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1.
In the 1:50,000 mineral-resource assessments for regions of different rock types, the application of universal kriging to process geochemical prospecting data, obtained from different sampling media, can provide much useful information for evaluating mineralization potential. The method has succeeded in effectively separating local anomalies from the regional background, objectively extracting useful information, and improving the analysis of the metallogenic and ore-controlling factors, thereby playing an important role in qualitative and quantitative predictions. In 1:50,000 mineral-resource assessment it is advantageous to use universal kriging in the processing of geochemical prospecting data because universal kriging has many advantages compared to other oreassessment methods.  相似文献   

2.
在全面了解国内外有关生态安全研究现状的基础上,运用层次分析法和专家咨询等方法,构建了塔里木河流域生态安全评价指标体系并确定了指标权重,比较分析了塔里木河流域不同区段生态安全状况。结果表明,从20世纪60年代到21世纪,流域生态安全水平呈逐渐增高趋势,水资源、土壤、植被对流域生态安全贡献最大,气象对生态安全贡献较小,人类活动对下游生态安全影响较强,社会经济发展水平几乎没有贡献。对塔里木河流域生态安全进行评价,可为流域生态综合治理提供科学依据。  相似文献   

3.
岩溶地区旅游生态安全评价及趋势分析——以广西为例   总被引:1,自引:1,他引:0  
张鹏  丘萍 《中国岩溶》2014,33(4):483-489
岩溶地区拥有丰富的旅游资源,但是生态环境相对脆弱,根据岩溶地区旅游发展的特点,以"压力-状态-响应"(PSR)模型为基础,同时从生态安全的概念出发,涵盖生态风险、生态健康和生态足迹指标,建立了岩溶地区旅游生态安全评价指标体系。调整的主要指标包括:土地压力指标、旅游经济密度、年平均气温和年平均降雨量指标、旅游空间密度、游客密度指数、旅游收入指标等。采用综合指数法和熵权法,分别引入2012年和2007年两年的数据,对广西岩溶地区旅游生态安全的现状、发展趋势及变化趋势的内在原因进行了分析。实证结果表明:(1)从现状评价看,2007、2012年广西岩溶地区旅游生态安全水平总体较低,处于安全级别的城市主要位于广西中部区域,其他城市则处于不安全级别;(2)从影响指标看,经济状态和旅游生态状态对当地的旅游生态安全影响较大;(3)从变化趋势看,广西岩溶地区旅游生态安全状态逐渐好转,广西中部地区保持安全状态,紧邻广西中部地区的地市处于持续危险区域,但综合指数呈上升趋势;梧州和贵港两个位于广西东部的城市同样处于持续危险区域,但是旅游生态安全综合指数呈小幅下降趋势;(4)旅游生态安全状态和趋势与岩溶分布没有显著的相关关系。   相似文献   

4.
A set of theories and methods has long been needed to enhance geological prospecting. Since 1982, we have been predicting mineral-resource potential based on geological research in China, using a comprehensive information theory and method (CIM), developed to identify mineral-resource domains. The key features of CIM are: (1) to establih comprehensive prospecting models on various scales on the basis of a metallogenic model; the prospecting models are statistical in nature and incorporate a range of ore indicators, (2) to compile detailed metallogenic maps that reflect metallogenic regularities, ore-controlling factors, prospecting indicators, and the positions of favorable target areas, and (3) to establish statistical prediction models of undiscovered mineral resources. This CIM method has been effective and has provided significant economic benefits in the past few years in China.  相似文献   

5.
流域生态系统健康评价研究进展   总被引:1,自引:0,他引:1  
于璐璐  朱丽东  吴涛  赵鑫  陈瑞  郦坷飞 《水文》2017,37(3):7-13
流域生态系统评价体系是评价研究流域是否健康的基本依据,其评价结果为流域生态系统保护措施和政策制定提供基础。在介绍流域生态系统健康状态的前提下,总结了国内外流域生态系统评价理论和评价指标的发展历史及现状,整合出目前较为流行的评价体系,并着重阐述了五类实用模型,分别为:水基系统评价模型、改进物元分析、生物完整性指数法、压力-状态-响应模型(PSR)及景观格局分析法。针对不同的流域环境选择合适的评价体系是准确评价流域生态系统健康状况的根本。总结得到综合指标评价体系,主要包括物理、生物、社会环境、生态功能及社会功能等五种指标,在明确指标后按评价流程对流域进行系统评价。对现存的问题进行了分析与展望。  相似文献   

6.
The ecological security status of Pingtan Island (PI) from 2005 to 2011 is evaluated dynamically. Results show that the ecological status of PI is increasing, and the quality of its environment is constantly optimized, especially during 2009–2012. Principal component analysis is used to analyze the driving forces of the ecological security of PI. The driving force, status, and response of PI determine its ecological security. The effect was evident in 2011. The trend of principal component synthetic score is consistent with that of the ecological security dynamic map of PI. This study can enrich the empirical case and the relevant theoretical system of environment assessment in the island. Meanwhile, it can provide reference for the evaluation methods of ecological security status of the same kind of islands at home and abroad as well as the optimal control policies.  相似文献   

7.
In recent decades, due to the combined effect of human activities and climate change, the ecosystem of our country has been continuously degraded, seriously affecting the sustainable economic and social development. In order to protect and recover the ecosystem, China has invested heavily in launching a series of key ecological programs and projects including North Shelter Forest Program, Grain for Green Project and integrated ecosystem management of rock desertification. How to comprehensively and timely grasp the ecological effects and existing flaws of the implementation of key ecological projects so as to scroll the implementation of ecological projects and ensure the implementation effect of the projects, and promote the follow-up ecological engineering deployment of being scientific and space-oriented is a major imperative for the country. Therefore, the National Key Research and Development Program of China set up the project of “Monitoring and Assessment of Ecological Benefits of Key Ecological Engineering in China”. Through the implementation of this project, we will establish an indicator system for monitoring and evaluating the ecological benefits of key ecological projects, developing various technical systems for monitoring and evaluating the ecological benefits of key ecological projects, quantitatively evaluating the ecological benefits of key ecological projects, and concise the technical approaches to enhancing ecological benefits. We will provide a scientific basis for future planning and management of key ecological projects.  相似文献   

8.
基于DPSIR-TOPSIS模型的湖南省土地生态安全评价   总被引:5,自引:0,他引:5  
徐美  朱翔  李静芝 《冰川冻土》2012,34(5):1265-1272
基于DPSIR模型, 从驱动力、 压力、 状态、 影响、 响应五方面构建湖南省土地生态安全评价指标体系, 运用基于熵权的改进的TOPSIS法对2001-2010年湖南省的土地生态安全状况进行评价. 结果表明: 人均GDP、 GDP增长率、 单位耕地面积农药施用量、 单位耕地面积地膜使用量、 土地利用率、 耕地旱涝保收率、 单位耕地粮食产量、 单位建设用地, 二三产业增加值、 农民人均纯收入、 经济密度、 环保治理投资占GDP比重等指标是影响湖南省土地生态安全的主要因素; 湖南省土地生态安全状况整体呈上升趋势, 由不安全状态提升到较不安全状态, 但距安全状态仍有较大差距; 从各子系统看, 湖南土地生态安全的驱动力、 影响和响应系统的安全状况均呈逐步上升趋势, 状态系统也逐步波动上升, 但压力系统的安全状况呈逐年下降趋势.  相似文献   

9.
Upstream inflow decline and excessive water withdrawal are the major reasons for failure in maintaining ecological functions of wetlands and could lead to wetland drought and degradation. Quantitative evaluation of wetlands drought constitutes the basis for managing and scheduling water resources and guaranteeing biological safety. In the study, we proposed a Palmer wetland drought index (PWDI) based on the water balance model that describes wetland hydrological characteristics linked to its located basin to describe drought-reflected ecological characteristics in lacustrine Baiyangdian Wetland and compared it with Palmer drought severity index (PDSI). The results presented that PWDI is able to reflect the worst drought in history, and the drought is mainly affected by water stored in the wetland, but PDSI is inadequate for evaluating the wetland drought. The PWDI methodology provides a clear, objective approach for describing the intensity of drought and can be readily adapted to characterize drought on an operational basis.  相似文献   

10.
湖南土地资源可持续利用的生态安全评价   总被引:41,自引:0,他引:41  
生态安全是土地可持续利用的基础,土地生态安全评价是土地可持续利用研究的前沿课题。以湖南省14个地州市为样本,从1999年社会经济和土地生态环境压力、土地生态环境质量、土地生态环境保护和整治能力等方面的运行数据中选取人口密度、城镇化水平、人均耕地等24个指标,采用均方差客观赋权,从各指标的统计特征值及全国的平均值出发,确定本省的生态安全评价阈值S,计算各地市多指标加权综合评价值,试图对本省土地生态安全进行客观综合评价。  相似文献   

11.
结合对干旱区生态安全和生态需水量关键科学问题的探讨,提出干旱内陆河流域生态脆弱区的生态安全分析是以水过程研究为核心的,水文过程控制着生态过程,对流域生态系统的稳定性有着直接影响,而水资源开发利用和水循环对生态系统功能有重要影响,天然植物恢复和生长的合理地下水位的研究是确立生态需水量的基础.并实证分析和计算了维系塔里木河生态安全的生态需水量,塔里木河干流现状生态需水量为31.74×108 m3,其中,上、中、下游分别为9.95×108 m3、18.47×108 m3和3.32×108 m3.  相似文献   

12.
基于景观生态学理论,借助多时相遥感数据与GIS空间分析技术,运用“压力-状态-响应(press-state-response,PSR)”模型,构建岩溶地区城市景观生态安全评价体系,通过空间叠加分析得到2000年和2013年贵阳市城市生态安全等级分布图,并就其空间分布规律与演化特征进行了对比分析,结果表明:2000年、2013年贵阳市城市生态安全指数均较低,2000年处于安全级别以上的值为3.04,2013年处于安全级别以上的值下降到1.78,在空间分布上呈西南向东北递增的趋势;在2000-2013年间,景观生态安全指数除湿地以外其他景观类型均呈现明显的下降趋势,其中农田恶化较为明显,湿地是唯一改善的景观类型。研究时段内贵阳市景观生态安全状况处于恶化趋势,因而建议在今后的城市规划与建设中应优化土地利用格局,以提高城市景观生态安全水平。   相似文献   

13.
Ecological security evaluation is an important way to identify the need for improvement in a watershed and to assess the degree of regional sustainable development. Using a driver–pressure–state–exposure–response model, a comprehensive system of ecological security indicators was developed, and it was demonstrated in a case study of the main ecological problems facing the Qinghai Lake Basin. Indicators of the status of the natural ecological environment, socioeconomic pressure, and the degree of environmental damage were chosen to develop the model, and comprehensively evaluated the basin’s ecological security in 2000, 2004, 2009, and 2013 to reveal changes in the ecological security in response to changing climate and land use. The overall ecological security of the basin improved from 2000 to 2013, with considerable restoration and reconstruction of the ecosystem. From 2000 to 2004, environmental deterioration increased slightly as a result of pollution caused by human activities, excess land reclamation for agriculture, land desertification, and grassland degeneration. However, the obvious effect of ecological protection policies, such as conversion of farmland into grassland and stall feeding of livestock instead of grazing, led to improvement of the ecological environment from 2004 to 2013. Ecological security in the basin increased with increasing precipitation during the study period.  相似文献   

14.
基于多种水文学法分析大汶河干流生态基流   总被引:4,自引:0,他引:4       下载免费PDF全文
侯世文 《水文》2015,35(6):61-66
分析估算大汶河干流生态基流量是解决其生态环境恶化问题的基础。根据大汶口水文站历年径流资料,采用Tennant法、基流比例法等多种水文学法推求生态基流值,通过计算不同水平年的年际、年内不同水期和鱼类产卵育幼期生态基流量,在分析了各种方法应用区间和适用条件的基础上,综合考虑拦蓄引水工程和河道生态基流缺失等因素确定了大汶河干流生态基流。认为:基流量为1.1~14.1m~3·s~(-1)能更好地代表该区域不同水期的河道生态需水,经分析其生态基流保障程度基本达到90%以上,说明本文采取的方法在计算代表北方季节性、雨洪型河流的生态基流时是合理、可行性的,并进一步提出了生态基流的保障措施。  相似文献   

15.
Research on the “source–sink” landscape pattern of nonpoint source pollution is of great significance to natural resource management, environmental protection, water quality improvement, nonpoint source pollution prevention and control, and ecological security pattern construction. Remote sensing has proven by many scholars as a practical and effective technique to study landscape patterns and nonpoint source pollution. However, there are still many obstacles to the application of remote sensing technology, such as classification errors, scale effects and the issue, whereby landscape metrics cannot describe the landscape information comprehensively. In view of the characteristics of the macroscale and multi-scale of remote sensing, the analysis of landscape patterns is the basis for the study of the relationship research between patterns and ecological processes, and it is also the key to the study of landscape dynamics and functions. This paper attempts to summarize the representative results and the challenges of remote sensing in the study of the source and sink landscape of the nonpoint source pollution landscape and provide corresponding solutions as a reference for future research.  相似文献   

16.
干旱区内陆河流域的生态安全与生态需水量研究   总被引:2,自引:0,他引:2  
结合对干旱区生态安全和生态需水量关键科学问题的探讨,提出干旱内陆河流域生态脆弱区的生态安全分析是以水过程研究为核心的,水文过程控制着生态过程,对流域生态系统的稳定性有着直接影响,而水资源开发利用和水循环对生态系统功能有重要影响,天然植物恢复和生长的合理地下水位的研究是确立生态需水量的基础。并实证分析和计算了维系塔里木河生态安全的生态需水量,塔里木河干流现状生态需水量为31.74×108 m3,其中,上、中、下游分别为9.95×108m3、18.47×108m3和3.32×108m3。  相似文献   

17.
针对平原区多目标地球化学调查工作中亟待解决的技术问题,在试验研究资料基础上,本文提出了平原区多目标地球化学调查异常查证及生态效应评价方法。异常查证阶段,首先应用相关关系法确定异常组分的地球化学基准值,而后进行异常分类,确定异常的成因和形成机理,为异常生态效应评价提供理论基础。在异常生态效应评价中,首先要弄清土壤中异常组分全量与其活性组分间的关系,进而探讨土壤和农作物中异常组分的含量关系,最终依据相关标准,评估农作物中重金属元素的含量水平,及其通过食物链对人体健康可能造成的危害。  相似文献   

18.
国家安全是国家生存与发展的基本前提, 是维护国家利益的最根本保障。水安全是国家安全的重要组成部分, 既要保障国家经济社会可持续发展, 又要支撑国家粮食安全、能源安全以及生态安全等。水安全历来是治国安邦的大事, 研究国家水安全问题具有重要意义。本文在分析国家安全需求及水安全研究成果的基础上, 提出在"国家安全学"一级学科框架下设立"国家水安全学"二级学科(或分支学科)的思路, 界定国家水安全学的概念和学科定位; 提出国家水安全学的学科体系框架, 包括研究对象、理论体系、方法论及应用实践; 最后, 考虑学科发展需求, 对国家水安全学的未来发展进行了展望, 可为进一步完善和发展国家水安全学提供借鉴。  相似文献   

19.
阿尔金山东端北部区域生态环境修复模式研究   总被引:1,自引:0,他引:1  
阿尔金山荒漠化防治生态功能区是甘肃西部、新疆乃至整个西北地区重要生态屏障,对阿尔金山东端北部区域为代表的西土沟流域生态环境现状和存在主要问题进行分析,提出区域生态环境治理构想和因势治洪-以洪治沙-自然净化-综合利用的区域洪水资源开发利用模式和以“水害”治“沙害”、变害为利的区域生态环境、沙漠治理模式。国内外学者对本区域荒漠化防治、草地生态安全评价有部分研究,但对沙漠区洪水资源开发利用问题研究比较罕见,在沙漠地区洪水资源化利用方面具有很强的代表性,为阿尔金山保护区的规范管理和可持续对策制定提供科学依据,对同类地区生态环境修复提供示范。  相似文献   

20.
本文以DSR模型为框架建立了湖南洛塔屋檐洞水库生态安全评价指标体系,并引入缀块丰富度密度、聚集度、景观均匀性指数等景观生态学指数,采用层次分析和模糊评判有机结合的综合方法,从生态安全状态、压力、响应三个指标体系角度出发,具体分析了屋檐洞库区自然、社会、经济三方面的生态安全问题,对库区生态安全进行综合评价,评判出屋檐洞水库库区系统生态安全属于安全级别,并根据评价中间结果找出生态安全响应是洛塔中寨水电站建设的潜在生态危险因素,提出建立合理科学的生态补偿机制以及库区生态安全预警系统等对策.  相似文献   

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