Soil organic carbon(SOC)and total nitrogen(TN)play an important role in the global carbon and nitrogen cycles.Soil aggregates are critical reservoir of SOC and TN.Therefore,in areas with severe wind erosion,the change...Soil organic carbon(SOC)and total nitrogen(TN)play an important role in the global carbon and nitrogen cycles.Soil aggregates are critical reservoir of SOC and TN.Therefore,in areas with severe wind erosion,the changes in the accumulation of SOC,TN,clay,silt,and sand contents within different dry aggregate size fractions can offer crucial insights into soil conservation by the control of wind erosion.In this study,surface soil samples(0–5 cm depth)were collected from farmland and grassland in the Bashang region of northern China in 2020.The bulk soil and aggregate size fractions were used to determine the concentrations of SOC,TN,clay,silt,and sand.The results showed that:(1)farmland had lower SOC and higher TN than grassland;(2)SOC in the aggregates of farmland decreased with increasing aggregate size(P<0.010),while SOC in the aggregates of grassland increased with increasing aggregate size(P<0.010),and nonsignificant variation of TN and clay was observed among different aggregate sizes;(3)the mean of aggregate silt significantly decreased with increasing aggregate size and the mean of aggregate sand increased with increasing aggregate size(P<0.001);(4)no correlations between sand or silt of aggregate and TN or texture of bulk soil was found;and(5)SOC in bulk soil was correlated with those in different aggregate sizes,and was also affected by the texture of bulk soil(P<0.010).This study highlights the role of dry soil aggregate size in the redistribution of SOC,TN,clay,silt,and sand contents under different land uses,thereby facilitating the understanding of the process of wind erosion induced SOC,TN,and mineral dust emission.展开更多
基金supported by the National Natural Science Foundation of China(4227100242201002)+2 种基金the Foundation of Central Guidance for Local Scientific and Technological Development(246Z3705G)the Water Conservancy Science and Technology Plan Project of Hebei Province(2023-64)the Hebei Natural Science Foundation(D2021205013).
文摘Soil organic carbon(SOC)and total nitrogen(TN)play an important role in the global carbon and nitrogen cycles.Soil aggregates are critical reservoir of SOC and TN.Therefore,in areas with severe wind erosion,the changes in the accumulation of SOC,TN,clay,silt,and sand contents within different dry aggregate size fractions can offer crucial insights into soil conservation by the control of wind erosion.In this study,surface soil samples(0–5 cm depth)were collected from farmland and grassland in the Bashang region of northern China in 2020.The bulk soil and aggregate size fractions were used to determine the concentrations of SOC,TN,clay,silt,and sand.The results showed that:(1)farmland had lower SOC and higher TN than grassland;(2)SOC in the aggregates of farmland decreased with increasing aggregate size(P<0.010),while SOC in the aggregates of grassland increased with increasing aggregate size(P<0.010),and nonsignificant variation of TN and clay was observed among different aggregate sizes;(3)the mean of aggregate silt significantly decreased with increasing aggregate size and the mean of aggregate sand increased with increasing aggregate size(P<0.001);(4)no correlations between sand or silt of aggregate and TN or texture of bulk soil was found;and(5)SOC in bulk soil was correlated with those in different aggregate sizes,and was also affected by the texture of bulk soil(P<0.010).This study highlights the role of dry soil aggregate size in the redistribution of SOC,TN,clay,silt,and sand contents under different land uses,thereby facilitating the understanding of the process of wind erosion induced SOC,TN,and mineral dust emission.
