To explore the effects of biochar on soil and water conservation in slopping farm-land of black soil region,the experiments for the influences of different amounts of biochar supply (0 t/hm2,25 t/hm2,50 t/hm2,75 t/hm2 and 100 t/hm2) on soil structure,water holding property,runoff and sediment control,etc.were conducted in the run-off plots,which were located at the slopping farm-land with three degrees of terrain slope in Hongxing state farm of Beian City,Heilongjiang Province in the typical black soil belt.The results showed that the biochar could effectively improve the soil structure in black soil region,and the soil bulk density was decreased with the increase of amount of biochar,but the soil porosity was just opposite.And some indexes for indicating the soil water holding capacity,such as saturated soil water content,field water capacity and soil water storage were all increased with the increase of biochar supply amount.The run-off and soil erosion in slopping farm-land could also be controlled by suitable supply of biochar,the best treatment for run-off and sediments control was that with 75 t/hm2,and the effect of run-off control was better than that of the sediment control.Biochar supply also could reduce the soil nutrient loss and improve the spacial distribution of soil nutrient at different degrees,and the soil nutrient contents for the four treatments of biochar supply were all higher than that without biochar supply,and the evenness degree of soil nutrients distribution was also improved obviously,which made the differences of soil nutrients between upslope and downslope reduced.The results could provide a new way for efficient,green and recycling utilization of straw resource in the northeast black soil region,the theoretical foundation for prevention and control of water and soil erosion in slopping farm-land of black soil region,which have important significance to promote the regional sustainable development of agriculture.%为了探索生物炭对黑土区坡耕地的水土保持作用效果,于2015年在东北黑土区典型黑土带上的黑龙江省北安市红星农场3°坡耕地上的径流小区内,开展了不同生物炭施用量(0、25、50、75、100 t/hm2)对土壤结构、持水性能、径流泥沙控制等影响的试验研究.结果表明:生物炭可有效改善黑土区土壤结构,随着生物炭添加量的增加,土壤容重随之减小,而土壤孔隙度则会明显提高;土壤饱和含水率、田间持水量和土壤储水能力均随生物炭施用量的增加而增加;适当施加生物炭对黑土区坡耕地降雨径流及水土流失具有较好的控制作用,75 t/hm2处理具有最好的径流泥沙控制效果,其中径流控制效果好于泥沙控制;施加生物炭还可以不同程度地减少黑土区坡耕地土壤养分流失,并可以改善养分的空间分布,4种生物炭用量处理的养分含量不仅在数量上高于对照处理,而且在均匀程度上有较大的改善,减缓了坡度对土壤养分造成的坡上与坡下的差异.研究结果为东北黑土区秸秆资源的高效、绿色、循环利用提供了一条新的途径,可为黑土区坡耕地水土流失防治提供理论依据和技术支撑,对该区农业可持续发展具有重要意义.
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