capacity [WHC]） were investigated by placing soil samples in incubators. Soil C mineralization rate and cumulative C mineralization were higher in orchard and cropland soils than in other forest soils. With increasing temperature, soil C mineralization rates and cumulative C mineralization increased with the rise of WHCo The temperature sensitivity of soil C mineralization was not affected by land-cover type and incubation moisture. All soil temperature treatments showed a similar response to moisture. Cropland soil was more respon- sive to soil moisture than other soils. Our findings indicate that cropland and orchard soils have a higher ability to emit CO2 than forest soils in subtropical southeastern China.展开更多
基金Natural Sciences Foundation of China(31270519,31470506,31130009,31290221)
文摘Understanding the temperature and moisture sensitivity of soil organic matter （SOM） mineralization variations with changes in land cover is critical for assessing soil carbon （C） storage under global change scenarios We determined the differences in the amount of SOM mineralization and the temperature and moisture sensitivity of soils collected from six land-cover types, including an orchard, a cropland, and four forests, in subtropical south- eastern China. The responses of SOM mineralization to temperature （5, 10, 15, 20, and 25~C） and moisture （30%, 60%, and 90% of water-holding capacity [WHC]） were investigated by placing soil samples in incubators. Soil C mineralization rate and cumulative C mineralization were higher in orchard and cropland soils than in other forest soils. With increasing temperature, soil C mineralization rates and cumulative C mineralization increased with the rise of WHCo The temperature sensitivity of soil C mineralization was not affected by land-cover type and incubation moisture. All soil temperature treatments showed a similar response to moisture. Cropland soil was more respon- sive to soil moisture than other soils. Our findings indicate that cropland and orchard soils have a higher ability to emit CO2 than forest soils in subtropical southeastern China.
