103 research outputs found

    Research on remote sensing model for ecological water consumption and its application in Arid Areas

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    随着社会经济的发展,人类对水资源的开发利用量不断增加,致使对生态系统的干扰不断加大,甚至超出生态系统的承受能力,生态问题日渐突出,特别是干旱区流域水资源综合规划中要求突出人与自然的和谐,全过程贯彻科学发展观,在此过程中,合理确定生态耗水和需水起着至关重要的作用。然而,生态耗水概念不统一,没有公认的、普遍适用的方法,许多理论和方法还有待研究。本文在研究生态耗水理论的基础上,探讨生态耗水基本内涵,结合遥感、GIS技术和野外台站观测的技术手段,以多种分辨率的遥感数据和野外实验数据为信息源,选择哈密地区作为研究区,分析径流与人工生态系统的关系,确定生态耗水的量化途径、生态耗水的时空特性和逐级分类方法;通过遥感解译,获得该地区植被变化、土地利用、水域面积等资料;依据一定的实验或经验参数、公式,研究流域内不同类型区域土壤-植被-大气水分和能量传输过程,利用实验数据模拟计算土壤水分的时空关系,提取遥感数据中的土壤水分的分布信息;研制和建立流域遥感耗水模型,将遥感信息与水分平衡过程有机集成和计算,解决区域生态耗水中的关键技术问题,建立基于遥感的干旱区生态耗水信息系统,计算分区生态环境耗水量,解决哈密地区发展规划、水资源利用规划需要解决和回答的问题。本文主要完成以下工作:(1)分析生态耗水的基本理论,区分生态耗水、生态用水和生态需水的概念与利用方法,确定本文生态耗水的利用模式;(2)本文将在理论和实践两方面来研究流域的水循环过程和耗水机理,建立耗水分析方法和指标体系、技术规范,确定该流域耗水量的模型体系;(3)根据流域的特点按水资源利用计算单元,分别计算生态环境需水量,同时,划分出需要在水资源配置时考虑的生态环境需水量、以及不需要考虑的生态环境需水量;(4)通过一系列的模拟实验分析各种状态下遥感模型的尺度误差,分析植被结构和土壤湿度与遥感亚像元的关系,用MODIS、TM图像降低分辨率的方法检验实际的通量尺度误差;通过实际计算分析得出,在不同覆盖类型的交界处误差比较明显;根据尺度扩展的方法推导了遥感模型的参数尺度扩展公式,降低计算结果的误差。(5)通过分析研究区的常规观测数据,结合建立的遥感实验模型,建立了区域水资源的水量平衡方程;通过研究地表实际蒸散量与植被叶面指数、地表相对湿度以及地面温度之间的关系,在相关理论的基础上,建立了区域水资源实际蒸散的遥感模型,通过与水量平衡方程的联立,最后构建出区域水资源动态变化遥感定量测算模型,通过试验研究和模型分析,分析引水与耗水之间的相互作用关系,提出引水与耗水的动态关系曲线,通过土壤和地形数据来提取计算参数,并在研究区得到精度验证,其结果满足实际要求。(6)把遥感与地理信息系统技术引入到耗水计算模型中,建立适合于干旱区的遥感应用的技术标准和方法,以ARCGIS为平台,结合大型数据库和编程技术构建一套基于遥感与GIS技术的生态耗水信息系统。本文的研究将对无资料或少资料地区的水资源计算及其平衡分析提供技术支撑,特别为干旱区流域的生态耗水计算提供新的理论基础和方法。Exploitation and utilization of water resources are continuously increasing along with social and economic development, thus the disturbance to ecosystems is also increasing and even exceeds the carrying capacity of ecosystems, and the ecological problems become more and more serious. Especially, the harmony between human and nature is demanded in the comprehensive planning of water resources in the drainage basins in arid areas, and the scientific outlook on development is required to be implemented in the whole process, so it is crucial to rationally determine the ecological water consumption and demand in the process. However, the comprehensions to ecological water consumption are different, there are no recognized and universally-applicable methods, and a lot of theories and methods need to be researched advance. Based on researching the theories of ecological water consumption, some fundamental aspects of ecological water consumption are discussed in this paper. By applying RS and GIS technologies and field observation means and regarding multi-resolution RS data and field experimental data as information sources, a case study is carried out in aspects of analyzing the relations between runoff and artificial ecosystems and determining the quantification methods, spatiotemporal characteristics and step-by-step classification methods of ecological water consumption. In this paper, data of the changes in vegetation, land use and area of waters is derived from RS images’ interpretation. By researching the process of moisture and energy transferring among soil-vegetation-atmospheric in different regions in drainage basins based on certain experimental or empirical parameters and equations, the spatiotemporal relations of soil moisture content are simulated and calculated using experimental data, and the distribution information of soil moisture content is got extracted from RS data. A RS-based model of water consumption in drainage basins is developed, which integrated and calculated the RS information and the moisture balance process to resolve the essential technical issues of regional ecological water consumption, develop a RS-based information system of ecological water consumption in arid areas, calculate the values of ecological water consumption in all the subregions, and resolve the issues in the development planning and the water utilization planning in Hami Prefecture. The main working contents are mainly as following: 1)analyzing the basic theories of ecological water consumption, distinguishing the concepts of ecological water consumption, ecological water use and ecological water demand and the methods for application, and determining the applying mode of ecological water consumption in this study; 2)researching the hydrological cycle process and water consumption mechanism in drainage basins from both theoretical and practical sides, establishing a set of water consumption analysis methods, indices system and technical specifications, and then determining the model system of water consumption in drainage basins; 3) calculating the environment water demands of calculation units of water resources utilization separately referring to the local conditions in drainage basins, and identifying the environment water demand needed to or not needed to be considered in water resources redistribution; 4) analyzing the RS model’ s scale errors under various conditions in a series of simulation experiments and the relationships between vegetation structure, soil moisture content and RS sub-pixels,testing the actual flux scale errors by reducing the resolution of MODIS and TM images and getting a result from actual calculation and analysis reveals that errors are more obvious in the junctures of different cover types, and using scale extension method to deduce scale extended equations of the RS model’ s parameters so as to reduce the errors of calculated results; 5)establishing the equations of regional water resources balance based on analyzing the routine observation data of the study area and developed RS experimental models, researching the relations between actual surface evapotranspiration and leaf area index of vegetation, surface relative humidity and ground temperature and establishing of water resources based on correlative theories, and finally constructing a RS-based quantitative estimation model of the dynamic change of region water resources by joining the RS regional actual evapotranspiration model with the water balance equations; by experimental study and model analysis, analyzing the interaction between water diversion and water consumption, carrying out a dynamic curve of water diversion-water consumption, which gets parameters from soil and landform data and is validated its precision in the study area, with the results just satisfying the actual requirements; 6) introducing RS and GIS means into the calculation model of water consumption, establishing the technical standards and methods of water resources calculation in arid areas with the application of remote sensing technology, and constructing a set of RS- and GIS-based information system of ecological water consumption based on the large database and generic programming techniques on the platform of ARCGIS. This study can provide the technical supports to calculating and analyzing water resources and water balance in the areas where there are no or little hydrological data, especially can provide the new theoretical principles and methods for calculating ecological water consumption in the drainage basins in arid areas

    新疆且干布拉克超基性岩-碳酸岩杂岩体地质特征和地球化学研究

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    产有超大型蛭石-磷灰石矿床的且干布拉克超基性岩-碳酸岩杂岩体位于塔里木板块东北缘库鲁克塔格断隆南侧。世界上产超大型蛭石矿床的杂岩体中均发育有典型的碱性岩类,如霓霞岩、磷霞岩、霞石正长岩类,一般认为矿床的形成与该类岩浆作用有关。但是且干布拉克杂岩体不含典型的碱性岩类,矿床与富碱质超基性-碳酸岩浆有关,就成矿杂岩体的岩石类型而言,该矿床是不同于世界上其他地区的一个特殊类型。通过对该岩体不同岩相进行了地球化学和同位素年代学研究,获得岩体Sm-Nd等时线年龄为(802±52)Ma(95%可信度,MSWD=0.055 4),ε_(Nd)(t) =0.471,模式年龄T~(Nd)_(DM)为1208~1635 Ma,表明该杂岩体形成于新元古代

    干旱区景观格局空间过程变化的廊道效应——以塔里木河中下游河流廊道区域为例

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    采用缓冲带分析方法,河道两侧每距河道5 km划分一个垂直于河道的缓冲带(宽度10 km),计算每个缓冲带的景观格局指数,从景观水平和斑块水平上分析主要景观格局指数,以揭示河流廊道的辐射效应和特点.研究结果表明,研究区总体辐射宽度为30 km缓冲带,由于FG1区位于两河流域,其辐射宽度可达到50~70 km缓冲带,但中间有一个生态裂谷带.林地、湿地景观一般都集中分布于沿河两岸10 km缓冲带,而且距河越近,斑块密度越大,最大斑块指数也越大.在该区域的生态环境建设中,必须充分考虑其河流廊道的生态效应幅度,科学合理地规划和设计

    一种快速地形纹理生成和虚拟漫游方法

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    复杂场景的大范围、高分辨率纹理的快速漫游是虚拟现实、GIS、仿真等领域的关键技术与难点。DEM是对地形地貌的数字描述和模拟,利用DEM数据生成可视化地形,可以更好的描述特定区域的地形特征,通过对特定区域中模型的纹理生成和映射,配合光照、大气等区域内自然场景的建模技术,可生成较为逼真的真实场景。基于OpenGL编程进行DEM地形可视化是实现地形实时漫游的方法之一,利用层次细节模型降低场景复杂度以提高漫游帧速率是该类系统中的常用方法,由于场景复杂度问题,不同的系统在具体算法实现中采用的方法也不尽相同。本文以一个虚拟校园为例,针对DEM数据转换和LOD模型面临的问题,给出了特定场景的LOD模型数据处理思想和纹理快速纹理生成、匹配、映射算法。同时给出虚拟实时漫游中第一人称漫游和飞行漫游的一般方法,讨论了在Windows环境下使用OpenGL进行虚拟漫游的基本步骤。提出了一种新的根据场景特点快速生成和映射纹理途径。结果表明,该方法在保证真实感条件情况下达到了满意的实时漫游效果

    新疆水资源开发和优化配置研究

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    随着新疆工业和城市建设高速发展,人口和灌溉面积快速增长,水资源供需矛盾日益严重,水资源开发利用导致的生态环境问题日益突出。因此,深入思考和研究新疆水资源开发利用方略,制定科学合理水资源开发利用的优化配置战略,对于确保新疆经济社会可持续发展、生态环境良性循环有着十分现实的实践意义

    克拉玛依1957—2006年气温变化特征分析

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    分析克拉玛依1957—2006年逐年平均气温、平均最低气温、平均最高气温以及1月和7月的平均气温、平均最高气温、平均最低气温发现:克拉玛依近50a来平均气温、日最高、最低气温随时间呈增加态势,其中日最低气温增加较为明显,其结果导致日较差减少,日平均气温略为增加;20世纪80年代后年平均气温、日最高气温、日最低气温升高态势较为明显

    土地利用变化对绿洲区地下水硝酸盐空间变异特征的影响

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    应用遥感、地理信息系统和地统计学方法,分析了三工河流域绿洲区地下水硝酸盐空间变异特征和土地利用/土地覆被变化状况,探讨了土地利用变化对绿洲地下水硝酸盐空间变异特征的影响。研究数据主要包括2004年77口采样井地下水水质数据以及1987年TM影像和2004年ETM影像数据。结果表明,流域上游至下游硝酸盐含量逐渐降低,样点含量介于1.4~83.1mg·L-1之间,变异系数为1.11,属于较高的变异强度。上游冲洪积扇和下游冲积平原硝酸盐平均含量分别为27.37和6.02mg·L-1,冲洪积扇出现了显著的地下水硝酸盐污染。硝酸盐含量较高的区域均是土地资源开发历时较长的区域,主要为耕地和建设及工矿用地的土地利用变化方式。反映出随着绿洲的不断扩展,土地利用变化对地下水硝酸盐空间变异特征产生了显著的影响

    生态系统服务的价值评估方法研究

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    在综合分析国内外生态系统服务功能分类和估价研究基础上,对价值评估方法进行了汇总.目前对生态系统服务进行估价的方法可概括为4大类:实际市场评估技术、替代市场评估技术、模拟市场评估技术以及新近提出的空间-能值分析技术.由于生态系统服务本身的复杂性和交叉性,不同研究人员采用不同的研究方法得出的评价结果间对比性很低,缺少一个统一、规范、完善的评价体系来相互验证

    生态环境需水量在水资源规划中的配置方法

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    在剖析生态环境需水量概念和计算方法的基础上,把生态环境需水量分成需要在水资源规划中配置的水量和不需要配置的水量。在需要配置的生态环境需水量中,又分为直接配置水量和间接配置水量。在水资源规划中,既要计算直接配置水量,又要计算间接配置水量。文中介绍了需要配置的生态环境需水量的确定方法,并列举了在新疆哈密地区的应用实例
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