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31.
It is commonly put forward that effective uptake of research in policy or practice must be built upon a foundation of active knowledge exchange and stakeholder engagement during the research. However, what is often lacking is a systematic appreciation of the specific practices of knowledge exchange and their relative merits. The paper reports on a 2009 survey of 21 research projects within the UK Research Councils' Rural Economy and Land Use Programme regarding the involvement and perceived impact of over a thousand stakeholders in the research. The survey reveals that most stakeholders were involved as research subjects or as event participants. Large numbers were also engaged in the research process itself, including involvement in shaping the direction of research. Stakeholder engagement is perceived as bringing significant benefits to the process of knowledge production. A close relationship is found between mechanisms and approaches to knowledge exchange and the spread of benefits for researchers and stakeholders. Mutual benefits are gained from exchange of staff or where stakeholders are members of research advisory groups. Different stakeholder sectors are also associated with different patterns of engagement, which lead to contrasting impact patterns. Any efforts to alter knowledge exchange processes and outcomes must overcome these differing engagement tendencies. Overall, much greater attention should be given to early processes of knowledge exchange and stakeholder engagement within the lifetime of research projects. 相似文献
32.
Charles D. Ikenberry William G. Crumpton Jeffrey G. Arnold Michelle L. Soupir Philip W. Gassman 《Journal of the American Water Resources Association》2017,53(6):1267-1280
The ability to accurately simulate flow and nutrient removal in treatment wetlands within an agricultural, watershed‐scale model is needed to develop effective plans for meeting nutrient reduction goals associated with protection of drinking water supplies and reduction of the Gulf of Mexico hypoxic zone. The objectives of this study were to incorporate new equations for wetland hydrology and nutrient removal in Soil and Water Assessment Tool (SWAT), compare model performance using original and improved equations, and evaluate the ramifications of errors in watershed and tile drain simulation on prediction of NO3‐N dynamics in wetlands. The modified equations produced Nash‐Sutcliffe Efficiency values of 0.88 to 0.99 for daily NO3‐N load predictions, and percent bias values generally less than 6%. However, statistical improvement over the original equations was marginal and both old and new equations provided accurate simulations. The new equations reduce the model's dependence on detailed monitoring data and hydrologic calibration. Additionally, the modified equations increase SWAT's versatility by incorporating a weir equation and an irreducible nutrient concentration and temperature coefficient. Model improvements enhance the utility of SWAT for simulating flow and nutrients in wetlands and other impoundments, although performance is limited by the accuracy of inflow and NO3‐N predictions from the contributing watershed. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series. 相似文献
33.
34.
Acid sulfate soils have been described as the “nastiest soils on earth” because of their strong acidity, increased mobility of potentially toxic elements and limited bioavailability of nutrients. They only cover a small area of the world's total problem soils, but often have significant adverse effects on agriculture, aquaculture and the environment on a local scale. Their location often coincides with high population density areas along the coasts of many developing countries. As a result, their negative impacts on ecosystems can have serious implications to those least equipped for coping with the low crop yields and reduced water quality that can result from acid sulfate soil disturbance. The Millennium Ecosystem Assessment called on by the United Nations in 2000 emphasised the importance of ecosystems for human health and well-being. These include the service they provide as sources of food and water, through the control of pollution and disease, as well as for the cultural services ecosystems provide. While the problems related to agriculture, aquaculture and the environment have been the focus of many acid sulfate soil management efforts, the connection to human health has largely been ignored. This paper presents the potential health issues of acid sulfate soils, in relation to the ecosystem services identified in the Millennium Ecosystem Assessment. It is recognised that significant implications on food security and livelihood can result, as well as on community cohesiveness and the spread of vector-borne disease. However, the connection between these outcomes and acid sulfate soils is often not obvious and it is therefore argued that the impact of such soils on human well-being needs to be recognised in order to raise awareness among the public and decision makers, to in turn facilitate proper management and avoid potential human ill-health. 相似文献
35.
Luisa T. Molina Mario J. Molina Robert S. Slott Charles E. Kolb Philip K. Gbor Fan Meng 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1-73
Abstract About half of the world's population now lives in urban areas because of the opportunity for a better quality of life. Many of these urban centers are expanding rapidly, leading to the growth of megacities, which are often defined as metropolitan areas with populations exceeding 10 million inhabitants. These concentrations of people and activity are exerting increasing stress on the natural environment, with impacts at urban, regional and global levels. In recent decades, air pollution has become one of the most important problems of megacities. Initially, the main air pollutants of concern were sulfur compounds, which were generated mostly by burning coal. Today, photochemical smog—induced primarily from traffic, but also from industrial activities, power generation, and solvents—has become the main source of concern for air quality, while sulfur is still a major problem in many cities of the developing world. Air pollution has serious impacts on public health, causes urban and regional haze, and has the potential to contribute significantly to global climate change. Yet, with appropriate planning megacities can efficiently address their air quality problems through measures such as application of new emission control technologies and development of mass transit systems. This review is focused on nine urban centers, chosen as case studies to assess air quality from distinct perspectives: from cities in the industrialized nations to cities in the developing world. This review considers not only megacities, but also urban centers with somewhat smaller populations, for while each city—its problems, resources, and outlook—is unique, the need for a holistic approach to complex environmental problems is the same. There is no single strategy to reduce air pollution in megacities; a mix of policy measures will be needed to improve air quality. Experience shows that strong political will coupled with public dialogue is essential to effectively implement the regulations required to address air quality. 相似文献
36.
Diffuse pollution remains a major threat to surface waters due to eutrophication caused by phosphorus (P) transfer from agricultural land. Vegetated buffer strips (VBSs) are increasingly used to mitigate diffuse P losses from agricultural land, having been shown to reduce particulate P transfer. However, retention of dissolved P (DP) has been lower, and in some cases VBSs have increased delivery to surface waters. The aims of this review were (i) to develop a conceptual model to enhance the understanding of VBS functioning in terms of DP, (ii) to identify key processes within the model that affect DP retention and delivery, and (iii) to explore evidence for the controls on these processes. A greater understanding in these areas will allow the development of management strategies that enhance DP retention. We found evidence of a surface layer in buffer strip soils that is enriched in soluble P compared with adjacent agricultural land and may be responsible for the reported increased DP delivery. Through increased biological activity in VBSs, plants and microorganisms may assimilate P from particulates retained in the VBSs or native soil P and remobilize this P in a more soluble form. These conclusions are based on a limited amount of research, and a better understanding of biogeochemical cycling of P in buffer strip soils is required. 相似文献
37.
Seshasayi Dharmavaram Philip K. Hopke 《Journal of the Air & Waste Management Association (1995)》2013,63(6):812-813
Abstract This study comprehensively characterizes hourly fine particulate matter (PM2.5) concentrations measured via a tapered element oscillating microbalance (TEOM), β-gauge, and nephelometer from four different monitoring sites in U.S. Environment Protection Agency (EPA) Region 5 (in U.S. states Illinois, Michigan, and Wisconsin) and compares them to the Federal Reference Method (FRM). Hourly characterization uses time series and autocorrelation. Hourly data are compared with FRM by averaging across 24-hr sampling periods and modeling against respective daily FRM concentrations. Modeling uses traditional two-variable linear least-squares regression as well as innovative nonlinear regression involving additional meteorological variables such as temperature and humidity. The TEOM shows a relationship with season and temperature, linear correlation as low as 0.7924 and nonlinear model correlation as high as 0.9370 when modeled with temperature. The β-gauge shows no relationship with season or meteorological variables. It exhibits a linear correlation as low as 0.8505 with the FRM and a nonlinear model correlation as high as 0.9339 when modeled with humidity. The nephelometer shows no relationship with season or temperature but a strong relationship with humidity is observed. A linear correlation as low as 0.3050 and a nonlinear model correlation as high as 0.9508 is observed when modeled with humidity. Nonlinear models have higher correlation than linear models applied to the same dataset. This correlation difference is not always substantial, which may introduce a tradeoff between simplicity of model and degree of statistical association. This project shows that continuous monitor technology produces valid PM2.5 characterization, with at least partial accounting for variations in concentration from gravimetric reference monitors once appropriate nonlinear adjustments are applied. Although only one regression technically meets new EPA National Ambient Air Quality Standards (NAAQS) Federal Equivalent Method (FEM) correlation coefficient criteria, several others are extremely close, showing optimistic potential for use of this nonlinear adjustment model in garnering EPA NAAQS FEM approval for continuous PM2.5 sampling methods. 相似文献
38.
The In Salah Gas Joint Venture CO2 storage project has been in operation in Algeria since 2004 and is currently the world's largest onshore CO2 storage project. CO2 is injected into the saline aquifer of a gas reservoir several kilometres away from the gas producers. Current focus in the project is on implementing a comprehensive monitoring strategy and modelling the injection behaviour in order to ensure and verify safe long-term storage. A key part of this effort is the understanding of the processes involved in CO2 migration within relatively low-permeability sandstones and shales influenced by fractures and faults. We summarise our current understanding of the fault and fracture pattern at this site and show preliminary forecasts of the system performance using discrete fracture models and fluid flow simulations. Despite evidence of fractures at the reservoir/aquifer level, the thick mudstone caprock sequence is expected to provide an effective flow and mechanical seal for the storage system; however, quantification of the effects of fracture flow is essential to the site verification. 相似文献
39.
James W. Rivers Philip S. Gipson Donald P. Althoff Jeffrey S. Pontius 《Environmental management》2010,45(2):203-216
Military training activities are known to impact individual species, yet our understanding of how such activities influence
animal communities is limited. In this study, we used long-term data in a case study approach to examine the extent to which
the local small landbird community differed between a site in northeast Kansas that experienced intensive disturbance from
military training activities (Ft. Riley Military Installation) and a similar, nearby site that experienced minimal human disturbance
(Konza Prairie Biological Station). In addition, we characterized how the regional pool of potential colonizers influenced
local community dynamics using Breeding Bird Survey data. From 1991 to 2001, most species of small terrestrial landbirds (73%)
recorded during breeding surveys were found at both sites and the mean annual richness at Ft. Riley (39.0 ± 2.86 [SD]) was
very similar to that of Konza Prairie (39.4 ± 2.01). Richness was maintained at relatively constant levels despite compositional
changes because colonizations compensated local extinctions at both sites. These dynamics were driven primarily by woodland
species that exhibited stochastic losses and gains and were present at a low local and regional abundance. Our results suggest
that military training activities may mimic natural disturbances for some species in this area because the small landbird
community did not differ markedly between sites with and sites without extensive human disturbance. Although our results suggest
that military training is not associated with large changes in the avian community, additional studies are needed to determine
if this pattern is found in other ecological communities. 相似文献
40.
Michael J. White Daniel E. Storm Philip Busteed Scott Stoodley Shannon J. Phillips 《Environmental management》2010,45(5):1164-1174
In the United States, many state and federally funded conservation programs are required to quantify the water quality benefits
resulting from their efforts. The objective of this research was to evaluate the impact of conservation practices subsidized
by the Oklahoma Conservation Commission on phosphorus and sediment loads to Lake Wister. Conservation practices designed to
increase vegetative cover in grazed pastures were evaluated using Landsat imagery and the Soil and Water Assessment Tool (SWAT).
Several vegetative indices were derived from Landsat imagery captured before and after the implementation of conservation
practices. Collectively, these indicators provided an estimate of the change in vegetative soil cover attributable to conservation
practices in treated fields. Field characteristics, management, and changes in vegetative cover were used in the SWAT model
to simulate sediment and phosphorus losses before and after practice implementation. Overall, these conservation practices
yielded a 1.9% improvement in vegetative cover and a predicted sediment load reduction of 3.5%. Changes in phosphorus load
ranged from a 1.0% improvement to a 3.5% increase, depending upon initial vegetative conditions. The use of fertilizers containing
phosphorus as a conservation practice in low-productivity pastures was predicted by SWAT to increase net phosphorus losses
despite any improvement in vegetative cover. This combination of vegetative cover analysis and hydrologic simulation was a
useful tool for evaluating the effects of conservation practices at the basin scale and may provide guidance for the selection
of conservation measures subsidized in future conservation programs. 相似文献