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1.
ABSTRACT

Engaging with normative questions in land system science is a key challenge. This debate paper highlights the potential of incorporating elements of environmental justice scholarship into the evolving telecoupling framework that focuses on distant interactions in land systems. We first expose the reasons why environmental justice matters in understanding telecoupled systems, and the relevant approaches suited to mainstream environmental justice into telecoupled contexts. We then explore which specific elements of environmental justice need to be incorporated into telecoupling research. We focus on 1) the distribution of social-ecological burdens and benefits across distances, 2) power and justice issues in governing distantly tied systems, and 3) recognition issues in information flows, framings and discourses across distances. We conclude our paper highlighting key mechanisms to address injustices in telecoupled land systems.  相似文献   

2.
Statistical methods as developed and used in decision making and scientific research are of recent origin. The logical foundations of statistics are still under discussion and some care is needed in applying the existing methodology and interpreting results. Some pitfalls in statistical data analysis are discussed and the importance of cross examination of data (or exploratory data analysis) before using specific statistical techniques are emphasized. Comments are made on the treatment of outliers, choice of stochastic models, use of multivariate techniques and the choice of software (expert systems) in statistical analysis. The need for developing new methodology with particular relevance to environmental research and policy is stressed.Dr Rao is Eberly Professor of Statistics and Director of the Penn State Center for Multivariate Analysis. He has received PhD and ScD degrees from Cambridge University, and has been awarded numerous honorary doctorates from universities around the world. He is a Fellow of Royal Society, UK; Fellow of Indian National Science Academy; Foreign Honorary Member of American Academy of Arts and Science; Life Fellow of King's College, Cambridge; and Founder Fellow of the Third World Academy of Sciences. He is Honorary Fellow and President of International Statistical Institute, Biometric Society and elected Fellow of the Institute of Mathematical Statistics. He has made outstanding contributions to virtually all important topics of theoretical and applied statistics, and many results bear his name. He has been Editor of Sankhya and theJournal of Multivariate Analysis, and serves on international advisory boards of several professional journals, includingEnvironmetrics and theJournal of Environmental Statistics. This paper is based on the keynote address to the Seventh Annual Conference on Statistics of the United States Environmental Protection Agency.  相似文献   

3.
环境成本核算研究的进展   总被引:4,自引:0,他引:4  
蒋洪强  徐玖平 《生态环境》2004,13(3):429-433
环境成本核算作为环境管理的基础工作,在绿色国民经济核算体系构建,在涉及环境费用效益分析,在制定适当的环境标准、环境收费等政策时发挥着重要作用。在陈述环境成本的定义和分类以及国内外环境成本核算研究过程的基础上,指出可持续发展理论、总成本理论、外部性和边际机会成本理论以及基于SEEA核算体系的环境成本计量理论是环境成本核算的四大理论支柱,并对环境成本核算方法的研究进行了总结与分析。阐明了研究队伍综合化、宏观核算微观化、核算方法科学化是环境成本核算研究的发展趋势,时空范围的处理、环境服务产出的处理、内部环保外部化处理是环境成本核算研究的难点与热点问题。  相似文献   

4.
5.
Quantifying the manner in which ecological communities respond during a time of decreasing precipitation is a first step in understanding how they will respond to longer-term climate change. Here we coupled analysis of interannual variability in remotely sensed data with analyses of bird and butterfly community changes in montane meadow communities of the Greater Yellowstone Ecosystem. Landsat satellite imagery was used to classify these meadows into six types along a hydrological gradient. The northern portion of the ecosystem, or Gallatin region, has smaller mean patch sizes separated by ridges of mountains, whereas the southern portion of the ecosystem, or Teton region, has much larger patches within the Jackson Hole valley. Both support a similar suite of butterfly and bird species. The Gallatin region showed more overall among-year variation in the normalized difference vegetation index (NDVI) when meadow types were pooled within regions, perhaps because the patch sizes are smaller on average. Bird and butterfly communities showed significant relationships relative to meadow type and NDVI. We identified several key species that are tightly associated with specific meadow types along the hydrological gradient. Comparing taxonomic groups, fewer birds showed specific habitat affinities than butterflies, perhaps because birds are responding to differences in habitat structure among meadow types and using the landscape at a coarser scale than the butterflies. Comparing regions, the Teton region showed higher predictability of community assemblages as compared to the Gallatin region. The Gallatin region exhibited more significant temporal trends with respect to butterflies. Butterfly communities in wet meadows showed a distinctive shift along the hydrological gradient during a drought period (1997-2000). These results imply that the larger Teton meadows will show more predictable (i.e., static) species-habitat associations over the long term, but that the smaller Gallatin meadows may be an area that will exhibit the effects of global climate change faster.  相似文献   

6.
大型底栖无脊椎动物是河流生态系统的重要组成生物,具有活动范围相对固定、生命周期较长、生活习性相对稳定等特点,可有效指示河流水质和水生态系统健康状况。有关大型底栖生物群落结构特征及其与水环境之间的关系研究一直是河流生态系统的研究热点。底栖动物具有较强的地域性,其群落结构特征受当地的自然环境特征和社会经济发展程度的双重因素影响。为研究典型平原河网地区的底栖动物群落结构及对水环境状况的响应特征,在上海市选取了83个河道断面进行大型底栖动物采样分析,共获取底栖动物20个分类单位(种),其中软体动物10种,环节动物6种,节肢动物4种。上海河道底栖动物群落结构总体呈现结构单一、物种丰富度低、高度耐污性等显著特征,环节动物的栖息密度和出现频率均最高。城市化水平的空间差异性直接影响底栖动物空间分布的异质性,由市区至近郊、远郊,物种数从11种逐渐上升至15种,而栖息密度则由8 776.3个/m2下降至690.3个/m2。底栖动物群落结构的空间分布特征与水质理化指标的空间分布特征具有良好的对应性,水质空间变化导致环节动物和软体动物、节肢动物的空间分布存在一定交错性,耐污性较强的环节动物主要分布在有机污染重、溶解氧低的市区河道断面,而喜清洁环境的软体动物和节肢动物主要分布在水质较好的郊区断面。寡毛纲物种的栖息密度与溶解氧质量浓度呈显著负相关性。  相似文献   

7.
黑碳对污染物环境地球化学过程的影响   总被引:8,自引:1,他引:8  
黑碳是生物体和化石燃料不完全燃烧形成的一种富含芳香族基团的产物,普遍存在环境中.由于其具有超强的吸附能力,影响污染物在环境中的存在形态,进而影响其生物有效性,并最终改变污染物的归宿.因此,有必要考察黑碳对环境中的污染物的环境行为的影响进行研究,才能更加准确地预测污染物在环境中的归趋.文章在黑碳对污染物的吸附及其影响因素、黑碳对污染物的生物毒性和污染物的生物降解影响方而进行了综述,并提出黑碳对污染物环境地球化学过程影响的末来研究方向.  相似文献   

8.
The purpose of this brief article is to describe ecological and environmental research at the International Institute for Applied Systems Analysis (IIASA). Because IIASA represents an unusual, perhaps-even unique experiment in science, an understanding of its origins, objectives, and mode of operation provides an important background and perspective for veiewing the research.  相似文献   

9.
硝基苯环境效应的研究综述   总被引:5,自引:0,他引:5  
硝基苯污染威胁着人类和生态系统健康,国外有关硝基苯的环境毒理的研究已经广泛展开,但我国仍处于起步阶段.文章综述了国内外硝基苯环境效应的研究进展,介绍了其基本理化性质、用途、环境基准和标准值、污染的生态毒理效应以及其在生态系统中的迁移转化规律.研究认为环境中的硝基苯属于低毒污染物,但难溶于水,易溶于有机溶剂,难以降解,造成水体和土壤污染的持续时间长,且能够在生物体内积累,产生生物放大效应,因此,高浓度的硝基苯对生态系统和人体健康造成较大的生态风险;不过,阳光中的近紫外线、γ射线、声波振荡以及生物分解等作用可自然环境中硝基苯有降解作用,而生物和物理吸附能降低其浓度,从而降解其毒性.目前,有关自然生态系统中硝基苯迁移转化过程之间协同作用与相互影响的研究还有待于进一步深入.  相似文献   

10.
James E. Lovelock, famed for his Gaia hypothesis, which views the Earth as a living integrated and interconnected self-regulating system whose equilibrium comes about from complex energy-based interactions and feedback loops, ultimately sustaining life, passed away at the end of July, 2022 at the age of 103. Not only are the adaptive mechanisms of Gaia central to the conversation of environmental homeostasis, they lie at the heart of climate change and global warming. Lovelock is also remembered as the co-inventor of the electron capture detector that eventually allowed for the sensitive detection of chlorofluorocarbons and pesticides. Finally, Lovelock’s free-spirited nature and research independence allow academia to rethink current research’s modus operandi.  相似文献   

11.
北仑河口地处亚热带-热带地区,气候温暖湿润,是我国北部湾沿岸与越南交界的一个重要入海河口。于2008年3、5、8和11月分别采集该海域小型浮游硅藻,同时测定水温、盐度等水体参数,以及氮、磷、硅等18项水化学指标,分析了小型硅藻群落结构变化与环境因子之间的关系。该河口区的小型硅藻主要由纤细翼鼻状藻Proboscia alata f.gracillima、拟旋链角毛藻Chaetoceros pseudocurvisetus、细弱海链藻Thalassiosira subtilis、中华齿状藻Odontella sinensis和菱形藻Nitzschiasp.等优势种类组成,并且存在明显的季节性演替。应用典范对应分析,发现影响北仑河口硅藻群落结构的主要环境因子为温度、盐度、N、Si、Hg和悬浮体质量浓度等,且不同季节的主控因素有所差异。菱形藻对温度和Cu、As、Zn和Hg等重金属的耐受性较强。纤细翼鼻状藻适宜于生长在水体透明度高的海域,悬浮体质量浓度以6.27 mg.L-1以下为宜。拟旋链角毛藻受Cr的影响较大,高含量的Cr会限制其生长。而细弱海链藻和中华齿状藻对Hg的耐受性较强。  相似文献   

12.
北仑河口海域小型硅藻群落结构及其与环境因子的关系   总被引:1,自引:0,他引:1  
北仑河口地处亚热带-热带地区,气候温暖湿润,是我国北部湾沿岸与越南交界的一个重要入海河口。于2008年3、5、8和11月分别采集该海域小型浮游硅藻,同时测定水温、盐度等水体参数,以及氮、磷、硅等18项水化学指标,分析了小型硅藻群落结构变化与环境因子之间的关系。该河口区的小型硅藻主要由纤细翼鼻状藻Proboscia alata f.gracillima、拟旋链角毛藻Chaetoceros pseudocurvisetus、细弱海链藻Thalassiosira subtilis、中华齿状藻Odontella sinensis和菱形藻Nitzschiasp.等优势种类组成,并且存在明显的季节性演替。应用典范对应分析,发现影响北仑河口硅藻群落结构的主要环境因子为温度、盐度、N、Si、Hg和悬浮体质量浓度等,且不同季节的主控因素有所差异。菱形藻对温度和Cu、As、Zn和Hg等重金属的耐受性较强。纤细翼鼻状藻适宜于生长在水体透明度高的海域,悬浮体质量浓度以6.27 mg.L-1以下为宜。拟旋链角毛藻受Cr的影响较大,高含量的Cr会限制其生长。而细弱海链藻和中华齿状藻对Hg的耐受性较强。  相似文献   

13.
Deep-water assemblages of suprabenthic peracarids were analyzed in the SW Balearic Islands (Algerian Basin, southwestern Mediterranean) between 249 and 1,622 m depth; the patterns of species composition, possible zonation, and trophic structure found in this area were compared with those exhibited by peracarids in the mainland side of the Catalan Sea slope (northwestern Mediterranean). One hundred and four peracarid species (plus one leptostracan) were identified on the Balearic Islands slope, amphipods being the most diversified taxon (45 species). On the Balearic slope, two distinct depth assemblages were distinguished: one at the upper slope (US), between 249 and 402 m depth and the second at the deep slope, between 543 and 1,620 m depth. A remarkable species substitution occurred at depths between 402 and 638 m. In the Catalan Sea, in addition to the US assemblage occupying depths between 208 and 408 m, a second boundary of faunal change was found around 1,250 m. Suprabenthos biomass increased from 242 to approximately 500 m. Suprabenthos attained the highest biomass values (100 g wet weight/10,000 m2) at intermediate depths between 504 and 1,211 m, as also occurred with the associated zooplankton collected with suprabenthos (peak biomass between 502 m and 898 m). Suprabenthos biomass did not show any significant correlation with any environmental water-column variable. In contrast, zooplankton (especially small fish and decapod crustaceans) showed a significant positive correlation with fluorometry and turbidity at different levels of the water column. The feeding guilds of species showed important differences between the two areas only on the US, with a higher abundance of deposit feeders in the Catalan Sea (20.4%) than in the Balearic Islands (4.2%). The low contribution of deposit feeders in the SW Balearic Islands may ultimately be a consequence of the lack of river discharges in this area.Communicated by S.A. Poulet, Roscoff  相似文献   

14.
Increasing human populations along marine coastlines has lead to increasing urbanization of the marine environment. Despite decades of investigations on terrestrial ecosystems, the effect of urbanization on marine life is not well understood. Riprap is the rocky rubble used to build jetties, breakwaters, and armored shorelines. Roughly 30% of the southern California shoreline supports some form of riprap, while 29% of the shoreline is natural rocky substrate. Astonishingly few studies have investigated this anthropogenic rocky habitat even though it rivals a natural habitat in area on a regional scale along a coastline that has been extensively studied. In this study, I compared the diversity and community structure of exposed rocky intertidal communities on four riprap and four natural sites in southern California. I ask the following questions: (1) does diversity or community composition differ between intertidal communities on riprap and natural rocky habitats in southern California, (2) if so, which organisms contribute to those differences, (3) which physical factors are contributing to these differences, and (4) do riprap habitats support higher abundances of invasive species than natural habitats? On average, riprap and natural rocky habitats in wave exposed environments in southern California did not differ from each other in diversity or community composition when considering the entire assemblage. However, when only mobile species were considered, they occurred in greater diversity on natural shores. These differences appear to be driven by wave exposure. The presence of invasive species was negligible in both natural and riprap habitats.  相似文献   

15.
手性农药对映体选择性环境行为的研究进展   总被引:3,自引:0,他引:3  
目前使用的农药中有25%是手性的,手性农药的生物活性存在对映体差异性,其活性往往只存在于一个或少数几个对映体中,而手性农药的对映体在环境中的消解和归趋往往也有明显的不同,即一个手性化合物的不同对映体具有不同的毒性.只有在对映体水平上研究手性农药的环境行为,考察手性农药的归趋和生态效应,才能更准确的评估其生态风险性以及对人类健康的影响,对手性农药的合理使用也有较好的指导作用.文章综述了近年来国际上有机氯、芳氧基羧酸和酰胺、有机磷和菊酯等手性农药对映体选择性环境行为的研究进展.提出今后的研究方向是拓展手性农药的研究种类、研究深度和广度,对映体选择性的毒理学研究,手性稳定性和手性转化,选择性的机制与相关微生物和酶学研究等.  相似文献   

16.
A statistical modeling study was performed on the population fluctuations of the 15 commonest fish species frequenting the tidal Scheldt estuary in Belgium. These included marine juvenile and seasonal visitors, estuarine residents and diadromous fish species that were recorded on the filter screens of a power plant cooling-water intake between September 1991 and April 2001. The species population abundance was regressed against a candidate set of 6 environmental variables and 13 instrumental variables, accounting for seasonality and long-term trends present in the data. Population abundances of the different species were, in general, best described by seasonal variables. Seasonal components contributed, on average, up to 63.8% of the variance explained by the models. Ten species were found to show a slightly negative, though significant, trend over the period of the survey. Most models also included at least one environmental variable, and 25.4% of the explained variance could be attributed to environmental fluctuations. Of all physico-chemical variables, dissolved oxygen was the most important predictor of fish abundance, suggesting that the estuary suffered from poor water quality during the survey. Temperature, salinity, freshwater flow, suspended solids and chlorophyll a concentrations were minor determinants of fish abundance.Communicated by O. Kinne, Oldendorf/Luhe  相似文献   

17.
Attempts to better understand the social context in which conservation and environmental decisions are made has led to increased interest in human social networks. To improve the use of social-network analysis in conservation, we reviewed recent studies in the literature in which such methods were applied. In our review, we looked for problems in research design and analysis that limit the utility of network analysis. Nineteen of 55 articles published from January 2016 to June 2019 exhibited at least 1 of the following problems: application of analytical methods inadequate or sensitive to incomplete network data; application of statistical approaches that ignore dependency in the network; or lack of connection between the theoretical base, research question, and choice of analytical techniques. By drawing attention to these specific areas of concern and highlighting research frontiers and challenges, including causality, network dynamics, and new approaches, we responded to calls for increasing the rigorous application of social science in conservation.  相似文献   

18.
To explore whether and why people sometimes reject environmental policies that improve individual and collective outcomes, we create an experimental market in which transactions generate a negative externality. Market participants endogenously determine whether to implement corrective policies. We consider three policy instruments (Pigouvian taxes and subsidies, and quantity regulation) and two levels of policy efficiency (full and half). We then explore how individual cultural worldviews might contribute to the rejection of policies that correct the market failure. Our results indicate that people often oppose policies that improve their material outcomes, and we find that such opposition is significantly explained by cultural worldviews. Interesting connections emerge between individual worldviews and specific policy instruments.  相似文献   

19.
彭涛  杨滨  徐超  杨雷  应光国 《环境化学》2020,39(4):876-890
化学品的大量生产和使用对环境和人们构成生态和健康风险.近年来量子化学研究方法广泛应用于化学品环境污染过程与归趋研究,理论计算结果均得到传统实验研究的较好验证.因此,本文综述了量子化学计算在化学品环境污染研究中的诸多应用.文章首先简介了量子化学基本原理及计算内容,阐述了小分子基态及激发态、生物大分子和无机大分子的量子化学计算方法及在化学品环境污染领域中的应用,结合过渡态理论,半定量计算可以得到化学品在环境中发生的迁移转化行为,从而为化学品环境管理和风险评估提供基础数据和理论依据.  相似文献   

20.
Hsieh CH  Ohman MD 《Ecology》2006,87(8):1932-1938
Determining the relative contributions of intrinsic and extrinsic processes to the regulation of biological populations has been a recurrent ecological issue. Recent discussions concerning ecosystem "regime shifts" again raise the question of whether population fluctuations are mainly controlled by external forcing. Results of nonlinear time series analyses indicate that pelagic populations typically do not passively track stochastic environmental variables. Rather, population dynamics are better described as nonlinear amplification of physical forcing by biological interactions. However, we illustrate that in some cases populations do show linear tracking of the physical environment. To explain why population dynamics can sometimes be linear, we propose the linear tracking window hypothesis: populations are most likely to track the stochastic environmental forcing when their generation time matches the characteristic time scale of the environmental signal. While our observations follow this hypothesis well, our results indicate that the linear tracking window is a necessary but not a sufficient condition.  相似文献   

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