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1.
Through their powers to regulate land use and their responsibilities for public water supply, local governments are critical players in groundwater protection. Unfortunately, the demands of groundwater protection are high, and many local governments do not have the ability or capacity to develop and implement appropriate management strategies. This paper analyzes groundwater protection experiences on Long Island, New York, a place where groundwater dependence is high, and threats to groundwater are serious. Long Island's experiences highlight the need to approach capacity building for groundwater protection broadly, concentrating on factors such as political commitment and citizen support; enhancement of local technical competency through linkages and support from state and federal governments; and strengthening of institutional arrangements at all levels.  相似文献   

2.
The effects of off-road vehicles (ORVs) on the dune system of Fire Island National Seashore, New York, USA, were examined through a detailed, two-year field study. The experimental approach was adopted in order to evaluate the environmental effects of ORVs in this zone. Adjacent control and impact sites were established in two locations. Vehicle impacts were applied at the equivalent rate of one vehicle pass per week. Monitoring of foredune vegetation through sequential quadrat surveys and construction of sea-ward limit maps showed a significant loss of vegetation resulting from ORV impacting. Loss of vegetation resulted in an alteration of the natural foredune profile, which could increase dune erosion during storm wave attack.  相似文献   

3.
Abstract: The residents of Nassau County Long Island, New York receive all of their potable drinking water from the Upper Glacial, Jameco/Magothy (Magothy), North Shore, and Lloyd aquifers. As the population of Nassau County grew from 1930 to 1970, the demand on the ground‐water resources also grew. However, no one was looking at the potential impact of withdrawing up to 180 mgd (7.9 m3/s) by over 50 independent water purveyors. Some coastal community wells on the north and south shores of Nassau County were being impacted by saltwater intrusion. The New York State Legislature formed a commission to look into the water resources in 1972. The commission projected extensive population growth and a corresponding increase in pumping resulting in a projected 93.5 to 123 mgd (4.1 to 5.5 m3/s) deficit by 2000. In 1986, the New York Legislature passed legislation to strengthen the well permit program and also establish a moratorium on new withdrawals from the Lloyd aquifer to protect the coastal community’s only remaining supply of drinking water. Over 30 years has passed since the New York Legislature made these population and pumping projections and it is time to take a look at the accuracy of the projections that led to the moratorium. United States Census data shows that the population of Nassau County did not increase but decreased from 1970 to 2000. Records show that pumping in Nassau County was relatively stable fluctuating between 170 and 200 mgd (7.5 to 8.8 m3/s) from 1970 to 2004, well below the projection of 242 to 321 mgd (10.6 to 14.1 m3/s). Therefore, the population and water demand never grew to projected values and the projected threat to the coastal communities has diminished. With a stable population and water demand, its time to take a fresh look at proactive ground‐water resource management in Nassau County. One example of proactive ground‐water management that is being considered in New Jersey where conditions are similar uses a ground‐water flow model to balance ground water withdrawals, an interconnection model to match supply with demand using available interconnections, and a hydraulic model to balance flow in water mains. New Jersey also conducted an interconnection study to look into how systems with excess capacity could be used to balance withdrawals in stressed aquifer areas with withdrawals in unstressed areas. Using these proactive ground‐water management tools, ground‐water extraction could be balanced across Nassau County to mitigate potential impacts from saltwater intrusion and provide most water purveyors with a redundant supply that could be used during water emergencies.  相似文献   

4.
This paper summarizes research evaluating nitrate levels in shallow groundwater of upstate New York, USA. Water from abandoned dug wells in six different land-use categories was analyzed for nitrate. Findings indicate that regardless of overlying land-use, shallow groundwater is susceptible to high levels of nitrate. Over 60 percent of the water samples tested, including at least one sample from each land-use category, had nitrate levels in excess of the United States drinking water standard of 10 mg 1–1. Due to the potential threat of elevated nitrate levels, efforts should be made to eliminate abandoned dug wells in shallow groundwater as a source of water supply.Glenn Harris is with the Environmental Studies Programme of St Lawrence University in Canton, New York. Brian Henry is with the Department of Entomology at the University of Georgia in Athens, Georgia. Jeffrey Deyette is with the joint International Relations and Resource and Environmental Management Programme at Boston University in Boston, Massachusetts. This research was performed as a Community Service Project sponsored by the Mergardt Fund while Mr Henry and Mr Deyette were students under the supervision of Dr Harris at St Lawrence University.  相似文献   

5.
This study compares the effectiveness of two regional planning agencies in terms of public support for various planning activities. The Adirondack Park Agency and the Temporary State Commission on Tug Hill have fundamentally different approaches to planning. The Adirondack Park Agency has implemented a restrictive regulatory program with little citizen participation by Adirondack residents. The Tug Hill Commission has implemented an advisory and coordinating program with an emphasis on public input. Residents of two towns in each region were surveyed to determine environmental concern and support for regional planning activities. Respondents from both regions favored a planning agency that incorporates citizen input; controls air, water, and toxic waste pollution; and develops recreation areas. They strongly opposed an agency that regulates private land-use. Basic demographic characteristics and levels of environmental concern were similar in all four towns, but receptivity to various planning activities was consistently greater among residents of the Tug Hill Region. Paired comparisons of the four towns demonstrated no differences between towns of the same region and significant differences between towns of different regions. Public support for regional planning is greater in the Tug Hill Region than in the Adirondack Park.  相似文献   

6.
Agricultural landscapes illustrate the impact of human actions on physical settings, and differential human pressures cause these landscapes to change with time. Our study explored changes in the terraced landscapes of Nisyros Island, Greece, focusing on the socioeconomic aspects during two time periods using field data, cadastral research, local documents, and published literature, as well as surveys of the islanders. Population increases during the late 19th to early 20th centuries marked a significant escalation of terrace and dry stone wall construction, which facilitated cultivation on 58.4% of the island. By the mid-20th century, the economic collapse of agricultural activities and consequent emigration caused the abandonment of cultivated land and traditional management practices, dramatically reducing farm and field numbers. Terrace abandonment continued in recent decades, with increased livestock grazing becoming the main land management tool; as a result, both farm and pasture sizes increased. Neglect and changing land use has led to deterioration and destruction of many terraces on the island. We discuss the socioeconomic and political backgrounds responsible for the land-use change before World War II (annexation of Nisyros Island by the Ottoman Empire, Italy, and Greece; overseas migration opportunities; and world transportation changes) and after the war (social changes in peasant societies; worldwide changes in agricultural production practices). The adverse landscape changes documented for Nisyros Island appear to be inevitable for modern Mediterranean rural societies, including those on other islands in this region. The island’s unique terraced landscapes may qualify Nisyros to become an archive or repository of old agricultural management techniques to be used by future generations and a living resource for sustainable management.  相似文献   

7.
Calculations of the annual input of heavy metals to Jamaica Bay, New York, USA, reveal that sewage effluent carries the largest quantities of Ni, Zn, Cu, and Cd to the bay. Storm sewers and atmospheric fallout are the main sources of Pb. Atmospheric fallout of Zn, Cu, and Cd, although smaller than the combined input from sewers, contributes a significant fraction of these metals. The metal input from landfill leachate is far smaller than that from other sources. Analysis of available data shows that metal concentrations in the sediment of the bay correlate with each other and with percent total organic carbon (%TOC). This is consistent with the observation that the input of metals is predominantly associated with sewage. It is demonstrated that metal-TOC ratios, rather than metal concentrations, must be used in efforts to detect local intensive sources of metals in solution; metal-TOC ratios in intertidal sediment adjacent to these landfills are elevated by the adsorption of leachate metals, while metal concentrations are not. Subtidal sediment within a few hundred meters from two landfills shows no evidence of the addition of metals from that source, which is consistent with the small input of metals estimated for these landfills. The evidence cited in this study sharply contradicts the implication made in a widely publicized report issued by an environmental advocacy group that a significant link exists between metals found in subtidal sediment of Jamaica Bay and landfill leachate.  相似文献   

8.
Satellite imagery is a useful tool for large-scale habitat analysis; however, its limitations need to be tested. We tested these limitations by varying the methods of a habitat evaluation for white-tailed deer (Odocoileus virginianus) in the Adirondack Park, New York, USA, utilizing harvest data to create and validate the assessment models. We used two classified images, one with a large minimum mapping unit but high accuracy and one with no minimum mapping unit but slightly lower accuracy, to test the sensitivity of the evaluation to these differences. We tested the utility of two methods of assessment, habitat suitability index modeling, and pattern recognition modeling. We varied the scale at which the models were applied by using five separate sizes of analysis windows. Results showed that the presence of a large minimum mapping unit eliminates important details of the habitat. Window size is relatively unimportant if the data are averaged to a large resolution (i.e., township), but if the data are used at the smaller resolution, then the window size is an important consideration. In the Adirondacks, the proportion of hardwood and softwood in an area is most important to the spatial dynamics of deer populations. The low occurrence of open area in all parts of the park either limits the effect of this cover type on the population or limits our ability to detect the effect. The arrangement and interspersion of cover types were not significant to deer populations.  相似文献   

9.
Ecological analysis of the seasonal distribution of marine phytobenthos and zoobenthos has been studied for Nisyros Island, south-east Greece. A total number of 114 species of phytobenthos, 78 soft-substrate zoobenthos species and 56 hard-substrate zoobenthos species were identified during the study. Analysis of seasonal distribution of phytobenthos showed that there exists an almost stable community structure both in terms of number of species per group and coverage as a result of the stable thermal conditions occurring in the area. Chlorophyceae show the lowest number of species and coverage while Rhodophyceae the highest. Hard-substrate zoobenthos showed a typical distribution found in other areas of Greece with crustaceans the dominant species. The community structure does not show seasonal variations as it is closely associated with phytobenthos species. On the other hand, the soft-substrate zoobenthos community shows differences from the typical Greek profile with Polychaeta the dominant taxon. Qualitative study showed that the dominant species are carnivorous worms while sediment- or filter-feeders appear in low numbers indicating low organic content of the sediment and low levels of organic pollution. The same pattern was also described for Milos Island (a volcanic island in the Central Aegean Sea) and seems to be a generalized concept for volcanic islands.  相似文献   

10.
a (Chl a), silica (Si), and chloride (Cl) through the use of proper statistical techniques. Results indicate no statistically significant changes in the concentrations of TP, Chl a, or Si in the spring or summer from 1981 to 1993. A significant temporal trend of increase in Cl concentration is, however, detected. This is perhaps the strongest evidence that the development of the Lake George watershed has affected lakewater chemistry. In spring, the concentrations of TP, Chl a, Si, and Cl, averaged over all 13 years, were higher in the south basin, but differences are not statistically significant (i.e., P > 0.05). In summer, Si was slightly but significantly lower, and Cl was nonsignificantly higher in the south basin. Significant interactions between temporal and spatial changes are detected based only on summer values of TP and Chl a, indicating differential trends of change for these two variables in the south and north basins during the last 13 years.  相似文献   

11.
Levels of polychlorinated biphenyls (PCBs) have been determined in the water, in the soils and sediments, and in the biota of a small upstate New York public water supply system, which is near the heavily polluted section of the Hudson River and a disposal site for PCB-containing waste. The impounded water exhibits a significant and relatively uniform level of Aroclor 1016, whereas the ground and surface waters supplying the reservoir do not. Rainfall, which exhibits a high level of Aroclor 1016, constitutes a small but significant source of PCB input. Soil and sediment samples exhibit significant median levels of both Aroclor 1016 and Aroclor 1254, but the local concentrations vary widely. The biota exhibit much higher PCB levels than the water or sediments, and show a strong preference for Aroclor 1254. The PCB levels in the macroinvertebrates are particularly high, suggesting that these organisms may provide a useful indicator for monitoring PCB contamination in aquatic systems. Risk assessment indicates that the lifetime incremental risk of cancer associated with the drinking water is below 10–6. Management of such low levels of PCB contamination is best achieved by reducing the input of PCBs.  相似文献   

12.
/ Tidal marshes have been actively restored in Connecticut for nearly 20 years, but evaluations of these projects are typically based solely on observations of vegetation change. A formerly impounded valley marsh at the Barn Island Wildlife Management Area is a notable exception; previous research at this site has also included assessments of primary productivity, macroinvertebrates, and use by fishes. To determine the effects of marsh restoration on higher trophic levels, we monitored bird use at five sites within the Barn Island complex, including both restoration and reference marshes. Use by summer bird populations within fixed plots was monitored over two years at all sites. Our principal focus was Impoundment One, a previously impounded valley marsh reopened to full tidal exchange in 1982. This restoration site supported a greater abundance of wetland birds than our other sites, indicating that it is at least equivalent to reference marshes within the same system for this ecological function. Moreover, the species richness of birds and their frequency of occurrence at Impoundment One was greater than at 11 other estuarine marshes in southeastern Connecticut surveyed in a related investigation. A second marsh, under restoration for approximately ten years, appears to be developing in a similar fashion. These results complement previous studies on vegetation, macroinvertebrates, and fish use in this system to show that, over time, the reintroduction of tidal flooding can effectively restore important ecological functions to previously impounded tidal marshes.KEY WORDS: Estuarine; Tidal marsh; Wetland birds; Restoration  相似文献   

13.
Communication of knowledge between the scientific and management communities is a difficult process complicated by the distinctive nature of professional career goals of scientists and decision-makers. This article provides a case history highlighting a collaboration between the science and management communities that resulted from a response to a 2004 hypoxia, or low dissolved oxygen, event in Long Bay, off Myrtle Beach, South Carolina. A working group of scientists and decision-makers was established at the time of the event and has continued to interact to develop a firm understanding of the drivers responsible for hypoxia formation in Long Bay. Several factors were found to be important to ensure that these collaborative efforts were productive: (1) genuine interest in collaboratively working across disciplines to examine a problem; (2) commitment by agency leadership, decision-makers, and researchers to create successful communication mechanisms; (3) respect for each others’ perspectives and an understanding how science and management are performed and that they are not mutually exclusive; (4) networking among researchers and decision-makers to ensure appropriate team members are involved in the process; (5) use of decision-maker input in the formulation of research and monitoring projects; and (6) commitment of resources for facilitation to ensure that researchers and decision-makers are communicating effectively.  相似文献   

14.
The aquifer and groundwater regime has been affected by the earthquake and tsunami of December 26, 2004, particularly on the islands and coastal regions of India. The groundwater regime on many islands of Andaman and Nicobar islands, which is the only source of fresh water on the islands, has been found to be deteriorated. Detailed hydrogeological studies have been carried out at one of the tiny islands of Andaman, namely Neill Island, and results have been compared with prior observations. It has been found that the shell limestone aquifer at a few places has developed cracks due to the earthquake and these openings have allowed quick movement of seawater into the aquifer resulting into deterioration of groundwater quality. In the places where the aquifer is at sea level, the tsunami waves have caused seawater ingress. Most parts of the island which have hard mudstone as a base and where the aquifer lies much above sea level, did not show any change in groundwater regime.  相似文献   

15.
In 1979, the Pinelands Commission was established as a regional land-use planning and regulatory agency charged with the implementation of a Comprehensive Management Plan (CMP) for the Pinelands National Reserve (New Jersey, USA). The CMP was created to balance land preservation and development interests in the Reserve. Because water-quality degradation from developed and agricultural landscapes is associated with changes in the composition of biological communities, monitoring landscape changes provides one of the most direct measures of the impact of land-use policies on the Pinelands ecosystem. In this study, we prepared detailed, land-cover maps within randomly selected aerial-photograph plots for a major watershed in the Reserve. We used these land-cover maps to quantify changes in landscape composition and structure (i.e., patch size, patch area, and number of patches) and characterize land-cover transitions in the basin between 1979 and 1991. Because the study period represented the first 12 years of the regional-planning effort in the Reserve, we evaluated the relationship between land-cover transitions and Commission management-area designations which permit different land-use intensities. Although the landscape composition was similar in 1979 and 1991, we found an increase in the total area and number of developed-land, managed-grassland, and barren-land patches. An increase in the number of patches and a decrease in the total area and median and third-quartile patch sizes for forest land and for all patches regardless of cover type indicated that fragmentation of forest land and the landscape as a whole occurred during the study period. The major land-cover transitions that occurred during the period were the loss of forest land to development and associated cover types and the conversion of one agricultural type to another. Overall, land-cover transitions during the period were found to be consistent with the Commission management-area designations, which indicated that the regional-planning effort has been successful in directing human activities to appropriate areas of the basin.  相似文献   

16.
The streams tributary to acidic Cone Pond, pH 4.5–4.8, and circumneutral Black Pond, pH 5.3–6.4, in the White Mountains of New Hampshire, USA, were monitored for a year. The watersheds of these two ponds were characterized in terms of geology and stream hydrology. Chemical gradients and patterns in rock weathering and groundwater discharge explain many of the differences in mineral content and acidity of the streams. The rocks of Black watershed produced an average of ten times the equivalent of basic cations as rocks from Cone watershed. This is on the same order as the difference in acidity of the two streams. Down-stream changes in stream chemistry follow differing patterns, but reflect the same principle of residence time and water path length controlling chemical evolution of streamwater. Watershed and aquatic managers may use these parameters in an inexpensive and simple assessment of the susceptibility of individual streams and ponds to acidification. A method is recommended to determine quickly the potential influence of bedrock type to aquatic chemistry.  相似文献   

17.
The scenic effects of clearcutting have been a volatile issue for the American public for much of the past century. A better understanding of the scenic perceptions associated with the cumulative visible effects of clearcutting should contribute to better decisions about its use. This study evaluates the scenic impacts of simulated alternative clearcutting management systems for the White Mountain National Forest. Alternatives represented an unharvested view, and views with removal of 1–5% of the timber every 12 years using either scattered or concentrated clearcut units of 5, 15 and 30 acres in two viewsheds. A random sample of local citizens, four groups of opinion leaders, and US Forest Service employees evaluated these alternatives. Each factor accounts for significant differences in scenic value. All groups rated the scenic value of unharvested scenes very high. All groups find a large drop in scenic value with the introduction of even the least intense harvesting activity. All groups indicated a statistically significant decrease in visual quality as the intensity of harvesting increases. This effect continues throughout the range of harvesting intensities until the level of sustainable yield is reached. In addition, patches 12–15 acres in size were preferred to larger and smaller ones.  相似文献   

18.
Morley, Terry R., Andrew S. Reeve, and Aram J.K. Calhoun, 2011. The Role of Headwater Wetlands in Altering Streamflow and Chemistry in a Maine, USA Catchment. Journal of the American Water Resources Association (JAWRA) 1‐13. DOI: 10.1111/j.1752‐1688.2011.00519.x Abstract: Headwater wetlands, including hillside seeps, may contribute to downstream systems disproportionately to their relatively small size. We quantified the hydrology and chemistry of headwater wetlands in a central Maine, USA, catchment from 2003 to 2005 to determine their role in maintaining headwater streamflow and in affecting stream chemistry. A few of these headwater wetlands, commonly referred to as “seeps,” were characterized by relatively high groundwater discharge. During summer base flow, seeps were the primary source of surface water to the stream, contributing between 40 and 80% of stream water. Comparisons of groundwater and surface water dominant ion chemistry revealed only slight differences at the bedrock interface; however, significant changes occurred at the shallow groundwater‐surface water interface where we found decreases in total and individual cation concentrations with decreasing depth. Seep outflows significantly increased total cation and calcium concentrations in streams. Outflows at two seeps produced relatively high nitrate concentrations (88 ± 15 and 93 ± 15 μg/l respectively), yet did not correspond to higher nitrate in stream water below seep outflows (2 ± 1 μg/l). We demonstrate that small wetlands (< 1,335 m2) can contribute to headwater stream processes by linking groundwater and surface‐water systems, increasing the duration and magnitude of stream discharge, and by affecting stream chemistry, particularly during periods of base flow.  相似文献   

19.
/ We used linear regression to independently and jointly relate specific conductance and pH measured at New Jersey Pinelands stream sites to the percentage of altered land in a watershed. Percentage altered land included developed and agricultural land uses and represented watershed disturbance for a given site. Median values calculated for a 2-year period (September 1992 through August 1994) characterized pH and specific conductance at the study sites. We found the relationships between the median values for both water-quality measures and percentage altered land for a site to be consistent across subregion and dominant altered-land use. Our results also demonstrated that the water-quality/altered-land relationships developed using median values were similar to relationships developed using data from any single-sample period within the entire study period. Individually, pH and specific conductance explained 48% and 56%, respectively, of the variability in watershed disturbance among study sites. The joint use of pH and specific conductance explained 79% of the watershed disturbance variability among sites. The joint use of these easily obtained water-quality measures can provide a quick assessment of instream water-quality impacts from upstream watershed disturbance at any Pinelands stream site. Additionally, a range in pH and specific conductance, and hence a range in ambient water quality, can be predicted for a given altered-land percentage or a change in existing altered-land conditions.  相似文献   

20.
This study utilizes remote sensing derived forest aboveground biomass (AGB) estimates and ownership information obtained from the Protected Areas Database (PAD), combining landscape analyses and GIS techniques to demonstrate how different ownerships (public, regulated private, and other private) relate to the spatial distribution of AGB in New England states of the USA. “Regulated private” lands were dominated by lands in Maine covered by a Land Use Regulatory Commission. The AGB means between all pairs of the identified ownership categories were significantly different (P < 0.05). Mean AGB observed in public lands (156 Mg/ha) was 43% higher than that in regulated private lands (109 Mg/ha), or 30% higher than that of private lands as a whole. Seventy-seven percent of the regional forests (or about 9,300 km2) with AGB >200 Mg/ha were located outside the area designated in the PAD and concentrated in western MA, southern VT, southwestern NH, and northwestern CT. While relatively unfragmented and high-AGB forests (>200 Mg/ha) accounted for about 8% of total forested land, they were unevenly proportioned among the three major ownership groups across the region: 19.6% of the public land, 0.8% of the regulated private land, and 11.0% of the other private land. Mean disturbance rates (in absolute value) between 1992 and 2001 were 16, 66, and 19 percent, respectively, on public, regulated private, and other private land. This indicates that management practices from different ownerships have a strong impact on dynamic changes of landscape structures and AGB distributions. Our results may provide insight information for policy makers on issues regarding forest carbon management, conservation biology, and biodiversity studies at regional level.  相似文献   

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