辽河流域土地适宜性地球化学研究

发布时间：2018-06-27 02:52

本文选题：辽河流域 + 土地适宜性　；参考：《东北大学》2013年博士论文

【摘要】：土地适宜性评价是根据人类要求、意愿或一些未来活动的预测而确定土地利用最适合的空间模式,它是土地利用总体规划的基础。辽河流域位于辽宁省中部,是辽宁省主要商品粮基地和粮食作物稳产高产区。由于快速发展工农业,多年来接纳流域内的工业、农业和生活的废水、固体废弃物以及风化产物,使其土壤元素地球化学性质发生了较大的变化,并进一步降低了土地质量,这成为限制区域发展的一个重要因素。本文以地球化学原理为基础,基于GIS平台,通过因子分析、地统计学和模糊数学等方法和手段,对辽河流域深、表层土壤元素地球化学分布规律、辽河流域土地条件及辽河流域地球化学特征的影响因素进行研究,取得了如下成果： 1)通过对辽河流域土壤中54种元素进行因子分析：共获得深、表层土壤各8个主因子,其中因子1的元素较多,为自然风化的结果,各主要元素含量整体分布具有明显的“U型分布"的特征；因子2和因子3的较大载荷元素的重金属元素分布特征明显受人为因素的干扰,较大载荷的N元素等与有机质的含量分布有密切的关系；其它因子的一些元素等在滨海盐土或受海水盐化作用的土壤中含量较高和在潮土、风沙土区含量高,土壤沙化造成钾元素含量增高。 2)通过地统计分析得出,辽河流域表层土壤中的元素在空间分布上存在不同程度的差异：营养元素Ca、Mg、P和必需元素Fe、 Mn、Zn、Cu、B、Si及重金属元素Cr和Ni具有强烈的空间自相关性,主要受结构性因素的影响,其它的营养元素、必需元素和重金属元素其空间变异性是随机性因素和结构性因素共同影响的结果；其中重金属元素As、Cd、Pb和Hg的空间变异性比较相似,主要受随机性因素的影响。 3)以辽河流域表层土壤54项元素及测试指标为依据,以自组织特征影射(SOM)神经网络为基础,结合C—均值分类结果,把河流域表层土壤分成五大区：A区土壤的有机质含量高,N和P含量充足,各种微量元素含量均衡且有较高的含量水平,土壤肥沃。B区—低丘元素含量均衡地球化学区：除Cd、Cl、I以外,B区土壤元素的含量与其它自然成因土壤类型相比都处于中等水平。C区土壤最突出特征是硅、钾含量高,多数大量元素和微量元素含量低,农作物所需的营养元素含量低,是极度贫瘠的土地。D区是滨海高卤族元素地球化学区。E区土壤是受人为因素影响或干扰形成的具有较高污染重金属元素含量的土壤。 4)辽河流域土地整体环境质量评价得出：辽河流域土地整体环境质量状况良好：洁净无污染的一级土壤面积较大,占87.88%,是可以作为农业生产使用的安全土壤区；辽河流域土壤污染区集中在沈阳和锦州两个区域,以Cd元素为主要污染因素,其次为Hg、Pb和Zn。 5)辽河流域土壤营养状况进行综合评判得出：辽河流域土壤营养状况令人担忧：“很富足"土壤和“富足”土壤面积累计仅占2.30%；适中土壤占11.62%；相对缺乏面积占45.57%；缺乏面积占31.94%；“很缺乏"面积占到8.55%。仅有不足15%左右的土壤能满足耕种的基本需要。 6)通过对辽河流域主干河底积物和浅海沉积物的元素地球化学特征和因子分析得出：主干河底积物重金属元素Cr、Cu、Hg等和营养元素N、P的整体含量较高,主要集中在浑河沈阳及太子河鞍山周边水系中；浅海沉积物的Cd、Hg、Pb和Zn沉积物主要表现为西高东低、滨海高深海低的特点,高含量区集中在锦州湾—葫芦岛连山湾一带。同样,Pb、Cu、Mo、As、Sb、S、Ag平均含量均高于中国浅海沉积物平均组成,并都表现出表层富集的特征。另外,对典型矿山和城市工业区的元素地球化学特征分析得出,矿山开采和城市工业化也改变了当地土壤的元素组成,造成了重金属元素的富集及污染,影响了流域生态环境。 7)基于GIS平台,利用因子分析和CIA方法研究辽河流域深、表层地球化学特征和深、表层土壤风化程度得出：辽河流域土壤的风化程度很低,在空间上存在一定差异,但是表层和深层土壤风化的程度差异并不大；受风化程度和人为因素的影响,辽河流域土壤表层的营养元素含量相对增加,重金属元素分布特征受人为因素干扰大,在城市区和工矿区的表层土壤中含量相对较高。
[Abstract]:Land suitability evaluation is the most suitable space model for land use according to human requirements, wishes or some future activities. It is the basis of the overall planning of land use. The Liaohe River Basin is located in the middle of Liaoning province. It is the main commodity grain base in Liaoning and the stable and high yield region of grain crops. To accept the industrial, agricultural and living waste water, solid waste and weathering products in the basin, the geochemical properties of the soil elements have been greatly changed, and the quality of the land is further reduced. This has become an important factor in limiting the development of the region.
Based on the principle of geochemistry, based on the GIS platform, by means of factor analysis, geostatistics and fuzzy mathematics, the geochemical distribution of the surface soil elements in the Liaohe River Basin, the land conditions of the Liaohe River Basin and the geochemical characteristics of the Liaohe River Basin are studied. The following achievements have been obtained.
1) through the analysis of the factor of 54 elements in the soil of the Liaohe River Basin: a total of 8 main factors in the surface soil, of which there are more elements of factor 1, which is the result of natural weathering, the overall distribution of the main elements has the characteristics of "U type distribution", and the distribution of heavy metal elements in factor 2 and factor 3 is special. The N elements of large loads are closely related to the content distribution of organic matter, and some elements of other factors are high in the coastal saline soil or in the salty soil, and in the tidal soil, the content of the sandy soil area is high, and the soil desertification causes the increase of the potassium content.
2) according to the statistical analysis, the spatial distribution of elements in the surface soil of the Liaohe River Basin has different degrees of difference: nutrient elements Ca, Mg, P and essential elements Fe, Mn, Zn, Cu, B, Si and heavy metal elements Cr and Ni have strong spatial autocorrelation, mainly influenced by structural factors, other nutrients, essential elements and heavy elements. The spatial variability of metal elements is the result of the combination of random factors and structural factors, and the spatial variability of heavy metal elements As, Cd, Pb and Hg is similar, mainly influenced by random factors.
3) on the basis of 54 elements and test indexes of surface soil in the Liaohe River Basin, the surface soil of the river basin is divided into five areas based on the self organizing feature projection (SOM) neural network and combined with the C mean classification results. The soil organic matter content of the A area is high, the content of N and P is sufficient, the content of various trace elements is balanced and the soil has a high level of content. The soil fertility.B area and low hilly element content equalizing geochemical area: except Cd, Cl, I, the content of soil elements in B area is in the middle level.C area compared with other natural origin soil types, the most prominent characteristics are silicon, high content of potassium, the low content of large amounts of elements and trace elements, and low content of nutrient elements needed for crops, which is extreme. The.D area of the barren land is the soil in the.E area of the high halogen element geochemistry area of the coastal area, which is influenced by human factors or interfered with the heavy heavy metal element content of the soil.
4) the overall environmental quality of the Liaohe River Basin has been evaluated as follows: the overall environmental quality of the Liaohe River Basin is in good condition: the clean and pollution-free first grade soil area is larger, accounting for 87.88%, and it is a safe soil area used for agricultural production; the soil pollution area of the Liaohe River Basin is concentrated in two regions in Shenyang and Jinzhou, with Cd elements as the main pollution. Dyeing factors, followed by Hg, Pb and Zn.
5) the comprehensive evaluation of the soil nutrition status of the Liaohe River Basin shows that the soil nutrition status of the Liaohe River Basin is worrying: "very rich" soil and "rich" soil area is only 2.30%; moderate soil accounts for 11.62%; the relative lack area accounts for 45.57%; the lack of area accounts for 31.94%; the "very lack" area accounts for only less than 15% left 8.55%.. The right soil meets the basic needs of farming.
6) through the elemental geochemical characteristics and factors analysis of the main river sediments and shallow sediments in the Liaohe River Basin, it is concluded that the main heavy metal elements Cr, Cu, Hg, and nutrient elements N and P are higher in the main river sediments, mainly concentrated in the water system around Shenyang and Anshan of the Taizi River, and Cd, Hg, Pb and Zn sediments in the shallow sea sediments. The main features are West High East low, high sea and low sea level, high content area concentrated in Jinzhou Bay Huludao Lianshan Bay area. The average content of Pb, Cu, Mo, As, Sb, S, Ag is higher than the average composition of the sediments in the shallow water of China, and shows the characteristics of the surface enrichment. Besides, the geochemical characteristics of the typical mines and the urban industrial areas are characterized. The analysis shows that mining and urban industrialization have also changed the element composition of the local soil, resulting in the enrichment and pollution of heavy metal elements, affecting the ecological environment of the basin.
7) based on the GIS platform, we use factor analysis and CIA method to study the depth of the Liaohe River Basin, the surface geochemical characteristics and depth, and the weathering degree of the surface soil: the weathering degree of the soil in the Liaohe River Basin is very low, and there is a certain difference in the space, but the degree of weathering in the surface and deep soil is not very different; the degree of weathering and the human factors are influenced by the degree of weathering and the human factors. The content of nutrient elements in the soil surface of the Liaohe River Basin is increased relatively, the distribution characteristics of heavy metals are greatly disturbed by human factors, and the content of the surface soil in the urban area and the industrial and mining areas is relatively high.
【学位授予单位】：东北大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：X144;P208

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