摘要
:明晰土壤盐分空间变异性是土壤盐渍化程度研究和盐碱地改良的前提。本研究选取干旱内陆河流域石羊河下游民勤盆地为研究区,通过对0~30 cm土层土壤盐分原位数据统计学特征、空间自相关性、变异性和分布格局的分析,探讨民勤盆地土壤盐分空间异质性变化规律,以期为研究区土壤盐渍化治理提供理论依据。结果显示:(1)实测土壤盐分含量和变化范围均随土层加深而变小,且均呈偏正态分布。(2)Moran’s I 指数均呈“∽”型波动趋势且值域范围随土层加深而变大,正(负)空间自相关性均随距离的增大而减小(0~10 cm负的空间自相关性相反)。(3)变异函数均以指数模型为最好,R2随土层加深而变大(0.62→0.69→0.81),RSS均是0.0002,C0/(C0+C)和A0变化规律一致,随着土层加深空间异质性由弱到强烈再到中等。(4)插值精度10~20 cm > 20~30 cm > 0~10 cm。3个土层土壤盐分均存在空间分异特性,水平方向(同一土层)上,盐渍化程度均自西南向东北逐渐增加;垂直方向(不同土层)上,分布规律由简单到复杂,从聚集状态(0~10 cm)逐渐趋于斑块化(10~20 cm)和斑点化(20~30 cm)。非盐化土(<1.50%)和4 种不同程度盐渍土在3 个土层中均有分布,盐渍土面积中度(>70.00%)>强度(约20.00%)>轻度(约9.00%)>盐土(<0.50%)
Abstract
Clarifying the spatial variability of soil salinity is the aim of soil salinization research and saline-alkaliland improvements. In this study, the Minqin Basin in the lower reaches of the Shiyang River in the arid inlandriver basin was selected as the study area. By analyzing the statistical characteristics, spatial autocorrelation,variability, and distribution patterns of soil salinity in situ data of the 0-30 cm soil layer, the changes in thespatial heterogeneity of soil salinity could be explored to provide a theoretical basis for soil salinity in the studyarea. The measured soil salinity content and its variation range both decreased as the soil layer increased, andboth were in a skewed normal distribution. Morans I index showed atype fluctuation trend, and the rangeof values increased with the soil layer, and the positive (negative) spatial autocorrelation decreased as the distanceincreased (negative spatial autocorrelation of 0- 10 cm was opposite). The exponential model was the mostsuitable for use with the variogram. The R2 increased with soil depth (0.620.690.81), and the RSS was0.0002. Variation rules of C0/(C0+C) and A0 were consistent, and the spatial heterogeneity ranged from weak tostrong to moderate with soil depth. Accuracy of the interpolation was 10-20 cm > 20-30 cm > 0-10 cm. The soilsalinity of the three layers had spatial differentiation characteristics, and the degree of salinization increasedgradually from southwest to northeast in the horizontal direction (the same soil layer). In the vertical direction(different soil layers), the distribution patterns changed from simple to complex, and gradually tended to patches(10-20 cm) and spots (20-30 cm) from the aggregation state (0-10 cm). Nonsalinized soil (70.00%) > strength (approximately 20.00%) > mild (approximately 9.00%) > saline soil (<0.50 %).关键词
土壤盐分/空间变异/地统计学/民勤盆地/石羊河下游Key words
soil salinity/spatial variation/geostatistics/Minqin Basin/downstrearm of Shiyang River引用本文复制引用
刘新,郝媛媛,花立民.石羊河下游民勤盆地土壤盐分空间分异特征[EB/OL].(2024-03-01)[2026-04-02].https://chinaxiv.org/abs/202403.00025.学科分类
农业科学研究/环境科学基础理论
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