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121.
David W. York Benjamin C. Dysart Lawrence W. Gahan 《Journal of the American Water Resources Association》1977,13(2):283-298
ABSTRACT: The previous paper in this two-part series presented the basic information of a newly developed mathematical model of multiple-use in natural areas. The model is a unified system for the assessment of cases where development is proposed for relatively natural areas. This paper presents the results of an application of the model to a study of the proposed timber harvest in the Great Santec Swamp in South Carolina. This was done in an effort to demonstrate the utility of the model as a planning and assessment tool. Four potential uses of the Swamp were investigated: logging of hardwood saw timber, hunting, fishing, and nature observation. The model system proved to be extremely useful in the evaluation of potential management schemes and in the selection of the most promising or optimal management plan. 相似文献
122.
123.
The jurisdictional framework for municipal action to reduce greenhouse gas emissions: Case studies from Canada, the USA and Germany 总被引:1,自引:0,他引:1
This paper addresses two questions: (1) Given a commitment at the national level to reduce greenhouse gas (GHG) emissions, what tools are available to national-level governments to induce complimentary actions required at subnational levels? (2) In the absence of a serious commitment at national and regional levels to reduce GHG emissions, what is the scope for, and jurisdictional rights of, cities to undertake actions? In this context, federal, regional and municipal legislation relevant for GHG emissions is examined in Canada, the USA and Germany. Regarding the first question, different national governments find themselves in considerably different positions to implement climate initiatives at subnational levels, with the German government in the strongest position and the Canadian government in the weakest. The implications of this for a nation's willingness to adopt emission reduction targets could be serious. Regarding the second question, there are few significant differences among Canadian, US and German municipalities' jurisdictional capabilities (and limitations) to reduce GHG emissions. Though limited in their legal capacity, these municipalities demonstrate that through their own, often informal, initiatives they can reinforce and compliment the more formal, regulatory actions by senior-level governments, thereby paving the way for senior-level governments to deliver meaningful domestic emission reductions. 相似文献
124.
Benjamin M. Simon 《Journal of the American Water Resources Association》2002,38(5):1187-1194
ABSTRACT: Recent years have seen an accelerating trend toward devolution and privatization of water supply and distribution infrastructure. This paper discusses and analyzes the experience to date of the federal Bureau of Reclamation's efforts to title transfer to non federal entities. The paper also discusses the concepts of federalism and devolution in the context of Reclamation's title transfer activities. 相似文献
125.
Grahame Applegate Blair Freeman Benjamin Tular Latifa Sitadevi Timothy C. Jessup 《Ambio》2022,51(4):863
Indonesia is home to around 45% of the world’s tropical peatlands which continue to be degraded on a large scale by deforestation, drainage and fire, contributing massively to global GHG emissions. Approaches to restoring the peat–water balance and reducing emissions in peat hydrological units, through managing them based either on full protection or large-scale commercial production, have generally failed to address environmental and local community needs. We present published and unpublished findings pointing to the need for an integrated peatland protection and restoration strategy based first on raising water levels in degraded (drained) peatlands and maintaining them in forested peatlands, thus, reducing GHG emissions. Second, the strategy incorporates ecologically sound agroforestry business models that strengthen livelihoods of smallholders and so sustain their interest in sustainably managing the peatlands. In this paper, we focus on the second element of this strategy in Indonesia. Eight agroforestry business models are proposed based on their merits to attract both smallholders and commercial investors as well as their compatibility with hydrological rehabilitation of the peatlands. While financial returns on investment will vary across sites and countries, our analysis indicates that some models can be profitable over both short and longer time periods with relatively low levels of investment risk. 相似文献
126.
Benjamin A. Lyons Ariel Hasell Natalie Jomini Stroud 《Environmental Communication: A Journal of Nature and Culture》2018,12(7):876-894
Some extreme weather events may be more likely to affect climate change beliefs than others, in part because schema individuals possess for different events could vary in encouraging such links. Using a representative sample of U.S. adults and geocoded National Weather Service data, we examine how a range of extreme weather event categories relate to climate change beliefs, and the degree to which individuals’ self-reported experiences are shaped by their political views across event types. For tornado, hurricane, and flood events, we find no link with beliefs. For polar vortex and drought events, we find that although self-reported experience is linked with climate beliefs, reporting of these experiences is influenced by political identity and partisan news exposure. These findings underscore a limited role for extreme weather experiences in climate beliefs, and show that events more open to interpretation, such as droughts and polar vortex disturbances, are most likely to be seen through a partisan lens. 相似文献
127.
Evaluation of Progress in Achieving TMDL Mandated Nitrogen Reductions in the Neuse River Basin, North Carolina 总被引:2,自引:0,他引:2
Management efforts to control excess algal growth in the Neuse River and Estuary, North Carolina began in the 1980s, with
an initial focus on phosphorus (P) input reduction. However, continued water quality problems in the 1990s led to development
of a Total Maximum Daily Load (TMDL) for nitrogen (N) in 1999 to improve conditions in N-sensitive estuarine waters. Evaluation
of the effectiveness of management actions implemented in the Neuse River basin is a challenging endeavor due to natural variations
in N export associated with climate. A simplified approach is presented that allows evaluation of trends in flow-normalized
nutrient loading to provide feedback on effectiveness of implemented actions to reduce N loading to estuarine waters. The
approach is applied to five watershed locations, including the headwaters of the Neuse Estuary. Decreases in nitrate + nitrite
(NO3–N) concentrations occurred throughout the basin and were largest just downstream of the Raleigh metropolitan area. Conversely,
concentrations of total Kjeldahl N (TKN) increased at many stations, particularly under high flow conditions. This indicates
a relative increase in organic N (Org-N) inputs since the mid-1990s. Overall, patterns in different N fractions at watershed
stations indicate both partial success in reducing N inputs and ongoing challenges for N loading under high flow conditions.
In downstream waters, NO3–N concentrations decreased concurrent with TMDL implementation in the upper portion of the estuary but not in the middle
and lower reaches. The lack of progress in the middle and lower reaches of the estuary may, at least in part, be affected
by remineralization of settled particle-bound N deposited under high river flows. 相似文献
128.
Modeling the Spatially Varying Water Balance Processes in a Semiarid Mountainous Watershed of Idaho1
Benjamin T. Stratton Venakataramana Sridhar Molly M. Gribb James P. McNamara Balaji Narasimhan 《Journal of the American Water Resources Association》2009,45(6):1390-1408
Stratton, Benjamin T., Venakataramana Sridhar, Molly M. Gribb, James P. McNamara, and Balaji Narasimhan, 2009. Modeling the Spatially Varying Water Balance Processes in a Semiarid Mountainous Watershed of Idaho. Journal of the American Water Resources Association (JAWRA) 45(6):1390‐1408. Abstract: The distributed Soil Water Assessment Tool (SWAT) hydrologic model was applied to a research watershed, the Dry Creek Experimental Watershed, near Boise Idaho to investigate its water balance components both temporally and spatially. Calibrating and validating SWAT is necessary to enable our understanding of the water balance components in this semiarid watershed. Daily streamflow data from four streamflow gages were used for calibration and validation of the model. Monthly estimates of streamflow during the calibration phase by SWAT produced satisfactory results with a Nash Sutcliffe coefficient of model efficiency 0.79. Since it is a continuous simulation model, as opposed to an event‐based model, it demonstrated the limited ability in capturing both streamflow and soil moisture for selected rain‐on‐snow (ROS) events during the validation period between 2005 and 2007. Especially, soil moisture was generally underestimated compared with observations from two monitoring pits. However, our implementation of SWAT showed that seasonal and annual water balance partitioning of precipitation into evapotranspiration, streamflow, soil moisture, and drainage was not only possible but closely followed the trends of a typical semiarid watershed in the intermountain west. This study highlights the necessity for better techniques to precisely identify and drive the model with commonly observed climatic inversion‐related snowmelt or ROS weather events. Estimation of key parameters pertaining to soil (e.g., available water content and saturated hydraulic conductivity), snow (e.g., lapse rates, melting), and vegetation (e.g., leaf area index and maximum canopy index) using additional field observations in the watershed is critical for better prediction. 相似文献
129.
Benjamin Okang’ Odumo Gregoria Carbonell Hudson Kalambuka Angeyo Jayanti Purshottam Patel Manuel Torrijos José Antonio Rodríguez Martín 《Environmental science and pollution research international》2014,21(21):12426-12435
This work considered the environmental impact of artisanal mining gold activity in the Migori–Transmara area (Kenya). From artisanal gold mining, mercury is released to the environment, thus contributing to degradation of soil and water bodies. High mercury contents have been quantified in soil (140 μg kg?1), sediment (430 μg kg?1) and tailings (8,900 μg kg?1), as expected. The results reveal that the mechanism for transporting mercury to the terrestrial ecosystem is associated with wet and dry depositions. Lichens and mosses, used as bioindicators of pollution, are related to the proximity to mining areas. The further the distance from mining areas, the lower the mercury levels. This study also provides risk maps to evaluate potential negative repercussions. We conclude that the Migori–Transmara region can be considered a strongly polluted area with high mercury contents. The technology used to extract gold throughout amalgamation processes causes a high degree of mercury pollution around this gold mining area. Thus, alternative gold extraction methods should be considered to reduce mercury levels that can be released to the environment. 相似文献
130.
Pharmaceuticals and personal care products found in the Great Lakes above concentrations of environmental concern 总被引:2,自引:0,他引:2
The monitoring of pharmaceuticals and personal care products (PPCPs) has focused on the distribution in rivers and small lakes, but data regarding their occurrence and effects in large lake systems, such as the Great Lakes, are sparse. Wastewater treatment processes have not been optimized to remove influent PPCPs and are a major source of PPCPs in the environment. Furthermore, PPCPs are not currently regulated in wastewater effluent. In this experiment we evaluated the concentration, and corresponding risk, of PPCPs from a wastewater effluent source at varying distances in Lake Michigan. Fifty-four PPCPs and hormones were assessed on six different dates over a two-year period from surface water and sediment samples up to 3.2 km from a wastewater treatment plant and at two sites within a harbor. Thirty-two PPCPs were detected in Lake Michigan and 30 were detected in the sediment, with numerous PPCPs being detected up to 3.2 km away from the shoreline. The most frequently detected PPCPs in Lake Michigan were metformin, caffeine, sulfamethoxazole, and triclosan. To determine the ecological risk, the maximum measured environmental concentrations were compared to the predicted no-effect concentration and 14 PPCPs were found to be of medium or high ecological risk. The environmental risk of PPCPs in large lake systems, such as the Great Lakes, has been questioned due to high dilution; however, the concentrations found in this study, and their corresponding risk quotient, indicate a significant threat by PPCPs to the health of the Great Lakes, particularly near shore organisms. 相似文献