【摘要】 本文采取野外大田试验,运用地统计学和经典统计学方法,研究了不同种植年限压砂地的土壤水分空间变异规律。结果表明,压砂地的土壤含水量均值明显大于裸地(CK)的土壤含水量,且新砂地>中砂地>老砂地>裸地。压砂地各土层的变异系数均小于10%,为弱变异。裸地(CK)第Ⅰ层,老砂地Ⅱ、Ⅲ层土壤水分半方差函数最佳理论模型为指数模型,裸地Ⅱ、Ⅲ、Ⅳ层,新砂地第Ⅱ层,中砂地第Ⅰ、Ⅲ、Ⅳ层,老砂地第Ⅰ层为球形模型,其他各地型、各土层均为高斯模型。新砂地具有强烈的空间自相关性,中砂地具有中等的空间自相关性,而裸地和老砂地空间自相关性微弱,变异主要由随机性变异所引起。基于Surfer8.0绘制新砂地各层土壤含水量等值线分布图,结果显示,第Ⅲ层的等值线最密,第Ⅰ层、第Ⅳ层次之,第Ⅱ层最稀疏,这与Cv和C0/(C0+C)得出的结论一致。以期为压砂地生态农业的生产提供理论依据。更多还原

【Abstract】 Geostatistical and classical statistics were used to characterize spatial variability of soil water content(SWC) in gravel-mulched fields with different planting years. Results indicated that SWC with sand covered was higher than that with bare land(CK), and the SWC ranked as New Gravel-Mulched > Middle Gravel-Mulched(MGM) > Old GravelMulched(OGM) > CK. Coefficient variation of the gravel-mulched fields were less than 10%, indicating a weak variability. The best models for fitting the semi-variograms were exponential, spherical, and Gaussian models depending on the soil layer and field. Spatial autocorrelation of SWC was strong in the new gravel-mulched field, moderate in the middle gravelmulched field, and weak in the bare land and old gravel-mulched field where random variation dominated. The SWC distribution obtained by Surfer8.0 showed that isoline of the layer Ⅲ was the densest followed by the layer Ⅰ and Ⅳ, with the layer Ⅱ being the most sparse, which agrees with the results of C v and C0 /(C0+ C). This provided a theoretical basis for ecological agriculture production in gravel-mulched fields.更多还原