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Although good general principles for climate change adaptation in conservation have been developed, it is proving a challenge to translate them into more detailed recommendations for action. To improve our understanding of what adaptation might involve in practice, we investigated how the managers of conservation areas in eastern England are considering climate change. We used a written questionnaire and semi-structured interviews to collect information from managers of a range of different conservation areas. Topics investigated include the impacts of climate change perceived to be of the greatest importance; adaptation goals being set; management actions being carried out to achieve these goals; sources of information used; and perceived barriers to taking action. We identified major themes and issues that were apparent across the sites studied. Specifically, we found ways in which adaptation had been informed by past experience; different strategies relating to whether to accept or resist change; approaches for coping with more variable conditions; ways of taking a large-scale approach and managing sites as networks; some practical examples of aspects of adaptive management; and examples of the role that other sectors can play in both constraining and increasing a conservation area’s capacity to adapt. We discuss the relevance of these findings to the growing discussion in conservation about identifying adaptation pathways for different conservation areas and a potential progression from a focus on resilience and incremental change to embracing “transformation.” Though adaptation will be place-specific, we believe these findings provide useful lessons for future action in both England and other countries. 相似文献
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Berien Elbersen 《Journal of Environmental Planning and Management》2005,48(1):37-63
In this paper the function of protected nature in rural living environments is discussed in relation to residential choice, appreciation of the residential environment and rural development policy. In five case studies a comparison is made between the situation of protected natural areas in the Netherlands, England and Spain. The research results show that protected natural areas are an increasingly popular endogenous quality of rural regions as they have the ability to influence the residential choice and satisfaction of households. Therefore, they have not only become an important driving factor in the attraction of residential and other consumption-orientated activities towards rural areas but also need to be considered in policy formulation. After all, choices have to be made when different functions need to be combined in rural areas. Different activities may have both positive and negative effects on each other and regulatory measures are needed to tune their co-existence. For a sustainable and balanced development of rural areas it is therefore very important to create basic conditions that will make the combination of activities possible within the specific national and regional contexts. 相似文献
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Effects of forest clearcutting in New England on stream macroinvertebrates and periphyton 总被引:3,自引:0,他引:3
Clearcutting may alter stream biota by changing light, temperature, nutrients, sediment particle size, or food in the stream. We sampled macroinvertebrates during late summer of 1979 in first and second order headwater streams draining both two- and three-year-old clearcuts and nearby uncut reference areas in northern New England, USA. Periphyton were sampled throughout the summer by placing microscope slides in these streams for 13–37 days. Periphyton cell densities on these slides following incubation were about six times higher in cutover than in reference streams. Green algae (Chlorophyceae) accounted for a higher proportion of total cell numbers in cutover than in reference streams, whereas diatoms (Bacillariophyceae) dominated the reference streams. The macroinvertebrate density in cutover streams was 2–4 times greater than that in the reference streams, but the number of taxa collected was similar in both cutover and reference streams. Higher numbers of mayflies (Ephemeroptera) and/or true flies (Diptera) in the cutover streams accounted for the differences. Because nutrient concentrations in the cutover streams were nearly the same as those in the reference streams, these differences in macroinvertebrate and periphyton densities were apparently caused by higher light levels and temperature in the streams in the clearcuts. Leaving buffer strips along streams will reduce changes in stream biology associated with clearcutting.Contribution from the Northeastern Forest Experiment Station, USDA Forest Service, Durham, New Hampshire 03824, USA. 相似文献
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鄂西南民族地区县域经济实力综合评价 总被引:1,自引:0,他引:1
《资源开发与市场》2016,(3)
从总量规模、人均水平、发展速度、发展潜力四个方面遴选18项指标,构建了县域经济实力评价指标体系。以湖北省平均水平为依据,确定了各项指标的基准值;借助专家咨询和层次分析方法确定了各项指标的权重,构建了县域经济实力评价模型。采用该模型对鄂西南民族地区10县(市)县域经济实力进行了评价,结果表明:恩施市、利川市、巴东县、五峰县的综合经济实力略高于全省平均水平,其他6县未达到全省平均水平。 相似文献
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Arnold L. O'brien 《Environmental management》1988,12(5):627-636
In New England, patterns of glacial deposition strongly influence wetland occurrence and function. Many wetlands are associated with permeable deposits and owe their existence to groundwater discharge. Whether developed on deposits of high or low permeability, wetlands are often associated with streams and appear to play an important role in controlling and modifying streamflow. Evidence is cited showing that some wetlands operate to lessen flood peaks, and may have the seasonal effect of increasing spring discharges and depressing low flows. Wetlands overlying permeable deposits may be associated with important aquifers where they can produce slight modifications in water quality and head distribution within the aquifer. Impacts to wetlands undoubtedly will affect these functions, but the precise nature of the effect is difficult to predict. This is especially true of incremental impacts to wetlands, which may, for example, produce a change in streamflow disproportionate to wetland area in the drainage basin, i.e., a nonlinear effect as defined by Preston and Bedford (1988). Additional research is needed before hydrologic function can be reliably correlated with physical properties of wetlands and landscapes.A model is proposed to structure future research and explore relationships between hydrologic function and physical properties of wetlands and landscapes. The model considers (1) the nature of the underlying deposits (geologic type), (2) location in the drainage basin (topographic position), (3) relationship to the principal zone of saturation (hydrologic position), and (4) hydrologic character of the organic deposit. 相似文献
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Biodiversity conservation has undergone a profound change in philosophy, policies and management approaches over the last
forty years. The traditional top–down approach to nature protection has been widely criticized for failing to include critical
social elements in management practices, and is being gradually replaced by a slew of participatory strategies under the rubric
of bottom-up conservation. The new approach recognizes local communities as key partners in wildlife management and seeks
their participation in social development and biodiversity conservation. However, every social context is different in its
structure and functions, and in the way social groups respond to calls for participation. In order to gain a better understanding
of the approach and the barriers encountered in its implementation, a questionnaire survey of 188 households was employed
in the communities of the Upper Mustang extension of Annapurna Conservation Area (ACA) in Nepal. The study provides a comparative
analysis of community participation and its barriers between Non-Tourist (NT) and Tourist (TV) villages. The results revealed
important differences between the two groups in terms of their participation in community programs, barriers to participation,
and perception of benefits from participation. Owing to their distinct spatial, demographic and attitudinal differences, the
two village groups have their own sets of needs, values and motivation factors which cannot be generalized and treated as
such. The research clearly identifies the need for the conservation agency to be creative in devising strategies and initiatives
appropriate to specific social groups so as to optimize their input in participatory conservation. 相似文献
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KRIENGKORN BEJRAPUTRA 《Natural resources forum》1983,7(2):167-174
Thailand used 42% of its export earnings to pay the 1981 oil import bill of US$3 billion. The present difficult economic situation is caused by the country's increasing dependence on imported oil which has risen from 50% of total energy consumption in 1962 to 75% in 1981. Contributing factors include basic problems in energy consumption patterns, inadequate pricing structures and a lack of a clearly-defined responsibility over the country's energy management. To remedy the present situation the Government is embarking on a large-scale programme based on the utilization of natural gas, hydroelectric power, lignite and imported coal, which should reduce the share of imported oil in Thailand's total energy consumption to 38% in 1990. En 1981, la Thailande a consacré 42 pour cent du revenu de ses exportations à régler sa facture pétrolière qui s'est chiffrée à 3 milliards de dollars des Etats-Unis. Les difficultés de la situation économique actuelle sont le résultat de la dépendance croissante du pays à l'égard du brut d'importation qui représentait, en 1981, 70 pour cent de la consommation totale d'énergie contre 50 pour cent en 1962. Parmi les causes de cette situation, il faut citer les problèmes qui sont à la base des changements de structures de la consommation d'énergie, de mauvaises politiques de prix et l'absence d'une stratégie clairement établie en ce qui concerne la gestion des ressources énergétiques du pays. Pour remédier à cette situation, le gouvernement s'est lancé dans un programme à grande échelle basé sur l'utilisation du gaz naturel, de la force hydroélectrique, du lignite et du charbon d'importation qui devraient pouvoir réquire à 38%, en 1990, la part d'importation du pétrole d'origine érangère de la Thailande Tailandia utilizó el 42 porciento de su ingreso por exportación para pagar tres mil millones de dólares correspondiente a la importación de petróleo durante 1981. La dificultad presente es causada por la creciente dependencia en petróleo importado que ha aumentado del 50 porciento del consumo total de energía en 1962 al 75 porciento en 1981. Los factores que contribuyen a esta situatión son: problemas básicos en la estructura del consumo y de precios y la falta de una clara delimitación de responsabilidades en la administractión del sector de energía. Para remediar esta situación el Gobierno se ha embarcado en un programa de gran escala basado en la utilización de gas natural, energía hidroeléctrica, lignito y carbon importado lo cual deberá reducir al 38 porciento del consumo de 1990 la parte del petróleo importado. 相似文献
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William H. Armstrong Mathias J. Collins Noah P. Snyder 《Journal of the American Water Resources Association》2012,48(2):306-320
Armstrong, William H., Mathias J. Collins, and Noah P. Snyder, 2012. Increased Frequency of Low‐Magnitude Floods in New England. Journal of the American Water Resources Association (JAWRA) 48(2): 306‐320. DOI: 10.1111/j.1752‐1688.2011.00613.x Abstract: Recent studies document increasing precipitation and streamflow in the northeastern United States throughout the 20th and early 21st Centuries. Annual peak discharges have increased over this period on many New England rivers with dominantly natural streamflow – especially for smaller, more frequent floods. To better investigate high‐frequency floods (<5‐year recurrence interval), we analyze the partial duration flood series for 23 New England rivers selected for minimal human impact. The study rivers have continuous records through 2006 and an average period of record of 71 years. Twenty‐two of the 23 rivers show increasing trends in peaks over threshold per water year (POT/WY) – a direct measure of flood frequency – using the Mann‐Kendall trend test. Ten of these trends had p < 0.1. Seventeen rivers show positive trends in flood magnitude, six of which had p < 0.1. We also investigate a potential hydroclimatic shift in the region around 1970. Twenty‐two of the 23 rivers show increased POT/WY in the post‐1970 period when comparing pre‐ and post‐1970 records using the Wilcoxon rank‐sum test. More than half of these increases have p < 0.1, indicating a shift in flow regime toward more frequent flooding. Region wide, we found a median increase of one flood per year for the post‐1970 period. Because frequent floods are important channel‐forming flows, these results have implications for channel and floodplain morphology, aquatic habitat, and restoration. 相似文献
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Wigand C McKinney RA Chintala MM Charpentier MA Groffman PM 《Journal of environmental quality》2004,33(3):1144-1151
Coastal salt marshes are a buffer between the uplands and adjacent coastal waters in New England (USA). With increasing N loads from developed watersheds, salt marshes could play an important role in the water quality maintenance of coastal waters. In this study we examined seasonal relationships between denitrification enzyme activity (DEA) in salt marshes of Narragansett Bay, Rhode Island, and watershed N loadings, land use, and terrestrial hydric soils. In a manipulative experiment, the effect of nutrient enrichment on DEA was examined in a saltmeadow cordgrass [Spartina patens (Aiton) Muhl.] marsh. In the high marsh, DEA significantly (p < 0.05) increased with watershed N loadings and decreased with the percent of hydric soils in a 200-m terrestrial buffer. In the low marsh, we found no significant relationships between DEA and watershed N loadings, residential land development, or terrestrial hydric soils. In the manipulation experiment, we measured increased DEA in N-amended treatments, but no effect in the P-amended treatments. The positive relationships between N loading and high marsh DEA support the hypothesis that salt marshes may be important buffers between the terrestrial landscape and estuaries, preventing the movement of land-derived N into coastal waters. The negative relationships between marsh DEA and the percent of hydric soils in the adjacent watershed illustrate the importance of natural buffers within the terrestrial landscape. Denitrification enzyme activity appears to be a useful index for comparing relative N exposure and the potential denitrification activity of coastal salt marshes. 相似文献
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In a previously published study, quantitative relationships were developed between landscape metrics and sediment contamination for 25 small estuarine systems within Chesapeake Bay. These analyses have been extended to include 75 small estuarine systems across the mid-Atlantic and southern New England regions of the USA. Because of the different characteristics and dynamics of the estuaries across these regions, adjustment for differing hydrology, sediment characteristics, and sediment origins were included in the analysis. Multiple linear regression with stepwise selection was used to develop statistical models for sediment metals, organics, and total polycyclic aromatic hydrocarbons (PAHs). The landscape metrics important for explaining the variation in sediment metals levels (R2 = 0.72) were the percent area of nonforested wetlands (negative contribution), percent area of urban land, and point source effluent volume and metals input (positive contributions). The metrics important for sediment organics levels (R2 = 0.5) and total PAHs (R2 = 0.46) were percent area of urban land (positive contribution) and percent area of nonforested wetlands (negative contribution). These models included silt-clay content (metals) or total organic C (organics, total PAHs) of sediments and grouping by estuarine hydrology, suggesting the importance of sediment characteristics and hydrology in mitigating the influence of the landscape metrics on sediment contamination levels. The overall results from this study are indicative of how statistical models can be developed relating landscape metrics to estuarine sediment contamination for distributions of land cover and point source discharges. 相似文献
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生态旅游是一项具有保护自然生态与文化多样性,提高旅游者环境意识及维护当地居民生活双重责任的旅游活动,具有较强的环境教育功能。但其功能的发挥不是旅游活动的自然结果,而有赖于人的自觉和切实有效的环境教育。本研究基于对生态旅游环境教育功能及其影响因素正确认识基础上,构建生态旅游环境教育功能实现的基本框架,并系统阐述环境解说、产品设计、舆论监督、宣传教育、环境管理等途径。本研究对促进生态旅游健康发展和国民环境教育具有重要意义。 相似文献
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Genevieve Briand Eric C. Schuck David W. Holland 《Journal of the American Water Resources Association》2008,44(2):360-366
Abstract: For over 10 years, several species of salmon have been identified as either threatened or endangered in the Snake River Basin of Idaho. The United States Bureau of Reclamation, in cooperation with the National Marine Fisheries Service, has proposed a variety of plans to increase stream flows in the Snake River Basin to facilitate movement by juvenile salmon smolts to the ocean. This research examines two of the flow augmentation plans proposed by the Bureau of Reclamation as well as two alternative plans, one founded purely on existing priority‐based water rights and another geared toward minimizing the effects of flow augmentations on farms profitability. Results from a basin‐wide model of agricultural production in the Snake River Basin, the Snake River Agricultural Model, present evidence that (1) older water rights are used towards production of less valuable crops, (2) flow augmentation scenarios have unequal effects on farms profitability across agricultural regions within the basin, and (3) irrigation water is valued from US$4 to US$59 an acre‐foot. 相似文献
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Jeremy Haggar Byron Medina Rosa Maria Aguilar Claudia Munoz 《Environmental management》2013,51(4):811-823
Changes in commodity prices, such as the fall in coffee prices from 2000 to 2004, affect land use decisions on farms, and the environmental services they provide. A survey of 50 farms showed a 35 % loss in the area under coffee between 2000 and 2004 below 700 m with the majority of this area (64 %) being coffee agroforest systems that included native forest species. Loss of coffee only occurred on large and medium-scale farms; there was no change in area on cooperatives. Coffee productivity declined below 1,100 m altitude for sun and Inga shade coffee, but only below 700 m altitude for agroforest coffee. Coffee productivity was 37–53 % lower under agroforests than other systems. Increases in rubber and pasture were related to low altitude large-scale farms, and bananas and timber plantations to mid-altitude farms. Average aboveground carbon stocks for coffee agroforests of 39 t C ha?1 was similar to rubber plantations, but one-third to one half that of natural forest and timber plantations, respectively. Coffee agroforests had the highest native tree diversity of the productive systems (7–12 species ha?1) but lower than natural forest (31 species ha?1). Conversion of coffee agroforest to other land uses always led to a reduction in the quality of habitat for native biodiversity, especially avian, but was concentrated among certain farm types. Sustaining coffee agroforests for biodiversity conservation would require targeted interventions such as direct payments or market incentives specifically for biodiversity. 相似文献
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Frank A. Ward Ari M. Michelsen Leeann DeMouche 《Journal of the American Water Resources Association》2007,43(1):237-253
Abstract: The Rio Grande basin shares problems faced by many arid regions of the world: growing and competing demands for water and river flows and uses that are vulnerable to drought and climate change. In recent years legislation, administrative action, and other measures have emerged to encourage private investment in efficient agricultural water use. Nevertheless, several institutional barriers discourage irrigators from investing in water conservation measures. This article examines barriers to agricultural water conservation in the Rio Grande basin and identifies challenges and opportunities for promoting it. Several barriers to water conservation are identified: clouded titles, water transfer restrictions, illusory water savings, insecure rights to conserved water, shared carry‐over storage, interstate compacts, conservation attitudes, land tenure arrangements, and an uncertain duty of water. Based on data on water use and crop production costs, price is found to be a major factor influencing water conservation. A low water price discourages water conservation even if other institutions promote it. A high price of water encourages conservation even in the presence of other discouraging factors. In conclusion, water‐conserving policies can be more effectively implemented where water institutions and programs are designed to be compatible with water’s underlying economic scarcity. 相似文献
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MICHAEL FISHER 《Natural resources forum》1985,9(2):97-105
A common barrier to undertaking conservation measures in developing countries is the limited ability or the reluctance of energy users to acquire and deploy the capital needed to develop these opportunities. Industrial firms, for example, have had frequent opportunities in recent years to benefit from the use of new, more energy-efficient production technologies, but insufficient internal cash, combined with an ability to raise debt or equity capital under favourable terms, have often prevented firms from funding these investments.
Confronted with such impediments to mobilizing capital for conservation investments, some financiers and entrepreneurs in industrialized countries have recently implemented five innovative arrangements for financing conservation and other energy-related investments. These five financing arrangements are discussed. For each arrangement, the structure and operation, the distribution of risk between the energy user and the creditors/external investors, and the financial benefits that accrue to the energy user are described. 相似文献
Confronted with such impediments to mobilizing capital for conservation investments, some financiers and entrepreneurs in industrialized countries have recently implemented five innovative arrangements for financing conservation and other energy-related investments. These five financing arrangements are discussed. For each arrangement, the structure and operation, the distribution of risk between the energy user and the creditors/external investors, and the financial benefits that accrue to the energy user are described. 相似文献
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Mathias J. Collins 《Journal of the American Water Resources Association》2009,45(2):279-290
Abstract: Long‐term flow records for watersheds with minimal human influence have shown trends in recent decades toward increasing streamflow at regional and national scales, especially for low flow quantiles like the annual minimum and annual median flows. Trends for high flow quantiles are less clear, despite recent research showing increased precipitation in the conterminous United States over the last century that has been brought about primarily by an increased frequency and intensity of events in the upper 10th percentile of the daily precipitation distribution – particularly in the Northeast. This study investigates trends in 28 long‐term annual flood series for New England watersheds with dominantly natural streamflow. The flood series are an average of 75 years in length and are continuous through 2006. Twenty‐five series show upward trends via the nonparametric Mann‐Kendall test, 40% (10) of which are statistically significant (p < 0.1). Moreover, an average standardized departures series for 23 of the study gages indicates that increasing flood magnitudes in New England occurred as a step change around 1970. The timing of this is broadly synchronous with a phase change in the low frequency variability of the North Atlantic Oscillation, a prominent upper atmospheric circulation pattern that is known to effect climate variability along the United States east coast. Identifiable hydroclimatic shifts should be considered when the affected flow records are used for flood frequency analyses. Special treatment of the flood series can improve the analyses and provide better estimates of flood magnitudes and frequencies under the prevailing hydroclimatic condition. 相似文献