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1.
In the process of rapid urbanisation in China, environmental problems have increased, from sewage discharge to climate change. Marine protected areas (MPAs) are widely advocated as a means to comprehensively manage human activities and resources in ocean and coastal areas. However, MPAs only safeguard populations or assemblages within their boundaries and fail to offer any protection from many major threats to marine environments. An increase in environmental threats implies an increase in environmental management and assessment. We propose a methodological framework for integrated ecological assessment using the Xiamen marine protected area as a case study. The integrated ecological assessment framework can be generalised from the dimensions of environment, economy, society and institution. Surveys were undertaken to assess the state of the Xiamen coastal environment, the resources of the reserve, and issues associated with human activities. Stakeholders were interviewed about their attitudes towards issues regarding the management of the reserve. The constraints of the reserve management were identified. The methodological framework is presented as a tool to help identify relative ecological security in order to prioritise actions and assess the ecological implications of management and policy decisions.  相似文献   

2.
Techniques for water harvesting from streams for irrigation and waterpower utilities, particularly in the semi-arid middle mountain region of Nepal, were developed many centuries ago. Water harvesting techniques have traditionally evolved to fit the local environment and living conditions of the people. In terms of community participation, the sustainability of community-based local water resources management in Nepal should promote traditional streamwater harvesting technologies that will potentially benefit local communities and also should be recognized by environmentalists and water experts. This paper investigates some traditional forms of water delivery technologies adopted by local farmers in three catchment areas from the middle mountain region of Nepal. Each form of indigenous practice is considered from the objective of scientific validation.  相似文献   

3.
In the context of ongoing theoretical debate on the role of group size and heterogeneity in affecting collective action outcomes, this study analyzed associations of group size, and intra-group heterogeneities arising from ethnic, educational and livelihood-related differences with conditions of selected forests managed (formally or informally) by local user groups in the middle hills of Nepal. Four biological variables, basal area of trees, density of trees, density of saplings and richness of plant species, were chosen to represent the condition of the forests. The findings show significant differences in biological condition of the forests managed by different size forest user groups and levels of ethnic, educational and livelihood-related heterogeneities. These differences, however, are inconsistent across the dependent variables representing forest condition, indicating that they were not necessarily caused by the size of the user groups or the group heterogeneities, but could be the result of other factors, such as the history of forest land use and degradation, composition of tree species and institutional arrangements governing the forests.  相似文献   

4.
The participatory approach in management of forests is now well established in forest policies of many developing countries. Incentives for different groups to participate have been argued by many to be desirable characteristics to promote participation. A key challenge for government and donor agencies is to develop better understanding of the incentives for different groups to be able to achieve and sustain their participation. Based on a case study of a joint forest management (JFM) programme in the northern state of Haryana in India, this paper highlights the relevance of understanding people's perception of the incentives. It specifically examines three hypotheses related to perceptions of villagers about incentives offered under the JFM programme and relates them to their participation in joint management. It concludes that a better understanding is likely to help in improving project implementation at the local level and the design of participatory forest management programmes more generally.  相似文献   

5.
Socio-economic development of mankind and well-being depend on the environment and the way in which development influences the environment. Thus, environment and development are interdependent. In fact, economic development is closely linked with the development of resources. These resources can be classified into three categories: public goods, semi-public goods (also known as common property resources) and private goods. In poor countries common property resources make a valuable contribution to the sustainable livelihoods of rural populations. The impact of globalisation on the commons shows various patterns of ownership, control, use and misuse. The commons were subjected to degradation as well as conservation in the process of centralized management in India. After the reform period, the administration of natural resources was given significant attention by specialized departments such as the Forest Department and the Revenue Department. All the land, apart from private land, was regarded as state property and controlled by the state. This paper highlights the need to examine the common property resources sector in the context of wider economic policy reform processes in the Indian economy.  相似文献   

6.
There are always conflicts between the need for conservation and economic growth in the developing countries. Planning plays a primary role in balancing these conflicts. This is particularly obvious in Chinese cities since China adopted its open door policy in 1978. Foreign investment has been a major driving force for rapid growth of the Chinese economy. Planners in China have been facing the dilemma of protecting the natural environment on the one hand while, on the other hand, supporting the overall national goal of attracting foreign investment to maintain continuous economic growth. The planning system in China, which has been largely based on a planned economy, soon found itself handicapped in safeguarding the environment from rapid industrialization and urbanization fostered by market forces. This paper takes Guangzhou as an example to study challenges to the planning system in Chinese cities in the past two decades of rapid economic growth and urbanization. By means of a case study on an industrial development within a protected orchard area in Guangzhou, this study illustrates the conflict between the need for rural conservation and the pressure for economic development in the Chinese cities. In particular, it analyzes the pressures on the present urban planning system in China in terms of the following categories: the emergence of private investors in urban development; the goal of pursuing a high economic growth rate; the implications of a transitional economy for urban planning; and the weakness of the present urban planning system. It concludes that the role of urban planning in China should change from simply providing guidelines on board land-use strategy, to a combination of a strategic plan with specific development control laws at the operational level. Finally, some recommendations are suggested as to how to improve the planning system in China.  相似文献   

7.
The objective of this study was to elicit community perceptions on the effectiveness of the CAMPFIRE programme, a community initiative, designed to benefit rural communities in Gonono ward in the Zambezi valley. Five villages and 76 respondents were selected from the ward using simple random sampling. Data collection included a structured questionnaire administered to households, semi-structured interviews with key informants, such as chiefs, headmen and local council staff, transect walks and participant observations. The results of the study revealed that, although the CAMPFIRE concept has been instrumental in creation of employment and infrastructure, the local community considers that no significant changes have occurred to their livelihoods. The findings suggest that the current model of wildlife conservation in Zimbabwe is not promoting total community participation. Future models need to focus on total involvement and independence from government structures. However, this can only happen when there is sufficient capacity building in communities on a wide number of issues, including general management, to ensure long-term sustainability.  相似文献   

8.
This paper on Low External Input Agriculture (LEIA) has explored how indigenous hill farming systems in a developing country setting of rural Nepal are functioning and which ecological properties of such systems could contribute to the development of Low External Input and Sustainable Agriculture (LEISA). Three cases were studied using direct field observation, group discussion and interviews, and the important practices of LEIA were ranked into eight classes to analyse the ecological sustainability of the hill farming systems. The study shows that the hill farming system is complex, diverse, heavily reliant on local resources and focuses on the renewability of production resources within the farm. All this can greatly contribute to make the system ecologically sustainable. However, demands for increased production put considerable pressure on farmers to apply external inputs which, if in excess, may jeopardise the whole system. A prerequisite for guidance in careful soil management is the strengthening of supportive research aimed at teaching farmers how to use external inputs. This must agree with the principles of sustainable agriculture and take into account the site-specific variations which are characteristic of Nepalese hill farming systems. We defined the term Ecological Dynamics as 'the pattern of changes in structure and/or forces in processes which govern the development of natural and artificial ecosystems'. This definition assists in identification of trends in ecological sustainability. Understanding indigenous farming systems reveals important ecological clues essential for the development of sustainable agriculture.  相似文献   

9.
Based on a survey of 107 farm households by means of participatory rural appraisal, this paper presents a region-level analysis of farmer's perception and response towards land policies and eco-environment in the Loess hilly area, China. The surveyed farmers are divided into two groups, farmers on non-irrigated farmland and farmers on irrigated farmland. The results indicate that most farmers mainly depend on cropland, especially the farmers on non-irrigated farmland. Farmers believe that stability and persistence of land policies are important, and most hold a positive attitude towards the Grain-for-Green Programme. The farmers on irrigated farmland have a more favourable attitude to environmental conservation than the farmers of non-irrigated farmland. Nearly 80% of interviewees consider that the local eco-environment has improved in the last ten years. About 45% never consider the environmental impact of their agriculture practices. About 55% think drought is the most important reason for eco-environment deterioration, overgrazing and serious soil erosion. Soil and water conservation is not conscious and voluntary behaviour for farmers, it is only a measure to guarantee their basic agricultural production and to improve their living conditions. Results indicate that farmers on nonirrigated land find engineering approaches more beneficial to agronomic methods. However, the farmers on irrigated farmland pay more attention to improving farmland quality.  相似文献   

10.
An attempt was made for a comparative study of the mesozooplankton communities between the Aegean and Black Seas. These areas are in connected through the Sea of Marmara, the Bosporus and the Dardanelles straits. The comparison was mainly based on data collected both in coastal and offshore waters, by the Hellenic Centre for Marine Research (Greece), the Shirshov Institute of Oceanology (Russia), the Institute of Biology of Southern Seas (Ukraine) and the Institute of Oceanology (Bulgaria). Our data revealed important differentiation in terms of species composition and interannual fluctuations of zooplankton quantity. Among the common copepod species, those presenting an eurytherm and/or euryhaline character (e.g. Acartia clausi, Paracalanus parvus, Penilia avirostris, Podon polyphemoides) were found dominant in the Black Sea and common in the Aegean Sea. Decreased dissimilarity of species composition seems to exist between the North Aegean Sea and the Black Sea, as well as between the coastal areas of the Black Sea and those affected by pollution in the Aegean Sea. A common feature of both seas is the existence of spatial differentiation in terms of the quantity of zooplankters due to anthropogenic and/or natural influences. The pattern of this differentiation seems to vary interannually in the Black Sea, depending either on the abundance of mesozooplankton predators (indigenous or invasive species) or on global climatic changes. Although the Black Sea is generally richer in zooplankton than the Aegean Sea, the significant decrease in the quantity of zooplankton from the early 1980s to the mid-1990s, due to the above factors, resulted in quasi-similar values in both areas. Black Sea mesozooplankton has revealed strong interannual variability both quantitatively and qualitatively, whereas no significant variability was detected in the Aegean Sea. This difference could be attributed both to variant anthropogenic forcing on these ecosystems and to the sensitive character of the semi-enclosed Black Sea.Communicated by M.E. Vinogradov, Moscow  相似文献   

11.
The crop livestock integrated farming system practiced in hilly regions of developing countries largely depends on the ecosystem as a whole. More especifically, the livestock component of the farming system relies heavily on natural resources such as forest, grazing and agricultural land for the supply of feed and fodder. The importance of animals as agents of nutrient recycling, sources of rural energy in terms of draft power and fuel, as well as being major contributors to the farm economy, has resulted in an increased population of ruminants in these regions, creating a threat to the sustainability and productivity of these land resources. This paper is an attempt to evaluate the livestock carrying capacity of land resources and to formulate the optimum herd size compatible with the differently resourced farm categories within the sub-watershed region of the mid-hills in Nepal. Our analysis reveals that the livestock carrying capacity of the land resources at the watershed level is 11696 Livestock Units (LU), whereas current stocking is 12985 LU, suggesting an overstocking of 1289 LU at the watershed level. Total feed supply from different sources is 12668 mt/yr whereas current Total Digestive Nutrient (TDN) demand is 14060 mt/yr, a negative balance of 1393 mt/yr. The excess livestock at the sub-watershed level directly implies excess livestock holding, producing a poor nutritional status for the farm household. Linear programming analysis reveals that the farmers of large, medium and small category farms can optimize their livestock holding by a combination of 3 LU buffaloes and 4 LU goats, 2 LU buffaloes and 4 LU goats and 1 LU buffaloes and 4.4 LU goats, thus giving maximum return to the farm family without exerting pressure on fragile natural resources.  相似文献   

12.
Malaria and risk of predation: a comparative study of birds   总被引:5,自引:0,他引:5  
Møller AP  Nielsen JT 《Ecology》2007,88(4):871-881
Predators have been hypothesized to prey on individuals in a poor state of health, although this hypothesis has only rarely been examined. We used extensive data on prey abundance and availability from two long-term studies of the European Sparrowhawk (Accipiter nisus) and the Eurasian Goshawk (Accipiter gentilis) to quantify the relationship between predation risk of different prey species and infection with malaria and other protozoan blood parasites. Using a total of 31 745 prey individuals of 65 species of birds from 1709 nests during 1977-1997 for the Sparrowhawk and a total of 21 818 prey individuals of 76 species of birds from 1480 nests for the Goshawk during 1977-2004, we show that prey species with a high prevalence of blood parasites had higher risks of predation than species with a low prevalence. That was also the case when a number of confounding variables of prey species, such as body mass, breeding sociality, sexual dichromatism, and similarity among species in risk of predation due to common descent, were controlled in comparative analyses of standardized linear contrasts. Prevalence of the genera Haemoproteus, Leucocytozoon, Plasmodium, and Trypanosoma were correlated with each other, and we partitioned out the independent effects of different protozoan genera on predation risk in comparative analyses. Prevalence of Haemoproteus, Leucocytozoon, and Plasmodium accounted for interspecific variation in predation risk for the two raptors. These findings suggest that predation is an important factor affecting parasite-host dynamics because predators tend to prey on hosts that are more likely to be infected, thereby reducing the transmission success of parasites. Furthermore, this study demonstrates that protozoan infections are a common cause of death for hosts mediated by increased risk of predation.  相似文献   

13.
Social amoebae aggregate to form a multicellular slug that migrates some distance. Most species produce a stalk during migration, but some do not. We show that Dictyostelium giganteum, a species that produces stalk during migration, is able to traverse small gaps and utilize bacterial resources following gap traversal by shedding live cells. In contrast, we found that Dictyostelium discoideum, a species that does not produce stalk during migration, can traverse gaps only when in the presence of other species’ stalks or other thin filaments. These findings suggest that production of stalk during migration allows traversal of gaps that commonly occurs in soil and leaf litter. Considering the functional consequences of a stalked migration may be important for explaining the evolutionary maintenance or loss of a stalked migration.  相似文献   

14.
Parasites are ubiquitous in populations of free-ranging animals and impact host fitness, but virtually nothing is known about the factors that influence patterns of disease risk across species and the effectiveness of behavioral defenses to reduce this risk. We investigated the correlates of malaria infection (prevalence) in Neotropical primates using data from the literature, focusing on host traits involving group size, body mass, and sleeping behavior. Malaria is spread to these monkeys through anopheline mosquitoes that search for hosts at night using olfactory cues. In comparative tests that used two different phylogenetic trees, we confirmed that malaria prevalence increases with group size in Neotropical primates, as suggested by a previous non-phylogenetic analysis. These results are consistent with the hypothesis that larger groups experience increased risk of attack by mosquitoes, and counter to the hypothesis that primates benefit from the encounter-dilution effect of avoiding actively-seeking insects by living in larger groups. In contrast to non-phylogenetic tests, body mass was significant in fewer phylogeny-based analyses, and primarily when group size was included as a covariate. We also found statistical support for the hypothesis that sleeping in closed microhabitats, such as tree holes or tangles of vegetation, reduces the risk of malaria infection by containing the host cues used by mosquitoes to locate hosts. Due to the small number of evolutionary transitions in sleeping behavior in this group of primates, however, this result is considered preliminary until repeated with a larger sample size. In summary, risk of infection with malaria and other vector-borne diseases are likely to act as a cost of living in groups, rather than a benefit, and sleeping site selection may provide benefits by reducing rates of attack by malaria vectors.Electronic Supplementary Material Supplementary material is available in the online version of this article at and is accessible for authorized users.  相似文献   

15.
Cooperatively breeding birds might be expected to suffer from higher costs of parasitism than pair-breeding species because of two aspects of their ecology which should facilitate horizontal transmission and possibly select for higher parasite virulence: first, they interact regularly with more individuals than pair-breeding species, and second, these individuals are commonly close relatives that could share similar resistance alleles. This hypothesis predicts that cooperative breeders should invest relatively more in immune defence than closely related species which breed in pairs. I tested this prediction comparatively in African birds by examining the response of the immune system to the mitogenic lectin, phytoahemagglutinin (PHA response) in relation to cooperative breeding. Among 66 species, of which 18 breed cooperatively, PHA response was significantly higher in cooperatively breeding species. This association appeared not to be confounded by body size, clutch size, nest position, coloniality or similarity owing to common phylogenetic descent. These results suggest that cooperatively breeding birds may have been selected to invest more than pair-breeders in defences against parasites. If so, then additional costs of philopatry and helping behaviour might be imposed on breeders, helpers and offspring.  相似文献   

16.
Bamboo forests, due to their special characteristics and ecological functions, play an important role in sustainable forest management and rural development in China. Over the past two decades, China has successfully established millions of hectares of bamboo forest, which has restored fragile ecosystems, provided benefits to local communities, alleviated rural poverty and eased timber shortages. However, there is potential for further improvements to the bamboo forest estate. This paper analyses the current state of bamboo forest resources and management, and the roles of the bamboo forest industry in social development, economic growth and ecosystem protection in China. We examine the main issues related to governance systems, local economic development and traditional management practices. Finally, we suggest some directions for future development.  相似文献   

17.
A significant proportion of the fishing population comprises small-scale fishermen and many studies illustrate that these people are exploited by middlemen in the process of fish marketing combined with money lending. The negative dependency gives rise to poverty and triggers indiscriminate fish catch that threatens fishery resources depletion. This article explores the root causes of failures in resource-led development from the viewpoint of coastal resource conservation. The study presents a case study of Chilika lagoon, India and focuses on the interaction between small-scale fishermen and middlemen. The findings reveal that most of the small-scale fishermen have been exploited by specific middlemen and the underlying causes of the present fish marketing structure stem from (i) indebtedness and (ii) the unstable situation because of perpetual conflicts over fishery resources among the fishers across Chilika lagoon. Based on these observations, this article presents some recommendations on fishery resource conservation from the perspective of a fish marketing structure.
Rajib ShawEmail:
  相似文献   

18.
In Europe, Britain was relatively early in being aware of the necessity of conserving natural coastal sites, though not as early as The Netherlands. In the 1960s and 1970s, increasing economic and tourist pressures in Europe prompted measures geared to the protection of other coasts in Europe. The promptness of the British reaction was a result of a sensitive public opinion and of powerful private trusts (National Trust with Enterprise Neptune) rather than of a commitment by the Government. In France a specific organization, in part inspired by the British principle, was set up. However, the French system is based much more on a public authority, theConservatoire de l’Espace Littoral et des Rivages Lacustres and on legislation (Coastal Law of 1986). Although very different in the beginning, French and British conservation politics today show many similarities, along with the similarities in the concerns of both countries.  相似文献   

19.
20.
Forest policies that devolve forest-use rights to local people have undergone development over the past few years in Laos. As collaboration between local people and forestry officials is seen as indispensable to effective and sustainable local forest management, the objective of this study is to clarify the issues pertinent to the resolution of latent conflict between these two stakeholders. The issues are examined by presenting two case studies in terms of forest management as perceived by local people and forestry officials; the first in a rich forest area and the second in a degraded forest. Issues relating to land and borders and social capital are identified as the most important in the degraded forest area, while social capital is a very important issue in the rich forest area. Our studies show that the problems of land and border issues in the degraded forest area were caused by an inappropriate resettlement policy. This can be interpreted as the mismanagement of social capital, and for effective local forest management it is very important to overcome problems of this nature. The effective use of social capital has so far been overlooked, however, in the establishment of collaborative forest governance at the local level.  相似文献   

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