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1.
    
Landscape diversity reflects the integrated natural characteristics of rural areas, to some extent, while industrial structure shows the regional social economic characteristics. Therefore, correlation research on rural industrial structure and landscape diversity may couple the natural environment and social economy, which is of great importance to rural sustainable development. In this paper, we carried through this research from two aspects. First, we made a qualitative analysis of the hierarchical correlation beween rural industrial structure and landscape diversity, and the correlation during different historical periods was also summarized. Second, taking Yongsheng County, Yunnan Province, China as a case study, we applied the method of hierarchical clustering to make a quantitative analysis of the clustering correlation between rural industrial structure and landscape diversity. The results show that there are correlations between rural industrial structure and landscape diversity. That is, different industrial structures may result in similar landscape diversity in developed rural areas; while in developing rural areas industrial structure cannot exclusively determine landscape diversity, which is also influenced by natural factors, such as landform, physiognomy and climate.  相似文献   

2.
Industrial SO2 is the most important air pollutant in China. This paper outlines the technological impacts on industrial SO2 emissions in China in terms of: amount, intensity, structure of energy consumption and structure of energy-intensive industries. It shows that industrial SO2 emissions have linear growth alongside increases in energy consumption, particularly the rise in coal consumption. The contribution of technological factors to decreases in the intensity of energy consumption is 25%, while the structural factor is 75%. The power industry accounts for 52.6% of total industrial SO2. Optimisation of the structure of energy consumption can reduce SO2 emissions by 1.98 million tonnes per year. We propose the following technological strategies for industrial SO2 abatement: adjustment of the system and structure of thermal power generating units, acceleration of flue gas desulphurisation projects, transformation of industrial structures, development of eco-industries and a reduction in energy consumption per unit product. In addition, an effective way to abate industrial SO2 emissions is to promote governance strategies to stricly enforce SO2 emission standards, conduct emission trading, and formulate incentives for encouraging cleaner production and clean energy development.  相似文献   

3.
Time series data on population change, economic development, climate change, water volume and quality and oasis land-use change were collected to study the interactions between these factors in the arid Tarim River Basin, China. The study reveals that precipitation and stream flow in headwater streams increased, but stream flow in the main Tarim River had reduced significantly over the past three decades. This implies that human activity, rather than climate change, dominated the recent environmental changes in the river basin. As a result of population growth and cultivated land expansion in the upper and middle reaches of the river, severe problems of water shortage, water pollution, death of natural vegetation, soil salinization, desertification and sand-dust storms have occurred, particularly in downstream areas of the river basin. These problems have had serious negative effects on the health of local people and sustainable social economic development in the region. Some development strategies are proposed to deal with these problems.  相似文献   

4.
The mountains hold the key to global ecological and social stability by virtue of being centres of biological and cultural diversity and the storehouse for water and other resources. However, they are becoming unable to sustain the demands of the changing life style of the growing number of inhabitants as well as the population in the plains and, therefore, the resources are depleting rapidly. Inadequacy of research and development (R&D) projects undertaken in mountain ecosystems is, perhaps, a major factor that has not enabled us to evolve and introduce suitable interventions to replenish and restore the health of the degraded mountains. In this article, taking the Indian Himalayan region as a case study, an effort has been made to understand the adequacy and appropriateness of R&D projects in mountain ecosystems by analysing the research and development projects implemented in this region from 1985–86 to1998–99. The analysis revealed inadequacy in the number and budgets of R&D projects implemented in this mountain ecosystem as a whole as well as in specific subject areas; the number of R&D projects implemented during this period was only 5.28% of the total projects, with a fund allocation of 4.45% of the total R&D budget of India, which appears to be inadequate considering the geophysical and bio-social importance of the Himalaya. The finding suggests that national funding agencies of mountain nations need to increase the number of R&D projects in mountain regions as a priority, with the intention of developing scientific packages capable of restoring the degraded ecosystem of the mountains and ensuring their sustainable development.  相似文献   

5.
6.
With rapid urban development, municipal solid waste (MSW) has become a pressing issue. Estimation of carbon discharge through municipal solid waste provides a way to assess environmental load of solid waste from the viewpoint of the carbon cycle. With few studies on carbon research and provides insights into human impacts on the carbon cycle. Based on a comprehensive fieldwork investigation of a typical Chinese tourist city – Haikou City, Hainan Island – the characteristics of MSW carbon discharge and human activities that influenced it were analysed. The results indicated that, in 2001, the total carbon discharge from 261.9 Gg of MSW was 105.1 GgC per year, and 174.6 kgC per capita per annum. Carbon is discharged in the form of food scraps (24%), plastics (20%), wood (17%), fabrics (14%), paper (13%), and dust and stone (12%). If landfill received all the waste, 4.7% of MSW carbon would be transformed into methane, with a value of 4.9 GgC. Between 1991 and 1999, Haikou's per capita MSW carbon discharge increased by 59.9%, and total MSW carbon discharge increased by 124.9%. MSW carbon discharge in Haikou is significantly affected by the growth of residential expenditure and urbanisation. Local characteristics of tourism also influence Haikou's MSW carbon discharge, not only in terms of its yearly variation, but also its monthly variation. Integrating data on carbon discharge with carbon consumption will provide a systematic view of the carbon metabolism in urban ecosystems, and further insights into the generation of urban environmental pollution.  相似文献   

7.
    
The construction sector carries out a very important role in the development of society. It is a basic component of economic activity, having a great influence on employment generation and country growth. The sector generates appreciable environmental changes and effects throughout the planet, leading to gradual exhaustion of natural resources and contamination of basic elements, such as air, water and soil. Recently, there have been advances in favour of more environmentally friendly buildings. Basically, sustainable construction has centred on residential and office buildings. It could be said that there is a lack of sustainability in the construction of industrial buildings, as they present characteristics which differ from other building typologies. This article aims to assess and analyze industrial building environmental effects, and considers a set of green study criteria, such as: location, materials, energy and water consumption, construction and deconstruction characteristics, and waste management in industrial building. At the same time, the studies are hierarchically structured into different assessment elements, such as: criteria, subcriteria and, finally, indicators, comprising the assessment model.  相似文献   

8.
Incentive approaches are believed to be indispensable for effective conservation and successful management in protected areas. However, the actual effectiveness of these approaches is still debatable. We carried out a case study in Wolong Biosphere Reserve (WBR), the largest reserve for the giant panda (Ailuropoda melanoleuca), to evaluate the effectiveness of incentives. We obtained data from government documents and statistics, interviews and surveys on the employment status of public sector and industries. Results indicated that government-paid community-based conservation projects provided the most widespread and direct economic incentives. The conservation sector and several industries including hotels, hydropower and tourism have directly raised the employment level of local communities. The hotel industry, driven by the development of tourism, has been the most effective means of increasing local employment. However, the problem of immigrants attracted by the improved economic situation in WBR should be considered in the management plans. Suggestions for WBR management include development of quality ecotourism, vocational education for local young adults and new policies encouraging employment of local labour, both in the reserve and outside. Lessons learned from this research are constructive for the management of other protected areas.  相似文献   

9.
Humankind is now using natural resources more rapidly than natural systems can replace them and has been doing so for approximately two and a half decades. Moreover, both natural capital and the ecosystem services it provides are being diminished at an unprecedented rate. Finally, the human population is expected to increase by three billion by 2050. This situation is clearly unsustainable, but it can be made less so by redesigning societal wastes so that they benefit the biospheric life-support system. Nature initiates and maintains a system of energy and nutrient cycling and, if the system integrity is maintained, provides alternative and redundant means that help stabilize functional capacity. The system is composed of opportunistic individuals that compete with other individuals to acquire the resources essential to their survival. The interrelationships within this aggregation of individuals (i.e. system components) are based on energy flow. This self-organizing and self-maintaining system is increasingly stressed by human activities. Humans are a part of, not apart from, this system and are governed by the same laws of nature. In short, an ecologically-based economic system is essential to sustainable use of the planet. The planet's life-support system has been a superb model of sustainability, which humans should emulate and become a part of more than they now are. When the biospheric life-support system is stressed to the point of disequilibrium, the results are disastrous for societies, individuals and ecosystems. Evolutionary processes have produced replacement systems following the five great biological extinctions. However, the probability is high that the next replacement system will not be as suitable for humankind as the present system. Sustainable practices are intended to prevent biospheric disequilibrium and maintain the present environmental conditions so favorable to humankind, including posterity.  相似文献   

10.
Quantifying landscape pattern and its change is essential for monitoring and assessment of ecological consequences of urbanization. Using the GIS-based land-use data for 2002, we combined moving window analysis along an urban-rural gradient and around the urban centre with landscape metrics to quantify the spatial pattern of urbanization in Beijing. The results of moving window analysis along the urban-rural gradient indicated that, for class-level metrics, the spatial pattern of urbanization could be quantified using landscape metrics, different land-use types exhibited distinctive spatial signatures, and, for landscape-level metrics, the increase in urbanization in the metropolitan Beijing region has resulted in dramatic increases in patch density (PD), edge density (ED), and patch and landscape shape complexity, and sharp decreases in the largest and mean patch size (MPS), agriculture land-use type, and landscape connectivity. The results of moving window analysis around the urban centre showed that the direction of urbanization could be quantified using the class-level metrics, and landscape-level metrics indicated similar results to gradient analysis. In general, moving window analysis showed that the increasingly urbanized landscape became compositionally more diverse, geometrically more complex, and ecologically more fragmented.  相似文献   

11.
The 1992 Earth Summit highlighted the critical role of consumption in affluent nations as a source of global environmental deterioration. While most developed countries have begun over the past decade to grapple with the difficult challenges of reducing household demand for energy and materials, sustainable consumption has yet to attract substantive attention in the United States. There exist, however, several strategic openings that American proponents of more environmentally benign household provisioning could exploit to launch a public dialogue about the environmental implications of contemporary consumption. First, public health professionals have in recent years begun to make significant strides publicizing the nutritional inadequacy of the American diet and the contributory role it plays in elevating incidences of chronic disease. Second, the rapid increase in the rate of obesity in the country is now coming to be understood as a health problem that is attributable to the prevalence of sedentary lifestyles. Finally, there is growing public concern in the United States over the accumulation of unprecedented levels of consumer debt and the epidemic of personal bankruptcies. The intent of this paper is to highlight the need to consider the personal dimensions of everyday life when formulating strategies to foster more sustainable consumption.  相似文献   

12.
Hierarchical control formulations are given for a simple predator-prey model: self-optimization of one subsystem, natural multi-goal optimization, man's multiparameter control of an ecosystem and man's control of a self-optimizing ecosystem. Natural multigoal optimization suggests how several levels of an ecosystem can be optimized simultaneously. The idea of management of a self-optimizing ecosystem takes into account the reactions of the ecosystem to man's activity.  相似文献   

13.
Scenarios of major terrestrial ecosystems in China   总被引:2,自引:0,他引:2  
The spatial pattern and mean-center shift of major terrestrial ecosystems, termed Holdridge Life Zones (HLZ), during the periods from 1961 to 1990 (T1), from 2010 to 2039 (T2), from 2040 to 2069 (T3) and from 2070 to 2099 (T4) were analyzed by combining the zonal patterns of climatic change in China and the climatic change scenarios of HadCM2 and HadCM3. The results showed that nival area would decrease rapidly with temperature increase in the future. HadCM2 and HadCM3 predicted that the nival areas might disappear in 552 years and 204 years, respectively. Using both HadCM2 and HadCM3, the five HLZ types with the largest areal extent are nival zone, cool temperate moist forest, warm temperate moist forest, subtropical moist forest and boreal wet forest, which collectively account for more than 50% of China's land mass. Among these five HLZ types, nival zone, warm temperate moist forest and boreal wet forest would decrease continuously, whereas subtropical moist forest and cool temperate forest would increase continuously during the four periods. HLZ diversity and patch connectivity would increase continuously in the 21st century. The shift distances of mean centers of HLZ types simulated using HadCM3 were markedly greater than those simulated using HadCM2, in general. The results from both HadCM2 and HadCM3 showed that boreal wet forest, subtropical moist forest, tropical dry forest, warm temperate moist forest and subtropical wet forest had bigger shift ranges, indicating that these HLZ types are more sensitive to the climatic change scenarios of HadCM2 and HadCM3.  相似文献   

14.
Cycling index is an important ecological indicator used in ecosystem analysis. The higher the cycling in an ecosystem, the higher the utilization of mass and energy within the system before it is lost due to respiration and other factors. For a stock-flow type ecosystem model at steady state, Finn’s cycling index (FCI) can be computed using simple matrix algebra. However, it is difficult to measure how well this index represents the actual cycling occurring in the system. In this paper, we study cycling in ecological networks using an individual based approach (particle tracking algorithm). This new simulation method provides access to the pathway data of individual particles that flow in the system, therefore one can quantify cycling using this pathway data quite literally. We used particle tracking simulations (PTS) to compute a cycling index using Finn’s idea of flux based cycling. Our simulation based results (using no matrix algebra) agree with Finn’s cycling index, verifying the accuracy of both the PTS, and the original linear algebraic formulation of FCI.  相似文献   

15.
16.
Although the existence of robust inverted biomass pyramids (IBPs) seems paradoxical, they are well known to exist in planktonic communities, and have recently been discovered in pristine coral reefs and in a reef off the North Carolina coast. Understanding the underlying mechanisms which produce inverted biomass pyramids provides new ecological insights. Some ecologists hypothesize that “the high growth rate of prey and low death rate of predators” causes IBPs. However, we show this is not always the case (see Sections 3.1 and 4). We devise predator–prey models to describe three mechanisms that can lead to IBPs: (1) well-mixed populations with large prey turn-over rate, (2) well-mixed populations with prey immigration, and (3) non-mixed populations where the prey can hide in refuges. The three models are motivated by the three ecosystems where IBPs have been observed. We also devise three refuge mediated models, with explicit refuge size, which incorporate different prey responses in the refuge, and we discuss how these lead to IBPs.  相似文献   

17.
《Ecological modelling》2007,208(1):56-67
Empirically observable energy and matter transfers in ecosystems create network structures commonly called food webs. The relation or interaction type associated with each link between pair-wise objects can be classified as (+, −) or (−, +) depending on the net gain or loss experienced by each object. If objects are not adjacent in the food web, then their observed direct interaction is neutralism (0, 0). From this perspective, a zero-sum balance exists between the number of positive and negative relations in the ecosystem. However, community-level relations arise from observable direct and unobservable indirect pathways within a food web, giving rise to indirectly mediated relations, mutualism (+, +) and competition (−, −). Determination of community-level relations requires a systemic or holistic approach. Utility measures from environ analysis in the broader frame of ecological network analysis (ENA) provide such a methodology to investigate the relations resulting from all observed and indirect transfers. This research demonstrates the methodology and shows three important results from the analysis. First, all objects in ecological networks are related either through their input and output environs, and therefore all objects interact with and influence the others in the web: there are no null community-level relations. Second, the community-level relations can and do differ from direct relations: what you see is not always what you get. Third, due to the web of trophic and non-trophic interactions, community-level relations usually have a greater occurrence of mutualism than competition making them more positive than the direct relations that produced them: this is the property called network mutualism.  相似文献   

18.
Based on cybernetic categories of natural control mechanisms, four generations of ecosystem models are distinguished: feed-forward, feedback, self-adaptation and self-organization models. The analysis of the natural control mechanisms in aquatic ecosystems suggests that different processes are controlled in different ways, and, although the four mechanisms were identified in historical sequence, they all operate simultaneously. The concept of self-organization of an ecosystem is introduced and specified for a model of an aquatic pelagic ecosystem. The concept of the ecosystem as a multilayer, multigoal and multiechelon hierarchical system with hierarchy of the levels of biological organization is also introduced.  相似文献   

19.
Based on cybernetic categories of natural control mechanisms, four generations of ecosystem models are distinguished: feed-forward, feedback, self-adaptation and self-organization models. The analysis of the natural control mechanisms in aquatic ecosystems suggests that different processes are controlled in different ways, and, although the four mechanisms were identified in historical sequence, they all operate simultaneously. The concept of self-organization of an ecosystem is introduced and specified for a model of an aquatic pelagic ecosystem. The concept of the ecosystem as a multilayer, multigoal and multiechelon hierarchical system with hierarchy of the levels of biological organization is also introduced.  相似文献   

20.
The development of approaches to estimate the vulnerability of biological communities and ecosystems to extirpations and reductions of species is a central challenge of conservation biology. One key aim of this challenge is to develop quantitative approaches to estimate and rank interaction strengths and keystoneness of species and functional groups, i.e. to quantify the relative importance of species. Network analysis can be a powerful tool for this because certain structural aspects of ecological networks are good indicators of the mechanisms that maintain co-evolved, biotic interactions. A static view of ecological networks would lead us to focus research on highly-central species in food webs (topological key players in ecosystems). There are a variety of centrality indices, developed for several types of ecological networks (e.g. for weighted and un-weighted webs). However, truly understanding extinction and its community-wide effects requires the use of dynamic models. Deterministic dynamic models are feasible when population sizes are sufficiently large to minimize noise in the overall system. In models with small population sizes, stochasticity can be modelled explicitly. We present a stochastic simulation-based ecosystem model for identification of “dynamic key species” in situations where stochastic models are appropriate. To demonstrate this approach, we simulated ecosystem dynamics and performed sensitivity analysis using data from the Prince William Sound, Alaska ecosystem model. We then compare these results to those of purely topological analyses and deterministic dynamic (Ecosim) studies. We present the relationships between various topological and dynamic indices and discuss their biological relevance. The trophic group with the largest effect on others is nearshore demersals, the species mostly sensitive to others is halibut, and the group of both considerable effect on and sensitivity to others is juvenile herring. The most important trophic groups in our dynamical simulations appear to have intermediate trophic levels.  相似文献   

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