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1.
本文旨在对若尔盖湿地退化、草原沙漠化的驱动因素进行分析。找出导致湿地退化、草原沙漠化的主导因素,并寻求合理对策。在前人已有研究和野外实地考察的基础上。对获得的数据资料进行对比分析,分析结果显示近几十年来若尔盖地区人口激增、挖沟排水、过度放牧等人为因素对湿地退化、草原沙漠化的影响明显.而气温升高、降雨减少等自然因素影响较弱。分析表明.若尔盖湿地沙漠化在于人类活动干扰和自然因素的双重作用。自然因素是湿地沙漠化发生的大环境,是大空间、大跨度造成湿地沙漠化的自然环境背景.为生态环境恶化、湿地沙漠化提供一种可能性;而近几十年来人类强烈的破坏性活动才是该地区生态环境恶化、湿地沙漠化的主导因素。在遵循自然客观规律的基础上.有针对性地制定切实有效的保护和恢复措施很有必要。  相似文献   

2.
人类活动对松嫩平原生态环境的影响   总被引:9,自引:0,他引:9  
探讨人类活动对松嫩平原的影响 ,有助于了解生态环境退化的过程与机制 ,对于退化生态环境的改善意义重大。本文在分析松嫩平原生态环境的脆弱性、人类活动史、人类的活动方式及人类活动对生态环境影响的基础上 ,指出人类活动干扰并破坏了生态环境的缓冲因子 ,使退化因子的作用因失去缓冲因子的制衡而加强 ,引起土地沙化和盐渍化。文章还论述了生态环境的脆弱性、外部干扰和生态环境退化之间的关系以及松嫩平原生态环境的演化机制 ,从而引导人类遵从自然规律  相似文献   

3.
陕北风沙区生态环境退化已成为区域可持续发展的主要威胁。在检林地区生态功能演化的过程中,强烈的人文过程在潜在的自然因素基础上对生态环境退化发挥了显著作用,区域文化在生态退化过程中产生了重要的内在影响。通过对区域文化在榆林地区景观生态历史演变与景观生态建设中的影响分析,认为区域人文环境建设是遏制榆林地区生态环境退化的关键途径之一,景观生态文化建设是区域文化响应的重要方式,其重点内容包括:①树立正确的景观生态建设观。景观生态建设不仅仅局限于某个生态系统,而且还注重于景观格局及其各要素间的功能联系,合理的景观管理措施可以使生太系统恢复到以前或与之相近的状态;②普及生态科学,消除知识贫困,强化“居安思危”的社会心理;③完善景观生态建设的政策与制度;④建立景观生态建设产业体系,促进形成新的生产方式与经济行为模式。  相似文献   

4.
岷江上游地区在我国长江上游同山峡谷区代表性,由于近几十年来人为活动加剧,该区生态系统严重退化。简要介绍了岷上游山地生态系统的概况,讨论了关键种群在退化生态系统研究中的作用和意义。在此基础上进一步认为,岷江上游山地系统退化机理研究应以典型的干旱河谷灌丛,亚高山森林和亚高山草甸等主要生态为对象,以关键种群为核心和切入点,重点研究了干旱河谷批示植物种群动态有其与环境退化的关系、主要动植物种群在变化在草地生态系统退化过程中的作用、亚高山关键种苗木定居及对退化产生理生态适应机制、土壤微生物区系变化有其对系统中氮素归还的影响等,进而有助于在理论上阐述关键种群的生态功能,探讨关键种群变化导致生态系统退化的作用机理;在实践上为目前国家实施西部大开发生态环境建设的重大需求提供理论依据,推动恢复生态学的发展和该区域的生态建设。  相似文献   

5.
区域资源与生态环境综合监测及评价指标体系初探   总被引:6,自引:0,他引:6  
在综合分析国内外研究的基础上,提出了不同区域的基于“3S”技术的区域资源与生态环境综合监测及评价指标体系的初步框架。具体包括土地利用/土地覆被变化监测指标体系、生态环境退化监测与评价指标体系和区域生态环境建设实施状况监测指标体系。将监测与评价指标应用于规划和政策制定,以期为土地利用规划和生态环境保护规划的制定和评估规划的实施效果服务。  相似文献   

6.
湖南省农业生态安全与可持续发展初探   总被引:19,自引:0,他引:19  
农业生态环境是农业发展的前提基础,它的健康安全是农业可持续发展的关键。湖南省是全国的农业大省,但目前农业生态环境面临着土地资源退化、水土流失加剧、农业污染严重、农业自然灾害频繁、生态环境脆弱和耕地质量下降等一系列问题,对该省农村经济的发展和农业的可持续发展,造成了严重的影响,制约了农业发展的前景与潜力。在分析这些问题的基础上,探讨其产生的机理,并提出保护和建设农业生态环境安全的对策与建议,为实现该省农业可持续发展提供参考依据。  相似文献   

7.
我国西南喀斯特地区是世界上著名的脆弱生态区,土地退化严重,人地矛盾尖锐,区域发展可持续性差。对此区退化土地进行生态重建,是西部开发中十分紧迫的任务,本文以位于贵州喀斯特高原峡谷地带的关岭县为研究区,分析了喀斯特地区生态环境脆弱性的主要特点,土地退化的主要过程及生态,经济和社会系统驱动机制。在此基础上提出相应的生态重建对策,指出我国西南喀斯特地区可持续发展迫切需要外部的物质、技术,资金等投入扶持,而最终实现则需要立足于本地的生态重建和生态产业的良性发展。  相似文献   

8.
本文在简单回顾与述评有关定量研究人口在生态环境中作用程度所采用的方法的基础上,认为无论是通常采用的统计学模型或是其他固定函数模型等,都有较大的弊端。而用系统动力学方法来研究这类问题,具有较好的优势与可行性。为此,本文以新疆塔里木河流域为例,建立了该流域人口变动与生态环境退化的系统动力学模型。在对模型进行有效性检验的基础上,演示了该流域近20年来源流段、上中游段和下游段各种不同人口变动条件下下游出现的各种生态环境后果,并与实际的生态环境现状进行对比,从而得出一系列有意义的结论。  相似文献   

9.
选择长江源区的格尔木市唐古拉山镇作为研究区,通过野外实地采样与室内测试分析相结合,在分析草地植被不同退化阶段和不同土层深度下土壤持水能力特征的基础上,探讨了草地植被退化对土壤持水能力影响。结果表明:(1)在相同草地植被退化阶段,毛管持水量、饱和含水量和田间持水量随土层深度变化的特征基本一致;在相同土层深度上,毛管持水量、饱和含水量和田间持水量随草地植被退化的特征也大体相同。(2)在相同草地植被退化阶段,土壤持水量总体上随土层深度增加而减少,特别是在未退化阶段,10~20 cm土层的毛管持水量、饱和含水量和田间持水量比0~10 cm土层分别减少了12.38%、33.73%和7.64%。(3)在相同土层深度上,土壤持水量总体上随草地植被退化而减少,特别是在0~10 cm土层,轻度退化阶段的毛管持水量、饱和含水量和田间持水量比未退化阶段分别减少了41.52%、59.95%和27.03%。(4)土壤持水量与土壤容重、总碳、有机质和总氮显著相关,它在草地植被不同退化阶段和不同土层深度下的变化可能与地表覆被状况、植物根系数量和分布特征所引起的土壤容重、有机质等变化有关。研究可深化对草地植被退化与土壤持水能力相互关系的理解和认识,并为长江源区生态环境和水资源状况研究提供参考依据。 关键词: 土壤持水能力;草地植被退化;长江源区;影响  相似文献   

10.
鄱阳湖水利枢纽工程与湿地生态保护   总被引:8,自引:0,他引:8  
鄱阳湖水利枢纽工程是鄱阳湖生态经济区规划中的重要内容,针对公众围绕枢纽工程对生态环境影响的质疑,通过对鄱阳湖湿地生态系统特征的分析,提出了鄱阳湖的生态保护目标与主要保护对象,论述了鄱阳湖近年来出现的水量不足、水质恶化、湿地退化、渔业资源萎缩等主要生态问题,介绍了目前鄱阳湖水利枢纽工程的构想,分析了枢纽工程可能产生的影响。在此基础上,提出了开展枢纽工程的科学论证与科学规划,进行生态系统设计,实行阶梯式水位、适应性生态调度和动态化科学管理的建议。  相似文献   

11.
大城市应对气候变化的可持续发展研究——以上海为例   总被引:1,自引:0,他引:1  
在全球气候变化背景下,社会城镇规划与自然气候变化之间的关系越发密切,城镇规划体系需要纳入气候变化的影响并考虑适应气候变化的策略。首先以发达国家及世界著名大城市为参考,对美国、德国和日本在应对气候变化的城镇可持续发展规划方面的成功经验和实践措施分别进行了综述和提炼;然后,以上海为例,对照分析了我国大城市在城镇化过程中面临的气候变化挑战及存在的脆弱性,包括城镇发展规划与气候环境的相容性考虑不够、城镇化过程对气候环境的影响缺乏充分论证、城镇基础设施抵御气象灾害的能力较低、气候变化对城镇人体健康的影响未给予高度关注等;最后,指出了我国大城市应对气候变化的城镇可持续发展思路及重点方向,即充分考虑区域气候容量、大力构建生态绿色通风廊道;深入开展城镇功能布局的气候可行性论证和气象灾害风险评估;加强城市气候变化研究和实验,不断更新城市规划设计参数和标准规范;加大对脆弱人群和外来常住人口生命安全和人体健康监测预警;积极完善城镇化适应气候变化的机制等,以期为城镇发展体系的编制和应用提供参考和借鉴。  相似文献   

12.
Since the reform and opening-up, the difference between the development of the west region and the other regions in China is increasing. In addition, the condition of the development of cities in west China needs amelioration. Developing conditions of the west provinces and its cities using economic barometers (e.g. gross domestic product (GDP) and per capita GDP) and urban population datum (e.g. urbanization level and city primary degree) have been analyzed in this article. Five indexes have been chosen to work on the development of the provinces, for example, the contribution degree of the increment in GDP, the contribution degree of the increment of per capita GDP, urbanization level, city primary degree, city primacy ratio. Conclusions are as follows. (1) The growth of the GDP and per capita GDP of the western provinces is in a poor way; moreover, it is not steady going. (2) The comparability among the characteristics of the urbanization level growth of the provinces is at a low level. (3) The urbanization levels of Inner Mongolia province and Sinkiang province are more-sensitive responders to the growth of per capita GDP, whereas those of Guangxi province and Tibet province are less-sensitive responders. (4) The urban population in most of the provinces are highly concentrated, which can be shown by city primary degrees and city primacy ratios. While working on these cities in west China, some earlier zone-organic cities are chosen as sample cities, and these cities are also analyzed using economic barometers and population datum. By analyzing the difference among the cities and comparing the research findings of Professor Zhou and the author, the following conclusions are made: (1) the growth of the GDP and per capita GDP of the cities are mostly not steady going; (2) the middle and big cities are more-sensitive responders to the growth of economy, whereas the small and mega cities are less-sensitive responders; (3) the sizes of southwest cities have a higher speed than those of northwest ones, and furthermore, the differences between them are still increasing.  相似文献   

13.
上海城区典型臭氧浓度偏低年的成因分析   总被引:2,自引:0,他引:2  
利用2006~2010年上海徐家汇、崇明、宝山、金山和浦东5个监测站的臭氧资料,分析了上海地区不同功能区臭氧的浓度特征及年际变化特征。结果表明:2006年上海地区臭氧平均浓度是这5 a的最低值,以徐家汇和浦东两个站臭氧浓度年际差异最为明显。2006年各站春末和夏季的臭氧浓度明显低于其他年份,而秋冬季臭氧浓度却差别不大。以徐家汇地区为例的综合分析表明,天气状况、日照时数、温度和风速等气象要素不是造成2006年上海城区臭氧浓度偏低的原因,臭氧前体物(VOCs和NOx)才是造成这种现象的主要原因。2006年4~8月NOx和VOCs浓度明显偏低,典型臭氧日变化情况下2006年VOCs/NOx比值较小,平均值为1.22,比2007、2008年低了近65%,而O3的生产率也分别减少了65%和59%。OZIPR模式的结果也表明较低的VOCs浓度以及VOCs/NOx比值,是导致2006年上海城区臭氧浓度偏低的主要原因  相似文献   

14.
Latin America comprehends notable variations in terms of natural environment, availability of natural resources, living standards, and demographic patterns. Latin America is a mosaic of cultures, post- and pre-Columbian. The rich variety of life forms discovered and described by chroniclers and traveling naturalists in the Neotropics contributed to the proposal, in mid-XVIIIth century, of a new system of classification and a scientific code of nomenclature for all organisms. Biodiversity was, for many centuries, a source of resources to be exploited in natura. In scientific circles, its inventory became the domain of taxonomists. But modern technology showed how important the miriad of life forms really are as sources of chemical molecules to be engineered as drugs and reassembled as novel manufactured products. We are on the brink of a new agricultural and medical revolution, thanks to the techniques of genetic engineering, which will lead eventually to the elimination of hunger and malnutrition.In this essay, the Brazilian environmental and social heterogeneity will serve as an example to illustrate some key points, which have influenced sustainability policies. The Amazon deforestation and indigenous knowledge (IK), subjects often associated with areas of high biodiversity, are usually the focus of environmental debates. The importance of IK in integrating development, reducing poverty and sustainability are considered together with the intellectual property rights of native populations.In the World Summit on Sustainable Development (WSSD) Implementation Plan, a few paragraphs were dedicated to Latin America, because of the pre-existing Action Platform on the Road to Johannesburg 2002, approved in Rio de Janeiro in October 2001. This paper calls attention to the need to draw up specific environmental policies for a region which shows an extremely high cultural and biological diversity, associated with a high availability of forests and water, among other resources.  相似文献   

15.
Sustainable development advocates for a balance between socio-economic development and the environment in the pursuit of human advancement. In Africa, high population growth and inadequate infrastructure in urban areas exert pressure on the environment and this threatens the health and wellbeing of urban residents. The population of the African continent until the 1960s was predominantly rural. This scenario has taken a swift turn and some of the major shifts in the global urbanisation process are taking place on the continent. Factors including natural increase in the population, rural–urban migration, strife and hunger leading to the internal displacement of populations have exacerbated the urbanisation process in Africa. The situation has been worsened by the imposition of Western development policies, including structural adjustment programmes on African nations, which has eroded the subsistence base of rural agricultural communities and further ignited rural urban migration. The failure of industry to absorb the increasing labour force has created massive unemployment and deepening poverty crisis in urban centres. Inadequate provision of infrastructure and services to meet the growth in urban populations has resulted in inefficient spatial development of urban centres, the proliferation of squatter settlements, inadequate basic amenities including potable water, sanitation and waste disposal. Poor environmental sanitation has resulted in the upsurge of infectious diseases and deteriorating urban health. Urban populations in Africa are also the worst affected by newly emerging diseases, particularly HIV/AIDS. The poor bear a disproportionately large share of the problems due to their particular vulnerability to environmental and health risks. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

16.
湿地生态系统服务功能评价模式的不足与改进   总被引:2,自引:0,他引:2  
本文基于对湿地生态系统服务功能评价研究发展历程的回顾,结合湿地资源保护面临的严峻形势以及社会经济发展对评价研究的现实要求,重点剖析了湿地生态系统服务功能的现状评价模式在研究定位、评价内容、评价方式和评价体系建设几个方面存在的主要不足,在此基础上提出相应的改进思路和方案.认为评价模式的改进应当以维持湿地生态系统健康和支撑区域社会经济可持续发展为研究目标,面向湿地生态系统管理方向补充评价内容,完善评价体系,强调人为活动干扰对湿地生态系统服务的影响及反馈分析,重视人类社会对服务功能需求的评价,并详细阐述干扰评价、需求评价和服务功能供需平衡分析的主要内容、方法和难点,总结湿地管理的意识和手段在服务功能评价各环节的体现.  相似文献   

17.
In despite of fluctuation in recent years, the grain yield in China has been increasing, which relieves the conflict between supply and demand and turns the situation of food security good. However, because of the rapid increase in food consumption, the conflicts of food quality and structure in the supply and demand equilibrium has become more and more obvious and the long-effective mechanism of food security has not been established yet. It is found that the factors affecting food security in China include the scarcity and dissipation of resources, farmers' low enthusiasm in planting grain crops and the inappropriateness of the emphasis and measures of macro-economic regulation and control. Therefore, the authors advance to optimize resources allocation, strengthen macro-economic regulation and control and policy stimulation and establish the mechanism of allocating grain production cost, to set up the long-effective mechanism of China food security and keep it stable in the long term.  相似文献   

18.
Two former uranium mines and a uranium reprocessing factory in the city of Aktau, Kazakhstan, may represent a risk of contaminating the surrounding areas by uranium and its daughter elements. One of the possible fingerprinting tools for studying the environmental contamination is using plant samples, collected in the surroundings of this city in 2007 and 2008. The distribution pattern of environmental pollution by uranium and thorium was evaluated by determining the thorium and uranium concentrations in plant samples (Artemisia austriaca) from the city of Aktau and comparing these results with those obtained for the same species of plants from an unpolluted area (town of Kurchatov). The determination of the uranium and thorium concentrations in different parts of A. austriaca plants collected from the analyzed areas demonstrated that the main contamination of the flora in areas surrounding the city of Aktau was due to dust transported by the wind from the uranium mines. The results obtained demonstrate that all the areas surrounding Aktau have a higher pollution level due to thorium and uranium than the control area (Kurchatov). A few “hot points” with high concentrations of uranium and thorium were found near the uranium reprocessing factory and the uranium mines.  相似文献   

19.
The formation of trophic structure has been studied in communities of amphibiotic insects (mayflies, stoneflies, caddis flies, and dipterans) and gammarids accounting for 90% of the total benthos biomass. The results show that the trophic groups prevailing by biomass in the metarithral subzone of small rivers are as follows: filtering collectors in rivers of the moderately cold-water type, collectors and scrapers in rivers of the cold-water type, and scraping predators and scrapers in rivers of the moderately warm-water type. Predators, scraping predators, and scrapers show seasonal changes in abundance and biomass. In the rithron of Far Eastern rivers, the abundance of predators regularly decreases in a south-north direction. The change of dominant groups along the longitudinal profile of the river is related to its zones and subzones. In the trophic structure of rivers exposed to anthropogenic impact, the number of trophic groups decreases and the remaining groups undergo changes in their qualitative composition and the ratio of their individual members.  相似文献   

20.
This article offers an analysis of the New Zealand eco-makeover program, WA$TED! It outlines how eco-makeover programs are an emerging sub-genre of the makeover phenomenon of lifestyle television where people and homes are subject to transformation by lifestyle experts, culminating in the revelation of the transformation at the end of the program. The article argues that the featured families in WA$TED! experience “everyday epiphanies” where they learn about their implication in existing environmental networks and they are ushered into new, more environmentally friendly networks. Drawing on actor-network theory, the article deconstructs the featured environmental networks, examining the roles of the program hosts, the transformations in the subjectivities of family members, and the functions of everyday household technologies and objects. The article argues that the significance of the program resides in the way the revelations make visible previously concealed linkages between families, everyday objects and practices, and the broader social and environmental domain.  相似文献   

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