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51.
Agroforestry in the Western Ghats (WG) of peninsular India and satoyama in rural Japan are traditional land-use systems with similar evolutionary trajectories. Some of their relevance was lost by the middle of the twentieth century, when modern agricultural technologies and urbanisation engineered shifts in emphasis towards maximising crop production. There has been, however, a resurgence of interest in traditional land-use systems recently, in view of their ability to provide ecosystem services. Both agroforestry and satoyama are thought to be harbingers of biological diversity and have the potential to serve as “carbon forests.” Carbon (C) stock estimates of the sampled homegardens in WG ranged from 16 to 36 Mg ha−1. Satoyama woodlands owing to variations in tree stocking and management conditions indicated widely varying C stocks (2–279 Mg ha−1). Agroforestry and satoyama also differ in nature, complexity, and objectives. While agroforestry involves key productive and protective functions, and adopts ‘intensive management’, the satoyama woodlands are extensively managed; understorey production is seldom a consideration. Differences in canopy architecture (multi-tiered structure of agroforestry vs. the more or less unitary canopy of satoayama) and land ownership pattern (privately owned/managed agroforestry holdings vs. community or local government or privately owned and mostly abandoned satoyamas) pose other challenges in the transfer and application of knowledge gained in one system to the other. Nonetheless, lessons learnt from satoyama conservation may be suitable for common pool resource management elsewhere in Asia, and aspects relating to understorey production in agroforestry may be relevant for satoyama under certain scenarios.  相似文献   
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Perchlorate is an inorganic anion that is used in solid rocket propellants, fireworks, munitions, signal flares, etc. The use of fireworks is identified as one of the main contributors in the increasing environmental perchlorate contamination. Although fireworks are displayed for entertainment, its environmental costs are dire. Perchlorates are also emerging as potent thyroid disruptors, and they have an impact on the ecology too. Many studies have shown that perchlorate contaminates the groundwater and the surface water, especially in the vicinity of fireworks manufacturing sites and fireworks display sites. The health and ecological impacts of perchlorate released in fireworks are yet to be fully assessed. This paper reviews fireworks as a source of perchlorate contamination and its expected adverse impacts.  相似文献   
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An attempt has been made in this paper to highlight some of environmental problems and suggest possible solutions for planning water resources development projects.  相似文献   
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This communication presents the results of an investigation conducted on color removal from a monoazo acid dye, C.I. Acid Red 88, by adsorption onto coal based sorbents like Lignite coal, Charfines and Bituminous coal and F-400 Activated carbon and by chemical coagulation employing Aluminum sulfate, Ferric chloride, Manganese sulfate, Manganese chloride and Barium chloride.  相似文献   
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选用101株分离自扁蓿豆、胡枝子、野豌豆、锦鸡儿属植物的根瘤菌菌株,进行了营养利用、抗生素抗性、耐逆性和酶活性测定等84个表型性状分析,发现分离自同种寄主植物的根瘤菌由于地理来源的不相同而存在着较大的多样性.通过数值分类,各已知种分别聚群,101株未知菌在84%的相似水平上分为4个各不同的群.根据1、2、3、4群菌的聚类情况,结合在不同水分梯度下采集的豆科牧草根瘤菌,结果发现除个别菌外,绝大部分菌株呈现随着水分梯度的不同,各菌以类群形式分布.证明土壤中水分含量对根瘤菌的分布有很大影响.  相似文献   
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This paper recognises the need for a revision of watershed development policy in India in relation to the planning of development interventions involving agricultural intensification and rainwater harvesting and the need for new approaches to assist the planning process. Building on, and using as an example, the results of biophysical and societal impact studies carried out on two watershed development projects in Karnataka three new management/dissemination tools, are suggested. These are (1) the web-based geographical information systems exploratory, climate land assessment and impact management tool dissemination tool for disseminating to policymakers and non-specialist stakeholders the downstream impacts of watershed interventions, (2) the ‘quadrant’ approach for ensuring that sustainability criteria are met and (3) Bayesian networks to investigate the biophysical and societal impacts of interventions. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue  相似文献   
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A waste product generated in the sugar industry in India has been converted into a cheap potential adsorbent. This has been characterised and utilized for the removal of chromium (VI) from synthetic and actual wastewater. The sorption efficiency decreases with increase in pH. Adsorption of Cr (VI) on bagasse fly ash follows the Freundlich and Langmuir isotherms and these have been used to obtain the thermodynamic parameters of the process. The sorption capacity of this adsorbent for chromium removal is found to be comparable to other low cost adsorbents.  相似文献   
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