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81.
The Commons in Transition: Agrarian and Environmental Change in Central and Eastern Europe 总被引:1,自引:0,他引:1
Sikor T 《Environmental management》2004,34(2):270-280
This paper analyzes institutional dynamics surrounding common-pool resources in postsocialist Central and Eastern Europe. It is conceived in close conjunction with the case studies by Penov, Schleyer, and Wasilewski and Krukowski (this issue). The purpose of this paper is to frame the individual case inquiries, compare their findings, and relate those to broader agrarian and environmental changes in the region.The case studies report a broad shift in resource governance from the previously dominant legal and administrative state hierarchies towards markets. In addition, state power has moved from central towards local authorities. The waning and decentralization of state power has caused the emergence of significant gaps between property legislation and rights-in-practice, which have been particularly stark in fragmented political systems. The discrepancy between legal texts and rights-in-practice leads to the exclusion of wider interests in favor of individual interests in the management of common-pool resources, resulting in resource deterioration and dwindling resource stocks. Thus, the comparative assessment suggests a tentative framework for understanding the effects of postsocialist transformations on governance of the commons and environmental change in Central and Eastern Europe. Its findings indicate an additional dimension to the diversity and distributive conflicts characterizing postsocialist privatization: the distribution of various rights to a resource among different actors. The findings also suggest the need for postsocialist states to take an active role in the governance of common-pool resources, particularly in the enforcement of legal rights.
Note: This version was published online in June 2005 with the cover date of August 2004. 相似文献
82.
Environmental assessment in countries in transition: evolution in a changing context 总被引:1,自引:0,他引:1
Cherp A 《Journal of environmental management》2001,62(4):357-374
Over the last fifteen years, Environmental Assessment systems of transitional societies of Central and Eastern Europe and Central Asia have undergone dramatic change from appraisals integrated into centrally planned economies to formal procedures aimed to ensure interdisciplinary analysis of environmental impacts and linked to publicly accountable decision-making. In most Central European nations, EA systems have been radically reformed to approximate the procedures used in developed countries, particularly in the European Union. In contrast, EA in most of the former Soviet republics has been reformed more gradually and is still based on the so-called State Environmental Review procedure inherited from the USSR and substantially different from 'Western' EA. About one-third of the transitional countries (in the Balkans, the Caucasus and Central Asia) have, so far, failed to establish functioning EA systems. Throughout the region, there has been a gap between EA legislation and practice, especially concerning interdisciplinary analysis of environmental impacts, public participation, and utilisation of EA findings in decision-making. A key driving force in the reform of EA systems has been the change in their societal context, the so-called 'process of transition'. Three main policy agendas--environmental protection, reforms of decision-making, and conforming to international requirements--along with the institutional context of EA regulations and practice have influenced both the change of EA systems over time and the regional variations in the patterns of their evolution. This study suggests that an effective reform of an EA system should be context-sensitive, or be 'in gear' with the political and economic transition. Future EA research should consider their changing societal contexts and focused on practical effects of applying EA procedures. 相似文献
83.
陕西关中近40年春季旱涝分析 总被引:1,自引:0,他引:1
对关中近40a6站3~4月降水量进行了标准旱涝等级分析和谐波分析,得出风调雨顺年份少,旱涝年份多,有2~3a及20a的显著周期。研究发现埃尔尼诺、太阳黑子相对数、西太平洋副高综合指数与旱涝变化规律有很好的对应关系,并有很高的相关系数。 相似文献
84.
ABSTRACT: The main factor in the location of medieval Cracow was drainage. In the 700-year history of the City, there were numerous changes in water conditions, particularly in channel network, runoff, ground water level, and ice phenomena. The most dangerous threat to surface water and ground water in Cracow in the last decades has been from industrial and municipal sewage. Currently there are no rivers that meet Drinking Water Quality standards in Cracow. The quality of the ground water has declined because of infiltration of contaminated river water, water from sewage disposal ponds, and pollution from the atmosphere and soil. Cracow does not have enough waste water plants to meet its needs. Most municipal and industrial sewage has not been treated or has been treated only partially. Because of considerable contamination of surface and ground waters in Cracow, more than half of the city's fresh water is pumped about 50 kilometers from a reservoir on the Raba River. A Polish government declaration of April 4, 1989, recognized Cracow as an area of particular protection, and directed that a number of actions be undertaken for the protection of environmental quality. 相似文献
85.
皖东地区野韭菜的开发与利用 总被引:1,自引:0,他引:1
文章介绍了野韭菜的基本生物特性,综合分析了其食用价值和潜在的药用价值,提出了野韭菜开发利用的基本对策。 相似文献
86.
为深入研究陕西省关中地区工业废水污染物排放特性和分布规律,文章采用等标污染负荷法,筛选确定了主要污染物,并重点分析了研究区主要污染物行业和区域分布特征。结果表明:关中地区主要污染物为COD、氨氮、石油类和挥发酚;这4类污染物主要来自于造纸及纸制品业、饮料制造业、化学原料及化学制品制造业等行业;主要排放区域为西安市、渭南市、咸阳市、宝鸡市。 相似文献
87.
关中地区人为源大气污染物排放清单研究 总被引:5,自引:0,他引:5
首次以关中地区为研究对象,通过收集各排放源的活动水平数据,选取国内外研究中的排放因子,采用排放因子法“自上而下”建立了2011年关中地区人为源大气污染物排放清单.结果表明:2011年关中地区人为源SO2、NOx、CO、PM10、VOCs、NH3的排放量分别为400.254×103 t、342.412×103 t、2 731.302×103 t、573.193×103 t、350.523×1 03 t、323.312×103t.其中渭南是SO2、NOx、CO的主要排放城市,西安是VOCs的主要排放城市,咸阳是NH3的主要排放城市,咸阳、铜川同为PM10的主要排放城市;SO2、NOx、CO的主要排放源为工业用煤炭燃烧,VOCs的主要排放源为炼焦、涂料等工业生产过程,PM10的主要排放源为农田秸秆燃烧,NH3的主要排放源为农业化肥施用.清单的不确定性来自活动水平数据的不完善及排放因子缺乏本地特征两方面.为提高清单的可信度,将研究结果与其他排放清单进行比较,结果表明差异度较小. 相似文献
88.
海南东部河口和近岸海域总溶解态无机砷的分布及季节变化 总被引:2,自引:0,他引:2
利用氢化物发生原子荧光法对2006年12月和2007年8月航次海南东部河流、河口、近岸及地下水中的总溶解态无机砷(total dissolved inorganic arsenic,TDIAs,As5++As3+)进行了测定.2006年12月万泉河及河口、文昌/文教河及河口、近岸TDIAs的浓度分别为4.0~9.4、1.3~13.3、13.3~17.3 nmol.L-1,2007年8月万泉河及河口、文昌/文教河及河口、近岸、地下水TDIAs的浓度分别为1.6~15.5、2.4~15.9、10.8~17.6、未检出~41.7 nmol.L-1.结果表明,万泉河及文昌/文教河河流、河口TDIAs的浓度不存在显著性季节变化,较我国及世界其它河流、河口偏低,处于自然状态.砷在万泉河口和文昌/文教河口混合过程中均表现为保守混合.以文昌/文教河为例,初步估算出2007年文昌/文教河口地下水向沿岸砷的输送通量为1 153 mol.a-1,约为文昌/文教河砷入海通量的二分之一,表明海南东部沿岸地下水也是沿岸海区砷的主要来源之一. 相似文献
89.
Philip J. Platts Colin J. McClean Jon C. Lovett Rob Marchant 《Ecological modelling》2008,218(1-2):121-134
The Eastern Arc Mountains (EAMs) of Tanzania and Kenya support some of the most ancient tropical rainforest on Earth. The forests are a global priority for biodiversity conservation and provide vital resources to the Tanzanian population. Here, we make a first attempt to predict the spatial distribution of 40 EAM tree species, using generalised additive models, plot data and environmental predictor maps at sub 1 km resolution. The results of three modelling experiments are presented, investigating predictions obtained by (1) two different procedures for the stepwise selection of predictors, (2) down-weighting absence data, and (3) incorporating an autocovariate term to describe fine-scale spatial aggregation. In response to recent concerns regarding the extrapolation of model predictions beyond the restricted environmental range of training data, we also demonstrate a novel graphical tool for quantifying envelope uncertainty in restricted range niche-based models (envelope uncertainty maps). We find that even for species with very few documented occurrences useful estimates of distribution can be achieved. Initiating selection with a null model is found to be useful for explanatory purposes, while beginning with a full predictor set can over-fit the data. We show that a simple multimodel average of these two best-model predictions yields a superior compromise between generality and precision (parsimony). Down-weighting absences shifts the balance of errors in favour of higher sensitivity, reducing the number of serious mistakes (i.e., falsely predicted absences); however, response functions are more complex, exacerbating uncertainty in larger models. Spatial autocovariates help describe fine-scale patterns of occurrence and significantly improve explained deviance, though if important environmental constraints are omitted then model stability and explanatory power can be compromised. We conclude that the best modelling practice is contingent both on the intentions of the analyst (explanation or prediction) and on the quality of distribution data; generalised additive models have potential to provide valuable information for conservation in the EAMs, but methods must be carefully considered, particularly if occurrence data are scarce. Full results and details of all species models are supplied in an online Appendix. 相似文献
90.
Françoise Henry Céline Mahfouz Alice Delegrange Lucie Courcot 《Chemistry and Ecology》2017,33(4):271-280
Mercury (Hg) in fish can present a potential risk to wildlife and human consumers. Mercury levels were determined in 12 fish species and 2 invertebrate species from the French coast of the Eastern English Channel collected in June and November 2012. Total mercury concentrations in the muscle tissues ranged between 0.04 and 1.63 µg g-1 (d.w.). Dab and sandeel displayed a significant positive correlation between Hg concentrations and fish length. Seasonal differences in Hg concentrations were observed for dab and shrimp. The lesser weever showed significantly higher concentrations of Hg (0.97 ± 0.34 µg g-1 d. w.) than all other species. Gobies and sprat, which had the smallest size, showed significantly lower concentrations than herring, whiting, pout and sardine. Among the considered species, flatfish such as dab, flounder, plaice and sole displayed intermediate levels of Hg. In the present study, the fish age expressed as specimen length seems to be one of the major factors governing Hg contents in muscle tissues. Finally, mercury concentrations in commercial fish from the Eastern English Channel were below the levels fixed by the European Union for total mercury in edible parts of fish products. 相似文献