【作者】 李晓霞；

【导师】 胡振华；

【作者基本信息】 山西农业大学 ， 农业推广硕士（专业学位）， 2016， 硕士

【摘要】 在农田土壤墒情监测过程中,确定合理的测墒点数量及位置对该区域土壤墒情的精确获取影响较大,由于农田土壤含水率客观存在着空间变异性,所以在确保一定墒情监测精度的条件下,通过科学合理的方法来确定农田土壤含水率测墒点的合理数量和位置显得至关重要。本文借助Spss19.0、Arcgis10.2、Surfer12.0等软件利用经典统计学和地统计学等原理,在中国水利水电科学研究院大兴试验基地进行了试验研究,分析了试验区典型农田土壤水分的空间变异规律,探索了试验区典型农田土壤含水率的合理测墒点数量和位置。主要结论有：(1)通过对试验区土壤质地及特征曲线的测定分析,得知试验区冬小麦农田土壤质地主要为砂质壤土,其中不同深度处存在壤质砂土,粉砂质壤土和壤土等土层：还得知土壤质地变化较大的地块土壤含水率变异性也较强,而土壤质地较为均一的地块土壤含水率变异性则较弱。(2)农田不同深度土壤含水率均符合正态分布；随着深度的加深,农田土壤水分空间变异性呈先增强后减弱的趋势;且其中0-10cm、10-20cm、60-70cm、70-80cm 90-100cm深度土层的土壤水分变异程度基本为弱变异;30-40cm,40-50cm,50-60cm深度土层的土壤水分变异程度基本为中等变异,而20-30cm深度土层的变异系数值有大有小变化较为复杂。(3)利用地统计学方法对试验区土壤含水率进行趋势分析,得知农田土壤含水率在沿南北和东西两方向上的变化趋势不明显；对农田土壤含水率按不同深度进行了插值分析,其中0-60cm深度土层的土壤含水率的变异性比较复杂,空间结构性一般;0-30cm及60-100cm深度的变异性较小,空间结构性显著,整体上,试验区土壤水分的空间变异性随深度的加深呈先增强后减弱的变化趋势。(4)试验区土壤含水率在90%置信水平,5%μ采样误差下的合理采样数目为3个。(5)试验区土壤含水率的空间相关域为21m,在90%置信水平,5%μ采样误差下3个测墒点的布设位置分别为：(5,17)、(26,11)、(47,14)。更多还原

【Abstract】 In the process of monitoring soil moisture, there has a great influence to determine the number of reasonable monitoring sites and the optimal coordinates. Due to the factor of spatial variability, under the condition of a certain monitoring accuracy, there are crucial through scientific and reasonable method to determine the number of reasonable monitoring sites and the optimal coordinates.With the help of Spss19.0, Arcgis10.2, Surfer 12.0 software and the theory of classical statistics and geostatistics, analyze the typical spatial variability regular of experimental area; explores the number of reasonable monitoring sites and the optimal coordinates in the China Water Resources and Hydropower Research Institute of DaXing experimental base. The main conclusions are as follows:(1)Through the analysis of the characteristic curve and soil texture in experimental area, learned that the sandy loam are mainly soil texture in winter wheat farmland of experiment site, in which have loamy sand, silty loam, and loam in different depth soil; Also learned that in the larger plot soil texture changes range, the variability of soil moisture content is stronger, within the scope of relatively uniform soil texture, that the variability is weaker.(2) The soil moisture content data conforms to normal distribution in different depth of farmland, with the deepness of soil deepen, the spatial variability of soil moisture content all show a trend of first increases and then decreases. And in 0-10cm、10-20cm、60-70cm、70-80cm 90-100cm depth spatial variability of soil moisture content is the weak variation; And 30-40cm,40-50cm,50-60cm depth is medium variability, but 20 to 30cm depth spatial variability of soil moisture content is the complex variation.(3) Making use of statistical methods to analysis the Experimental zone soil moisture content trend, learned that in two direction along the north-south and east-west trend is not obvious. For the interpolation analysis according to different depth of soil moisture content, including 0 to 60 cm depth of variability of soil moisture content is more complex, the space structural general,0-30 cm and 60-100cm depth of variability is small, space structural significantly. Overall, with the deepness of soil deepen, the spatial variation of soil moisture show a trend of first increases and then decreases in experimental zone.(4) At the same confidence level, the number of reasonable monitoring point decreases with the increases of sampling error. At the same sampling error, the number of reasonable monitoring point decreases with the lower of confidence level. At 90% confidence level,5% μsampling error conditions, the number of reasonable monitoring experimental area is three;(5) The spatial correlation of soil moisture content is 21m in experimental zone. At 90% confidence level,5% μ sampling error conditions, the exact location of the three monitoring point respectively is (5,17)、(26,11)、(47,14).更多还原