有机粪肥施入对农田剖面土壤固碳潜力的影响OA

[Objective]Soil organic carbon(SOC)in cropland is an important component of the terrestrial ecosystem carbon pool.The application of organic manure,as a critical agricultural management practice,has been extensively validated to significantly enhance soil organic carbon(SOC)content and stock.However,Current research mainly focuses on the SOC fixation and mechanisms in the 0-20 cm surface soil layer,with little attention given to the carbon sequestration potential of deeper soil layers.[Method]This study used a meta-analysis method to systematically analyze the impact of animal manure application on SOC distribution and stock in the soil profile of global croplands.[Result]The results showed that the application of animal manure increased SOC stock in different soil layers.In the surface layer(0～20 cm),SOC stock increased from 28.3 t·hm-2 to 36.4 t·hm-2,with an increase of 28.6％.In the 20～40 cm layer,SOC stock increased from 23.6 t·hm-2 to 27.5 t·hm-2,with an increase of 16.5％while in the>40 cm layer,SOC stock increased from 45.6 t·hm-2 to 48.7 t·hm-2(6.8％).The new SOC sequestration efficiency(NCE)was highest in the 0～20 cm layer(14.1％),significantly higher than in the 20～40 cm layer(10.0％)and the>40 cm layer(2.9％).Also,it was observed that soil carbon sequestration efficiency was co-regulated by both natural factors(annual mean temperature,annual mean precipitation)and anthropogenic factors(fertilizer type,nitrogen application rate,land use type,and application duration).Specifically,the impacts of annual mean temperature and annual mean precipitation on sequestration efficiency vary across different soil layers.Moreover,the combined application of animal manure and an appropriate amount of nitrogen fertilizer significantly enhanced SOC stock in the surface soil layer.[Conclusion]This study provides a theoretical basis for developing differentiated carbon sequestration strategies based on soil profile characteristics.Furthermore,the study highlights the significance of optimizing agricultural management to enhance soil carbon stock,mitigate climate change,and achieve sustainable agricultural development.