中文摘要：

为揭示微尺度膜下滴灌农田土壤水盐的空间变异特性，通过大田试验，采用经典统计和地质统计方法，研究了3种微尺度（0．25m、1m和4m）和不同土层深度棉田土壤水盐的空间变异性，并确定其合理取样数。结果发现，3种微尺度下，土壤含水量的变异强度为中等偏弱，其变异性随尺度增大而增强，随深度增加呈先增强后减弱趋势。土壤含盐量的变异强度为中等偏强，其变异性随尺度增大而增强，随深度增大呈先减弱后增强趋势；3种尺度和不同深度条件下，土壤含水量和含盐量的半方差函数大部分可采用高斯模型模拟，且精度较高；样品的合理取样数为367个。研究结果可为制定膜下滴灌土壤水盐的监测方案和调控措施提供理论指导。

英文摘要：

To explore spatial variability of agricultural soil moisture and salinity on microscales under mulch drip ir- rigation, we conducted filed experiments and employed classical statistics and geostatistics to investigate the spatial variability of soil moisture and salt content in cotton field on three microscales （0.25 m×0.25 m, 1 m×1 m, and 4 m× 4 m） and in different soil depths and determine the reasonable sampling number. The results indicated that the variability of soil moisture was moderate and relatively weak on three microscales, which was enhanced as scale increased and enhanced first and then weakened as depth increased. The variability of soil salinity was moderate and relatively strong, which was enhanced as scale increased and enhanced first and then weakened as depth increased. On three microscales and in different depths, most semi-variograms of soil moisture and salinity could be simulated by Gaussian models with high accuracy and the reasonable sampling number should be 367. The results could provide theoretical guidance for developing monitoring scheme and control measures for soil moisture and salinity under mulch drip irrigation.