宁夏中部旱作区耕地土壤养分空间变异及评价

发布时间：2018-05-17 04:11

本文选题：土壤养分 + 空间变异　；参考：《宁夏大学》2015年硕士论文

【摘要】：土壤养分的科学管理,能避免不必要的浪费；对土壤养分空间变异的研究,提供多方面的数据信息,能为在农作物种植过程中准确施肥,合理实施精准农业提供了理论基础。土壤养分在空间不同位置上产生的变异,是土壤诸多属性空间变异的重要一方面。在GIS诸多功能中空间分析工具有助于制图,地统计学的空间数据分析模块有助于数据分析,二者的功能相互结合,能把原本抽象的理论转化为能够解决实际问题的简单而快捷图像和模型,使土壤养分空间变异性的研究更加快捷、准确,并且能够生动直观的解释其原理。研究通过利用GIS和地统计学方法,分析研究了宁夏旱作节水农业科技示范区(同心县王团)的土壤养分分布特征及空间变异规律,并对土壤养分丰缺状况进探究,对土壤养分的综合水平进行评价,研究的结果如下：(1)在土壤养分中pH在变异系数上的值最小为4%,而速效磷的变异系数值最大为61%,总的变化规律从全磷、速效钾、碱解氮、全氮、全盐到有机质依次减小。(2)土壤养分之间的相关性分析主要说明各指标之间联系的紧密程度和相互作用程度。全氮与有机质、pH、全磷、碱解氮、速效磷之间没有显著地相关性。全磷与速效磷、全磷与速效钾之间的相关性不显著,其余的均为为极显著相关性。其中,碱解氮与全盐的相关系数为0.601,碱解氮与pH的相关系数为0.662,均表现出极显著的相关性。(3)有机质、pH、全磷、碱解氮、速效磷、全氮、全盐、速效钾均在一定的范围内存在空间相关性,它们之间的空间变异性不同,其变程范围在74m—2110m。碱解氮和全磷的变程值最大为2110m,全氮的变程值最小为74m,其余几种养分的变程值的大小依次为全盐pH速效钾速效磷有机质。(4)从pH空间分布图中可知,由于pH的变化范围不大,导致其在空间分布图上表现出的变化梯度不大。土壤速效氮含量从东到西的递减规律。全氮的含量表现出中部区域含量较低,东西部含量较高的规律；全磷含量北部地区高于南部地区,各等级分布比较分散,大部分分布在南部地区,而全磷含量比较高的分布在中部地区；速效磷含量其分布规律为北部地区高于南部地区,东部地区高于西部地区,有三个分散的小区域速效磷含量非常高；速效钾含量北部明显高于南部,南部绝大多数研究区域土壤肥力低于国家三级标准,东北部含量较丰富；在该研究区域内,有机质的含量比较均匀,空间变异不大,只有中西部地区有机质含量相对较低；土壤全盐的含量北部地区高于南部地区,尤其是北部地区规律非常明显,自东向西逐级递减,而南部地区的中间一块区域的含量明显低于四周区域的含量。(5)土壤机械组成(砂粒、粉粒、粘粒)和土壤养分含量之间的进行了相关性分析,表明土壤中的有机质、全氮、速效钾、全盐、速效磷、碱解氮的含量的分布,都与颗粒组成的空间分布有密不可分的联系。(6)土壤养分综合评价空间分布,东北部地区土壤养分综合水平较高的B等地占研究区面积的38.4%,而西南部地区是C等地所占面积59.18%,A等地只是占东北角的一小块区域和其周围的几个点状区域,其面积只占总面积的0.02%。
[Abstract]:The scientific management of soil nutrients can avoid unnecessary waste, and the study of spatial variability of soil nutrients provides many data information, which provides a theoretical basis for accurate fertilization in the process of crop cultivation and the rational implementation of precision agriculture. The variation of soil nutrients in different space positions is a lot of soil properties space. An important aspect of variation. In many GIS functions, spatial analysis tools help to map. The spatial data analysis module of geostatistics contributes to data analysis. The functions of the two are combined, and the original abstract theory can be transformed into simple and fast images and models that can solve practical problems, so that the spatial variability of soil nutrients can be studied. By using GIS and geostatistics, the characteristics of soil nutrient distribution and spatial variation in Ningxia's dry farming and water-saving agricultural science and technology demonstration area (Tongxin county) were studied by using the method of geostatistics, and the comprehensive level of soil nutrients was explored and the comprehensive level of soil nutrients was studied. The results are as follows: (1) the minimum value of the variation coefficient of pH in soil nutrients is 4%, while the maximum variation of available phosphorus is 61%. The overall change rules decrease in turn from total phosphorus, available potassium, alkali hydrolysable nitrogen, total nitrogen, all salt to organic matter. (2) the correlation analysis between soil and soil nutrients mainly illustrates the relationship between the indexes. There was no significant correlation between total nitrogen and organic matter, pH, total phosphorus, alkaline nitrogen and available phosphorus. The correlation between total phosphorus and available phosphorus, total phosphorus and available potassium was not significant, and the rest were significantly correlated. The correlation coefficient of alkali hydrolysable nitrogen and total salt was 0.601, and the correlation coefficient of alkali hydrolysable nitrogen and pH was 0.662, they all showed significant correlation. (3) organic matter, pH, total phosphorus, alkali hydrolysable nitrogen, available phosphorus, total nitrogen, total salt, and available potassium exist in a certain range of spatial correlation, the spatial variability between them is different, the range of variation range in the range of 74m 2110m. alkali solution nitrogen and total phosphorus is 2110m, and the minimum variation range of total nitrogen is 74m, The change range of the remaining nutrients is in turn the total salt pH available potassium available phosphorus organic matter. (4) from the pH spatial distribution map, it is known that because of the small change range of pH, the change gradient in the spatial distribution map is not large. The content of soil available nitrogen decreases from East to west. The content of total nitrogen shows the content in the middle region. The content of total phosphorus in the northern region is higher than that in the southern region. The distribution of total phosphorus in the southern region is relatively scattered, most of which are distributed in the southern region, while the total phosphorus content is high in the central region. The distribution regularity of the content of available phosphorus is higher in the northern region than in the south, and in the East is higher than that in the western region, with three points. The content of available phosphorus in the scattered area is very high, the content of available potassium in the north is obviously higher than that in the south, and the soil fertility in most of the research areas in the south is lower than the national standard of national three, and the content of the northeast is rich. In this study area, the content of organic matter is relatively uniform and the spatial variation is not very large, only the organic matter content in the middle and western regions is relatively low. The content of all soil salt in the north is higher than that in the south, especially in the northern region, which is obviously decreasing from east to west, and the content of the middle part of the south area is obviously lower than that in the surrounding area. (5) the correlation analysis between soil mechanical composition (sand, powder, clay) and soil nutrient content is analyzed. The distribution of organic matter, total nitrogen, available potassium, total salt, available phosphorus, and alkali hydrolysable nitrogen content in the soil have an inseparable relation with the spatial distribution of grain composition. (6) the comprehensive assessment of spatial distribution of soil nutrients, the high comprehensive level of soil nutrients in the northeast area of B and other areas account for 38.4% of the area of the study area, and the southwest region is the area of C and so on. The area is 59.18%, A and other places are only a small area of the northeast corner and a few punctuate areas around it, which occupy only 0.02%. of the total area.
【学位授予单位】：宁夏大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S158

【参考文献】