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以江苏中部如东滩涂围垦区为研究区,利用典范对应分析探讨不同空间尺度景观格局对土壤盐渍化程度的影响和贡献度。结果表明:(1)研究区斑块密度、边缘密度、景观形状指数、聚集度指数、散布与并列指数较高,说明景观破碎化程度较高,景观结构复杂,景观分布受人为干扰的程度较大。(2)土壤中Na+和Cl-分别占阳离子总量和阴离子总量的87.4%和90.1%,土壤盐渍化指标的变异系数为53.49%~129.03%,反映了土壤盐分的非均匀分布。(3)研究区景观格局指数在100 m和200 m缓冲区尺度分别能累积解释土壤盐渍化程度变化的66.6%和80.1%,土壤盐渍化程度与农建地和水浇地面积比例呈正相关关系,与旱地面积比例呈负相关关系。(4)景观水平上的土壤盐渍化程度与最大斑块指数、蔓延度指数呈正相关关系,与斑块密度、边缘密度、景观形状指数、香农多样性指数呈负相关关系;斑块类型水平上,最大斑块面积指数、边缘密度、景观形状指数是影响研究区土壤盐渍化程度的共性指标。研究对于优化滩涂围垦区土地利用格局,降低土壤盐渍化程度具有重要意义。
Taking the reclamation area of Rudong beach in central Jiangsu as the research area, the paper analyzes the influence and contribution of landscape pattern with different spatial scales to the degree of soil salinization by the model correspondence analysis. The results show that: (1) The patch density, marginal density, landscape shape index, clustering index, distribution and parallel index are higher in the study area, which indicates that the degree of landscape fragmentation is higher, the landscape structure is complex and the landscape distribution is disturbed by man Big. (2) The contents of Na + and Cl- in soil account for 87.4% and 90.1% of the total amount of cation and anion, respectively. The coefficient of variation of soil salinization index is 53.49% ~ 129.03%, which reflects the non-uniform distribution of soil salinity. (3) The landscape pattern index of the study area can accumulatively explain 66.6% and 80.1% of the changes in the degree of soil salinization in the 100 m and 200 m buffer zones, respectively. The degree of soil salinization is positively correlated with the proportion of agricultural land and irrigated land The correlation was negatively related to the proportion of dry land area. (4) There is a positive correlation between the degree of soil salinization on the landscape level and the maximum patch index and the degree of spreading index, and there is a negative correlation between the degree of soil salinization and the patch density, marginal density, landscape shape index and Shannon’s diversity index. The maximum index of plaque area, edge density and landscape shape index are the common indexes that affect the degree of soil salinization in the study area. Research is of great significance for optimizing the land use pattern and reducing the degree of soil salinization in the reclamation area.