长江中下游低山丘陵区土地整治对区域水土流失变化的影响机制研究

Study on the Influence Mechanism of Land Consolidation on Regional Soil Erosion Changes in the Hilly Area of the Middle and Lower Reaches of the Yangtze River

长江经济带生态环境保护是当前全社会共同关注的问题,土地整治作为"山、水、林、田、湖、草"生命共同体全面保护的重要手段,目前大部分地区的土地整治主要关注于农田生产条件的改善,对水土流失等关键环境问题的考虑不足。以宁镇扬丘陵区的典型土地整治区金坛区、溧阳市为研究区,通过土地整治水平的定量化评价与水土流失量的精准化估算,重点研究土地整治工程对水土流失的关键影响要素及其机理。研究发现:(1)土地整治显著降低了水土流失强度,整治后项目区水土流失量降幅达到43.1%;(2)土地平整度、投资强度、田块规则度3个指标对区域水土流失防治作用最为显著,对水土流失量减少的贡献率分别达41.5%、28.1%、13.2%;(3)在水土流失严重地区应加大土地整治投资力度、加强土地平整工程、加强田块细碎化与规则化整治。

The ecological environment protection of the Yangtze River Economic Belt is a common concern of the whole society.Land consolidation is an important means to protect the orderly ecological system for mountains,rivers,forest,farmland,lakes and grassland,but at present,in most areas the land consolidation mainly focuses on the improvement of agricultural production conditions,which lacks consideration of key environmental issues such as soil erosion.This study take Jintan and Liyang city as the reach areas which are the typical land consolidation areas in Ning-Zhen-Yang hilly area,based on the quantitative evaluation of land consolidation and the accurate estimation of soil erosion,we have focused on the key factors and mechanisms of land consolidation works on soil erosion.The results of this study:(1)Land consolidation significantly reduced the degree of regional soil erosion,and the amount of soil erosion in the project area dropped to 43.1%after remediation.(2)Land flatness,investment intensity and field rule degree have the most significant effect on regional soil erosion control,and contribution rates to reduce soil erosion amount are 41.5%,28.1%and 13.2%respectively.(3)In areas where soil and water loss is serious,we should increase investment in land consolidation,strengthen land leveling works,and intensify the fragmentation and regularization of plots.