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891.
SUMMARY

The emerging concept of industrial ecology (IE) has been applied in practice in few case studies on local/regional industrial recycling networks. Analogously to a natural ecosystem, the aim is to develop material cycles and energy cascades between local cooperative actors. An optimal resource basis of an industrial ecosystem is the sustainable use of local renewable natural resources. In this paper, we consider the region of North Karelia in Finland, with 19 municipalities, and hence somewhat expand the system boundaries of an industrial ecosystem case study. The current situation and two scenarios of municipal heating energy production are presented. The heating system consists of individual, district and electric heating. The heat production and related greenhouse gas emissions are considered. The current fuel use is based on imported oil and regional fuels (peat, wood wastes). Also, shares for co-production of heat and electricity (CHP) are shown. In scenario one, we assume the majority of the fuel basis in oil and absence of CHP. Scenario two illustrates nearly complete dependence on regional wood wastes and firewood with the current share of CHP. The North Karelia region provides the IE theory with a fruitful case study because the supply of waste fuels and local renewables is vast and waste utilisation technologies (CHP, fluidized bed burning) constitute a significant part of energy production. Implications of the applied scenario approach are discussed in the context of regional decision making and, in particular, for its implementation with the concepts of a regional environmental management system (EMS) and a regional industrial ecosystem management system (RIEMS).  相似文献   
892.
Vermetid reefs are among the most important bioconstructions in the Mediterranean Sea, with a distribution restricted to the warmest part of the basin. Their structure, and vertical and geographical distribution make them good biological indicators of changes in sea level and sea-surface temperature over the last two millennia.  相似文献   
893.
In 1986, application of lime within the upper wetland area of sector VII of the Loch Fleet catchment initiated numerous unscheduled small-scale experiments on the vegetation of this heterogeneous terrain. Vegetation changes and erosion were monitored in permanent or relocated plots established in 1987 and 1989 and re-surveyed in 1993, seven years after liming.

The most striking early effect, possibly occurring within a few weeks of lime application, was the death of Sphagnum papillosum carpet in soakways within the 2.5 ha area. Some patches of dead material were washed away, but bare surfaces were generally colonised by vascular plants, notably Juncus bulbosus. Effects in moorland and bog communities with dwarf shurbs were more subtle, involving reduction in Sphagnum cover and expansion of Erica teralix, Molinia caerulea, sedges and Narthecium ossifragum, but little change in the frequency of occurrence of Calluna vulgaris.  相似文献   
894.
SUMMARY

Reclaiming farmland from lakes in China in the 1950s damaged the water quality of many lakes. Tremendous efforts have been made since the late 1990s to restore vegetation around the damaged lakes. This paper examines water quality of Fuxian and Qilu Lakes and land-use characteristics within the two catchments in the high-altitude area of Yunnan Province, China. Landsat TM data acquired in 1989, 1994, 1999 and 2005 were used to extract land use and land cover (LULC) information. Measurements of five water quality indices (WQIs), BOD, COD, pH, TN and TP, for the same period of time were examined. The results showed that the area of residential and forest/shrub increased, whereas that of cropland and barren land decreased from 1989 to 2005 in both catchments. Qilu Lake was much more polluted than Fuxian Lake, and pollution worsened over time for both lakes. The differences in water quality between the two lakes were caused by differences in LULC composition and continued degradation in water quality was caused by intensive farming and urban sprawl. Unless the landscape is converted back to its pre-1950 composition and structure, water quality in both lakes cannot be significantly improved and will continue to threaten sustainable development in the region.  相似文献   
895.
Africa is most vulnerable to climate change, although it makes the least contribution to factors that result in global and regional climatic changes. High levels of vulnerability and low adaptive capacity across the continent have been linked to, among other things, poverty. This paper discusses and analyses the relationship between climate change and poverty in Africa. It investigates the relationship between climate change and poverty patterns in Africa, analyses the resultant impact, and discusses potential adaptation policies for moderating the consequences of climatic changes on poverty in the region. The record shows that climate change is happening. What is not discussed or is little researched is the potential devastating impact of climate change on socio-economic development in Africa and the policy measures available to the continent for adaptation.  相似文献   
896.
ABSTRACT

This study investigates the structural linkages of product quality, corporate image, store image, and price on customer satisfaction and loyalty towards green products usage in Malaysia. The research used structural equation modelling technique via AMOS 21.0 computer program for data analysis across a sample of 200 university students who applies a green lifestyle, such as purchasing green products which are referring to only retail goods, using recyclable products, and ozone-free products. Empirical analysis divulged that product quality followed by corporate image, store image, and product price jointly affected customer satisfaction in using green products. They are highly concerned that the green store provides a variety of good quality products with good value for money. Marketers should aggressively promote the identification of green products and overcome the problem of just noticeable difference between green product and non-green product among consumers for business sustainability. Empirical findings provide valuable insights to put forth in outlining effective marketing strategies that widen the marketers’ understanding of consumer behaviour in using green products with regard to their satisfaction and loyalty levels from the perspective of product quality, corporate image, store image, and product prices in Malaysia markets.  相似文献   
897.
Scientific consensus shows that the changes related to climate change are already occurring and will intensify in the future. This will likely result in significant alterations to coastal ecosystems such as mangroves, increase coastal hazards and affect lifestyles of coastal communities. There is increasing speculation that mangrove, a socio-economically important ecosystem, will become more fragile and sensitive to uncertain climate variability such as sea level rise. As a result, mangrove-dependent societies may find themselves trapped in a downward spiral of ecological degradation in terms of their livelihoods and life security. Strengthening the resilience capacity of coastal communities to help them cope with this additional threat from climate change and to ensure sustainability calls for immediate action. In this context, this paper critically examines the regional implications of expected sea level rise and threats to mangrove-dependent communities through a case study approach. The main objective is to highlight the requirement for climate change communication and education to impart information that will fulfil three expectations: (1) confer understanding; (2) assess local inference on climate change through a participatory approach; and (3) construct a framework for climate change awareness among mangrove-dependent communities through community-based non-formal climate change education. This scale of approach is attracting increasing attention from policymakers to achieve climate change adaptation and derive policies from a social perspective.  相似文献   
898.
This paper considers the way freshwater resources are perceived in an era of climate change. It is suggested that in many parts of the world water is moving from being a renewable resource (or continuous natural resource) to a potentially renewable resource (PRR). In some areas water is moving from being a PRR to a nonrenewable resource. Selected water problems from three continents are investigated in the context of this theoretical construct. Recent experience in the United Kingdom is then also investigated as a case study of these changes before brief conclusions are drawn.  相似文献   
899.
以淮河南岸最大支流——淠河流域为研究区域,采用嵌套入ArcGIS软件的SWAT分布式机理性水文模型定量评估土地利用变化对降水-径流关系的影响.结果表明,1996-2010年淠河流域的土地利用变化主要表现为水田、旱地向建设用地转化以及林地向园地转化.相较于1996年的土地利用情景,2010年土地利用情景下的多年平均径流增加5.87%,年径流的增加主要表现为汛期径流增加,非汛期径流则呈减少趋势,径流量年内变幅加大.对于不同水文年份而言,平水年对土地利用变化的水文响应最明显,变幅最大,枯水年则略大于丰水年,淠河流域的水源涵养能力呈现减退趋势.  相似文献   
900.
淮河中上游参考作物腾发量趋势变化及其成因   总被引:1,自引:0,他引:1  
参考作物腾发量(ET0)是由平均气温(Tm)、实际水汽压(ea)、风速(u2)和净辐射(Rn)等多个气候要素驱动的,因此,气候变化对ET0的影响是显而易见的。分析ET0和各气候要素的时空变化特征可以获得气候变化对ET0的影响。利用Mann-Kendall(MK)检验分析了淮河中上游流域1959—2009年ET0及各气候要素的变化趋势。并且利用偏相关分析和贡献分析获得ET0和主要气候要素之间的定性和定量关系。结果显示,大部分站点的年ET0表现出显著的下降趋势。在夏季,所有站点的ET0都表现出显著的下降趋势,且西北部地区尤其显著。其他3个季节显著下降的ET0趋势主要分布在淮河中上游流域的西北部地区。年及夏季的ET0在1970年以后表现出下降的趋势并且在1975年以后变的显著,其余3个季节ET0并无明显变化特征,说明夏季ET0的显著减少是年ET0显著减少的主要原因;实际水汽压与ET0之间表现出显著的负相关关系,而平均温度、净辐射和风速则表现出显著的正相关关系;无论从定性的偏相关关系还是定量的贡献分析都可看出虽然年及四季的平均气温是显著上升的,并且导致了ET0的增加,但是整个流域显著下降的风速和净辐射直接导致了年及夏季ET0的显著减少。  相似文献   
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