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The Farming-pastoral Zone in North China was separated into 8 Eco-regions according to the known Eco-region. The dissertation analyzed the regional differences of land use changes from three aspects on dynamic degree , land use degree and the change direction (1)On land use dynamic degree, the dynamic degree of the cropland was the highest in North warm temperate deciduous broad-leaved forest and the lowest in temperate forest steppe; forest land's was the highest in alpine meadow and the lowest in warm temperate forest steppe; grassland's was the highest in temperate forest steppe-bunchgrass steppe and the lowest in alpine meadow; other land's was the highest in North warm temperate deciduous broad-leaved forest-the Huang-Huai-hai plain and the lowest in warm temperate bunchgrass steppe.

结合已有的自然生态区的划分,将我国北方农牧交错带划分为8 个自然生态区,选取土地利用动态度、土地利用程度以及土地利用变化方向等3 个方面的指标对研究区进行了区域分异规律的研究,结果如下:(1)耕地动态度北暖温带落叶阔叶林生态区——北部山地丘陵区最大,温带森林草原生态区最小;林地的动态度高寒草甸生态区最大,暖温带森林草原丛生禾草草原生态区——东南森林草原区最小;草地动态度温带森林草原——丛生禾草草原生态区最大,高寒草甸生态区最小;其他用地的动态度北暖温带落叶阔叶林生态区——黄淮海平原区最大,暖温带森林草原丛生禾草草原生态区—西北丛生禾草草原区最小。

1Niche construction can lead to stable coexistence of diverse genotypes in spatially structured population, which supports a stable polymorphism even without heterozygote superiority.(2)With habitat deterioration, niche construction accelerates the formation of steady polymorphism and hence impedes the harmful influences of environment on the population, which might embody a life-history strategy of organism under the unfavorable environment.(3)Niche construction results in the coexistence with alternative polymorphism through genotype-environment feedback and limited gene flow.(4)The niche-constructing organism is an active force to alter its environment and hence the direction of natural selection in order to better survival.(5)Spatial dynamics and distribution pattern of metapopulation are profoundly influenced by time-lagged niche construction.(6)Metapopulation size can reach a fixed level in the recency effect and equal weighting of time lag but is statistical stability in primacy effect, which implies the primacy effect is most remarkable.(7)The increment in the relative weightingof each generation\' niche construction and the length of time lag are significant factors for system destabilization.(8)Moderate capacity of positive niche construction benefits the metapopulation persistence.(9)The narrowing of niche breadth can decrease the metapopulation size and thereby increase the extinction risk.(10)The coupled function of time lag and niche construction make the system oscillation and generate the spiral wave, spiral-broken and circular wave in heterogeneous habitat.The spatial distributions of metapopulation and resource content are complementary due to a phase lag of their both frequencies.(12)Metapopulation persistence with niche construction depends not only on the balance between colonization and extinction, but also on the balance between the ability of niche construction and natural dissipation of habitat.(13)Metapopula-tion can survive under certain condition when the percent of suitable patches in habitat is lower than the ration of extinction to colonization.(14)Two thresholds exist in the process of transition of habitat quality dynamics from unsuitable to suitable, which include the intensity of niche construction and the initial condition of system.(15)Metapopulation size is positive correlated with the ability of positive niche construction, which means that organism or population who has strongly positive influences on their environment plays an important role to maintain the available habitat.

通过上述几个方面的研究,主要得出以下15条结论:(1)生态位构建可使空间结构种群,甚至是在没有杂合子优势的条件下,形成多种可能的稳定基因型分布模式;(2)随着环境的破坏与恶化,种群的生态位构建作用加速其较早形成稳定多态以阻碍环境对种群的不利影响,解释了有机体在不利环境下的一种生活史对策;(3)生态位构建作用通过基因型—环境反馈机制及有限的基因交流导致基因型多态的稳定共存;(4)有机体的生态位构建作用是一种积极的动力改变环境进而改变其自然选择的方向;(5)生态位构建的时滞作用对集合种群动态和空间分布产生深刻影响;(6)集合种群大小在时滞的崭新效应和等权重效应下达到一固定值,而在首位效应下达到统计稳定,表明首位效应的影响最显著;(7)首位效应下生态位构建相对权重的增量和时滞的长度是影响系统不稳定性动态的关键因素;(8)适中的生态位构建强度有利于集合种群的续存;(9)生态位宽度变窄会减少集合种群的数量从而增加其灭绝风险;(10)时滞和生态位构建的双重作用使系统产生周期振荡,并在异质性环境中产生稳定的螺旋波,破碎的螺旋波和环形波三种分布模式;(11)集合种群与资源含量的空间分布因为相滞而互补;(12)具有生态位构建的集合种群续存不仅取决于侵占率与灭绝率之间的平衡,而且依赖于生态位构建能力同其生境的自然消耗速率之间的妥协;(13)当生境中适合侵占的斑块比例小于其侵占率与灭绝率之比时,生态位构建作用促使集合种群在一定条件下续存:(14)生境斑块的状态从不适合到适合转变过程中存在生态位构建强度和系统初始条件这两个阈值;(15)集合种群的大小同正生态位构建能力正相关,意味着对环境具有较强正作用的有机体对维持有效生境起积极作用。

First, select four kinds of main risks source from bigly celebrate the main risk in region source, namely the flood, drought, sand-dust weather and petroleum pollution accident, etc. According to the different a request for to habitat, study this 19 kinds of landscapes ecosystem type of the Regional induce for 7 kinds of ecosystems system: Then the marsh of bulrush, lakes and reservoirs , salt alkali wasteland, prairie, island form wood, farmland, town. The difference is proceeded by characteristic according to each type ecosystem to the analysis of four kinds of main risks source, including the certain risk all rate, delimiting the space distribute, analyzing the risk strength to the receptor etc. At proceed the revelation the different from endanger to analyze the inside, this text borrows ecosystem index number that this index sign to reflect primarily habitat the ecosystem meaning of the type of habitat the different from position, with weak an index number to show the destructibility of the habitat, from but compute each ecosystem that is lost by ecosystem system an index number.

首先,从大庆地区主要的风险源中遴选出四种主要的风险源,即洪涝、干旱、沙尘天气和石油污染等;依据不同生物类群对生境的要求,将本研究区域的19种景观生态类型归纳为7种生态系统:即芦苇沼泽、湖泡库渠、盐碱荒地、草甸草原、岛状林、农田、城镇;对四种主要风险源的进行分析,包括确定风险概率,划定空间分布,对风险受体的作用强度分析等;在进行暴露和危害分析中,本文主要借生态指数这一指标来反映不同生境类型的生态意义和地位,以脆弱度指数来体现不同生境的易损性,从而计算出各受体生态系统的生态损失度指数;由于各主要风险物质对风险受体的作用强度是不同的,对形成区域性生态风险的作用大小也有差异,因此本文采用层次分析法对主要生态风险物质进行综合评价,并把判断矩阵排序权值的合理计算问题归为—非线性化问题,并提出用基于遗传算法(GA[5])的层次分析模型进行权重分析;进行风险表征,即综合前面两个阶段的信息,对环境中风险的性质和强度以及风险评价过程中不确定性问题进行分析与描述,并划分出五级生态风险区;最后,根据划分的五级生态风险区的特征,分别提出针对各生态风险区的生态风险管理对策。

Based on the eco- environment function, confirmed the constitution of eco- environment water demand(including the inside of the watercourse.and the ecological water demand of the outside of the watercourse such as ecological water demand of economical crop, of lake or reservoir and of cities.).③Analyzing the physical geography, hydrography, economy characteristic and water resource status, getting the proper calculation method. The Tennant applied to the eco- environment water demand of inside of the watercourse, woodland minmum eco- environment water demand calculation method applied to the eco- environment water demand of woodland, water ration method applied to farmland the eco- environment water demand, water evaporation method applied to the reservoir eco- environment water demand.

本文以流域生态环境需水为主要研究对象,因此重点阐述了流域生态环境需水量的分类和计算方法;②通过分析流域生态系统构成与流域生态环境功能,并分时段和河段考虑,确定了桃花江流域生态环境需水量的组成,即包括维持现状河道生态环境功能现状的现状生态环境需水量与流域生态环境改善的生态环境需水量,前者包括河道内生态环境需水量(维持河道基本生态功能需水量、维持河道自净稀释功能需水量、补充地下水水量及美化流域景观娱乐需水)与河道外生态环境需水量(流域内植被、森林、农田的需水量和与河道相连的池塘、水库等的需水量);后者还包括为治理改善流域生态环境而拟规划林业生态建设所需水量;③对桃花江流域的自然地理、水文地质和社会经济特征以及水资源现状及其主要生态环境问题进行了综合分析,提出了适合桃花江流域的生态环境需水量计算方法,即采用Tennant法计算河道内生态环境需水量,采用林地最小生态环境需水量法计算林地生态环境需水量,采用需水定额法计算农田生态环境需水量,采用水面蒸发法计算水库、池塘生态环境需水量。

Based on the analysis of the basic eco-environmental characteristics of Liaoning Province,and by means of remote sensing,Geological Information System software,and comprehensive analysis methods,this paper made an ecological zoning of this province on three levels,namely,ecological zone,ecological subzone,and ecological function zone.

分析了辽宁省生态环境基本特征,根据生态功能分区的原则与方法,应用遥感、地理信息系统和综合分析等手段对辽宁省在生态区、生态亚区和生态功能区3个级别上进行生态分区,划分为4个生态区、21个生态亚区和52个生态功能区。

In this thesis, the digitization, informationization, modelization and videotex of research on ecological environment security were achieved by using RS-GIS-EIS integrated technology.

论文的创新和特色在于,首次提出土地生态环境安全的概念,将生态安全研究的理论与方法引入土地生态环境安全研究中,并在这些理论和方法的指导下进行了吉林西部土地生态环境安全的研究;首次在吉林西部地区进行了土地生态环境敏感性评价,从土壤退化和土地盐碱化敏感性评价反映了吉林西部土地生态环境不安全的潜在危机;构建了土地生态环境安全评价的压力-状态-响应指标体系,该体系既体现了指标总体上的因果关系,又渗透了生态环境与经济的可持续发展;在土地生态环境安全评价过程中,本文提出用栅格点状评价单元和行政区面状评价单元结合的方法进行土地生态环境安全评价,使评价结果和分区更加精确;首次进行生态安全预警的研究。

Although many scholars had attempted to define it, the typical definitions of niche are Grinnell's space niche, Elton's functional niche and Hutchinson's hypervolume niche; Niche metrics include niche breadth, niche overlapping, niche volume and niche dimension, among which niche breadth and niche overlapping are two important indexes that can be used to characterize a species niche and the relationships between species niches.

许多学者都试图给生态位下定义,但最具代表性的当推Grinnell、Elton和Hutchinson分别给出的&空间生态位&、&功能生态位&和&多维超体积生态位&定义;生态位测度包括生态位宽度、生态位重叠、生态位体积及生态位维数等,其中生态位宽度和生态位重叠是描述一个物种的生态位以及物种生态位间关系的重要指标。

It showed that the niche breadth and niche overlapping indexes of the enclosed grassland in 2007 are much lower than in 2006 as a whole; The niche breadth of Artemisia ordosica is bigger than other species in the region in 2002. In 2003, the dominant species were Artemisia ordosica and Salsola ruthenica. Their niche breadth indexes were 0.544 and 0.460 respectively. The results of niche overlapping in 2006 and 2007 also showed that the species with big niche breadth didn't always have big niche overlapping, and the niche breadth and niche overlapping did not have a positive direct linear relation.

结果表明:2007年封育区植物种的生态位宽度及种间的生态位重叠指数总体上较2006年有所降低;2006年黑沙蒿生态位宽度最大,达0.768,是06年封育区的优势种;2007年封育区的优势种为刺沙蓬和黑沙蒿,其生态位宽度值分别为0.544、0.460;2006年和2007的生态位重叠结果均表明,生态位宽度大的物种不一定和其他物种有大的重叠指数,较高的生态位宽度和较高的生态位重叠之间并不存在直接的线性关系;2006年、2007年较高的Pianka生态位重叠指数都出现在生态位宽度较小的物种之间。

Then current status of considering ecoenvironmental water demand in planning and related planning is presented in details. Based on that the importance and urgence of introducing eco-environmental water demand in eco-environmental construction planning are as follows.(1) Collocating enough eco-environmental water demand is the key to eco-environmental construction planning;(2)introducing eco-environmental water demand presents new ideas and measures for water resource management, which promotes planning;(3) sound eco-environmental water demand is the subject of eco-environmental construction planning;(4) the objects of planning, on the contrary, improve the research of eco-environmental water demand.

接着对现在的生态环境需水在生态环境建设规划及相关规划中的应用情况作了详细介绍,在前面的基础上提出在生态环境建设规划中引人生态环境需水的重要性和紧迫性:(1)配置足够的生态环境需水是生态环境建设顺利进行的关键所在;(2)引入生态环境需水为水资源管理提供新思想、新途径,促进生态环境建设规划的实施;(3)合理的生态环境需水是生态环境建设规划的实现目标;(4)生态环境建设设定目标反过来又促进生态环境需水的研究。

On the basis of the metioned above, in the mass, the thesis amalyzes the ecological problems that Wuzhong has and the reasons that result then in , ecological construction acheivments and it"s consumable affecs ;then in detail and using the way combined fix quatity with quality , analyzes the condition, degree, mechanism, processof ecological caustic of various regions and kinds of ecological systems in Wuzzhong, juging the feasibility of restore and reconstruction of them. The paper indicates, as a whole ,the degree of eological caustic of the region is relative severity, but the diffefences between the plain region and the mountains region are very obvious, and all of them can be retored and rconstructed, wich has been proved by theory and practices. According to the conclutions and combining them with the mature theory ecological fumction dividings and the condition of Wuzhong"s mature and society , the study divides the region into seven ecological functional areas. On basis of the ecological construction strategic targets presented by the governments of the country and Ningxia,Wuzhong and the caustic condions of different ecological system in defferent areas, the author design the models of ecological restoration and reconstruction for the different ecological areas and how to use them.

在此基础上,从宏观上分析了吴忠目前存在的主要生态问题和形成原因、生态建设成就与成果自耗因素,接着着重从微观上对吴忠各地的生态致损情况、各类生态系统的受损度、受损机理和过程、生态恢复与重建的可行性进行定量和定性分析判断,指出从整体上看该区域生态受损比较严重,但存在着明显的山川二元结构,其恢复与重建在理论和实践上均证明是可行的,并据此结合已成熟的区域生态功能区区划理论,以吴忠的自然、社会条件和其它有关区划结果等为依据,对吴忠整体进行了生态功能区区划,然后根据国家、宁夏与吴忠三级政府出台的各级别生态建设战略目标、任务,按照有关生态恢复学等有关理论,详细地对七大生态功能区中各受损生态系统的恢复与重建模式进行研究,提出了不同的生物与工程模式及实施办法、途径、措施。

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