三峡库区植物篱对土壤理化性质及抗蚀性的影响

Effects on Soil Physicochemical Properties and Anti-erosion Caused by Plant Hedgerows in Three Gorges Reservoir Area

三峡库区坡耕地水土流失严重,已经威胁到库区生态环境及库区安全。利用长期定位小区试验,通过对2种植物篱及对照处理的对比分析,研究不同植物篱对坡耕地土壤理化性质及土壤侵蚀的影响。结果表明:黄荆和紫背天葵2种植物篱处理在不同程度上均改良了土壤物理性质,不同位置土壤养分指标表现为带内最高,带间最低,带上和带下介于两者之间。对照处理土壤养分指标均表现为从坡顶向坡脚逐渐富积的特点。不同植物篱带内土壤抗蚀性的强弱分别为:黄荆(79.2%)>紫背天葵(15.3%)>CK(8.7%),除了砂粒、粉粒和粘粒含量外,植物篱带内土壤抗蚀指数与其他土壤理化性质间均具有显著或极显著的相关性。植物篱带内土壤抗蚀指数随着土粒浸水时间的增加而减小,两者呈三次多项式函数关系。2种植物篱处理中黄荆改良土壤理化性质、减轻土壤侵蚀的效果优于紫背天葵。

The soil erosion of sloping farmed in Three Gorges reservoir area is serious,which has been a threat to the ecological environment and the safety of the reservoir.Based on a 5-year fixed field expermient,an comparative analysis between the 2 hedgerows and CK to research the effects on soil physicochemical properties and soil erosion caused by plant hedgerows was carried out.The results showed that： The two plant hedgerows of Vitex negundo and Begonia fimbristipula had improved soil physical properties to varying degrees;In different locations of hedgerow plots,soil nutrient index were with the highest content within the hedgerow,and with the minimum contents in the steep land between hedgerows,and the contents before the hedgerows and behind the hedgerows were between the first two locations,the nutrient index increased gradually from the top of the hill to the foot in the same slope of the control treatment,which showed that these nutrient index moved and enriched to the lower slope;The strength of soil anti-erodibility in different hedgerows separately showed that： Vitex negundo（79.2%）〉 Begonia fimbristipula（15.3%） CK（8.7%）,in addition to sand,silt and clay content,there were significant or very significant correlations between the soil anti-erosion index within the hedgerow and other soil chemicophysical properties.The index of soil anti-erosion within the hedgerows decreased with the increase of time,there were cubic polynomial relationships between them;Considered improving soil physicochemical properties and lightening soil erosion,Vitex negundo hedgerow was better than Begonia fimbristipula hedgerow.