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properties of soil相关的网络例句

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The process of ecological degradation in the vicinity of Shaoguan Pb/Zn smelter may be summed as: heavy metals and acidic deposits from the waste gas from smelter resulted in the vanishment of the sensitive plant species, increasing accumulation of heavy metals in soils and acidification of topsoil worsened the chemical properties and then shallow-rooted plant, mainly the herbaceous, vanished. With the demolishment of the vegetation cover, increasing water-soil erosion worsened physico-chemical properties of soil and, subsequently, some woody plants disappeared and barren land was finally appeared.

该生态系统的退化过程可以归纳为:来自于冶炼废气的重金属和酸沉降导致了敏感植物的消亡,丧失了对土壤的缓冲保护作用;重金属在土壤表层的积累,酸性物质在土壤表层的增加导致的土壤酸化以及由此引发的有机质与养分的淋溶和重金属及Al的活性增加,加剧植被的快速退化,特别是浅根植物的衰亡;地被层的破坏,导致水土流失和土壤侵蚀加深,进一步恶化表层土壤的理化性质,一些木本植物随之消失,最终形成光板地。

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。

Then it is firstly and systematically presented the layered compressible data of borehole extensometer in Changzhou area from 1984 to 2002 in this paper. Based on the Characteristics of Aquifer system and properties of soil layers, the porous soil layer in the research area is divided into four different compressible layers.

中文摘要:系统分析了常州地区地下水开采动态和地面沉降发生发展历史,概述了研究区地面沉降的框架,在此基础上,系统研究了常州市分层标从1984 年至2002 年的分层沉降资料。

On the structural properties of soil-cement mixtures and to expect to obtain important conclusions for soil-cement application not only to the attached construction of on-going project of but to other future soil-cement application where soil-cement, as an alternative to rock riprap for slope protection, is not locally available.

期能获得相关研究成果,以提供执行中之湖山水库计画,在其附属工程方面之应用,或者作为日后其他水库工程计画案,在大坝坡面保护工之抛石材料不易取得时,当作替代方案之规划设计参考。

The research is about the reuse of urban sewage for virescence irrigation, and the influence of sewage irrigation on eco-environment such as soil, plant, etc. is studied. Under the condition of field sewage irrigation, the transport and transformation and accumulation mechanism of heavy metals, nutrients and organic pollutants as vaporizable hydroxybenzene etc. in the soil-plant system are analyzed. The heavy metal pollution is evaluated by the comprehensive pollution index. The spatial variability of heavy metals in sewage irrigation area is further understood. The spatial variability of heavy metals and physical and chemical properties of soil are reflected in a more straight way by the theory model of variance function curve based on the geographical information system.

在城市污水回用于绿化灌溉对土壤、植物等生态环境的影响研究中分析了大田条件下污灌对土壤-植物体系中重金属、养分及挥发酚等有机污染物迁移转化及富集机理,对重金属污染进行了综合污染指数评价,进一步了解了污灌区重金属分布的空间异质性,基于地理信息系统提出了变异函数曲线的理论模型,更直观地反映出了重金属元素与土壤理化参数的空间变异特征。

Based on soil desertification between agriculture and husbandry interlace zone in north of Shannxi Province, on the basis of theories of landscape ecology、land resource and principle of soil genesic science, through field surveying data and indoor analyzing, the properties of soil physical, chemical and biological characteristics are systemic analyzed about desertification soil of different vegetation cover rate and type, achieving primary achievements and important evolves are as follows:Ⅰ.

本研究基于当前全球荒漠化危害现状及国内外荒漠化防治中恢复生态学的发展需要,以陕北农牧交错带土地荒漠化问题为研究对象,应用景观生态学理论、土地资源学和土壤发生学的基本原理,在野外考察、资料收集和室内测定分析的基础上,对不同植被盖度和植被类型荒漠化土地的土壤理化性质和生物学性质进行系统分析,取得的主要成果如下: 1。

Flooding,as a kind of disturbance events,occurred with higher and higherfrequency over the world.To investigate the effects of flooding disturbance ongrassland vegetation and the soil,a comparatively thorough study was conducted onAneurolepidium chinense grassland in Songnen plain,Northeast China.The studysite was located in Sanjiadian National Rangeland in the territory of Da'an city,Jilirprovince,which was partly flooded in 1998.On the study site,Several transectssubjected to different flooding durations and intensities were designed for thecomparative study among them on such aspects as vegetation characteristics,seedbanks,vegetative propagation of rhizomatous plants,distribution patterns ofpopulations,interspecific relations,and physio-chemical properties of soil.Theresults were as follows:(1)Of the functional group composition of the vegetation,with the elongation of the flooding duration or the increase of flooding severity,theratio of hygric and hygro-mesic plants increase,while that of mesic and mesoxericplants decrease,of Therophytes changed unimodally,of Geophytes increased,whileof Hemicryptophytes decreased.

为弄清草地植被及其土壤环境对水淹干扰的响应,在松嫩平原羊草草地1998年部分遭受水淹的吉林省大安市三家甸子草场内设置了经历不同水淹干扰持续时间和不同水淹强度的样带,并在这些样带之间从植被特征、种子库特征、根茎植物的营养繁殖性能、种群分布格局、种间关系及土壤的理化性质等多个方面展开对比研究,主要结果如下:(1)在植被的功能群组成中,随干扰强度的增加和水淹干扰持续时间的延长,湿生、湿中生类植物功能群的优势度比例基本上是逐渐增加的,中生、中旱生类植物功能群的优势度比例则逐渐减小,而一年生植物的优势度比例呈单峰型变化,地下芽植物比例增加,地面芽植物比例减小。

Applying desulphurization by-product properly can reduce soil bulk density, improve soil structure, increase soil permeability and improve the physical properties of soil moisture, reduce pH, ESP, TDS and improve the sodic soil physical and chemical properties.

脱硫副产物能降低土壤容重,改善土壤结构,增加土壤通透性,改善土壤水分物理性状,中和土壤碱性,降低土壤pH值和碱化度,降低土壤的全盐量,从而达到改良碱化土壤的作用。

On the basis of the analysis of physicochemical properties of soil, analyzes variance characters of soil physical properties and nutrient properties in different land use ways and slope locations in the western edge mountains of Sichuan basin, and the results indicate that, in the respect of soil physical properties, it is either the soil structure coefficient or the degree of aggregation that is contained in farm land is obviously less than that is contained in reforested land and waste land, and because of the effects that forest crop root system and forest floor take, the soil physical properties of forest plantation is far better.

在土壤理化指标测定基础上,分析了四川盆地西缘中低山坡地不同土地利用方式和坡位下土壤物理性质与养分性质的分异特征,结果表明:土壤物理性质方面,耕作土壤的结构系数和团聚度明显低于人工林和荒草地,人工林由于林木根系和枯枝落叶层的作用,土壤物理性状明显较好。

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。

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