生物炭对棉花产量及土壤有机碳含量影响的Meta分析OA

Applying biochar can significantly increase cotton yield and soil organic carbon contents.However,considerable uncertainties remain regarding the effects of biochar application on yield increase-carbon sequestration-emission reduction.We performed a meta-analysis of 315 observations from 45 field studies to quantify the effects of biochar on cotton yield and soil organic carbon contents,across varying environmental conditions.The magnitude of such effects varied with climatic factors,soil conditions and farmland management measures.Our results show that:① Biochar addition led to substantial increases in cotton yield(+14.8％)and the soil organic carbon(+25％).② The comprehensive effects of cotton field yield and soil organic carbon are highest under moderate temperature,precipitation,and sunshine conditions.③ Grey desert soil areas can increase cotton yield by 18.7％and SOC by 21.3％,and the effect is significantly enhanced when the soil pH is alkaline.④ An appropriate biochar application rate,along with a small amount of nitrogen fertilizer and an appropriate amount of irrigation,can achieve the synergy of high yield and carbon sequestration.The synergistic effect of high yield and carbon sequestration can be achieved by applying 5～15 t/hm² biochar and 300～450 mm irrigation combined with a small amount of nitrogen fertilizer.⑤ The cotton yield and SOC were more sensitive to changes in temperature and the soil pH,respectively.These findings provide insights into the effect of biochar addition on biogeochemical cycles,functions,and services in cotton planting areas across diverse spatial and temporal scales.