基于耕地资源质量分类的辽宁省耕地土壤条件及空间分布特征分析

Cultivated Soil Conditions and Spatial Distribution Characteristics Based on Cultivated Land Quality Classification in Liaoning Province

耕地土壤条件是耕地质量高低的重要体现,研究辽宁省耕地土壤条件及其空间分布,可以明晰辽宁省耕地土壤质量情况,为该区域耕地质量的保护与提升以及耕地资源的合理利用提供科学依据。本文基于第三次全国国土调查辽宁省数据,借助ArcGIS和数理统计软件,从耕地质量分类自然地理格局和行政区划的角度,对辽宁省土层厚度、土壤质地、土壤有机质含量和土壤pH值数据进行处理、分析和空间表达。研究结果表明:辽宁省耕地总面积为531.10×10^(4) hm^(2),耕地土层厚度以小于60 cm为主,所占比例达到46.58%;土壤质地以壤质土为主,占比达到82.39%;有机质含量在10~20 g kg^(-1)之间的耕地较多,占比达到70.12%;耕地土壤pH值以弱酸性为主,在5.5~6.5之间的面积最大,占比达到36.67%。辽宁省土层厚度大体呈现"东、西部薄中部厚"的空间分布特征;以壤质土壤为主,大体呈现"东、西和北壤为主,南砂中黏占少许"的空间分布特征;土壤肥力属于中等水平,整体呈现"东北高西南低"的空间分布特征;耕层土壤pH值以弱酸性为主,大体呈现"东酸西碱中适宜"的空间分布特征。

The cultivated land soil condition is an important embodiment of the cultivated land quality.Studying the cultivated land soil condition and its spatial distribution in Liaoning Province can clarify the cultivated land soil quality in Liaoning Province,and provide a scientific basis for the protection and improvement of the cultivated land quality and the rational utilization of cultivated land resources in this region.Based on the Third National Land Survey in Liaoning Province,the data of the soil thickness,soil texture,soil organic matter content and soil pH value were collected and analyzed from the perspective of cultivated land quality classification physical geographical pattern and administrative division by using the methods of ArcGIS and mathematical statistics.The results showed that the total area of cultivated land in Liaoning Province was 5.311 million hm;,and the thickness of cultivated soil layer was less than 60 cm,accounting for 46.58% of total cultivated land area,which was generally presented a spatial distribution characteristic of"thin in the east and west,thick in the middle".Soil texture was dominated by loam soil with an area proportion of 82.39%,showing a spatial distribution characteristic of"loam soil mainly in the east,west and north,clay and sandy soil less in the central and south respectively".Soil organic matter content was mainly between 10 and 20 g kg^(-1),accounting for 70.12% of total cultivated land area.Soil pH value was mainly weak acid,where distributed most between 5.5 and 6.5,accounting for 36.67% of total cultivated land area,which showed a spatial distribution characteristic of"acid in east,alkali in west and moderate in the central".Generally,soil fertility was at a medium level,showing a spatial distribution of"high in the northeast,low in the southwest".