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1.
Given the importance placed on protected areas, determining their effectiveness in representing and maintaining biodiversity is a core issue in conservation biology. Nonetheless, frameworks identifying the breadth of issues associated with this effectiveness, and case studies of how well these are understood in particular regions, remain lacking. In this paper, we provide such a framework and an overview of the current state of knowledge of the ecological effectiveness of protected areas in the United Kingdom. Arguably, better data are available to address such issues in this region than anywhere else in the world. Nonetheless, studies remain scarce and have focussed foremost on the, rather narrow, issue of the effectiveness of management actions on individual sites in order to deliver fixed conservation objectives and discharge statutory responsibilities. Some attention has also been paid to how well the regional collection or portfolio of protected areas performs, particularly in capturing biodiversity features. Work on the extent to which protected areas in the United Kingdom form effective functional networks is in its infancy, but initiatives are under development. We identify some of the questions about the effectiveness of protected areas to which answers need to be known at the site, portfolio and network levels, and how significant progress might be achieved in addressing these.  相似文献   

2.
Questions concerning the value society places on the benefits and costs of control measures for acidic deposition cannot be fully achieved without considering the views held by the public-at-large. While numerous opinion polls have been conducted on acid rain, to date no systematic review of these data has been undertaken to identify underlying trends. This paper summarizes a comprehensive analysis of existing public opinion data in Canada and the U.S. from 1979 to the present, with particular attention given to identifying longitudinal trends, comparisons across jurisdictions, demographic group differences and comparisons with other issues. It is concluded that over the past five years, the North American public has become aware of acid rain as an environmental issue and, despite a limited understanding of the problem, believe it to be a serious one. Concern about acid rain has by now reached the level where most believe concrete actions must be taken, and a majority are willing to help pay for abatement programs. Canadians and residents of regions susceptible to acid rain damage have typically been more informed and concerned about acid rain, but such regional and national differences have diminished over time as the issue has become more widely recognized. These findings are discussed in terms of implications for policy and education strategies.  相似文献   

3.
酸雨对土壤呼吸的影响机制研究进展与展望   总被引:2,自引:0,他引:2  
刘自强  危晖  章家恩  郭靖  李登峰 《土壤》2019,51(5):843-853
土壤呼吸是陆地生态系统与大气之间进行碳交换的主要途径,其动态变化直接影响着全球碳平衡。由于人类活动的影响,酸雨成为人类当前面临的最严重的生态环境问题之一,但其对土壤呼吸的影响及其机理尚无定论。本文综述了不同生态系统土壤呼吸对酸雨的响应特征,多数文献表明,高强度的酸雨抑制土壤呼吸,而在低强度的酸雨作用下土壤呼吸的响应存在差异。从影响土壤呼吸的4个关键生物因子,即光合作用、微生物、凋落物和根系生物量,重点讨论了酸雨对土壤呼吸的影响机制。在此基础上,提出了以下研究展望:①开展土壤呼吸对不同组成类型酸雨的响应研究;②开展与土壤碳排放相关的功能微生物对酸雨的响应研究;③开展不同物候期土壤呼吸对酸雨的响应研究;④开展土壤呼吸各过程对酸雨的响应研究;⑤建立全球酸雨地区土壤碳排放监测研究网络。  相似文献   

4.
Shah  Jitendra J.  Nagpal  Tanvi  Johnson  Todd  Li  Jia  Peng  C. 《Water, air, and soil pollution》2001,130(1-4):235-240
China's continuing dependence on coal suggests a need for a cost-effective strategy to address SO2 and acid rain impacts. Results of modeling studies show that although there are important transboundary aspects of acid rain in Asia, the majority of emissions and damages lie within China. This implies that intra-regional cooperation within China, and cost-effective sulfur control are paramount for limiting acid rain damages. This article discusses the costs and benefits of six primary and secondary control and policy options using the RAINS-ASIA and UR-BAT models. The local health benefits were estimated to be an order of magnitude larger than the ecosystem benefits at the regional level. All abatement options involve substantial costs, except intensive energy efficiency which is the most cost effective with the rate of return of almost 200 per dollar as compared to around 6 for the other options.  相似文献   

5.
We analyze the history of acid rain in China over the last three decades in the light of the relationship between China and Japan. China has been aware of the problem of acid rain and has been conducting scientific research since the late 1970s. However, little effort has been put into practical countermeasures. In the early 1990s, acid rain was re-evaluated as an international environmental problem. Meanwhile, Japan became concerned about trans-boundary air pollution from China. What is important is that Japan's concern strongly influences China's acid rain policy. In the context of growing international concern for environmental problems, China has taken remarkable steps to control acid rain. In this respect, dealing with acid rain is an issue of national pride for China.  相似文献   

6.

Purpose  

Acid rain is a problem of increasing agricultural, environmental, and ecological concerns worldwide. In recent years, coupled studies have been conducted to evaluate impacts of simulated acid rain (SAR) on Latosol in China. However, no efforts have been devoted to investigating which soil parameters are most sensitive to the influences of SAR. In this study, we addressed the issue using the principal component analysis (PCA) and principal factor analysis (PFA) techniques.  相似文献   

7.
Li  Jinhui  Tang  Hongxiao  Bai  Qingzhong  Nie  Yongfeng  Luan  Zhaokum 《Water, air, and soil pollution》2000,117(1-4):251-261
With the aggravation of acid rain pollution and the enlarging of the acid rain regions in China, the sensitivity evaluation of natural waters to acidification on a regional scale become increasingly important. Acidification models based on a single indicator cannot give much information on aquatic acidification because of their simplicity; yet acidification models based on physical, chemical, hydrological and/or biological processes are not suitable for large scale regional research because of their exceptional complexity. In this paper, a multi-indicator comprehensive model for aquatic acidification sensitivity is proposed and applied. This model comprises some of the most important factors that are considered to influence water acidification, in particular: acid neutralization capacity, acidification capacity, acidification sensitive index, cation exchange capacity of soil, pH of soil, and weathering shuck types of soil-forming. It highlights the key stages of aquatic acidification by acid neutralization capacity, acidification capacity, and acidification sensitivity index. The model thereby estimates the acidification sensitivity of natural waters by using these indicators according to a weighting system. Equal-weight and non-equal-weight approaches are separately used to combine the six indicators into an overall sensitivity index of aquatic acidification. The result derived from an application to China on a national scale indicates the practicability of this approach. In China, the sensitive natural waters emerge in Southern China, which is already a heavy acid rain region, and in Northeastern China where the rainwater is beginning to become much acidic.  相似文献   

8.
A 5-year Chinese-Norwegian research project was launched in the autumn of 1999. Forested sites for intensive studies are or will be established in the Chongqing municipality and in Guizhou, Hunan and Guangdong provinces in southern China. Previous studies have shown that harmful effects of acid deposition are likely to be most severe in this region. The research and monitoring sites shall give information about acidification mechanisms and effects on vegetation in order to improve policy oriented acidification models and critical load estimates as well as function as interdisciplinary training centers for acid rain research. Furthermore, the project shall improve the basis for developing an efficient regional acid rain monitoring system. At one site in Guizhou and one in Chongqing, research on soil and soilwater chemistry has been ongoing for several years. The forest at these sites appears to show symptoms of reduced vitality. The sensitivity of Chinese forests to acidification is uncertain and will be focused. Decision-makers should get an improved basis for optimal mitigation measures through the project.  相似文献   

9.
10.
In this presentation research findings from the symposium and from the literature are utilized to examine some of the major hypotheses that link acidic deposition with impairment of forest health and productivity in central Europe and eastern North America. Although unequivocal evidence of acid rain damage may be lacking, there is a considerable body of knowledge that implicates air pollutants in recent interference with forest nutrition and health. The nature of the evidence and the inferences that can be drawn from it are still being vigorously debated. The problem of verifying the mechanisms by which air pollutants affect forests still remains. Reports that climatic irregularities have acted as inciting or triggering factors in forest declines are relevant to understanding regional damage. More emphasis on experimental studies that assess interactions of air pollutants and natural stresses with forests is needed.  相似文献   

11.
Mesoamerica provides a unique context for biodiversity conservation in managed landscapes because of its geography, history of human intervention, and present conservation and development initiatives. The long and narrow form of the Mesoamerican landmass, and its division by a central mountain range, has served as both a bridge and a barrier. Conservation efforts in Mesoamerica are unique for the emphasis they place on regional connectivity through the Mesoamerican Biological Corridor and on biodiversity conservation in managed landscapes. The emphasis on conservation in agricultural systems has fostered innovations in payment for ecosystem services, and provides novel insights on the functional role that biodiversity plays in the provisioning of ecosystem services. The increasing rate of economic development in the region and the advent of new payment for ecosystem service schemes have provided new opportunities for forest regeneration and restoration. However, the small scale of private landholdings and the diversity of land uses featured in the region, while contributing to biodiversity conservation due to their structural and floristic complexity, present challenges for biodiversity monitoring and management.  相似文献   

12.
酸雨对土壤生态系统影响的研究进展   总被引:14,自引:0,他引:14  
凌大炯  章家恩  欧阳颖 《土壤》2007,39(4):514-521
酸雨是人类当前面临的最严重的环境问题之-,并目益成为土壤学和生态学研究的热点.现有的大量研究表明,酸雨对土壤生态系统的功能特性,包括土壤的盐基离子以及重金属与微量元素的淋溶、土壤营养、土壤酸化、土壤微生物数量及其活性、土壤缓冲性能、土壤对酸雨的敏感性、土壤结构、土壤矿物风化等方面均会产生一定的影响.本文就酸雨对土壤生态系统特性的影响研究进展进行了综述,旨在为其他学者今后开展相关研究提供参考.  相似文献   

13.
模拟酸雨对不同园林植物叶片生理生态特性的影响   总被引:2,自引:0,他引:2  
采用盆栽方法,以自来水(pH值6.5)作为对照,研究了pH值为1.7,3.0,4.3,5.6模拟酸雨条件下新梢增长量、叶片损伤程度和叶片生理生态特性,并分析了园林植物对酸雨污染的敏感性反应。结果表明:不同pH值的酸雨对园林植物新叶片有不同程度的抑制,酸雨的酸度越大,对园林植物叶片的伤害越大,以pH值1.7的模拟酸雨对园林植物叶片的伤害最为严重,pH值5.6伤害较为轻微,但不同种类之间对酸雨的抗性有明显差异;pH值4.3~5.6处理对园林植物新梢生长率没有显著的影响和抑制作用,而pH值小于3.0处理则严重抑制了园林植物新梢生长;随模拟酸雨强度的增强,园林植物叶片的细胞质膜透性和丙二醛(MDA)含量逐渐升高,当pH值小于3.0时,细胞质膜透性和丙二醛(MDA)含量则急剧增加,当pH值为1.7时,不同园林植物叶片则严重受损;园林植物叶片叶绿素含量、叶片N和P含量随酸雨强度的增加逐渐降低,当pH值小于3.0时,园林植物叶片叶绿素含量、叶片N和P含量则急剧降低,当pH值为1.7时,不同园林植物叶片则严重受损;相关分析表明,酸雨增加了园林植物对环境的敏感性。园林植物对酸雨具有较强的抵抗能力,对园林植物生理活动影响的阈值pH值大致介于3.0~4.3,因此,本研究的6种园林植物可以作为酸雨灾害严重地区园林绿化及植被构建的物种。  相似文献   

14.
四川省成都市生态环境敏感性评价   总被引:3,自引:0,他引:3  
[目的]为了明辨四川省成都市现状自然环境背景下的潜在生态问题,指导区域生态保护和开发。[方法]在GIS空间分析技术的支持下,选择四种省成都市比较突出的土壤侵蚀、生境和酸雨3个生态环境要素建立敏感性评价指标,对成都市生态环境敏感性进行研究。[结果](1)成都市土壤侵蚀以轻度敏感为主,西部盆周山区是土壤侵蚀最为敏感的区域;(2)成都市生境敏感性以高度敏感为主,西部和东部生境敏感性较高,极敏感区域分布于西北部茶坪山、邛崃山一带;(3)成都市酸雨以轻度敏感为主,其次是中度敏感区,极敏感区主要分布在该市西部海拔1 650~3 200m的针阔叶混交林及高山原始针叶林地区;(4)成都市生态环境敏感性以不敏感为主,其次为中度敏感区和极敏感区,极敏感区域主要分布于西部盆周山区的北部和南部,分布有龙溪—虹口、白水河等国家级自然保护区。[结论]研究区高度敏感区和极敏感区主要分布在西部的盆周山区,是区域生态保护的重点区域。  相似文献   

15.
酸雨对黄土磷的淋溶效应   总被引:1,自引:0,他引:1  
采用室内土柱模拟淋溶试验,分析了陕西省杨凌区3种土壤在5个酸雨梯度的侵蚀作用下,土壤磷的释放和迁移规律.结果表明,酸雨会使土壤受到一定程度的酸化,而土壤的酸化程度与酸雨的pH值、土壤的类型、土壤的pH值、阳离子交换量、有机质含量有关.土壤对酸雨的缓冲能力由大到小的顺序为:腐殖质层>母质层>黏化层.随着酸雨累积淋溶量的增加,土壤磷的释放总量呈增加趋势,但淋失率会下降.酸雨的pH值为5时土壤磷的累积淋失量最大,土壤磷的累积淋失量和淋失率顺序为:腐殖质层>黏化层>母质层.酸雨对腐殖质层的磷具有最强侵蚀效应.母质层和黏化层的酸化主要发生在土壤表层,而腐殖质层酸化主要发生在土壤底层,酸雨侵蚀后腐殖质层酸化最严重.长期的酸雨侵蚀会导致土壤磷流失,造成土壤养分贫瘠化.  相似文献   

16.
The fate of much of the world’s terrestrial biodiversity is linked to the management of human-modified forest landscapes in the humid tropics. This Special Issue presents the first pan-tropical synthesis of research on the prospects for biodiversity in such systems, with eight individual regional summaries covering Mesoamerica, Amazonia, Atlantic forest of South America, West Africa, Madagascar, Western Ghats, Southeast Asia and Oceania. Two additional papers compare the state of conservation science in tropical forests with both temperate forests and savannah systems. This overview paper provides a comparative analysis of the threats and opportunities facing tropical forest biodiversity, thereby helping to identify the most pressing areas of future research and region-specific factors that contribute towards the effectiveness of individual conservation initiatives. While many of the threats facing tropical forest biodiversity are commonplace they vary markedly in their relative importance across different regions. There is a critical lack of comparable data to understand scale dependent processes, or the relative importance of varying geographic and historical contexts in determining present-day patterns. Conservation science has a key role to play in safeguarding the future of tropical forest biodiversity, but needs to become more effectively embedded in the context of real-world conservation challenges and opportunities. Significant progress can be achieved by improving the cost-effectiveness of research as well as the exchange of ideas and data amongst scientists working in different, often isolated parts of the world. We hope this special issue goes some way top achieving this exchange of knowledge.  相似文献   

17.
通过光谱分析技术,研究了模拟酸雨(SO-42:NO-31=5:1)对小麦产量和生理特性的影响。结果表明,模拟酸雨伤害了小麦叶片的结构和功能,降低了叶绿素含量和光合速率,从而显著降低了小麦的产量,经过pH为2的酸雨处理后的小麦产量降幅达19.1%。通过对植被指数的分析可以看出,小麦冠层叶绿素含量在开花期以后逐渐降低,而旗叶的叶绿素含量则在灌浆期以后开始下降,两者的下降幅度都随着酸雨pH的下降而增大。光合速率表现出与叶绿素含量相同的变化。另外,对小麦产量与不同生育期冠层和叶片水平的植被指数的相关分析表明,灌浆期的小麦冠层水平的NDVI、mND705和WI与酸雨处理后小麦的产量显著相关。总之,利用光谱分析技术可以快速、无损伤地监测不同酸雨处理对小麦的生长和营养状况的影响。  相似文献   

18.
19.
酸雨与镉对大豆幼苗光合作用复合影响的模拟试验   总被引:1,自引:0,他引:1  
采用生化分析方法、叶绿素荧光测定系统及透射电镜技术,测定不同强度酸雨与镉胁迫对大豆幼苗叶绿素含量、Hill反应速率、Mg2+-ATPase活性、荧光参数及叶绿体结构的复合影响。结果表明,与对照相比,单一酸雨和镉作用下,各指标随胁迫强度变化趋势为叶绿素含量(Hill反应速率和Mg^2+-ATPase活性)降低,初始荧光"先降后增",最大光化学效率和最大量子产量"先增后降"。酸雨与镉复合作用下,叶绿素含量的变化表现为上述单一作用的相加效应,Hill反应速率、Mg^2+-ATPase活性变化为单一作用的协同效应,荧光参数对酸雨与低(高)含量镉复合作用的响应表现为单一作用的拮抗效应(协同效应)。酸雨与镉复合作用下,叶绿体超微结构受到损伤。结合各指标变化进一步得出,叶绿体结构损伤是酸雨和镉对大豆幼苗叶绿素含量及光合光反应,乃至光合作用受抑的内在原因之一。  相似文献   

20.
基于近年中国西南频发的季节性旱灾事件,探讨了区域植被的水分适宜性。分析了区域性旱灾事件中蕴藏的重要科学问题——具有高耗水特性的桉树(Eucalyptus spp.)、橡胶树(Hevea spp.)人工林的生态需水是否适应于区域降水条件(或能否打破区域生态用水的供需平衡)进而导致旱害。同时分析了植被水分适宜性研究的现状与发展趋势,认为以植被生态需水计算为基础的植被水分适宜性研究进展缓慢且成果缺乏,作为水分适宜性评价基础的植被生态需水研究也存在一些问题。据此提出对云南省典型植被的水分适宜性及其生态需水与区域干旱的关系开展专项研究的建议。  相似文献   

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