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The aim of this paper is to show the concise chemico-physical adsorbent performance of water purification systems utilizing geo-(e.g., allophane, clinoptilolite, and smectite) and bio-polymer materials(e.g.,chitosan or cellulose nanocomposite materials) and to propose an optimal ground-water remediation technique. The performance of geo-materials is evaluated based on the individual sorption and immobilization capacities for various priority substances and pollutants(e.g., lead, zinc, cadmium, c... 相似文献
283.
Participatory scenario planning (PSP) processes rely on accurate stakeholder identification to develop a key set of critical uncertainties. While many stakeholder analysis methods are able to identify stakeholders and describe their relationships, we found these efforts to have limited use in the fast-moving and in-depth approach of PSP research. We find that social network analysis (SNA) is an efficient, objective, and transparent approach to stakeholder identification in highly contested natural resource management issues. We present a case study of our research on Alaska’s Kenai Peninsula to describe how SNA’s ability to contextualize the relations between actors can benefit participatory research. 相似文献
284.
上海市的发展战略;空间布局模式和环境管理是文章讨论的三个主要问题。作者认为:(1)战略设想要立足于上海的发展,“开发浦东、振兴上海、服务全国、面向世界;”(2)新的空间布局模式应为“逐步形成新的CBD,强化和完善金融和服务功能”;(3)城市发展和环境建设要协调。文章着重讨论了上海城市发展中出现的环境问题及其治理的对策和措施。 相似文献
285.
Andrea K. Gerlak Tanya Heikkila Sharon L. Smolinski Derek Armitage Dave Huitema Brendan Moore 《社会与自然资源》2019,32(9):1056-1064
This Commentary reflects on the state of the scholarship on learning for environmental and natural resource policy and governance. How have we been learning about learning? We highlight theoretical and empirical advancements related to learning, as well as areas of divergence between learning theories and frameworks, and underdeveloped knowledge around processes and outcomes. To address these limitations and improve progress in both theory and practice, we offer recommendations for learning scholarship by focusing on how to collectively engage in ‘learning about learning’. 相似文献
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287.
Snow chemistry on the glaciers of alpine regions is a good indicator of atmospheric environmental change.We examine snow chemistry in three snowpits at different altitudes on the Haxilegen Glacier No.51,in the Kuitun River source,Tian Shan,China,during July-September 2004 to 2007.We use correlation analysis,factor analysis and sea-salt tracing methods to examine the characteristics and sources of major ions and mineral dust particles in the snow.Results show that mineral dust particles and major ions in the snow pits vary seasonally.During the Asian dust period in springtime,the concentration of mineral dust particles and major ions deposited in snow is high,while the concentration is relatively low during the non-dust period of summer and autumn.This may be caused by dust storm activity in central Asia.The order of major ionic concentrations in the snow packs was determined to be Ca2+ > SO42-> NH4+ > NO3-> Cl-> Na+ > Mg2+ > K+.Ca2+ was the dominant cation;SO42- was the dominant anion.We find,with the exception of NO3-,that the variabilities of ionic concentrations are highly correlated.Results show that the glacier region was significantly affected by dust activity and anthropogenic source.The major ions,especially Na+,originate from dust sources of central Asia and from the Ocean,transported by the westerly winds. 相似文献
288.
《Marine Policy》2017
The EU enlargement brought the Baltic Sea into the sphere of EU environmental policymaking, making the sea, with the exception of Russia, an EU inland sea. Yet, the state of the Baltic Sea environment is deteriorating at an alarming pace. This paper describes the evolution of the EU governance of the Baltic Sea environment, focussing on governance barriers. The findings demonstrate how the choice of analytical lens influences the construction of governance barriers and the respective intervention strategies. Such understanding can help policy practitioners in their search for successful measures to improve the governance situation in the Baltic Sea region. 相似文献
289.
From pastoralism to tourism: The historical impact of changing land use practices in Namaqualand 总被引:1,自引:2,他引:1
We use the concept of ecological revolutions to explain the environmental history of Namaqualand, from the advent of pastoralism 2000 years BP, to colonial settlement in the 18th century and finally to the recent trend of de-agrarianization from the middle of the 20th century. Early traveller's records and census data are used to assess changes in the human population of the region and how this affected wildlife and agricultural practices. Pre-colonial indigenous hunter-gatherer (Bushmen) and pastoralist (Khoekhoen) populations in Namaqualand consisted of probably no more than a few thousand individuals. Over the next three centuries, the general population rose steadily to more than 65,000 people but has fallen in recent years. Wildlife appears not to have been abundant in Namaqualand's pre-colonial landscapes and large springbok ‘treks’ were probably a rare event. The number of domestic livestock in Namaqualand peaked in 1957 largely as a result of an increase in the number of sheep which have fallen steadily since this time. Crop production was absent from Namaqualand's pre-colonial landscapes but increased to cover nearly 30,000 ha in the early 1970s. The area under cultivation has declined by nearly two thirds since this time largely as a result of the large-scale abandonment of wheat farming in marginal environments. We touch on differences between the communal areas and private farms, particularly in terms of their human populations and agricultural impact on the land. Repeat landscape photographs support our main findings which suggest that both rocky, upland habitats and rivers have not been transformed substantially by land use practices in Namaqualand. Instead, sandy pediments have borne the brunt of human impacts in the region. Finally, we highlight the beginning of a new ecological revolution in Namaqualand due to changes in the global and national political economy. 相似文献
290.
图们江地区水环境容量及其对区域开发的影响研究 总被引:9,自引:1,他引:9
以COD为控制指标,计算了图们江地区5条河流逐月环境容量以及污水达标排放时的允许污水排放量。结果表明,各月环境容量分配极不均匀,丰水期2个月约占50%,而长达5个月的枯水期环境容量很小,不足全年的10%;即使以1995年污水排放量衡量,污水达标排放时,枯水期图们江干流等5条河流控制断面水质也达不到指定功能水质标准,已无环境容量可利用。因此,河流水环境容量已成为制约图们江地区开发的主要因素,为了确保 相似文献