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31.
China is an illustrative—and extreme—case of the difficulties of balancing the pursuit of economic, social, and environmental objectives. In 2003 it adopted a form of Strategic Environmental Assessment (SEA) for its plans and programs (referred to here as PEIA) with the aim of moving towards greater environmental sustainability. The literature has explored primarily the issue of methods and legal procedures. This research contributes to the analysis of PEIA through a different set of interpretative lens. Drawing on recent developments in the theory and practice of SEA, I propose a conceptualization of SEA effectiveness that combines direct and incremental impacts, and a need for context-specific systems as a way to focus on the relationship between assessment, planning, and their context, and thus maximize effectiveness. This framework underpins the analysis of China’s experience, which I explore with the help of interview material and the literature. The result is an evaluation of the strengths and weaknesses of PEIA in terms of its purpose, assessment concept, process, and methods. The detailed analysis of six aspects of the context helps explain the origin of such shortcomings, and identify opportunities for its improvement. I conclude defining elements of a context-specific system for SEA that seeks to maximize the opportunity for incremental, as well as direct, effectiveness in China.  相似文献   
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Induction of triploidy in aquatic organisms has increased worldwide in the last two decades, mostly because triploids have better growth than diploids. According to a physiological hypothesis, partial or total sterility of triploids allows the accumulation of reserves in muscle and other tissues instead of being transferred to the gonad. The present study analyzes lipid, protein, carbohydrate, and fatty acid levels in muscle and gonads of Nodipecten subnodosus triploids and diploids over 18 months from June 2001 to December 2002. An important increase in gonadosomatic index of diploids scallops was observed from May to June 2002 reaching the highest values in August. Such increase was not observed in triploid scallops. Changes in biochemical composition in female gonad were in general related to the accumulation of reserves during gonad development of diploid scallops. This accumulation was lower for triploid scallops, in accordance to their sterility, especially for carbohydrates and acylglycerides. Adductor muscle index as well as protein and carbohydrate levels in muscle increased in both ploidy groups during the reproductive period indicating no mobilization of reserves to sustain gonad development in both ploidy groups. These results partially support the physiological hypothesis on the advantage of triploids: in a rich food locality no mobilization of reserves is needed to sustain gametogenesis. This, together with a possible lower efficiency of energy assimilation at high food concentration for triploids, may be the reason for an apparent lack of superiority of N. subnodosus triploids in terms of adductor muscle growth. Only the levels of particular highly unsaturated fatty acids levels (namely 20:4n-6 and 20:5n-3) in muscle of diploid and triploid decreased during the reproductive period, indicating a possible transfer of selected fatty acids to gonads, even in triploids. The muscle of triploids has a slightly but significantly higher proportion of 22:6n-3 compared to diploids, which can have implications for the nutritional and commercial value of triploid adductor muscle.  相似文献   
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Journal of Polymers and the Environment - The use of agroindustry by-products as reinforcements and/or composites filler is an innovative and economically attractive option that is still under...  相似文献   
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Drainage of forested wetlands for increased timber production has profoundly altered the hydrology and water quality of their downstream waterways. Some ditches need network maintenance (DNM), but potential positive effects on tree productivity must be balanced against environmental impacts. Currently, no clear guidelines exist for DNM that strike this balance. Our study helps begin to prioritise DNM by: (1) quantifying ditches by soil type in the 68 km2 Krycklan Catchment Study in northern Sweden and (2) using upslope catchment area algorithms on new high-resolution digital elevation models to determine their likelihood to drain water. Ditches nearly doubled the size of the stream network (178–327 km) and 17% of ditches occurred on well-draining sedimentary soils, presumably making DNM unwarranted. Modelling results suggest that 25–50% of ditches may never support flow. With new laser scanning technology, simple mapping and modelling methods can locate ditches and model their function, facilitating efforts to balance DNM with environmental impacts.  相似文献   
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The increasing requirement for Solid Waste Management (SWM) has become a significant challenge for municipal authorities. A number of integrated systems and methods have introduced to overcome this challenge. Many researchers have aimed to develop an ideal SWM system, including approaches involving software-based routing, Geographic Information Systems (GIS), Radio-frequency Identification (RFID), or sensor intelligent bins. Image processing solutions for the Solid Waste (SW) collection have also been developed; however, during capturing the bin image, it is challenging to position the camera for getting a bin area centralized image. As yet, there is no ideal system which can correctly estimate the amount of SW. This paper briefly discusses an efficient image processing solution to overcome these problems. Dynamic Time Warping (DTW) was used for detecting and cropping the bin area and Gabor wavelet (GW) was introduced for feature extraction of the waste bin image. Image features were used to train the classifier. A Multi-Layer Perceptron (MLP) classifier was used to classify the waste bin level and estimate the amount of waste inside the bin. The area under the Receiver Operating Characteristic (ROC) curves was used to statistically evaluate classifier performance. The results of this developed system are comparable to previous image processing based system. The system demonstration using DTW with GW for feature extraction and an MLP classifier led to promising results with respect to the accuracy of waste level estimation (98.50%). The application can be used to optimize the routing of waste collection based on the estimated bin level.  相似文献   
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This article explores the potential for microhydro installations in Nepal to improve adaptive capacity in addition to their ability to mitigate greenhouse gas emissions. After explaining its methods of data collection—namely field research and research interviews—the article explores the climate change adaptation benefits of microhydro plants being promoted under the Renewable Energy Development Project (REDP). Besides displacing fossil fuels, in particular kerosene for lighting, microhydro electrification offers an effective way of improving community assets and bolstering social resilience (thereby enhancing the adaptive capacity of communities there). Our own survey of REDP project sites reveals how microhydro units have improved community income levels, equalized gender roles, enhanced access to education and information, and reduced migration patterns. The article concludes by highlighting three key lessons—the role of extensive community mobilization, proactive capacity building for efficient electricity use, and the need for comprehensiveness—for those wishing to adapt to climate change in other rural and developing economies.  相似文献   
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Summary Anting is a behavior common among passerine birds, yet its function is unknown. The behavior consists of a highly stereotyped set of movements which start when a bird picks up an ant, usually one which sprays formic acid as a defense, and sweeps it with frenzied motions through its feathers. The bird will often also eat the ant. As formic acid is toxic, we have tested the food-preparation hypothesis, that is, that the birds are anting to remove a distasteful or toxic substance from the ant before eating it. In a pair of experiments on starlings, Sturnus vulgaris, we have found evidence in support of this hypothesis. Correspondence to: O.P. Judson  相似文献   
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