黄土高原丘陵区坡改梯后的土壤质量效应

摘要

采用时空互代法,以黄土丘陵区纸坊沟流域不同年限梯田为研究对象,选取坡耕地为对照,分析了坡耕地改造梯田后,土壤物理、化学和生物学性质的演变过程.结果表明,黄土丘陵区坡耕通过工程措施改造为梯田当年,在土壤扰动和水土流失双重作用下,土壤物理、化学和生物学质量呈现不同程度下降或没有显著变化.随着改造年限的延长,土壤质量显著提高,表现为土壤物理性质和抗蚀性显著增强,化学性质显著提高,土壤微生物属性及活性显著增加.土壤质量指数(SQI)作为土壤理化和生物学性质的综合反映,其随改造年限的增加呈显著的线性增加关系,说明采用工程技术进行坡改梯后,土壤经营和管理趋于科学化,土壤质量向良性方向发展.%Terraces at different years in loess hilly region were chosen as subject to reveal changes in soil phyico-chemical and biological properties after slope cropland was rebuild to terraces.The results showed that slope cropland had a low content of phyico-chemical and biological quality because of serious soil erosion and improper cultivation.Soil phyico-chemical and biological properties had no remarkable change or a little drop in the first year of terracing under the action of soil disturbance and the reduction of erosion.Soil qualities (including of soil physical properties and anti-erodibility, chemical properties, microbial biomass and activity) were improved significantly with the terracing age.Soil quality index (SQI), integral indicator to reflect soil phyico-chemical and biological properties,appeared linear increasing with years by regression analysis.In brief, when slope cropland was rebuilded to terrace, soil was managed scientifically and soil quality was significantly improved.