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ABSTRACT

The success of ecological restoration efforts is tightly coupled with the effectiveness of many U.S. environmental policies. Yet scholars have raised questions about the ability of restoration to produce intended results. We use a case study of tidal wetland restoration planning in Oregon to examine how neoliberal environmental governance exercises influence through a set of knowledge politics that produces subpar outcomes. We present three main findings: (1) restoration policies produce a restoration economy based on a conception of wetland as commodity (2) practitioners in this restoration economy exhibit competitive behavior resulting in a piecemeal rather than a landscape approach to restoration; and (3) limited monitoring prevents changes to existing policies. Practitioners offer insight into the challenge of treating wetlands as a commodity and call for more monitoring to challenge the assumptions of hegemonic knowledge practices that reinforce a neoliberal environmental governance regime. The divergent ideas of reflexive practitioners, though not yet manifest as action, show where changes to restoration governance might be possible.  相似文献   
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The necessity of incorporating societal and environmental concerns into publicly funded agricultural initiatives in research, extension, and practice is increasingly evident. Agriculturalists are urged to acknowledge and respond to societal concerns before an insensitive and largely ill-informed urban majority assumes a dominant posture in agricultural policy. In recent history, the availability of unrealistically cheap energy encouraged the evolution of a form of commercial agriculture unfettered by sound ecological principles. At present, external, resource-intensive intervention of increasing magnitude is needed to compensate for the apparent ecological instability generated by practices such as intensive cereal management or conservation tillage practices. Polarization of the enterprises of plant and animal agriculture to enable centralized, concentrate-intensive, confinement feeding has disrupted the natural cycling of nutrients and carbon in the soil, encouraged the withdrawal of perennial forages from crop rotations, and invoked a widely ramifying network of agricultural and societal problems. Solutions to these problems must evolve from a holistic and far-reaching appraisal of causes, rather than from a piecemeal approach to individual symptoms.  相似文献   
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The application of anaerobically processed animal manure to maintain adequate levels of organic matter in arid soils is becoming a common practice. The purpose of this study was to characterize two farm manure products as compared with municipal waste compost (MWC). The anaerobic processing to obtain a biogas manure (BM) product was much faster (25 d) than the aerobic composting of farmyard manure (FYM) (90 d). Drying by three different methods (solar-drying, vacuum-drying at 45 degrees C, and freeze-drying) did not affect the quality of BM. Based on the chemical characteristics, FYM and BM products were comparable, and, containing less ash (30%) and heavy metals (50 mg Pb kg(-1)), seemed superior to MWC that contained 65% ash and 108 mg Pb kg(-1). On the other hand, MWC had higher C content (69.9%), lower acidity (15.04 mol kg(-1)), and higher exothermic peaks (300-460 degrees C) than BM and FYM (50% C, 20 mol kg(-1), and 275-450 degrees C, respectively), thus showing a greater extent of humification. Also, when the organic materials were incubated with arid soils and monitored for mean residence times (MRT), MWC was slightly more resistant to decomposition (MRT 175-180 d) than BM or FYM (MRT 161-166 d). The observed differences, however, were too small to dismiss any of the products as a valuable material for land applications to improve soil quality. In view of the results obtained, MWC may be considered an adequate substitute for BM or FYM, whenever the latter are in short supply.  相似文献   
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This study evaluates the spatial patterns of land occupation and their relationship to water quality in the Cuiabá River watershed, one of the main affluents of the Pantanal floodplain. The impact of farming and other land occupation forms were studied using a three year time series. Monitoring included 15 parameters at 21 stations with a total of 1266 different samples. Ten stations along the Cuiabá River were ordinated by Principal Component Analysis (PCA). For an exploratory analysis in the spatial domain, sub-basins of the Cuiabá watershed were classified according to mean concentrations of selected water quality parameters. Supervised classification of digital Landsat ETM imagery and standard GIS techniques were applied to parameterize land use and occupation according to a watershed scale. Redundancy Analysis (RDA) was then used to evaluate impacts of environmental and socio-economic factors on water quality.A Cuiabá headwater station only shows slightly elevated total coliform counts and concentrations of nutrients in the river after it passes regions of extensive cattle farming. After the confluence with the Manso River, nutrient and COD concentrations increase significantly, receiving loads from sub-basins under intensive agricultural land use, with mean annual concentrations up to 1.74 mg/L of total nitrogen (Kjedahl). Sub-watersheds with intensive fishing culture activities were shown to have significant impact on nitrogen concentrations, reaching mean concentrations of 2.66 mg/L of total nitrogen in the affluents. Most serious biological and chemical water pollution can be observed at stream outlets in the urban agglomeration of Cuiabá/Várzea Grande. Affluent pollution is reflected in the water quality of the Cuiabá River: subsequent monitoring stations in the urban area are ordinated on a gradient of increasing degradation of chemical and biological water quality. The auto-depuration capacity of the Cuiabá River is intact, but elevated concentrations of Phosphorous and Chemical Oxygen Demand can be observed as far away as the Pantanal floodplain, about 120 km downstream from the urban agglomeration.  相似文献   
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无论从程序上还是内容上,公众参与对开展可持续的环境评价都是必不可少的。听证会是公众参与最便捷的途径,但其也面临着各方的政治压力,需快速有效地开展。听证会记录的保存为研究环评公众参与提供了最原始的数据,但数据分析需要大量的时间和精力,不利于开展经常需要的深度定性分析。自动内容分析技术提供了分析听证会记录的快速、可复制、可归纳的系统方法,包括计算机编程脚本的重要开发和应用,能合成大量的文档信息。此文通过加拿大西北部麦肯齐山谷Prairie Creek(EA0809-002;2008—2011)和Nico(EA0809-004;2009—2013)两个听证会案例研究,证实了此技术的潜在功用。通过对分析结果的解读,对自动内容分析技术进行了评估,并预估了将其广泛应用于环境评价研究和实践的可能性。  相似文献   
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