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81.
Marie Claire Brisbois Rob C. de Loë 《Journal of Environmental Planning and Management》2017,60(5):883-900
Natural resource industries are increasingly significant actors in environmental decision-making. Possessing vast institutional and technical capacity, firms have an important role to play in ‘new’ governance strategies such as collaboration. These strategies are often based upon assumptions of equitable influence. This paper investigates the nature of resource industry participation in collaborative water governance in Canada, and the potential consequences of that participation as investigated using power theory. The study used comparative cases to reveal that resource industries are able to shape collaboration, and the issues collaborated upon, at multiple analytical levels both internal and external to the collaborative process in ways not available to other actors. Analysis also revealed that resource industry participation in collaboration did not reflect a commitment to engage in shared learning and the reexamination of values and interests as presupposed by collaborative theory. Collaboration is thus challenged in producing equitable, representative outcomes when resource industries participate. 相似文献
82.
83.
Lisa M. Fraley Andrew J. Miller Claire Welty 《Journal of the American Water Resources Association》2009,45(3):748-766
Abstract: A study was conducted between September 2003 and September 2006 to obtain baseline sediment inventories and monitor sediment transport and storage along a 3.7 km length of the channel of Valley Creek within Valley Forge National Historical Park, Pennsylvania. Valley Creek is a tributary of the Schuylkill River and drains an urbanizing 60.6 km2 watershed that currently has 18% impervious land cover. Numerous field methods were employed to measure the suspended sediment yield, longitudinal profile, cross‐sections, banklines, and particle size distribution of the streambed. Suspended sediment yield for the watershed was measured at a USGS gage located just upstream of the park boundary between July 2004 and July 2005, the period corresponding to field surveys of bank erosion and channel change. The estimated suspended sediment yield of 95.7 t/km2/year is representative of a year with unusually high discharge, including a storm event that produced a peak of 78 m3/s, the second highest discharge on record for the USGS gage. Based on the median annual streamflow for the 24 years of record at the USGS gage from 1983 to 2006, the median annual sediment yield is estimated to be closer to 34 t/km2/year, considerably lower than median and mean values for other sites within the region. The mass of silt, clay, and fine sand derived from bank erosion along the 3.7 km study reach during the field survey period accounts for an estimated 2,340 t, equivalent to about 43% of the suspended sediment load. The mass of fine sediment stored in the bed along the study reach was estimated at 1,500 t, with about 330 t of net erosion during the study period. Although bank erosion appears to be a potentially dominant source of sediment by comparison with annual suspended sediment load, bed sediment storage and potential for remobilization is of the same order of magnitude as the mass of sediment derived from bank erosion. 相似文献
84.
Biodiversity versus emergencies: the impact of restocking on Animal Genetic Resources after disaster
Heffernan C 《Disasters》2009,33(2):239-252
Restocking is a favoured option in supporting livelihoods after a disaster. With the depletion of local livestock populations, the introduction of new species and breeds will clearly affect biodiversity. Nevertheless, the impact of restocking on Animal Genetic Resources has been largely ignored. The aim of this paper, therefore, is to examine the consequences of restocking on biodiversity via a simple model. Utilising a hypothetical project based on cattle, the model demonstrates that more than one-third of the population was related to the original restocked animals after three generations. Under conditions of random breed selection, the figure declined to 20 per cent. The tool was then applied to a donor-led restocking project implemented in Bosnia-Herzegovina. By restocking primarily with Simmental cattle, the model demonstrated that the implementation of a single restocking project is likely to have accelerated the decline of the indigenous Buşa breed by a further nine per cent. Thus, greater awareness of the long-term implications of restocking on biodiversity is required. 相似文献
85.
Energy efficiency and conservation for individual Americans 总被引:1,自引:0,他引:1
D. Pimentel Jennifer Gardner Adam Bonnifield Ximena Garcia Julie Grufferman Claire Horan Julia Schlenker Emily Walling Emily Rochon 《Environment, Development and Sustainability》2009,11(3):523-546
Americans make up only 4% of the world population, yet currently consume 25% of the world’s fossil fuels. The U.S. imports
63% of its oil and it is predicted that by 2020 the U.S. will be importing 95% of its oil resources. Over the past century,
ample and affordable supplies of fossil fuels have powered the growth and prosperity of the economies of the US and other
countries. Within this century, world oil supplies will decline while demand is projected to continue to increase, suggesting
that we will have to transition to different fuels or become much more energy efficient or both. Looking ahead to the near
decades, estimates are that consumers will have to reduce their energy use by at least 50%. This reduction will be necessary
in large part due the decline in the availability of conventional oil and gas, but also because the U.S. population will continue
to grow in number. Although government action is important, individuals too often discount their ability to make significant
contributions to solving such major problems. This investigation identifies how informed and concerned individuals can collectively
conserve fossil energy.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.
An erratum to this article can be found at 相似文献
86.
Global Perspectives on Pollination Disruptions 总被引:2,自引:0,他引:2
87.
Texier S Prigent-Combaret C Gourdon MH Poirier MA Faivre P Dorioz JM Poulenard J Jocteur-Monrozier L Moënne-Loccoz Y Trevisan D 《Journal of environmental quality》2008,37(6):2299-2310
Our knowledge of Escherichia coli (E. coli) ecology in the field is very limited in the case of dairy alpine grassland soils. Here, our objective was to monitor field survival of E. coli in cow pats and underlying soils in four different alpine pasture units, and to determine whether the soil could constitute an environmental reservoir. E. coli was enumerated by MPN using a selective medium. E. coli survived well in cow pats (10(7) to 10(8) cells g(-1) dry pat), but cow pats disappeared within about 2 mo. In each pasture unit, constant levels of E. coli (10(3) to 10(4) cells g(-1) dry soil) were recovered from all topsoil (0-5 cm) samples regardless of the sampling date, that is, under the snow cover, immediately after snow melting, or during the pasture season (during and after the decomposition of pats). In deeper soil layers below the root zone (5-25 cm), E. coli persistence varied according to soil type, with higher numbers recovered in poorly-drained soils (10(3) to 10(4) cells g(-1) dry soil) than in well-drained soils (< 10(2) cells g(-1) dry soil). A preliminary analysis of 38 partial uidA sequences of E. coli from pat and soils highlighted a cluster containing sequences only found in this work. Overall, this study raises the possibility that fecal E. coli could have formed a naturalized (sub)population, which is now part of the indigenous soil community of alpine pasture grasslands, the soil thus representing an environmental reservoir of E. coli. 相似文献
88.
Morier I Guenat C Siegwolf R Védy JC Schleppi P 《Journal of environmental quality》2008,37(6):2012-2021
In temperate forest ecosystems, soil acts as a major sink for atmospheric N deposition. A (15)N labeling experiment in a hardwood forest on calcareous fluvisol was performed to study the processes involved. Low amounts of ammonium ((15)NH(4)(+)) or nitrate ((15)NO(3)(-)) were added to small plots. Soil samples were taken after periods ranging from 1 h to 1 yr. After 1 d, the litter layer retained approximately 28% of the (15)NH(4)(+) tracer and 19% of (15)NO(3)(-). The major fraction of deposited N went through the litter layer to reach the soil within the first hours following the tracer application. During the first day, a decrease in extractable (15)N in the soil was observed ((15)NH(4)(+): 50 to 5%; (15)NO(3)(-): 60 to 12%). During the same time, the amount of microbial (15)N remained almost constant and the (15)N immobilized in the soil (i.e., total (15)N recovered in the bulk soil minus extractable (15)N minus microbial (15)N) also decreased. Such results can therefore be understood as a net loss of (15)N from the soil. Such N loss is probably explained by NO(3)(-) leaching, which is enhanced by the well-developed soil structure. We presume that the N immobilization mainly occurs as an incorporation of deposited N into the soil organic matter. One year after the (15)N addition, recovery rates were similar and approximately three-quarters of the deposited N was recovered in the soil. We conclude that the processes relevant for the fate of atmospherically deposited N take place rapidly and that N recycling within the microbes-plants-soil organic matter (SOM) system prevents further losses in the long term. 相似文献
89.
Claire L. Schelske 《Journal of the American Water Resources Association》1989,25(6):1119-1130
ABSTRACT: Lake Okeechobee, the third largest lake in the United States, is a shallow, mixing basin with annual total phosphorus concentrations ranging from 50–100 μg P/L. Data, mainly from unpublished agency reports, are analyzed to determine if nutrients limit phytoplankton, to describe spatial and temporal variability in trophic state parameters, and to evaluate conclusions obtained from empirical trophic state models. Algal bioassay experiments that have been used to assess nutrient limitation have produced equivocal results. However, seasonal minima in orthophosphorus and inorganic nitrogen indicate that both nutrients may be limiting seasonally. Strong, but reverse north-south gradients and large seasonal changes in phosphorus and nitrogen concentrations, show that empirical models based on annual phosphorus loadings or concentrations are not adequate to predict chlorophyll concentrations or other trophic state variables. Spatially-segmented, multi-class phytoplankton-nutrient models of seasonal phytoplankton responses that are coupled with hydrodynamic models may provide predictability in assessing effects of changing nutrient loads on phytoplankton composition and standing crop. Successful modeling efforts of responses to nutrients also must deal with resuspended and benthic algae, periphyton, and emergent and submergent aquatic plants that must play important trophic roles in some of the lake basin. 相似文献
90.