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1.
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   

2.
SUMMARY

Numbers of sika deer (Ceruus nippon), resident in the Dilijan Reserve in 1969 (52 animals), 1970 (50), 1972 (1), and 1976 (28) dramatically increased in number until 1981, when the population reached a ceiling, being the number which can subsist in the area—300 individuals (density—11–12.5 deer per 1000 ha). Thus, Dilijan Reserve's C. nippon population develops in a way which resembles an S-like log curve equation.

Actually, Dilijan Reserve no longer has the status of a protected area—nowadays lumbering activities predominate and, inevitably, the unique broadleaf deciduous forest ecosystem will run down to extinction. Such economically valuable species as oak, beech, and sika deer are likely to be the first victims of this large-scale devastation.

The present article does not reject exploitation of any resource (including sika deer), if necessary. The key question is: how C. nippon can be sustainably utilized, so that the number of culled animals is replenished within the same year and and so that eventually the population size will remain constant?  相似文献   

3.
The understanding of population structure and gene flow of marine pelagic species is paramount to monitoring, management and conservation studies. Such studies are often hampered by the potentially high dispersal behavior of the species, the lack of obvious geographical barriers in the marine environment and the scarce sample availability. Short-beaked common dolphins (Delphinus delphis) are widespread in coastal and open-ocean habitats of the North Atlantic Ocean, nevertheless population structure and migratory patterns are poorly understood. Furthermore, concern has been raised about the status of the species because large numbers of dolphins have been taken incidentally in several fisheries throughout the North Atlantic in the past decades. In the present study, a large number of individual samples were obtained from seasonal and spatial aggregations of common dolphins from western (wNA) and eastern North Atlantic (eNA) regions, mostly using opportunistic sampling (i.e. from incidental entanglement in fishing gear or beach-cast carcasses). Genetic variability was investigated using nuclear (14 microsatellite loci) and mitochondrial (360 bp of the control region) genetic markers. Levels of genetic diversity were relatively high in all sampled areas and no evidence of recent reduction of effective population size (i.e. bottleneck) was detected at the nuclear loci. Significant population structure was detected between the two main regions (wNA and eNA) where it appeared to be more pronounced at mitochondrial (F ST = 0.018, P < 0.001) than nuclear markers (F ST = 0.005, P < 0.05), indicating the presence of at least two genetically distinct populations of common dolphins in the North Atlantic Ocean. In contrast, no significant genetic structure was detected between temporal aggregations of dolphins from within the same region, suggesting possible seasonal movement patterns at a regional scale. The observed levels of genetic differentiation between classes of markers are discussed here as a possible consequence of migratory patterns or recent population subdivision. An erratum to this article can be found at  相似文献   

4.
The Great Barrier Reef (GBR) exhibits distinct cross-shelf zonation. These patterns are particularly well documented in reef fishes and have been attributed to either environmental gradients (e.g. wave energy, oceanography) or barriers to gene flow. This study examined the extent to which barriers to gene flow contribute to cross-shelf patterns by examining the mitochondrial DNA of gobies (genus Eviota). The genus Eviota was selected due to its extreme life history characteristics (shortest vertebrate lifespan) and cross-shelf distribution patterns (E. queenslandica, inner- and mid-shelf, and E. albolineata mid- and outer-shelf). Although cross-shelf barriers to gene flow were predicted, this study found no population structure between shelf locations. However, a genetically distinct population of E. queenslandica (the inner-shelf species) was observed at North Direction Island (Phist = 0.088, P = 0.004). As no comparable structure was observed in E. albolineata (the outer-shelf species) it may be that habitat type (E. queenslandica = reef lagoon, E. albolineata = reef crest) is a significant factor driving the structure observed in E. queenslandica. Larval behaviour, olfactory or auditory senses and reef selection at settlement could be assisting larvae to return to reefs similar to natal reefs. We suggest that ecological gradients are more important than barriers to gene flow in structuring cross-shelf distributions within Eviota.  相似文献   

5.
SUMMARY

The Rio Earth Summit and publication and distribution of Agenda 21 (UN, 1992) have generated much activity in many nations towards development and implementation of community indicators of sustainable development (SI). In recent years efforts at development and implementation of SI have intensified at regional and urban government levels, although fewer efforts are evident at a rural community level. In response to initial ad hoc efforts, methodologies for SI construction are currently being proposed, tested and refined. Within this evolutionary process, increasing recognition is being given to the critical need for, and importance of, ‘stakeholder’ involvement in SI development and implementation. This paper critically reviews these and related efforts from the perspective of rural communities in Canada. The argument is presented that the process of development and implementation of rural community-level SI can significantly benefit from development and implementation of a methodological approach in support of principles and practices of effective stakeholder involvement. It is further argued that development of SI must be stakeholder-driven, and that a pivotal element in the SI development process is the facilitation of information sharing. The paper concludes with a proposal for an approach to stakeholder participation and information sharing achieved through research, testing and refinement, and integration of these concepts within the process of rural community sustainable indicator development.  相似文献   

6.
Determining the magnitude of homing behaviour within migratory fish species is essential for their conservation and management. We tested for population genetic structuring in the anadromous alosines, Alosa alosa and A. fallax fallax, to establish fidelity of stocks to spawning grounds in the United Kingdom and Ireland. Considerable genetic differences were present among populations of both species, suggesting strong fidelity to breeding grounds and compatible with homing to natal origins. Moreover, the genetic structure of A. fallax fallax showed a clear pattern of isolation-by-distance, consistent with breeding populations exchanging migrants primarily with neighbouring populations. Spatial genetic differences were on average much greater than temporal differences, indicating relatively stable genetic structure. Comparing anadromous A. fallax fallax populations to the landlocked Killarney shad subspecies, A. fallax killarnensis (Ireland), demonstrated a long history of separation. These results demonstrating regional stock structure within the British Isles will inform practical management of stocks and their spawning habitats.  相似文献   

7.
SUMMARY

This paper examines how remote-sensing data and regional social and economic data can be used together to identify changes in land-use patterns in particular regions. Study of the spatiotemporal dynamics of remote-sensing data can identify trends in competing uses of land, water and other natural resources for agriculture, industrial development and urban settlements. When combined with information on trends in industrial production, population, agricultural production, pollutant releases, water usage and natural forest coverage, these data reveal patterns of anthropogenic disturbance that can provide early signals of problems in resource decline or land-use management. This study focuses on land-cover changes in southern Jiangsu Province of the People's Republic of China between 1976 and 1984. This region, to the west of Shanghai and to the south of the Yangtze River, experienced unprecedented economic growth after the end of the Cultural Revolution. Remote-sensing imagery reveals the rapid growth of urban centres, commensurate declines in surface water area, and changing patterns of agriculture. The observed changes cast doubt on the ability of the region to sustain such rapid and intense land-use conflicts over a long period.  相似文献   

8.
9.
Groundwater quality which relates closely to human health has become as important as its quantity due to the demand for safe water. In the present study, an entropy-weighted fuzzy water quality index (WQI) has been proposed for performing groundwater quality assessment in and around an industrial park, northwest China, where domestic water requirements are solely met by groundwater. The human health risk was assessed with the model recommended by the United States Environmental Protection Agency. In addition, the sources of major ions and main contaminants were also analyzed. The study shows that groundwater in the study area has been contaminated conjunctively by natural processes and industrial and agricultural activities. Nitrate, manganese (Mn), fluoride, total dissolved solids, total hardness and sulfate are major contaminants influencing groundwater quality. Nitrate and heavy metals such as Mn are mainly affected by human agricultural activities and industrial production, while other contaminants are mainly originated from mineral weathering and water–rock interactions. The results of water quality assessment suggest that half of the groundwater samples collected are of medium quality thus require pretreatment before human consumption. The mean health risk caused by the consumption of contaminated groundwater in the area is 8.42 × 10?5 per year which surpasses the maximum acceptable level (5 × 10?5 per year) recommended by the International Commission on Radiologic Protection. The entropy-weighted fuzzy WQI proposed in this study can not only assign proper weights to parameters but also treat uncertainties associated with water quality classification. This study will be of interest to international environmentalists and hydrogeologists. It will also be useful in regional groundwater management and protection.  相似文献   

10.
Silica nanoparticles are increasingly used in industrial, cosmetics, and medical applications. Workers in nanosilica production industries, laboratory personnel in drug production industries, patients taking drugs with nanosilica in its formulations, and everyone in society who uses cosmetics are potentially at risk to health effects induced by silica nanoparticles. Like other nanomaterials, nanosilica has unique physical and chemical properties that modify its toxic effects compared to bulk silica or microparticles of silica. Nanosilica toxicology has been studied by various in vitro and in vivo protocols and on humans, studies which are collected and summarized in the present publication. The toxic effects are outlined based on the type of body compartment, viz. cardiovascular, dermal, respiratory, neural, hepatic, genetic, immune, reproductive, and renal system. Further information, especially the experimental protocols and toxicological endpoints, are summarized in tables.  相似文献   

11.
During the last years, molecular studies revealed significant population differentiation and cryptic species within various benthic and pelagic marine Antarctic taxa. This is unexpected due to the lack of obvious barriers to gene flow and strong current systems. Using mitochondrial (COI, 16S rDNA) and nuclear (28S rDNA: D2) gene fragments, we tested whether two circum-Antarctic benthic shrimps with planktotrophic larvae, Chorismus antarcticus and Nematocarcinus lanceopes, show patterns of regional differentiation. For both species, the 16S and the 28S fragment were invariant. However, for COI we found 24 different haplotypes for Chorismus antarcticus and 54 for Nematocarcinus lanceopes. No significant differentiation was observed among populations or regions. Furthermore, we found signatures of a population expansion in the late Pleistocene hinting at an impact of large-scale glaciations in particular on the shallow-water shrimp Chorismus antarcticus, supporting a (re)colonization and demographic expansion of this shrimp species in response to climate oscillation.  相似文献   

12.
Abstract: Conservation researchers are increasingly aware of the need to conduct interdisciplinary research and to engage nonscientists in practical applications of conservation biology. But so far, industrial designers have been left out of such collaboration and outreach efforts. Conservation of wildlife often depends on products such as nest boxes, feeders, barriers, and corridors, all of which have a designed component that is frequently overlooked. Furthermore, many products are adopted without testing on short or long time scales. We argue that the design of products for conservation, and hence their functionality, effectiveness, and value, can be improved through collaboration with industrial designers. We see four key benefits that can arise from interactions with industrial designers: improvement of product quality and value, innovation and improvement in functionality of products, harmonization of conservation products with local values, and development of a psychological biomimesis approach to design. The role of industrial designers in conservation projects would be to improve factors such as product durability, affordability, functionality, and aesthetic appeal to local people. Designers can also help to create multiple product options whose success can be tested in the field. We propose that collaborations with industrial designers can contribute to the development of improvements to existing products and innovations in the practice of animal conservation.  相似文献   

13.
Abstract: The search for generalities in ecology has often been thwarted by contingency and ecological complexity that limit the development of predictive rules. We present a set of concepts that we believe succinctly expresses some of the fundamental ideas in conservation biology. (1) Successful conservation management requires explicit goals and objectives. (2) The overall goal of biodiversity management will usually be to maintain or restore biodiversity, not to maximize species richness. (3) A holistic approach is needed to solve conservation problems. (4) Diverse approaches to management can provide diverse environmental conditions and mitigate risk. (5) Using nature's template is important for guiding conservation management, but it is not a panacea. (6) Focusing on causes not symptoms enhances efficacy and efficiency of conservation actions. (7) Every species and ecosystem is unique, to some degree. (8) Threshold responses are important but not ubiquitous. (9) Multiple stressors often exert critical effects on species and ecosystems. (10) Human values are variable and dynamic and significantly shape conservation efforts. We believe most conservation biologists will broadly agree these concepts are important. That said, an important part of the maturation of conservation biology as a discipline is constructive debate about additional or alternative concepts to those we have proposed here. Therefore, we have established a web‐based, online process for further discussion of the concepts outlined in this paper and developing additional ones.  相似文献   

14.
Knowledge co‐production and boundary work offer planners a new frame for critically designing a social process that fosters collaborative implementation of resulting plans. Knowledge co‐production involves stakeholders from diverse knowledge systems working iteratively toward common vision and action. Boundary work is a means of creating permeable knowledge boundaries that satisfy the needs of multiple social groups while guarding the functional integrity of contributing knowledge systems. Resulting products are boundary objects of mutual interest that maintain coherence across all knowledge boundaries. We examined how knowledge co‐production and boundary work can bridge the gap between planning and implementation and promote cross‐sectoral cooperation. We applied these concepts to well‐established stages in regional conservation planning within a national scale conservation planning project aimed at identifying areas for conserving rivers and wetlands of South Africa and developing an institutional environment for promoting their conservation. Knowledge co‐production occurred iteratively over 4 years in interactive stake‐holder workshops that included co‐development of national freshwater conservation goals and spatial data on freshwater biodiversity and local conservation feasibility; translation of goals into quantitative inputs that were used in Marxan to select draft priority conservation areas; review of draft priority areas; and packaging of resulting map products into an atlas and implementation manual to promote application of the priority area maps in 37 different decision‐making contexts. Knowledge co‐production stimulated dialogue and negotiation and built capacity for multi‐scale implementation beyond the project. The resulting maps and information integrated diverse knowledge types of over 450 stakeholders and represented >1000 years of collective experience. The maps provided a consistent national source of information on priority conservation areas for rivers and wetlands and have been applied in 25 of the 37 use contexts since their launch just over 3 years ago. When framed as a knowledge co‐production process supported by boundary work, regional conservation plans can be developed into valuable boundary objects that offer a tangible tool for multi‐agency cooperation around conservation. Our work provides practical guidance for promoting uptake of conservation science and contributes to an evidence base on how conservation efforts can be improved.  相似文献   

15.
农村产业结构调整问题研究   总被引:2,自引:0,他引:2  
本文首先对农村产业结构调整的相关概念进行了阐述.其次,分析和归纳了判断农村产业结构合理化的标准以及农村产业结构变动的影响因素.  相似文献   

16.
The depletion of shallow-water fish stocks through overexploitation has led to increasing fishing pressure on deep-sea species. Poor knowledge of the biology of commercially valuable deep-water fish has led to the serial depletion of stocks of several species across the world. Data regarding the genetic structure of deep-sea fish populations is important in determining the impact of overfishing on the overall genetic variability of species and can be used to estimate the likelihood of recolonisation of damaged populations through immigration of individuals from distant localities. Here the genetic structure of the commercially fished deep-water species the blackspot sea bream, Pagellus bogaraveo is investigated in the northeastern Atlantic using partial DNA sequencing of mitochondrial cytochrome b (cyt-b) and D-loop regions and genotyping of microsatellite loci. An absence of variation in cyt-b and low genetic variation in D-loop sequences potentially indicate that P. bogaraveo may have undergone a severe bottleneck in the past. Similar bottlenecks have been detected in other Atlantic species of fish and have possibly originated from the last glaciation. P. bogaraveo may have been particularly vulnerable to the effects of low temperature and a fall in sea level because stages of its life history occur in shallow water and coastal sites. However, there are other explanations of low genetic variability in populations of P. bogaraveo, such as a low population size and the impacts of fishing on population structure. Analysis of population structure using both D-loop and microsatellite analysis indicates low to moderate, but significant, genetic differentiation between populations at a regional level. This study supports studies on other deep-sea fish species that indicate that hydrographic or topographic barriers prevent dispersal of adults and/or larvae between populations at regional and oceanographic scales. The implications for the management and conservation of deep-sea fish populations are discussed.Communicated by J.P. Thorpe, Port Erin  相似文献   

17.
SUMMARY

The structure, conduct and performance, and the environmental impacts of the chainsaw lumber production sector in Guyana are investigated. Chainsaws are a highly mobile lumber technology that is used to rip or produce lumber within the forest. Chainsaw lumbering operations have become the dominant lumber producer for the domestic market. Production costs are only 53% of wholesale lumber prices. On a ms basis, chainsaw operations' net profit is 80% of the gross price paid for logs at sawmills and more than twice the profit of firms engaged in the harvesting and transportation of logs to sawmills. Sawmills recognize this cost advantage and are increasingly using chainsaws in the production of lumber.

The handling and transportation of chainsawn lumber within the forest is environmentally less damaging than log production. The log recovery rate is 10–15% for chainsaw operations, as compared to the sawmill average of 40–45%. Log residue from chainsaw operations is left within the forest which promotes faster forest regrowth, while that at sawmills is wasted. Chainsaw operations harvest immature trees, engage in the harvesting of selective species, over-harvest trees per unit area of land, and engage in frequent reentry of the forest. Because of these practices, the chainsaw lumber sector is not environmentally sustainable and will require regulation. Policies that follow a non-market solution will be required in regulation.  相似文献   

18.
ABSTRACT

The present research aimed to determine the lowest levels of three heavy metals (Pb, Cd and Cu) to which the larvae of Southern House Mosquito, Culex quinquefasciatus are susceptible in water. The study also aimed to investigate the effects of these heavy metals on the development of Cx. quinquefasciatus at concentrations set by Pakistan Environmental Protection Agency (Pak-EPA) as permissible levels for liquid industrial effluents. The 2nd instar larvae of Cx. quinquefasciatus were exposed to different concentrations of Pb, Cd and Cu and their effects on oviposition preference, egg hatching rate and larval development were studied. The LC50 values of Pb, Cd and Cu were 12.6, 6.3 and 2.6?ppm, respectively. Gravid female mosquito adults deposited a significantly lower number of egg rafts in containers containing 0.50?ppm Pb or 1.0?ppm Cu in water. Each of the heavy metals in water resulted in significantly (p?<?0.05) lower egg hatching rate, prolonged time to pupation, lower pupation rate, prolonged time to adult emergence, lower adult emergence rate and higher female to male ratio. It is concluded that the 2nd instar larvae of Cx. quinquefasciatus are susceptible to Pak-EPA permissible levels of Pb, Cd and Cu in municipal and liquid industrial effluents.  相似文献   

19.
Ammophila arenaria (marram grass) was introduced to South Africa from Europe as a means of stabilizing the Cape Flats in the 1870s, but was only successfully established in the 1890s as it was found that seeds from the first introductions did not readily germinate. By the end of the last century, it was successfully used as a dune stabilizing grass. It is now widely used in stabilization projects along the Cape coastline, being established by planting cuttings or whole plants. Because of problems experienced of marram becoming invasive, especially on the west coast of North America, and the fact that we have many invasive species which threaten our indigenous dune fields, studies have been initiated on this plant in South Africa. Most work to date has involved investigating the methods used to establish the plant in stabilization sites, and very little has been done on the biology of the species in this country. Marram is generally thought not to seed in South Africa, and thus its spread has been limited. However, in the light of recent reports of successful germination of the seed, detailed studies on the phenology of seed production and establishment in natural areas will be undertaken. Studies on the natural control by fungal species and nematodes will be carried out in conjunction with work done in the Netherlands, so that a comparison of the biology of the species in South Africa can be made with that in Europe, where it is used extensively to stabilize dunes. Nomenclature: Arnold & de Wet (1993) for vascular plants.  相似文献   

20.
This paper illustrates a method based on local likelihood (LL) for detecting disease clusters. The approach is based on estimating a lasso distance for each region: within which regions are considered to be clustered. An important advantage in implementing this approach is that it does not require any special Monte Carlo Markov Chain (MCMC) algorithm, e.g., reversible jump MCMC, which is essential in hidden Markov model approach. Another advantage is that extending the model to incorporate covariates is straightforward. We illustrate three ways of doing this by using Eastern Germany lip cancer data. By using simulated data, we have made a comparison with the BYM model [Besag et al. (1991) Annals of the Institute of Statistical Mathematics, 43, 1–59] and the mixture model [Lawson and Clark (2002) Disease Mapping and Risk Assessment for Public Health, Chapman and Hall]. We also did a limited examination of the ability of the LL model to recover true relative risk under different priors for lasso parameter. In order to check the edge effects, which has been overlooked in many spatial clustering models for disease mapping but deserves special attention as it lacks observable neighbors, we have adapted here a simple approach to observe the changes in relative risks when the edge regions are omitted. An erratum to this article is available at .  相似文献   

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