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1.
Traditional crop landraces play dynamic roles in the expression of native biological and cultural diversity via their central position in the genetic resource base, agroecosystems and social heritage of indigenous peoples. Farmer varieties provide farmers with an “agricultural survival kit” for household welfare and for adaptation to changing conditions. These varieties meet local cultural practices and environmental constraints, and play an intrinsic role in cultural survival by constituting a living repository of ancestral customs including cultivar-specific recipes, songs, handicrafts, stories of origin, and unique planting, harvesting, processing, and storage rituals and techniques. The centrality of rice in Southeast Asian agricultural and social systems, contrasted with the significant erosion of rice-based biological and cultural diversity in native communities, calls for increased attention to the links between traditional rice varieties and indigenous rice-based customs. This study represents the research efforts of rice farmers pertaining to the Tado clan, a Kempo Manggarai community on Flores␣Island, in association with USA academicians. Research results demonstrate: (i) a complex suite of upland rice-based ethnobotanical traditions; (ii) significant and␣dynamic regional flux and dissemination of “old” and “new” landraces; (iii)␣community-level maintenance of distinct genotypes across a range of microenvironments; (iv) localized “extinctions” of ancestral landraces within 1–2 generations and a concomitant loss of related traditions; and (v) the contributions of a collaborative (indigenous and academic) approach to ethnographic and agronomic research.  相似文献   

2.
Objectives and methods of mapping the ecological state of the plant cover at different spatial levels—federal, regional, and local—are analyzed. The maps used as examples are as follows: at the federal level, “Ecological State of Rangelands in Russia” (1:10 000 000); at the regional level, “Vegetation of Moscow Oblast” (1:200 000); and at the local level, “Vegetation of Narofominskii Raion” and “Current State of the Plant Cover in Narofominskii Raion” (1:50 000).  相似文献   

3.
The southern Yucatán has been identified as a deforestation hot spot. Land-change studies document the extent of forest loss at a regional scale, and case studies provide insights into the drivers of deforestation at the household level. Those studies have paid minimal attention to sub-regional analysis, especially to discrete land-management units above the household level. This analysis of upland forest change addresses the range of variation in deforestation among 96 ejidos (communal lands) and the Calakmul Biosphere Reserve, the two dominant land-tenure and land-management units in the region. Satellite imagery, census, and land-tenure data are used to establish the extent and location of deforestation patterns, and multivariate techniques are employed to identify biophysical and socioeconomic variables that explain such patterns. Results show that, for the 1984–1993 period, deforestation in the southern Yucatán was not as prevalent as implied by its hot spot designation. Three clusters of deforestation are identified. A logistic regression analysis establishes that size of forest holdings, population growth, and location in the precipitation gradient correlate with ejidos that experienced higher deforestation rates than the rest of the land-tenure units. For the 1993–2000 period, conservation programs and changes in the economic context of this “hollow frontier” contributed to reduce deforestation rates and extent. This analysis illustrates the spatio-temporal heterogeneity of much tropical forest change and caution that it should bring to simple formulations of modeling this change and prescribing policies to control it.  相似文献   

4.
The paper addresses the topic of wealth accumulation in Russia. This phenomenon plays an important role for the understanding and forecasting the future economic and social development of the country. The “westernized” paradigm calls for hard honest work during the life and approves getting a reward in a form of wealth in the end. When brought to Russia, this paradigm faces the orthodox traditions and rules together with the post-soviet mental patterns. In this paper, we consider how the pattern “first accumulate wealth, then consume it” competes with its opposition, the pattern “first consume wealth, then accumulate it” in Russia. We base our discussion on the consumers’ simple optimization problem, which exhibits a bifurcation between those two patterns depending on the relation between the consumption “impatience” and the wealth growth rate. We also suggest a framework to model the phenomenon of unfair wealth through impulse type of wealth development.  相似文献   

5.
The developing countries i.e., the non-Annex-I countries (parties to the Kyoto Protocol but not responsible to any reduction target yet) in the Kyoto Protocol whose economies are in transition are also allowed to reduce GHG emissions. Among these, the countries that have accepted the Kyoto Protocol may be benefited from CDM projects to promote sustainable development. The developed countries i.e., the Annex-I countries (that have signed the Kyoto Protocol & are responsible to have specific GHG emission reduction target) or the investing countries, in return, have privilege to purchase CER credits (in units equivalent to one tonne of CO2 gas emission reduction) to meet the emission target as specified in the Kyoto Protocol. The key step in understanding about CDM is to grasp the concept of “baseline” and “additionality”. The “Baseline” is the emissions level that would have existed if a CDM project had not happened. The feature of an approved CDM project is that the planned reductions would not occur without the additional incentive provided by emission reduction credits; this concept is known as “Additionality”. According to environmental additionality concept, baseline emission minus project emission is equal to emissions reduction. “Investment Additionality,” ultimately rejected during negotiation of the “Marrakech Accords” and “Financial Additionality,” are the two important concepts. The concept of trading of CER matches to the idea of Pigovian tax (equal to the negative externality and which is considered one of the “traditional” means of bringing a modicum of market forces) in Economics, making pollution more costly to the polluter, as the polluters have negative cost since they save money by polluting; hence, there are supposed negative externalities associated with the market activity. Economic theory predicts that in an economy where the cost of reaching mutual agreement between parties is high and where pollution is diffuse, Pigovian tax will be an efficient way to promote the public interest and will lead to an improvement of the quality of life measured by the Genuine Progress Indicator and other human economic indicators, as well as higher gross domestic product growth. We can seek a level of pollution such that the marginal savings (MS) to one polluting unit from pollution (−MC) is equal to marginal damage (MD) from pollution over the entire population, since pollution is a public bad i.e., MS (x*) = ∑MDi (x*) where ∑Di (x) is the total damage. Though the responsibility of reduction in emission does not lie on the non-Annex-I countries, still effort of maintaining global emission balance can be expected equally from developed and developing countries. The responsibilities of Kyoto Protocol are (a) to reduce global GHG emissions, (b) to bring about sustainable development in the developing countries lie on above two groups since its effect on February 16, 2005. Different polluters have different costs of pollution control. The least costly way of controlling pollution from various sources that reflects different costs of pollution control making the set of environmental regulations to achieve the emission target at the lowest cost makes the regulation cost-effective. Though efficiency is not attainable for many regulations, cost-effectiveness is attainable.  相似文献   

6.
Studies investigating the local ecological knowledge (LEK) held by fishermen about the fishing resources have indicated that fishermen’s LEK may have the potential to improve fishery management, by providing new information about the ecology, behavior and abundance trends of fish and other aquatic animals. Our major aim is to undertake a brief review of published ethnoichthyological studies with a focus on coastal Brazilian fisheries and freshwater fisheries in both Brazil and Southeast Asia. Based on such review, we provide 29 hypotheses on fish ecology based on fishermen’s LEK and compare them with what is already known from the biological literature, using an arbitrary ‘likelihood’ measure: “Low likelihood” corresponded to unexpected hypotheses, which contradict existing biological data. “Medium likelihood” corresponded to hypotheses that could not be compared to available scientific knowledge. Hypotheses that agree with scientific data were considered as “High likelihood”. We therefore discuss these three categories of hypotheses about several distinct topics, such as migration, reproduction, feeding habits, abundance patterns, ecological relationships between fish and their predators, and fishing pressure. Our results may contribute to the fisheries management and research in the studied regions and other similar places, besides raising the interest of biologists to properly include fishermen’s LEK when planning and conducting fisheries surveys. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

7.
Modeling changes in paddy rice sown areas in Asia   总被引:1,自引:0,他引:1  
Paddy rice fields in Asia account for over 90% of global total rice cultivation area, and the major rice-producing countries of Asia account for over one-half of the world’s population. Monitoring and understanding the dynamic changes in paddy rice agriculture in Asia are very important for agricultural sustainability, food and water security, and greenhouse gas emissions. This paper presents a crop choice decision model that dynamically simulates future changes in sown areas of paddy rice in Asia. This model was developed under the framework of Action-in-Context (AiC) with the aim of understanding land users’ decisions on crop choices among a set of available alternatives using a crop utility function. Empirical validation for the model conducted after model construction indicated the reliability of the model for addressing the complexity of current agricultural land-use change and its capacity for investigating long-term scenarios in the future. Finally, the model was applied for future scenario analysis over a time frame of 30 years with 5-year increments, beginning from the year 2005. The simulation results provided insights into rates and trajectories of changes in Asian rice areas over the test period, with the resulting implications for future agricultural sustainability in Asia. These outcomes can improve understanding of projected land-use changes and explain their causes, locations and consequences, as well as providing support for land-use planning and policy making.  相似文献   

8.
The risk of erroneous regulation in multilevel normative environmental chains, at the federal, regional, and lower levels, down to the corporate one, has been studied. This risk has been demonstrated to increase unacceptably rapidly in the framework of the existing system of “unconditional acceptance” of normative standards. To mend the situation, it is necessary to use the “conditional acceptance” model by regarding post hoc decisions made at higher levels as a priori ones at the next (lower) levels. A strategy of environmentally and economically balanced corporate regulation of nature management through minimization of the losses resulting from both excessive caution and breaching the existing regulations has been proposed. This system, combined with the European approach to nature conservation, requires that the “riskless” regulation should be abandoned and is expected to improve the parameters of nature management quality by three to four orders of magnitude.  相似文献   

9.
Defining climate-change victims   总被引:1,自引:0,他引:1  
This article introduces the concept of “climate-change victims” and classifies categories of threats and groups of people who would be vulnerable to and victimized by human-induced climate change. (The full, correct wording is “human-induced climate-change victims”, but we will use just “climate-change victims” in the rest of the article.) It offers a definition with three levels of climate-change victimization and differentiates “climate-change victims” from “natural-disasters victims” and from “climate-change migrants”. The article sets an agenda for a new type of victimhood and could lead to further research on possible prevention, accountability measures, environmental tribunals, and compensation mechanisms to recompense climate-change victims.  相似文献   

10.
According to the basic concept of the theory dealt with in this study, autocenosis, i.e., a self-regulatory host-symbiont system, rather than an individual, is the individual-level unit. Then, democenosis, which is a system of autocenoses, corresponds to the population level. Therefore, natural selection of autocenoses rather than individuals occurs in a democenosis, and auto- and democenoses, rather than “individuals” and “populations,” are components of food chains and webs. However, the symbiotic approach does not exclude the population paradigm and will be developed in parallel with it.  相似文献   

11.
Woody biomass generated in short-rotation coppice (SRC) plantations with aspen (Populus tremula L.) has good properties for bioenergy crop production: annual yields are high, labour input per year is low, and it is ecologically valuable because of the multi-year rotation periods. Eastern Germany has a special advantage in producing bioenergy crops: the former “agricultural cooperatives” built up quite large farms with, compared to Western Germany, comparatively large fields. Therefore, a modelling study of the potential and the impacts of aspen SRC plantations in the five eastern federal states of Germany under the recent climate and future climate projections was conducted. The ecophysiological forest growth model 4C was used to simulate the growth of aspen SRC plantations and their impacts on carbon in soils, and groundwater recharge, on selected suitable areas currently under crops but with marginal site conditions for cropping. A clear signal to enhanced growth condition over the whole area can be seen in the simulation of the mean annual woody biomass yield under conditions of climate change, which increased from 7.47 t DW ha−1 a−1 under the recent climate to 9.26 t DW ha−1 a−1 at the end of the considered future period 2034–2055 under climate change. The mean soil carbon sequestration rate was 0.81 t C ha−1 a−1 under the recent climate and could rise up to 0.93 t C ha−1 a−1 under the assumption of climate change. On the other hand, the mean annual percolation rate, used as an indicator of impacts on the regional water budget, will diminish under future climatic conditions. The results suggest that aspen SRC plantations are a suitable contribution to regional CO2 mitigation and carbon sequestration under possible change of climate, but that negative impacts on the regional water budget are possible.  相似文献   

12.
A critical review of the multidisciplinary literature on sustainable development reveals a lack of a comprehensive theoretical framework for understanding sustainable development and its complexities. A critical review shows that the definitions of sustainable development are vague; there is a lack of operative definitions and disagreement over what should be sustained; the concept is unclear in terms of emotional commitment; and it “remains a confused topic”, “fraught with contradictions”. This article aims to theoretically synthesize the interdisciplinary literature on sustainable development, and then identify the results by broad categories. Therefore, this article uses conceptual analysis, which reviews multidisciplinary literature on sustainable development, which recognizes patterns and similarities within the literature, then it synthesizes the patterns to different categories and independent concepts, where each concept has distinctive meanings and represents close ideas on sustainability. The analytical process elaborates seven concepts that together assemble the theoretical framework of ‘sustainable development’ and each concept represents distinctive meanings of the theoretical framework.  相似文献   

13.
太湖流域经济与城市化过程持续加速而耕地流失及粮食供需形势日趋严峻。基于最小人均耕地面积(Smin)和耕地压力指数(K)模型及其分析与预测,定量研究流域耕地变化和粮食生产特征及趋势。结果表明:1985年以来,流域人口不断增长,耕地面积随人均GDP增长呈显著的对数型减少,粮食总产波动降低;Smin和K值经过1985~1997年的平缓波动后持续上升,2003年之后又有所降低。区域分析结果揭示了整个流域耕地压力凸显的现实;未来10 a耕地生产力提高促使Smin逐年减小,但Sa递减速度较快,K值上升明显;两种预测情景表明降低粮食自给率一定程度上缓解了区域耕地压力,但口粮供给还有缺口,由此提出转变经济发展方式、创新耕地利用和粮食生产的调控机制等相关建议  相似文献   

14.
Excessive nitrogen (N) fertilization in intensive agricultural areas in the Taihu Lake region of East China has resulted in low N utilization efficiency and serious environmental problems, giving rise to the need for an urgent reduction in the N fertilization rate. However, no holistic evaluations of rice (Oryza sativa L.) yield effect and environmental effects of N fertilization have been conducted when recommending an optimal N rate. The current study provides an economic indicator and an evaluation model to account for the environmental effects of different N losses after N fertilizer application in the ecological and economic N rate for one rice season in the Taihu Lake region. Based on the assembled data and economic index, a general economic evaluation model to measure efficiently the cascading costs of the chemical N cycle at the regional scale was developed. Thereafter, fertilizer-stimulated benefit curves and fertilizer-induced cost curves were generated to determine an economically and ecologically optimal N application rate. The results revealed that the maximum net benefits were 3,123 yuan ha−1 at 202 kg N ha−1 for one rice season in the Taihu Lake region. Additional N application up to a rate of 263 kg N ha−1 would increase rice production, but the increase in the total marginal costs would be slightly greater than the increase in marginal benefits. Among the marginal costs, the fertilizer and acidification costs were the greatest expenses, amounting to 1,716 yuan at 263 kg N ha−1, followed by eutrophication and global warming costs. When compared with the conventional N fertilization rate, this recommended rate could decrease the amount of N applied to rice from 10 to 40%, thereby, enabling optimum economic and ecological results.  相似文献   

15.
Between the tenth and twentieth century the population of Paris city increased from a few thousand to near 10 million inhabitants. In response to the growing urban demand during this period, the agrarian systems of the surrounding rural areas tremendously increased their potential for commercial export of agricultural products, made possible by a surplus of agricultural production over local consumption by humans and livestock in these areas. Expressed in terms of nitrogen, the potential for export increased from about 60 kg N/km2/year of rural territory in the Middle Ages, to more than 5,000 kg N/km2/year from modern agriculture. As a result of the balance between urban population growth and rural productivity, the rural area required to supply Paris (i.e. its food-print) did not change substantially for several centuries, remaining at the size of the Seine watershed surrounding the city (around 60,000 km2). The theoretical estimate of the size of the supplying hinterland at the end of the eighteenth century is confirmed by the figures deduced from the analysis of the historical city toll data (octroi). During the second half of the twentieth century, the ‘food-print’ of Paris reduced in size, owing to an unprecedented increase in the potential for commercial export associated with modern agricultural systems based on chemical N fertilization. We argue that analysing the capacity of territories to satisfy the demand for nitrogen-containing food products of local or distant urban population and markets might provide new and useful insights when assessing world food resource allocation in the context of increasing population and urbanization.  相似文献   

16.
Management of the old industrial regions’ development is a very actual problem, in particular for the post-Soviet countries. It is connected with the fact that the purposes of manufacture modernization which provide employment and incomes of the population of such regions, can contradict requirements of environmental protection. Here the most different scenarios of development are possible which need to be evaluated. Usual neoclassical criteria for this purpose do not match. Therefore, in our paper, there was a task to develop such criterion which can be used for regulation of the old industrial regions’ development taking into account the environmental factor. The paper begins with construction of regional economy model. Our model based on the J. Forrester's “world model” idea, i.e. it considers the influence of environmental pollution (atmosphere, water, earth) on the population disease level, and then—on the lifetime and the human capital; the latter ones are considered as one of the most important factors of the economic growth. On the ground of this model, the consequences for realization of different scenarios of the regional economy development are estimated. To substantiate the regulation of regional economy, the criterion of sustainable development, based on the idea of simultaneous improvement of economic and ecological parameters, is offered. The main feature of the criterion offered is that, first of all, it guarantees simultaneous improvement of each of the chosen indicators of the region’s development, and, second, allows considering interests of various coalition groups by finding realistic compromises at a choice of ways of old industrial regions’ development.  相似文献   

17.
Human society consumes resources that it is not able to reproduce. Human activities are still based on “open cycles,” starting from a condition of natural environmental balance and reaching an environmental imbalance. The challenging scope of scientific and technological research towards sustainability appears clear if it is based on this analysis: to find development systems based on “closed cycles” of resources. The challenging objective of realizing closed cycles leads to a definition of sustainability that indicates the path to sustainable development, as well as stating the general principle. It also provides a key to the qualitative measurement of sustainability. This means that the sustainability level of a system can be measured by measuring its capacity to avoid the consumption of resources. Zero consumption is a necessary condition for sustainability, and brings about as a side effect the highly desired “zero-waste” result. Materials entering the proposed endless scheme pass through the process of usefulness without losing their capacity to feed the system again after being used. Thus, the concept of “consumption” itself is replaced by one of “use” when resources are inserted into closed loops capable of feeding human development. The application of the closed cycle sustainability criterion particularly displays its feasibility, and a theoretical guiding role, in the energy sector. Energy vectors such as hydrogen and electricity enable the closure of the energy resources loop by effectively approaching the objective of “zero consumption” (and the side result of “zero waste”) through already demonstrated technological solutions.  相似文献   

18.
This study has indicated that there is close relationship between development density and environmental quality; therefore, it is necessary to decide the form of development carefully beforehand. The form of development is shaped either by new development or urban renewal which is a major tactic nowadays adopted by the Hong Kong Government to improve the living condition of the citizens and the quality of the built environment. This study is limited to urban renewal and aims to find out the major urban design considerations for sustaining the environment. Through a questionnaire survey carried out in Hong Kong, the opinions of architects, planners, property development managers, and local citizens were sought and evaluated, and critical design factors for enhancing environmental sustainability of urban renewal projects are highlighted. The results derived from factor analysis indicated that certain design considerations should be incorporated for sustaining the urban environment. “Land Use Planning”, “Quality of Life”, “Conservation & Preservation”, “Integrated Design”, “Provision of Welfare Facilities”, and “Conservation of Existing Properties” were believed to be the significant underlying factors for achieving environmental sustainability of local urban renewal projects. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

19.
The continuous growth of world population and the intensification of urbanization process create a challenge to environment quality and sustainable development around the world. In this paper I tried to conduct a forecast analysis of near-future urbanization related population growth worldwide, based on recent demographic trends. Such an analysis can provide important insights into the prospects for changes in the size and composition of world population and in urbanization process. Optimal polynomial functions were used to fit historical trajectories of population dynamics, and the detailed forecasts of the population mainly over the period 2010–2030 were conducted and analyzed. If the past pattern continues, world total population would increase to 7.94–8.33 billion in 2030 and the annual growth is expected to continually decline in the forecast period. Global total population would stop increasing during the period 2050–2060 and would not exceed 9.5 billion in the future. The total population of Africa, Asia, Oceania, South America, North & Central America would separately increase to 1.35–1.41, 4.86–5.65, 0.04–0.05, 0.44–0.45, and 0.71–0.72 billion in 2030. Europe’s total population is forecast to decline to 0.64–0.67 billion in 2030. World’s rural population is expected to grow to the maximum during the period 2015–2020 and would greatly decline after that period. Global rural population would reach 3.12–3.41 billion in 2030. Rural population in Asia and Africa is estimated to increase and achieve the maximum around 2025 and decline thereafter. For other regions, the rural population would continually decline in the forecast period. Urban population in the world would continually grow and reach 4.72–5.00 billion in 2030, an increase of 48.6–57.8%. However the annual growth of urban population is expected to increase to the maximum (6.86 million/year) during the period 2020–2025 and then decline in the following years. Urban population is projected to continually grow in all regions excepting Europe. Europe’s urban population is expected to decline in the period 2010–2030. Urbanization process worldwide, represented by the ratio urban population versus total population (RUT) and the ratio rural population versus urban population, is expected to continue during the period 2010–2030. The RUT of the world is projected to reach 0.5 before 2010 and would continue to increase in the forecast period. Global RUT is estimated to reach 0.56 in 2030. However, the regional patterns of urbanization process would be diverse. Europe’s RUT is estimated to continually decline in the forecast period and reach 0.68 in 2030. The RUT for Africa and Caribbean would continually increase before 2030, while the RUTs for Asia and South America are estimated to achieve their maximums around 2025 and decline in the following years. Oceania and North & Central America would thoroughly realize urbanization (≈1) during the periods 2020–2025 and 2025–2030. The expansion of world population and urbanization will continually exert a stronger stress to environment quality and sustainable development in a near future. However we may expect this situation would start to change from mid-21st century after total population has achieved its maximum. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

20.
Council Regulations (EC) No 1257/1999 and the EU Soil Thematic Strategy give great importance to soil and land conservation to develop knowledge driven governance for rural development. In the hilly areas of Italy cultivated intensively, and especially in the ones devoted to viticulture, agricultural practices determine high loss of soil with consequent degradation of the soil resource. In addition to it, offsite effects of soil erosion can be unsustainable, due to sediment transfer to the channel network and infrastructures. In order to achieve a sustainable rural development there is a need for tools and instruments to allow European regional administrations, to develop, implement, manage and monitor rural development plans. To counteract the environmental threats intensified by agricultural activity, the environmental functions “soil erosion control” and “water runoff control” were investigated in the Chianti area by using GIS. To determine the EMR (Environmental Minimum Requirements) values for soil erosion the “regeneration” capability of soils was considered, and the value of estimated soil loss was compared with the value of soil reformation. A scenario analysis was also performed to evaluate the effectiveness of the agroenvironmental measure “grass cover” in reducing erosion. The concept of tolerable erosion based on soil productivity and soil reformation rate only is reductive and off-site effects of soil erosion should be also taken into account. For this reason, it was proposed to extend the concept of hydrogeological risk to soil erosion by implementing the notion of soil erosion tolerance (T) with the new concept of environmental risk of soil erosion (ERSE). The new ERSE index takes into account all the in- and off-farm externalities of soil erosion. For this reason, it can be considered an aggregated environmental indicator that enables policy makers to evaluate the impacts of soil erosion by following an holistic approach.  相似文献   

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