土壤性质

In order to find out completely the soil-wheat contaiminated by heavy metals in Tianjin sewage farm, we collect samples on the dry land and examinate contents of heavy metals in soil-wheat system. Firstly, the anthor evaluates that soil irrigated by sewage that has been contaminated slightly, the main polluting factors are Cd and Zn, and then the anthor evaluates soil according to different regions, soil types and irrigating water. Secondly, the anthor analyzes content and enrichment ability of heavy metals in different part of wheat, evaluates wheat is contaiminated by Cd widespreadly, only few samples polluted by Zn.Finally the anthor put up correlative analysis about heavy metal contents in the soil-wheat system, as well as plant enrichment coefficient and some physico-chemical properties of soil, and establishes a prognostic model about heavy metal content among wheat spike, soil, soil types, PH, organic matter and salinity with the quantifying theory.The prognostic accuracy of primarily contaminative factors is the best with compound correlative coefficient examining, the model can be founded.With improvement of living level, people need cleaner food.

为全面了解天津市污灌区农产品生产地土壤和旱地作物小麦的重金属污染状况，我们于2004～2005年对全市污灌区的土壤和小麦进行了采样，在对该区土壤—小麦系统中六种重金属元素(Cd、Cu、Pb、Zn、Cr和Ni)的含量进行检测的基础上，本文首先分析评价了污灌区农田土壤的环境质量总体已达到了轻度污染水平，主要的污染因子是Cd和Zn，同时对污灌区农田土壤分区县、土壤类型和不同灌水类型进行了评价；然后分析了重金属在小麦不同部位的含量与富集能力，评价了污灌区旱地作物小麦普遍遭受了Cd的污染，只有个别样点遭受了Zn的污染；最后对土壤—小麦系统重金属含量间以及植物富集系数与土壤部分理化性质间进行了相关分析，由于土壤类型是定性变量，本论文以数量化理论建立了小麦穗实中重金属含量与土壤中重金属全量、土壤类型、PH值、有机质和全盐量间的预测模型，经复相关系数检验，污灌区主要的污染因子Cd和Zn的预测精度最高，模型可以成立。

Phase 1 started with field pea followed by spring wheat whereas phase 2 started with spring wheat followed by field pea.The objectives of this thesis are:1 to quantitatively analyze effects of soil chemical,physical and biological properties on soil quality and productivity under different tillage systems and the driving factors for the changes of soil quality under tillage in a long-term,2 to select the best soil quality assessment indicators,and 3 to establish soil quality assessment models that are suitable for the erodible environment of semi-arid region on the Loess Plateau.

通过分析3个轮作周期不同耕作方式下土壤理化性质、生物性质和生产力对土壤质量的影响，阐明长期耕作过程中土壤质量的演变特征及其驱动因子，筛选出适宜于黄土高原半干旱区侵蚀环境下土壤质量评价的代表性指标；并综合前人的研究，结合区域特点，建立适宜于黄土高原半干旱区侵蚀环境的土壤质量评价模型。

However,the removal of soil noncrystalline aluminum with DCB soultioncaused an obvious decrease of soil SSA.3.The hydroxy aluminum in the interlayer of 1.4nm intergrade mineralhad an important negative effect on the cation exchange capacity ofsoil colloids.Its removal would cause a significant increase in CEC valuesof the soil colloids.4.Free aluminum was the major carrier of phosphate adsorption of soilcolloids.Particularly,the active aluminum had a decisive effect on thecapacity of phosphate adsorption of soil colliods.5.Addition to the effects of other soil constituents on soil surfaceproperties,it was thought that the effect of soil free aluminum,especially active aluminum on soil surface properties,deserved closeattention.

焦磷酸钠、草酸铵、DCB、柠檬酸钠和NaOH提取的土壤铝对提高土壤CECv、AEC、PZC和PZNC起重要作用，尤以活性铝的作用较大。2）用草酸铵处理除去铝后，土壤比表面积变化不大或略有增加；用DCB处理除去土壤铝后，土壤SSA明显降低。3）层间羟基铝对土壤胶体的阳离子交换量有显著负贡献，用柠檬酸钠将之除去后，土壤胶体的阳离子交换量明显增加。4）土壤胶体中的游离铝是土壤胶体吸附磷的主要载体，尤其是其中的活性铝，对土壤胶体的磷吸附能力起决定性作用。5）除其它土壤组分对土壤表面性质的影响外，土壤中的游离铝、尤其是活性铝对土壤有关表面性质的影响，值得引起特别的重视。

The content of SMBC,SMBN and mineralizable carbon 〓 in profiles of Fluvio-marine yellowsoil,Fluvio-aquie soil,Quaterary red clay were all decreased with increasing depth,but themineralizable nitrogen 〓 was not true.

相关性分析表明，葡萄糖〓在0～3d的周转速率与土壤代谢熵〓呈显著性正相关；3～28d内，葡萄糖〓周转速率与土壤理化性质和生物学性质都无显著的相关性；28～294d内，葡萄糖〓周转速率与土壤总有机碳、全氮、CEC呈显著或极显著负相关，与土壤砂粒含量呈显著性正相关。

The semivariograms of all the soil properties studied were fitted with spheric model.

各项土壤性质的变异函数都可拟合为球状模型。

Based on the data collected from samples, it was analyzed the diversity of soil animal in different using type of soils. The relationship between soil animal and soil character was discussed after measuring soil character under ways of soil using. The results indicated that there were consanguineous relationship between animal unit number and soil weight, pH value, organic matter content, full N content, full K content and quick result K content.

分析了各种土地利用方式下土壤动物的多样性；同时，对各种土地利用方式下土壤的理化性质进行了测定，探讨了土壤动物与土壤理化性质之间的关系，结果表明土壤容重、pH值、有机质含量、全N含量、全K含量和速效K含量与土壤动物的种类和数量有密切的关系。

Main contents of the course includes: related conceptions, matter of soil, soil texture, soil organic matter, soil humus, soil structure, soil moisture, soil air, soil acidity and soil alkalinity, soil colloid, cation exchange, soil former soil-forming process, soil classification, distributions and properties of soil great group in China (fores soil, steppe soil, main non-zonal soil, paddy soil, etc), soil erosion, soil contamination, soil utilization, conservation of soil resource, soil investigation, etc.

土壤地理学是地理科学专业的主要基础课程之一，是一门必修课程；要求掌握土壤地理学基本的理论、知识和方法；主要内容有：有关概念、土壤组成物质、土壤质地、土壤有机质、土壤腐殖质、土壤结构、土壤水分、土壤空气、土壤酸碱性、土壤胶体、土壤阳离子交换、土壤形成因素、土壤形成过程、土壤分类、中国主要土壤类型（森林土壤、草原土壤、主要的非地带性土壤、水稻土等）的分布及其性质、土壤侵蚀、土壤污染、土壤资源的利用与保护、土壤调查研究等。

The second method is allowed for complex geological conditions (inclined occurrence of the soil layers, the presence of karsts, frozen soil lenses, and so on) and is based on the use of more complex calculation schemes which also account for the inertia properties of the soil base.

第二种方法是让复杂的地质条件(倾向发生的土层中，在场的溶洞，冻土镜片，等)，以及基于使用更复杂的计算方案，其中还占惯性土壤性质的基地。

The co-ratio variation is the determining factor for the rank stability and spatial distribution pattern.

这些均是土壤性质秩序稳定性的决定条件。

The river bank soil nature and riverbed depth are two important factors acting on groundwater.

河岸土壤性质及河弘深度是堤内地下水的两个重要影响因素。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐