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1.
Summary The careful integration of tourism/leisure activities with agriculture is proving of increasing economic value to farming communities whilst providing also the means to safeguard and conserve rural environments and landscapes. The recognition of this value is reflected in the number of grants available in Europe to assist and encourage farmers to diversify their farming activities to embrace tourism and leisure. This paper describes a number of schemes which have been promoted in the Peak National Park (UK) to encourage farmers to attempt such diversification. Their value in conserving a valuable and valued landscape is discussed.Haydon Morris was until recently Senior Planner at the Peak National Park, and is currently Development Manager for the Cumbria Tourist Board. He may be contacted at the Board's Offices; Ashleigh, Windermere, LA23 2AQ, UK.Dr Michael Romeril is Conservation Officer for the Island of Jersey. His address is; Planning Office, South Hill, St. Helier, Jersey, G.B.  相似文献   

2.
ABSTRACT. In urban hydrologic studies, it is often necessary to determine the effect of changes in urban land use patterns on such runoff characteristics as flood peaks and flow volumes. Nonparametric statistical methods have certain properties that make them a valuable tool for detecting hydrologic change caused by a treatment, such as urbanization, that changes watershed over a period of time. As many hydrologists do not have a working familiarity with nonparametric methods, a number of them are used for illustrative purposes to analyze the effect of urbanization on 24 years of annual flood peaks for a Louisville, Kentucky, watershed. In the example, urbanization was found to increase the central tendency, but not the dispersion of the peaks. Peak flows modeled by holding watershed parameters constant were also found to be increasing because of an upward trend in precipitation. By following the numerical examples in the paper and looking up test statistics in referenced sources, the reader can easily apply these methods to other situations.  相似文献   

3.
Arthropods constitute well over one-half of the species of higher life on the planet and are the dominant terrestrial life form on the planet. Unfortunately, very little is known about most arthropod species. There are an estimated 163,487 species of insects in North America, of which only 66% are taxonomically known. Similarly, there are an estimated 35,514 species of North American arachnids, of which only 9316 are described; over 73% have yet to be discovered and described. Without the basic taxonomic and life history knowledge for most of the terrestrial species (i.e., arthropods) of North American ecosystems, land managers are faced with the challenge of developing, selecting, and managing biotic reserves and habitat conservation plans for which they know very little about the majority of organisms found within such reserves or covered by such plans. With respect to arthropods, this challenge includes taking into account poorly described species being used as political tools to stop development (as opposed to actually protecting a truly endangered species), thus confounding the habitat conservation planning process and ensuring that "surprises" in the form of new listings will occur within any multispecies habitat plan. Finally, using various scenarios and assumptions, estimates of the true number of endangered insects and arachnids are provided to illustrate the fact that the suspected number of threatened, endangered, and extinct species is probably low by at least an order of magnitude.  相似文献   

4.
The EPA’s new nonpoint source pollution control requirements will soon institutionalize urban erosion and sediment pollution control practices nationwide. The public and private sector costs and social benefits associated with North Carolina’s program (one of the strongest programs in the country in terms of implementation authority, staffing levels, and comprehensiveness of coverage) are examined to provide general policy guidance on questions relating to the likely burden the new best management practices will have on the development industry, the likely costs and benefits of such a program, and the feasibility of running a program on a cost recovery basis. We found that urban erosion and sediment control requirements were not particularly burdensome to the development industry (adding about 4% on average to development costs). Public-sector program costs ranged between $2.4 and $4.8 million in fiscal year 1989. Our contingent valuation survey suggests that urban households in North Carolina are willing to pay somewhere between $7.1 and $14.2 million a year to maintain current levels of sediment pollution control. Our benefit-cost analysis suggests that the overall ratio is likely to be positive, although a definitive figure is elusive. Lastly, we found that several North Carolina localities have cost recovery fee systems that are at least partially self-financing. This article is based on research by the authors for the North Carolina Department of Environment, Health and Natural Resources (DEHNR). The views are those of the research team and do not necessarily reflect the position of DEHNR.  相似文献   

5.
ABSTRACT There are several possible ways in which wastewater from municipalities may be reclaimed and reused so as to minimize the need for imported water in North Central Texas. The rationale for reuse is enhanced by the fact that new water quality requirements in the Trinity River system will necessitate a very high degree of treatment at municipal sewage plants, just for discharge to surface streams. The largest potential market for municipal effluent is the steam-electric power industry. Within the next decade the generating capacity for electric power in North Central Texas will have to be more than doubled to meet increasing demand. Adequate supplies of condenser cooling water for such expansion will be difficult to obtain and assure. New large power stations might advantageously be located adjacent to municipal wastewater treatment plants, to utilize effluent as make-up water for cooling towers. Experience elsewhere has shown that well-treated wastewater can be used for cooling tower make-up with a minimum of trouble, with a considerable saving in overall cost, and with conservation of pristine water for other uses.  相似文献   

6.
ABSTRACT: The environmental setting of the Red River of the North basin within the United States is diverse in ways that could significantly control the areal distribution and flow of water and, therefore, the distribution and concentration of constituents that affect water quality. Continental glaciers shaped a landscape of very flat lake plains near the center of the basin, and gently rolling uplands, lakes, and wetlands along the basin margins. The fertile, black, fine-grained soils and landscape are conducive to agriculture. Productive cropland covers 66 percent of the land area. The principal crops are wheat, barley, soybeans, sunflowers, corn, and hay. Pasture, forests, open water, and wetlands comprise most of the remaining land area. About one-third of the 1990 population (511,000) lives in the cities of Fargo and Grand Forks, North Dakota and Moorhead, Minnesota. The climate of the Red River of the North basin is continental and ranges from dry subhumid in the western part of the basin to subhumid in the eastern part. From its origin, the Red River of the North meanders northward for 394 miles to the Canadian border, a path that is nearly double the straight-line distance. The Red River of the North normally receives over 75 percent of its annual flow from the eastern tributaries as a result of regional patterns of precipitation, evapotranspiration, soils, and topography. Most runoff occurs in spring and early summer as a result of rains falling on melting snow or heavy rains falling on saturated soils. Lakes, prairie potholes, and wetlands are abundant in most physiographic areas outside of the Red River Valley Lake Plain. Dams, drainage ditches, and wetlands alter the residence time of water, thereby affecting the amount of sediment, biota, and dissolved constituents carried by the water. Ground water available to wells, streams, and springs primarily comes from sand and gravel aquifers near land surface or buried within 100 to 300 feet of glacial drift that mantles the entire Red River of the North basin. Water moves through the system of bedrock and glacial-drift aquifers in a regional flow system generally toward the Red River of the North and in complex local flow systems controlled by local topography. Many of the bedrock and glacial-drift aquifers are hydraulically connected to streams in the region. The total water use in 1990, about 196 million gallons per day, was mostly for public supply and irrigation. Slightly more than one half of the water used comes from ground-water sources compared to surface-water sources. Most municipalities obtain their water from ground-water sources. However, the largest cities (Fargo, Grand Forks and Moorhead) obtain most of their water from the Red River of the North. The types and relative amounts of various habitats change among the five primary ecological regions within the Red River of the North basin. Headwater tributaries are more diverse and tend to be similar to middle-reach tributaries in character rather than the lower reaches of these tributaries for the Red River of the North. Concentrations of dissolved chemical constituents in surface waters are normally low during spring runoff and after thunderstorms. The Red River of the North generally has a dissolved-solids concentration less than 600 milligrams per liter with mean values ranging from 347 milligrams per liter near the headwaters to 406 milligrams per liter at the Canadian border near Emerson, Manitoba. Calcium and magnesium are the principal cations and bicarbonate is the principal anion along most of the reach of the Red River of the North. Dissolved-solids concentrations generally are lower in the eastern tributaries than in the tributaries draining the western part of the basin. At times of low flow, when water in streams is largely from ground-water seepage, the water quality more reflects the chemistry of the glacial-drift aquifer system. Ground water in the surficial aquifers commonly is a calcium bicarbonate type with dissolved-solids concentration generally between 300 and 700 milligrams per liter. As the ground water moves down gradient, dissolved-solids concentration increases, and magnesium and sulfate are predominant ions. Water in sedimentary bedrock aquifers is predominantly sodium and chloride and is characterized by dissolved-solids concentrations in excess of 1,000 milligrams per liter. Sediment erosion by wind and water can be increased by cultivation practices and by livestock that trample streambanks. Nitrate-nitrogen concentrations also can increase locally in surficial aquifers beneath cropland that is fertilized, particularly where irrigated. Nitrogen and phosphorous in surface runoff from cropland fertilizers and nitrogen from manure can contribute nutrients to lakes, reservoirs, and streams. Some of the more persistent pesticides, such as atrazine, have been detected in the Red River of the North. Few data are available to conclusively define the presence or absence of pesticides and their break-down products in Red River of the North basin aquifers or streams. Urban runoff and treated effluent from municipalities are discharged into streams. These point discharges contain some quantity of organic compounds from storm runoff, turf-applied pesticides, and trace metals. The largest releases of treated-municipal wastes are from the population centers along the Red River of the North and its larger tributaries. Sugar-beet refining, potato processing, poultry and meat packing, and milk, cheese, and cream processing are among the major food processes from which treated wastes are released to streams, mostly in or near the Red River of the North.  相似文献   

7.
Global Earth Observation (GEO) is one of the most important sources of information for environmental resource management and disaster prevention. With budgets for GEO increasingly under pressure, it is becoming important to be able to quantify the returns to informational investments. For this, a clear analytical framework is lacking. By combining Bayesian decision theory with an empirical, stakeholder-oriented approach, this paper attempts to develop such a framework. The analysis focuses on the use of satellite observations for Dutch water quality management in the North Sea. Dutch water quality management currently relies on information from 'in situ' measurements but is considering extending and deepening its information base with satellite observations. To estimate returns to additional investments in satellite observation, we analyze the added value of an extended monitoring system for the management of eutrophication, potentially harmful algal blooms and suspended sediment and turbidity in the North Sea. First, we develop a model to make the potential contribution of information to welfare explicit. Second, we use this model to develop a questionnaire and interpret the results. The results indicate that the expected welfare impact of investing in satellite observation is positive, but that outcomes strongly depend on the accuracy of the information system and the range of informational benefits perceived.  相似文献   

8.
Abstract Many prairie potholes in North Dakota are filled with emergent aquatic vegetation. The paper describes briefly how evapotranspiration losses were determined for such potholes using a mass-transfer equation in which the coefficient was evaluated by means of a water budget. Vegetation, by its presence, reduces evaporation below the normal from a free water surface so much that the total seasonal (May - October) evapotranspiration loss is less than the normal evaporation loss from a pothole clear of vegetation.  相似文献   

9.
This paper examines the process of establishing a coastal forum in the North West region of England. The North West Coastal Forum is one of the first attempts at the establishment of a regional forum in England and is especially notable for the role played by the Government Office for the North West in its formation. The paper examines the relationships between the key agencies involved and, in particular, the key role played by the Government Office for the North West in promoting and establishing the forum and how this has influenced its organization, structure and composition. It provides a critical analysis of the apparent and potential strengths and weaknesses of the forum as an example of a partnership approach to the planning and management of coastal issues in the North West. The conclusions are not only of relevance to the future development of the forum within the North West of England, and to the potential establishment of similar coastal fora elsewhere, but are also of much broader interest as a case example of the development of institutional capacities and collaborative partnership approaches to planning issues at the regional level in the wider context of the changing nature of regional governance in the UK and the enhanced 'regional partnership' role being embraced by the government offices for the regions.  相似文献   

10.
This paper examines the problems Inherent in identifying and measuring infrastructure-related subsidies associated with 'greenfield' natural resource projects. The findings suggest that even if external benefits and costs are ignored, and a market-oriented estimation process is adopted, substantial problems still face policy analysts attempting to measure the extent to which such projects have been subsidized. This conclusion is demonstrated through a detailed examination of the Canadian-based North East British Columbia coal project.  相似文献   

11.
A conceptual mathematical model has recently been devised to assist environmental managers in predicting the impact on coastal marsh areas of long-term changes in water levels. The model considers such impact solely in terms of the geometry of the confining basin, the change in ambient water level, and the maximum depth for which bottom-rooted emergent vegetation is present. This model is applied to 17 shoreline marshes of various shapes in the Georgian Bay/North Channel region of the Great Lakes.Model outputs of predicted maximum and minimum marsh area subsequent to changes in long-term levels are compared to marsh areas measured from available historical air photos dating from 1935 to 1985. The results of such comparisons indicate that such a geometric model, despite its neglect of the biological complexities of marsh ecology, can serve as a valuable tool for assessing the range of impacts of both natural and man-made changes in long-term ambient water levels on shoreline marshes.  相似文献   

12.
OHS风险控制方法在烟气排放控制工程中的应用   总被引:1,自引:0,他引:1  
介绍了烟气排放控制工程中OHS风险控制的方法,并以香港青山“B”电厂4X680MW机组排放控制工程(CPBEC)为例,阐述了目前国内外环保项目在OHS风险管理方面的差距和改进措施。  相似文献   

13.
In some high-fertility, high-stocking-density grazing systems, nitrate (NO(3)) leaching can be great, and ground water NO(3)-N concentrations can exceed maximum contaminant levels. To reduce high N leaching losses and concentrations, alternative management practices need to be used. At the North Appalachian Experimental Watershed near Coshocton, OH, two management practices were studied with regard to reducing NO(3)-N concentrations in ground water. This was following a fertilized, rotational grazing management practice from which ground water NO(3)-N concentrations exceeded maximum contaminant levels. Using four small watersheds (each approximately 1 ha), rotational grazing of a grass forage without N fertilizer being applied and unfertilized grass forage removed as hay were used as alternative management practices to the previous fertilized pastures. Ground water was sampled at spring developments, which drained the watershed areas, over a 7-yr period. Peak ground water NO(3)-N concentrations before the 7-yr study period ranged from 13 to 25.5 mg L(-1). Ground water NO(3)-N concentrations progressively decreased under each watershed and both management practices. Following five years of the alternative management practices, ground water NO(3)-N concentrations ranged from 2.1 to 3.9 mg L(-1). Both grazing and haying, without N fertilizer being applied to the forage, were similarly effective in reducing the NO(3)-N levels in ground water. This research shows two management practices that can be effective in reducing high NO(3)-N concentrations resulting from high-fertility, high-stocking-density grazing systems, including an option to continue grazing.  相似文献   

14.
朱智媛 《四川环境》2009,28(2):48-51
人工湿地处理技术具有投资低、出水水质好、耗能低、抗冲击力强、操作简单和运行费用低等优点。本文阐述了人工湿地系统应用于高校生活污水回收利用的意义,以福建工程学院新校区的北校区为例,利用前期在福州大学模拟人工湿地系统处理生活污水的实验数据,规划设计人工湿地系统,计算确定相关设施的面积和尺寸,并对人工湿地系统进行平面布置,绘制出系统流程的剖面图。  相似文献   

15.
ABSTRACT. The occurrence of ground water in the lower North Platte Valley, Goshen County, Wyoming, was studied to determine safe yield within the alluvial aquifer under varying discharge and recharge conditions. The alluvium of the North Platte is extensively developed for irrigation purposes and the effects of large-scale pumpage are of major concern. Actual withdrawals are estimated to be 46,000 acre-feet. Should pumping reach potentially higher levels an overdraft is expected. Effect of ground water withdrawals are established from projections of the flow regime within the alluvial aquifer. A time dependent, numerical model was employed to predict aquifer response to increased withdrawals. The results suggest that more efficient use of surface waters and/or increased use of ground water will reduce the annual subsurface return flow to the North Platte River and its tributaries by an amount equal to the reduced ground water recharge increment. Alternatives are available for management of the lower North Platte alluvial aquifer. The preferred course is to correlate surface and subsurface water rights, in light of convenience, economics, and best means of storage for maximum utilization of the single water resource.  相似文献   

16.
粤北地区芳香植物资源及其综合利用对策   总被引:1,自引:0,他引:1  
粤北地区芳香植物资源丰富.经调查统计,该地区的芳香种子植物有105科240属470种(含种以下等级),分别占该地区所有种子植物科、属、种的54.6%、28.9%、20%.区系成分分析结果显示,该地区芳香植物以热带亚热带成分为主,多种成分并存;优势科较显著,如樟科、芸香科、菊科、伞形科、木兰科、金缕梅科等.作者认为应采取一系列有效措施,对本地区芳香植物资源进行综合开发利用.  相似文献   

17.
以秦皇岛市北港镇长桥岭村的旅游开发为例,立足该村的发展状况和资源情况,提出开发以城市周边市民为主要对象的经济作物采摘、农家乐等整合模式旅游项目,并且联合周边旅游资源,打通秦皇岛北部"旅游带",提出了突破季节局限的旅游项目开发模式。  相似文献   

18.
Infrastructure intended to serve the public good frequently has implications for environmental justice and social sustainability. Drinking water supplies for sub/urban areas in North Carolina, USA, have regularly been secured by constructing dams to impound reservoirs. We used high-resolution, publicly available US Census data to explore whether 66 such reservoirs in North Carolina have induced demographic shifts in the communities that find themselves adjacent to the newly created lakeshores. Our principal findings include: (1) The ratio of white people to non-white people was significantly higher in communities within 0.5 miles of reservoir shorelines than in more distant communities; (2) even as North Carolina overall became less white from 1990 to 2010, the ratio of white people to non-white people within the 0.5 miles of the shoreline increased relative to the overall ratio in the State; and (3) similar, but less distinct, shifts in per capita income occurred during the period. Our results are consistent with the proposition that reservoirs have induced demographic shifts in communities adjacent to newly created lakeshores similar to the shifts associated with environmental gentrification and amenity migration, and may now be associated with perpetuating those shifts. These findings raise concerns about environmental justice and social sustainability that should be considered when planning and building infrastructure that creates environmental amenities. Where reservoirs are being planned, social costs, including the costs of demographic shifts associated with environmental gentrification or amenity migration, and disproportionate regulatory burdens, should be mitigated through innovative policy if possible.  相似文献   

19.
Abstract: In 2002, China launched the South‐to‐North Water Transfer Project after completing a 50‐year feasibility study. By 2050, the three‐route (i.e., East, Middle, and West) project will be capable of transferring 44.8 billion m3/year of water from the water rich Yangtze River to the arid north to alleviate water shortage and help secure a balanced social and economic development across the nation. However, diversion of such a large quantity of water could profoundly change the riverine environment of the upper Yellow River and the lower reach of the Han River, a tributary of the Yangtze River and the water supplying area of the project’s Middle Route, because of changes in the annual discharge. Secondary salinization seems inevitable in the water receiving areas of the North China Plain, and decrease in the discharge of the Yangtze River will result in seawater intrusion into the Yangtze Delta. This paper describes the project and discusses its environmental implications. Additionally, a long‐term monitoring strategy under the umbrella of the Chinese Ecological Research Network is proposed for environmental monitoring.  相似文献   

20.
ABSTRACT

In 2009 the Desertec Industrial Initiative (DII) was founded by several, predominant German enterprises. The objective of DII was to organise the conditions for the realisation of the Desertec idea, which aimed to both (a) supply Europe, in a large-scale manner, with electricity produced in solar power plants in North Africa and the Arabic peninsula and (b) contribute to the self-supply of the Middle East North Africa region (MENA). Protagonists of the desert energy idea saw this megatechnic project as a starting point for a new trans-Mediterranean EU-MENA union, critics in contrast as a neo-colonial project. Disputes over the adequate interpretation and implementation of the Desertec idea broke out from the beginning. In 2014/2015, the media talked of the failure of DII and of the Desertec concept. The majority of the members left DII at the end of 2014. On the other hand, in some MENA countries renewables are playing a crucial role in securing the future of the energy sector. This paper analyses the development of DII and the Desertec idea by using concepts from Social Studies in Technology, and especially by the multi-level perspective approach in Transition Studies. It shows how the interplay of different factors, such as technological developments, entrepreneurial performances and political processes, lead to internal conflicts and the non-realisation – up to now – of related large-scale energy projects. As an important aspect of the paper, different understandings of the future of our energy supply and of North–South relations are presented in detail.  相似文献   

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