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1.
Water quality criteria were developed for delivery waters to Everglades National Park. The park receives a minimum of 12.34 m3/sec (315,000 acre-ft/yr) of water from controlled sources external to its boundary. These waters often originate from areas that are or potentially are impacted from urban and agricultural developments. When, in 1970, the U.S. Congress guaranteed minimum water deliveries to Everglades National Park, it also required that these waters be of good quality.The Everglades National Park water quality data base was analyzed from 1970 to 1978 at both in-park and water delivery sites to determine the current level of delivery water quality and to select representative delivery sites. It was found that current delivery water quality was sufficiently high to be adopted as criteria against which future water quality could be compared. From the delivery sites S-12C and L-67A all data were combined from 1970–1978 for 36 parameters including macronutrients, heavy metals, and field parameters such as DO, pH, and specific conductance. Mean concentrations and upper limits were computed and tabulated for comparison during future monitoring programs. These criteria were subsequently adopted through a joint memorandum of agreement between the U.S. Army Corps of Engineers, South Florida Water Management District and the U.S. National Park Service.  相似文献   

2.
Everglades restoration is dependent on constructed wetlands to treat agricultural phosphorus (P)-enriched runoff prior to delivery to the Everglades. Over the last 5 years, P concentrations delivered to the northern boundary of Everglades National Park (Park) have remained higher than the 8 μg L?1-target identified to be protective of flora and fauna. Historically, Everglades hydrology was driven by rainfall that would then sheetflow through the system. The system is now divided into a number of large impoundments. We use sodium-to-calcium ratios as a water source discriminator to assess the influence of management and environmental conditions to understand why P concentrations in Park inflows remain higher than that of the target. Runoff from Water Conservation Area 3A (Area 3A) and canal water from areas north of Area 3A are two major sources of water to the Park, and both have distinct Na:Ca ratios. The P concentrations of Park inflows have decreased since the 1980s, and from June 1994 through May 2000, concentrations were the lowest when Area 3A water depths were the deepest. Area 3A depths declined following this period and P concentrations subsequently increased. Further, some water sources for the Park are not treated and are impeding concentration reductions. Promoting sheetflow over channelized flow and treating untreated water sources can work in conjunction with constructed wetlands to further reduce nutrient loading to the sensitive Everglades ecosystem.  相似文献   

3.
Recent appearance of cattail (Typha domingensis) within a southern Everglades slough—Upper Taylor Slough (Everglades National Park)—suggests ecosystem eutrophication. We analyze water quality, nutrient enrichment, and water management operations as potential drivers of eutrophication in Upper Taylor Slough. Further, we attempt to determine why surface water phosphorus, a parameter used commonly to monitor ecosystem health in the Everglades, did not serve as an early warning for eutrophication, which has broader implication for other restoration efforts. We found that surface water total phosphorus concentrations generally were below a 0.01 mg L−1 threshold determined to cause imbalances in flora and fauna, suggesting no ecosystem eutrophication. However, assessment of nutrient loads and loading rates suggest Upper Taylor Slough has experienced eutrophication and that continued total phosphorus loading through a point-source discharge was a major driver. These nutrient loads, combined with increases in hydroperiods, led to the expansion of cattail in Upper Taylor Slough. We recommend other metrics, such as nutrient loads, periphyton and arthropod community shifts, and sediment core analyses, for assessing ecosystem health. Monitoring surface water alone is not enough to indicate ecosystem stress.  相似文献   

4.
Sediment and nutrient concentrations in surface water in agricultural regions are strongly influenced by agricultural activities. In the Corn Belt, recent changes in farm management practices are likely to affect water quality, yet there are few data on these linkages at the landscape scale. We report on trends in concentrations of N as ammonium (NH(4)) and nitrate (NO(3)), soluble reactive phosphorus (SRP), and suspended sediment (SS) in three Corn Belt streams with drainage areas of 12 to 129 km(2) for 1994 through 2006. During this period, there has been an increase in conservation tillage, a decline in fertilizer use, and consolidation of animal feeding operations in our study watersheds and throughout the Corn Belt. We use an autoregressive moving average model to include the effects of discharge and season on concentrations, LOWESS plots, and analyses of changes in the relation between discharge and concentration. We found significant declines in mean monthly concentrations of NH(4) at all three streams over the 13-yr period, declines in SRP and SS in two of the three streams, and a decline in NO(3) in one stream. When trend coefficients are converted to percent per year and weighted by drainage, area changes in concentration are -8.5% for NH(4), -5.9% for SRP, -6.8% for SS, and -0.8% for NO(3). Trends in total N and P are strongly tied to trends in NO(3), SRP, and SS and indicate that total P is declining, whereas total N is not.  相似文献   

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6.
Food habits of white-tailed deer (Odocoileus virginianus) were examined from January to November 1984 via fecal-pellet analysis at Valley Forge National Historical Park (VFNHP), which represents an island habitat for deer surrounded by extensive urbanization, in southeastern Pennsylvania. In addition, use of fields by deer was compared to food habits. Herbaceous vegetation (forbs, leaves of woody plants, and conifer needles) was the predominant food type in all seasons except fall. Acorns and graminoids (grasses and sedges) were important food resources in fall and spring, respectively. Use of woody browse (twigs) was similar among seasons. Field use was relatively high during fall, winter without snow cover (<20 cm), and spring when food resources in fields were readily available. In contrast, use of fields was lowest in summer when preferred woodland foods were available and in winter with snow cover when food in fields was not readily accessible. Patterns of food-type use by deer at VFNHP indicate the year-round importance of nonwoody foods and field habitats to deer populations on public lands such as national parks in the northeastern United States.  相似文献   

7.
External threats to the environmental integrity of Glacier National Park, Montana, USA, fit into three categories: adverse land use practices adjacent to the Park, air pollution, and water pollution. This article identifies and evaluates the laws that Glacier National Park officials might rely upon to protect the Park against these external threats. The article also assesses the available scientific information relating to external threats, and it identifies additional information needed to establish a legal basis for challenging the threats.  相似文献   

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9.
Transportation infrastructure in national parks has historically been designed for the automobile. With more vehicles in the parks, visitors found themselves in circumstances more reminiscent of a city than a park. Traffic jams, overcrowding, illegal parking, horn honking, and idling vehicles became common, creating stress and contributing to air and noise pollution, the very things visitors were hoping to get away from. Park managers began searching for alternatives, including shuttle systems. Many national parks have implemented optional shuttle systems, but relatively few have completely closed roads to vehicles, transporting visitors on mandatory shuttles. Zion National Park instituted a mandatory shuttle system in May 2000 to relieve crowding and congestion in the main canyon and to protect natural resources. Taking a longitudinal approach, attributes of the shuttle (e.g., crowding, accessibility, freedom, efficiency, preference, and success) were assessed with experiential park factors (e.g., scenic beauty, naturalness, solitude, tranquility, air quality, and soundscape) in 2000, 2003, and 2010 by surveying shuttle-riding park visitors. While visitors initially reported a few reservations about the shuttle system, by 2003, the majority rated the system successful. Ratings of all shuttle-related variables, except crowding, improved over the decade. Improvements were greatest for freedom, accessibility, and efficiency. Multiple regression found overall shuttle success to be mediated by preference, freedom, accessibility, efficiency, and comfort. Experiential variables assessing park conditions followed a similar pattern, with improved ratings as the decade progressed. Results provide important insights into the visitor experience with mandatory alternative shuttle systems in national parks.  相似文献   

10.
As the number of marine protected areas (MPAs) is globally increasing, information is needed on the effectiveness of existing sites. Many protected area agencies however have limited resources and are unable to evaluate MPA effectiveness. An evaluation conducted entirely by the managing agency may also lack credibility. Long-term monitoring and evaluation programs should ideally offer opportunities for participation of diverse groups in the selection of evaluation indicators and their assessment. A participatory approach has the potential to enhance evaluation capacity, to increase credibility and acceptance of results, to strengthen relationships between managers and local stakeholders, and to address more locally relevant information. Using a case study approach, this paper investigates diverse stakeholder groups’ opinions on the design of an evaluation and their interest to participate in an assessment. Respondents were most interested in the assessment of MPA achievements and outcome indicators. Most groups identified a range of government agencies and stakeholders that should participate in an assessment but only half of all respondents were interested to participate in monitoring activities. Most frequently mentioned limitations for more participation were a lack of time and money, but also governance shortcomings such as limited participation possibilities and not paying enough credit to stakeholders’ input. Participation interest was also influenced by occupation, place of residency, and familiarity with the marine environment. Differences exist among stakeholders about suitable evaluators and preferred monitoring partners, which could affect the credibility of evaluation results and affect monitoring activities.  相似文献   

11.
Water samples from streams and springs in the Great Smoky Mountains National Park were analyzed for fecal coliform, fecal streptococcus, and total coliform bacteria. Levels of bacteria were found to be highly variable but related to elevation, time of year, type of water source, and water level of the streams. Visitors did not seem to be major contributors to bacterial contamination. Levels of fecal coliform and total coliform in most water samples were unsuitable for drinking without treatment. Tennessee state standards for body contact recreation (swimming and wading) were exceeded in a few samples but none from streams suitable for swimming. As a result of these findings, park managers increased efforts to inform visitors of the need to treat drinking water and removed improvements at backcountry springs which tended to give the springs the image of safe, maintained water sources.  相似文献   

12.
Madhupur National Park is renowned for severe resource ownership conflicts between ethnic communities and government authorities in Bangladesh. In this study, we applied the Institutional Analysis and Development framework to identify: (i) past and present informal institutional structures within the ethnic Garo community for land resource management; (ii) the origin of the land ownership dispute; (iii) interaction mechanisms between formal and informal institutions; and (iv) change in land management authority and informal governance structures. We identify that the informal institutions of the traditional community have undergone radical change due to government interventions with implications for the regulation of land use, informal institutional functions, and joint-decision-making. Importantly, the government’s persistent denial of the role of existing informal institutions is widening the gap between government and community actors, and driving land ownership conflicts in a cyclic way with associated natural resource degradation.  相似文献   

13.
This study assessed campsite conditions and the effectiveness of campsite impact management strategies at Isle Royale National Park, USA. Protocols for assessing indicators of vegetation and soil conditions were developed and applied to 156 campsites and 88 shelters within 36 backcountry campgrounds. The average site was 68 m2 and 83% of sites lost vegetation over areas less than 47 m2. We believe that management actions implemented to spatially concentrate camping activities and reduce camping disturbance have been highly successful. Comparisons of disturbed area/overnight stay among other protected areas reinforces this assertion. These reductions in area of camping disturbance are attributed to a designated site camping policy, limitation on site numbers, construction of sites in sloping terrain, use of facilities, and an ongoing program of campsite maintenance. Such actions are most appropriate in higher use backcountry and wilderness settings.  相似文献   

14.
In Rocky Mountain National Park (RMNP), aspen (Populus tremuloides Michx.) has been observed to be declining on elk (Cervus elaphus nelsoni) winter range for many decades. To support elk management decisions, the SAVANNA ecosystem model was adapted to explore interactions between elk herbivory and aspen dynamics. The simulated probability of successful vegetative regeneration for senescent aspen stands declines sharply when elk densities reach levels of 3–5 elk/km2, depending on model assumptions for the seasonal duration of elk foraging activities. For aspen stands with a substantial component of younger trees, the simulated regeneration probability declines more continuously with increasing elk density, dropping below 50% from densities at 8–14 elk/km2.At the landscape scale, simulated aspen regeneration probability under a scenario of extensive seasonal use was little affected by elk population level, when this level was above 300–600 elk (25%–50% current population) over the ca. 107 km2 winter range. This was because elk distribution was highly aggregated, so that a high density of elk occupied certain areas, even at low population levels overall. At approximately current elk population levels (1000–1200 elk), only 35%–45% of senescent aspen stands are simulated as having at least a 90% probability of regeneration, nearly all of them located on the periphery of the winter range. Successful management for aspen persistence on core winter range will likely require some combination of elk population reduction, management of elk distribution, and fencing to protect aspen suckers from elk browsing.  相似文献   

15.
Available information on the socioeconomic implications of marine protected areas (MPAs) for the socioculturally diverse Mediterranean region is scant. The National Marine Park of Alonissos, Northern Sporades (NMPANS), Greece was established in 1992 as a foundation for the conservation of the endangered Mediterranean monk seal Monachus monachus. The evolution of the degree of acceptance of and satisfaction from the NMPANS by involved stakeholder groups (fishermen, tourism operators, hoteliers and owners of rooms to let, governmental bodies, nongovernmental bodies, students, domestic and foreign tourists) were investigated 13 years after its establishment using written questionnaires delivered during personal interviews. The initial positive attitude of local professionals for the NMPANS has eroded due to the unsatisfactory fulfillment of expectations for socioeconomic development. Fishermen expressed dissatisfaction with, mistrust toward, and a reluctancy to communicate with the NMPANS’s management body. They believe that the fishery areas have decreased in actual geographic area because of the prohibitive measures; fish stocks are declining; compensation for damage to fishery equipment by the Mediterranean monk seal and for the prohibitive measures should be provided; and stricter enforcement of regulations should take place. On the other hand, tourism operators, who organize trips for tourists to the NMPANS, unanimously reported direct economic benefits. Furthermore, there was a disparity in the perception of socioeconomic benefits derived from the NMPANS between governmental bodies and local stakeholders. The governmental bodies and the nongovernmental organization MOm-Hellenic Society for the Study and Protection of the Monk Seal postulated that there had been considerable socioeconomic benefits for the local community of Alonissos due to the establishment of the NMPANS, whereas the local nongovernmental organization Ecological and Cultural Movement of Alonissos claimed benefits were scant. Tourists (domestic and foreign) believe that the NMPANS is not the main attraction to Alonissos Island but is part of a composite, including serenity, aesthetic beauty, and small-scale tourism development, which can turn Alonissos Island into an ideal eco-tourism destination; a common aspiration for both the tourists and the local community by general consensus. The aim of the NMPANS to integrate conservation and development lies in (1) the effectiveness of the NMPANS management body in formulating a strategic management plan that would accommodate stakeholders’ interests and aspirations and (2) a national policy of conservation and enhancement of natural resources with consistency and continuity. Quantitative assessment of the socioeconomic effectiveness of the Mediterranean MPAs using a common methodology would facilitate the identification of intraregional variation and better planning for the network of MPAs in the Mediterranean.  相似文献   

16.
Summary Prespa National Park is situated at the northwestern corner of Greece bordering Yugoslavia and Albania and covers 25,690 ha of which 8,114 ha are lake. The remaining area is forest, rangeland and arable land in the vicinity of twelve villages. The objectives of the park authority are to preserve the wetland with its special fauna of rare bird species, its flora, the geomorphological formations of the lake and the natural environment. The nucleus of the park is comprised by Lake Mikri Prespa and the surrounding wetland. It is in this wetland that an exceptional assemblage of rare and endangered species breed. However, the park is recently undergoing rapid development of its agroecosystems in terms both of higher subsidiary energy inputs, notably irrigation, and of acreage, i.e. of substituting some of the wetland for cropland. The objective of this study was to assess the potential environmental hazards from practicing agriculture in the park and to propose measures of abatement. Assessment was based on field surveys, administration documents and interviews. Cropland is not intensively used at present. Two thirds is covered by winter cereals and the remaining by other row crops (beans and potatoes). There are no deciduous orchards. Practices are carried out without regard for environmental conservation. Farmers' attitudes towards the wildlife range from indifference to hostility because they attribute the lag in their economic development to the past restrictions imposed by the National Park Administration. The main environmental consequences from the ongoing agricultural development in Prespa are assessed to be a dramatic increase of nonpoint agricultural pollution of the lake, with phosphorus and pesticides as the primary pollutants. Moreover, accidents in the use of pesticides may lead to immediate deterioration of the nucleus wildlife habitats. Since irrigated agroecosystems are there to stay and grow in subsidiary energy, measures are needed to prevent harmful consequences. Such measures are the alleviation of the land ownership problem, adoption of cultural practices to limit soil erosion, rational use of chemical fertilizers and pesticides and education of farmers. It is concluded that the internationally invaluable natural ecosystems of the park are definitely threatened by the development of the irrigated agroecosystems. The measures proposed will limit this threat and at the same time will help to perpetuate the productivity of the agroecosystems themselves.Mrs. M. D. Pyrovetsi is a lecturer in the Department of Biology and Professor P. A. Gerakis is Head of the Department of Agriculture; both are within the Aristotle University of Thessaloniki, Greece.  相似文献   

17.
The administration of Jiuzhaigou National Park in Sichuan Province, China, is in the process of considering a range of upgrades to their sanitation and wastewater treatment systems. Their case history involves an ongoing series of engineering design flaws and management failures. The administration of the Park identified sustainability, environmental protection, and education goals for their sanitation and wastewater treatment system. To meet the goal of sustainability, environmental and economic concerns of the Park’s administration had to be balanced with socio-cultural needs. An advanced reconnaissance method was developed that identified reasons for previous failures, conducted stakeholder analysis and interviews, determined evaluation criteria, and introduced innovative alternatives with records of successful global implementations. This evaluation also helped the Park to better define their goals. To prevent future failures, the administration of the Park must commit to a balanced and thorough evaluation process for selection of a final alternative and institute effective long-term management and monitoring of systems. In addition, to meet goals and achieve energy efficient, cost-effective use of resources, the Park must shift their thinking from one of waste disposal to resource recovery. The method and criteria developed for this case study provides a framework to aid in the successful implementation of sanitation projects in both underdeveloped and developed areas of the world, incorporating socio-cultural values and resource recovery for a complex group of stakeholders.  相似文献   

18.
Past on-site experience was linked to the crowding perceptions and use displacement of 383 on-site visitors to the peri-urban Danube Floodplains National Park, Austria. Three visitor groups were determined according to their area experience: local residents from Vienna and rural communities, having the highest level of experience; regional visitors from the city and eastern Austria; and tourists from Austria and abroad with the lowest degree of experience. Crowding perceptions were significantly different across the user groups. More than 50% of local residents perceived the national park as crowded, whereas only 27% of regional visitors and 19% of tourists reported such an evaluation. Even among local residents and regional visitors, respondents with more on-site experience expressed a greater impression of a crowded park. Differences in crowding evaluations between local rural and urban residents and between regional rural and urban visitors were not found. For 27% of local residents and 15% of regional visitors, use levels were so unacceptable that they displaced temporally and spatially, whereas use displacement was relatively irrelevant for tourists. The use displacement strategies involved differ among the three user groups. Management implications were discussed, taking the specific situation of the small national park on the urban-rural fringe into consideration.  相似文献   

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20.
《中国环保产业》2005,(10):10-10
序号 产品名称 获证单位 证书号 有效期 管式阻性消声器.阻抗复合式消声器.阻 性片式消声器.双层微孔板消声器T701- 200 x 200.T701一6一400x400.ZP- 40()x40().SK一11一400x400 北京市华通嘉业空调设备有限责任公司 CCAEPI一EP一2{X)5一070 2005年8月一2008年8月 7 1 QJXIO17一2型汽油车排气催化转化器(OEM) 山西净土实业有限公司 CCAEPI一EP一2005一071 2005年9月一加07年12月 Y卜JWSJO·JD型复合式饮食业油烟净化设备 【风摄(m,爪):》2000一‘200001 广州市兴华环保设备联合有限公司 CCAEPI一EP一20(]5一072 2005年9…  相似文献   

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