Response of soil properties and C dynamics to land-use change in the west of Loess Plateau

Abstract

Land-use change (LUC) is widely considered a major factor that affects soil organic carbon (SOC) sequestration. The impacts of four LUC types on soil properties, SOC, particulate organic carbon (POC) and labile organic carbon (LOC) at the 0-100 cm depth were examined in the west of Loess Plateau, northwest China. Bulk density at the 20-40 cm depth increased significantly after native grassland conversion to cropland, while artificial grassland establishment and abandonment on former cropland caused reverse change. Soil water content in the profile increased 60-230% after cultivation and decreased 32-49% after abandonment (p < 0.01). The particle size distribution also showed a response to LUC. Only artificial grassland establishment caused an SOC sink of 32% at the 0-10 cm depth as well as two labile fractions. SOC tended to increase after cultivation and after abandonment, with 6% and 20% at soil surface, respectively. There were increasing trends in POC and LOC. After afforestation on former native grassland, SOC tended to decrease (23%) at the 0-10 cm depth while POC and LOC tended to increase (33% and 6%, respectively). Principal component analysis was successful in separating LUC through soil property parameters. Carbon sequestration is largely ascribed to increased below-ground production and tillage elimination after perennial alfalfa (Medicago sativa L.) plantation. Irrigation and fertilization activities contribute to SOC accumulation after cultivation to some extent. The self-restoration dynamic depending on time since abandonment is important to SOC change. A lower proportion of stabilized carbon results in a slow rate of SOC accumulation after afforestation. It is necessary to investigate the long-term dynamic after LUC.

Effect of land use, season, and soil depth on soil microbial biomass carbon of Eastern Himalayas

“…Bulk density (BD) of the present study (0.62-0.83 g cm −3 ) is within the range reported by Baumler and Zech (1994) (0.6-1.8 g cm −3 ), and it increases with a decrease in soil depth in all the land-use types. Our results agree with the report of several other studies from different land-use types of the world (Zhang et al 2014;Francaviglia et al 2017). Higher soil bulk density in the inner soil layers is due to less organic matter and weight of the overlying horizons (Grüneberg et al 2014).…”

Cultivation effects on the carbon and nitrogen dynamics at depth in oasis farmlands of the Southern Tarim Basin, China

“…Thus, the largest SOC sequestration rate for 80-and 100-year farmlands was possibly favored by the continuous increasing clay and silt content in surface soils. These results further demonstrated that fertilization in combination with irrigation activities can lead to surface soil C and N sequestration following the conversion of desert soil to farmland (Zhang et al 2014).…”

Can Conservation Tillage and Residue Management Effects on Sensitivity of Labile Soil Organic Carbon Fractions and Soil Organic Carbon Stocks in Sub-Tropical Ecosystems: A Review

“…Second, following the initial rapid decline, SOC would reach a new steady-state after about 50 years of cultivation, therefore resulting in a slower rate of SOC loss during the later years (Lal, 2004a). Krishna et al, (2018) Lihua Zhang et al, (2014) reported that the significant increases (31.83%) in the SOC concentrations were observed at AG compared with AL at a depth of 0-10 cm, with no significant effect at a depth of 10-100 cm [Fig. 12a].…”