银川平原土壤盐渍化与土地利用强度的空间关联分析

Spatial Relationship Analysis Between the Soil Salinization and Land Use Intensity in Yinchuan Plain

银川平原盐渍土时空格局及其与土地利用强度变化关联关系的空间区位特征,可从土地利用强度的角度阐释土壤盐渍化的动因,为盐渍化因地制宜的治理提供参考依据。本文重点研究了盐渍土空间分布定量遥感生成方法,通过土地利用遥感制图、半方差函数的地统计学方法和灰色关联度分析法,对2004-2010年银川平原的土地利用强度变化、土壤盐渍化程度变化及各类盐渍土与土地利用强度的关联度,进行了空间区位分布特征的可视化表达。研究结果表明:银川平原的发展仍具集聚效应,土地利用强度变化与城镇体系格局、交通干线、沟渠分布、土壤盐分含量密切相关;2004-2010年间,银川平原土壤盐渍化存在整体减轻、局部加重的空间分布特征,与土地利用强度变化间的响应关系,存在较明显的空间差异;银川平原土壤盐渍化程度变化与土地利用强度变化间的关联度为0.7781,与水体、耕地这2种土地类型间的关联程度最高。银川平原土壤盐渍化的干扰活动中,水体与耕地类型的利用行为是较重要的影响因子。

Accurately get the spatial distribution of soil salinization and the spatial location characteristics of its relationship with land use intensity can explain the reason of soil salinization from a perspective of land use in- tensity, so as to provide a reference to local planning and management. In this paper, taking Yinchuan Plain as the research area, we primarily studied the method of getting the saline soil＇ s spatial distribution based on re- mote sensing images. Combined with the land use remote sensing mapping and with the support of statistical methods based on semivariance function and grey correlation theory, the visual expression of spatial location dis- tribution characteristics are developed for land use intensity change, soil salinization change, and the respond re- lationships between each kind of saline soil and land use intensity in Yinchuan plain. The main conclusions are presented as follows： first, the development of Yinchuan plain had an agglomeration effect. Land use intensity change was closely related to the urban system structure, the distribution of road and channels and soil salinity. Second, the soil salinization change of Yinchuan Plain revealed a spatial distribution of entire alleviation but lo- cal aggregation feature. The response relationship between saline soil and land use intensity change was spatial heterogeneity. Third, the correlation coefficient between the saline soil level change and land use intensity change was 0.7781. The correlation degree between land use and saline soil were found higher in water and culti- vated land, which showed that the land use could influence soil salinization distribution characteristics. There- fore, among all the land use types, water and cultivated land were important factors of influence to soil saliniza- tion. Generally, strengthen the awareness of environmental protection and cultivation will help reduce soil sec- ondary salinization. Further improve the water conservancy facilities can help reduce groundwater salinity. More- over, we can protect cultivated land to promote the sustainable development of agriculture.