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51.
Transitioning to renewable energy has become a global phenomenon. Attempts to explain development patterns are often fragmented, focusing on specific rationale for (un)successful deployment or the perspective of specific stakeholders. We recognize the importance for holistic insights for successful and effective environmental policy-making and planning in the context of renewable energy development. Using wind energy as an example, this paper provides methodological toolkits for utilizing content analysis (CA) to gain more holistic insights on renewable energy deployment and policy outcomes. Building on existing literature, past and ongoing research, three variations of CA are presented for understanding stakeholder conflicts surrounding wind energy development as well as public perceptions and responses to the technology across space and over time. Although newspapers are used as an example, these methodological protocols could be applied to diverse forms of data such as interviews, policy documents, reports, public meetings and letters of appeal.  相似文献   
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Rainfall simulation experiments were conducted on annual grassland and coastal sage scrub hillslopes to determine the quantities of C and N removed by surface runoff in sediment and solution. Undisturbed coastal sage scrub soils have very high infiltration capacities (> 140 mm h(-1)), preventing the generation of surface runoff. Trampling disturbance to the sage scrub plots dramatically reduced infiltration capacities, increasing the potential for surface runoff and associated nutrient loss. Infiltration capacities in the grassland plots (30-50 mm h(-1)) were lower than in the sage scrub plots. Loss rates of dissolved C and N in surface runoff from grasslands were 0.5 and 0.025 mg m(-2) s(-1) respectively, with organic N accounting for more than 50% of the dissolved N. Total dissolved losses with simulated rainfall were higher than losses in simulations with just surface runoff, demonstrating the importance of raindrop impact in transferring solutes into the flow. Experimental data were incorporated into a numerical model of runoff and sediment transport to estimate hillslope-scale sediment-bound nutrient losses from grasslands. According to the model results, sediment-bound nutrient losses are sensitive to the density of vegetation cover and rainfall intensity. The model estimates annual losses in surface runoff of 0.2 and 0.02 g m(-2) for sediment-hound C and N, respectively. The results of this study suggest that conversion of coastal sage scrub to annual grasslands increases hillslope nutrient losses and may affect stream water quality in the region.  相似文献   
53.
Biological assessment of aquatic ecosystems is widely employed as an alternative or complement to chemical and toxicity testing due to numerous advantages of using biota to determine ecosystem condition. These advantages, especially to developing countries, include the relatively low cost and technical requirements. This study was conducted to determine the biological impacts of aquaculture operations on effluent-receiving streams in the Ashanti Region of Ghana. We collected water, fish and benthic macroinvertebrate samples from 12 aquaculture effluent-receiving streams upstream and downstream of fish farms and 12 reference streams between May and August of 2009, and then calculated structural and functional metrics for biotic assemblages. Fish species with non-guarding mode of reproduction were more abundant in reference streams than downstream (P?=?0.0214) and upstream (P?=?0.0251), and sand-detritus spawning fish were less predominant in reference stream than upstream (P?=?0.0222) and marginally less in downstream locations (P?=?0.0539). A possible subsidy-stress response of macroinvertebrate family richness and abundance was also observed, with nutrient (nitrogen) augmentation from aquaculture and other farming activities likely. Generally, there were no, or only marginal differences among locations downstream and upstream of fish farms and in reference streams in terms of several other biotic metrics considered. Therefore, the scale of impact in the future will depend not only on the management of nutrient augmentation from pond effluents, but also on the consideration of nutrient discharges from other industries like fruit and vegetable farming within the study area.  相似文献   
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Environmental Science and Pollution Research - With the actual increasing interest for urban soils, the evaluation of soil contamination by trace elements and the dynamics of this contamination...  相似文献   
57.
Seed and fruit dispersal along watercourses favours the long-distance migration of invasive species, not only for aquatic or wetland species, but also for terrestrial wind-dispersed plants, like the Japanese knotweed. The present paper aims at investigating the role of watercourses in the dispersal of the knotweed due to its frequent occurrence on riverbanks and production of fertile achenes (type of fruit of the Japanese knotweed). This dispersal occurs along two steps after the fruits deposit on the water surface: floatation first and then sinking towards the bottom of the watercourse. Regarding the first step, the effects of agitation of the water, temperature, surface tension and luminosity on the achenes floatability are experimentally studied. While no influence of luminosity is observed, an increase of temperature greatly decreases the floating time. Floating time also decreases as the contact between water and the fruit is enhanced (through submersion of achenes, agitation of the water or lower surface tension). Regarding the second step, the fall velocity of the fruits in water at rest is measured and appears to be independent of the seed history (floating time). 3D helical motions are systematically observed with constant tangential velocity with respect to the falling velocity. The trajectory of the fruits in a shear flow is then measured and the evolution of their velocity components along the sinking process is discussed. Finally, the contribution of both steps to the long-distance migration of the seeds is estimated.  相似文献   
58.
Journal of Material Cycles and Waste Management - The use of food waste (FW) for the production of biofuels and value-added compounds is growing worldwide. However, the significant chemical...  相似文献   
59.
Forestry is a productive sector with significant effects on meeting national socio-economic and environmental functions as well as the improvement of rural livelihoods. Non-wood forest products (NWFPs) in particular have been widely advocated by conservation and development organisations as potential alternative livelihood strategies, particularly among vulnerable forest dependant households. Like in most tropical countries, NWFPs are relevant in the sustainable development of Kenya that is particularly endowed with important forest resources. Kenya hosts about 17 million ha of forested land (about 3.51% of the total Sub-Saharan Africa forest cover by 2000), of which about 16,865,000 ha is under natural forest (EarthTrends: Forests, grasslands and drylands, 2003). Outside the gazetted forests, there are other large tracks of forests in trust lands, including national parks and reserves, hill forest reserves and privately owned lands covering about 0.5 million ha (Kenya’s forest resource assessment in the EC-FAO Partnership Programme Report, 2000; The Kenya Forests Act, 2005). Woodlands, bushlands and wooded grasslands, mainly found in the arid and semi-arid lands cover 37.6 million ha, while forest plantations (started in 1946) cover about 170,000 ha of land (The Kenya forestry master plan, 1994–2020, 1994). In most NWFPs endowed regions of the country however, this socio-economic and environmental potential is still unrealized. We illustrate the latter by a case study of NWFPs use and management in four villages in Mbooni Division of Makueni District, Kenya. The division was chosen because of its relatively high NWFPs availability, particularly from South Mbooni forest that is located at a distance less than 5 km for an estimated 80% of the interviewed households. Data used for the analysis was collected through a fieldwork survey carried out on women (35+ years) in August, 2005. One hundred and sixty (160) NWFPs are harvested (from plant and animal species) and used mainly for food, income generation (supplemental) and medicinal purposes. A number of challenges limit women’s enjoyment of the full benefits from NWFPs exploitation, the overriding problem being their inadequacy (in quantity and/or quality). In this paper we discuss these commonly utilized and managed NWFPs plant species in Mbooni and their potential contribution to improved livelihoods and sustainable development in Mbooni, Kenya and Sub-Saharan Africa (SSA) in general.  相似文献   
60.
Although various studies have shown thatfarmers believe there is the need for a producer-ledinitiative to address the environmental problems fromagriculture, farmers in several Canadian provinceshave been reluctant to widely participate inEnvironmental Farm Plan (EFP) programs. Few studieshave examined the key issues associated with adoptingEFP programs based on farmers', as opposed to policymakers', perspectives on why producers are reluctantto participate in the program. A study adapting VanRaaij's (1981) conceptual model of the decision-makingenvironment of the firm, and prospect theory on valuefunctions associated with the gains and losses fromrisky choices can be used to characterize how farmersperceive potential risks in environmental farmplanning. This framework can be used to assert thatfarmers are concerned about risks of public disclosureof potentially incriminating environmental informationfrom farms because the EFP program requirements foridentification and extensive documentation of farminformation is perceived by farmers as facilitatingthe accessibility of environmental information to thepublic, and public investigative efforts. Although theEFP program does not explicitly generate informationabout the environmental conditions of a farm nor thedisclosure of such information to the public, itcreates the possibility of generating and divulgingpotentially incriminating information that the farmermay want to treat as confidential. Yet, alone, theserisks of public disclosure concerns should not preventfarmers from participating in the EFP. Awareness ofand participation in environmental farm planning canbe increased if farmers and policy makers understandwhat the risks are, and how they arise. Aspects of theEFP process that have the potential to generate riskof public disclosure concerns relate to farm reviews,documentation and record keeping, and correctiveaction plans. There are legal and policy instrumentsthat can offer various forms of protection and helpminimize such risks, and these need to be assessed.  相似文献   
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