【作者】 李春光；

【导师】 蔡崇法；

【作者基本信息】 华中农业大学 ， 资源环境信息工程， 2009， 硕士

【摘要】 随着城市扩张,城市周边的农用地逐渐转变为城建用地或待建用地,城乡交错带土壤深受影响,其内部养分要素的分布以及空间变异性都发生了很大的变化。由于城乡交错带内城区、城市边缘区以及农村土壤的功能各不相同,所以开展城乡交错带土壤养分要素分布及变异特征的研究,不仅是合理确定城市扩张过程中土壤资源利用方式的必要前提,同时也是周边农村区域土壤养分精准管理和高效施肥实践的基础。武汉市近几年来城市扩张速度进一步加快,因此本文选取武汉市东湖新技术开发区这一典型的城乡交错带作为研究区,对该区域土壤的有机质、全氮、全磷、速效钟和有效磷等5种养分要素的分布情况以及空间变异特征进行了研究。主要研究内容和结果如下:(1)综合运用GIS技术、地统计学和景观生态学分析方法,分析了研究区的景观特征,利用“断裂点”法对研究区内部城区、城市边缘区以及农村的范围进行了初步划分,提出对划分结果进行优化的方法,在确定城区、城市边缘区以及农村范围的基础上,划分出不同的土壤功能区。(2)分析了不同土层深度土壤养分要素的分布特征。结果表明,在自然和人为因素的双重影响下,随着深度的增加,全氮、全磷、速效钾、有机质以及有效磷含量的均值都呈现出下降的趋势,而且降幅逐渐减小。其中有机质降幅相对比较高,而全磷和有效磷含量的降幅相对比较小。研究区土壤养分含量主要富集在浅表层。(3)对比分析了土壤养分要素在城区、城市边缘区、农村三个土壤功能区不同层次含量分布特点。结果表明,农村和城区土壤有机质含量普遍高于城市边缘区。城区全氮含量普遍高于其他区域。全磷含量在城区浅层有一定量的聚集,其他土层和区域含量比较均衡。速效钾含量在三个区域内的变化不明显,整体分布相对比较均衡。城区土壤有效磷含量普遍高于农村和城市边缘区。另外土地利用方式对土壤养分含量也有一定的影响,分析结果显示,有机质在林地和耕地中的含量较高,而城建用地以及待建用地有机质含量相对较低,耕地中的全氮含量总体较其它用地类型要少。全磷、速效钾以及有效磷在各种用地类型中的含量分布比较平均,差异不明显。(4)探讨了研究区内土壤养分要素的空间变异特征,结果表明,不同土层不同养分要素的空间变异特征并不相同,且有些要素的分布在强烈的人为作用下不服从内蕴假设的半方差分析前提,但总体来看,0-10cm土壤要素的空间分布相对比较均一,主要是由于第一层土壤裸露于地表,受到持续强烈的人为作用的影响比较显著,使得土壤要素原有的空间变异特征逐渐减弱。10-20cm和20-40cm土壤受人为作用的影响较小,土壤母质、气候等结构性因素对土壤空间变异的影响明显,空间变异性增强。更多还原

【Abstract】 With urban expansion,peri-urban agricultural land gradually convert to urban land be constructed or urban land,soil in Urban-rural ecotone are affected by urban expansion, the internal elements of the distribution of nutrients and the spatial variability have great changed in this place.Distribution and spatial variability of internal Nutrient elements of its are great changed.As a result of the city,urban fringe and rural soils have different functions,so study on the soil nutrient distribution and variation characteristics of Urban-rural ecotone not only reasonable to determine the process of urban expansion in the use of soil resources necessary precondition,but also soil nutrient management and efficient fertilizer precise basis of practice.Wuhan City in recent years to further accelerate the speed of urban expansion,so this paper select Wuhan East Lake New Technology Development Zone as research object, study on the distribution of nutrient elements and spatial variability characteristics of soil organic matter,total N,total P,available K and available P,The main research content and results are as follows:(1) Comprehensive use of GIS technology,landscape ecology and statistical analysis methods,analysis of the landscape characteristics of the study area,by using the "breaking point" method to initial divide urban areas,urban fringe and rural areas of the study area,and put forth a optimization methods,based on in determining the urban areas, urban fringe and rural areas to divide of the different functional areas of the soil.(2) Analysis soil nutrient distribution of elements at different depths of research area. The results show that natural and human factors in the double impact of the increase with depth,total N,total P,available K,organic matter and available P content of the average downward trend has emerged,and gradually increasing reduction.Which increase soil organic matter decrease with the relatively high,and total P and available P content of the drop is relatively small.Soil nutrient content of the study area in a shallow surface enrichment.(3) Comparative analysis of the soil nutrient elements in urban areas,urban fringe, rural areas in three different levels of soil functional distribution of the content.The results show that rural and urban areas of soil organic matter content is generally higher than urban fringe.City total N content is generally higher than other regions.Total P concentration in urban areas have a certain amount of shallow gathered,other soil and a more balanced regional content.K content in the three regions did not change significantly,the overall distribution is balanced.City soil available P content is generally higher than rural and urban fringe.Land use patterns on soil nutrient content will have an appreciable effect,the results of the analysis show that the organic matter in wood land and arable land with a high level,and urban construction sites and construction sites to be relatively low organic matter content,total N content of arable land in general less than other land types.Total P,available K and available P in a variety of land types was rather evenly distributed among the content,the difference was not obvious.(4) Study the spatial variability of soil characteristics of the region,results showed that the different layers of different elements of the spatial variability of nutrients is not the same as the characteristics and distribution,in the role of strong man-made some elements is not subject to the assumption of intrinsic which is the premise of semi-variance Analysis,but overall,0-10cm of soil spatial distribution is relatively homogeneous,mainly due to the first layer of soil exposed at the surface,by the continued and strong role of man-made impact is more prominent,making elements of the original soil spatial variability Characteristics slowing down.10-20cm and 20-40cm of soil by man-made impact is smaller,soil parent material,climate and other structural factors impact are enhanced on spatial variability.更多还原