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591.
Multi-tenure reserve networks aim to connect areas managed for biodiversity conservation across public and private land and address the impacts of fragmentation on both biotic and social systems. The operation and function of Australian multi-tenure reserve networks as perceived by their land managers was investigated. Overall, the conservation of natural assets was the most frequently reported primary reason for involvement in a network. The perceived aims of the respective networks largely reflected the response identified for involvement and management. Over 88% of managers considered their involvement in multi-tenure reserve networks to be a positive or very positive experience. A lack of resources and time for management were considered major limitations of these networks. The majority (80%) of private land managers within networks were willing to be included in a national reserve system of conservation lands. As the Australian National Reserve System currently incorporates mostly public land, these findings have important and potentially positive implications for a greater role for protected private land. 相似文献
592.
Hirohisa Kishino Kazunori Hanyu Masako Yamashita Chikio Hayashi 《Resources, Conservation and Recycling》1999,26(3-4)
This paper compares the recycling attitudes of consumers in Germany and Japan, based on our nationwide questionnaires. We analyzed consumption behavior as well as recycling behavior in narrow sense, because it is important to study the former to see how the supply of recycled materials is balanced with the demand, particularly in Japan which exports little recycled materials. Toilet paper was adopted as a specific good for study, because consumers have options of buying virgin products and recycled products. It was found that German households pay for waste collection specifically and have higher recycling rates than Japanese households. On the other hand, similar figures in German and Japanese consumers were observed with regard to consumption of recycled products. Their purchasing criteria and preference on virgin and recycled products of toilet paper were examined by self-report and blind test with 2×2 experimental design for toilet paper (German versus Japanese, virgin versus recycled). Blind test showed that people prefer domestic and virgin products in both countries. Half of respondents rating virgin products guessed that the products contained recycled material. For Japanese, the material of the sample toilet paper, made from virgin pulp, seems to be a more determining factor than the nationality of products, i.e. made in Japan. On the other hand, for Germans, the domestic nature seems to be a more dominant factor than the material, i.e. made from virgin material. Canonical discriminant analysis in conjunction with logistic regression based on self-reporting data detected the characters ‘multiplied’, ‘appearance’ and ‘brand’ as major factors making the difference in preference between the two countries. The possible reasons causing the similarity and dissimilarity between the two countries are discussed with reference to the background history. 相似文献
593.
594.
Ranjan S. Muttiah Raghavan Srinivasan Peter M. Allen 《Journal of the American Water Resources Association》1997,33(3):625-630
ABSTRACT: The cascade correlation neural network was used to predict the two-year peak discharge (Q2) for major regional river basins of the continental United States (US). Watersheds ranged in size by four orders of magnitude. Results of the neural network predictions ranged from correlations of 0.73 for 104 test data in the Souris-Red Rainy river basin to 0.95 for 141 test data in California. These results are improvements over previous multilinear regressions involving more variables that showed correlations ranging from 0.26 to 0.94. Results are presented for neural networks trained and tested on drainage area, average annual precipitation, and mean basin elevation. A neural network trained on regional scale data in the Texas Gulf was comparable to previous estimates of Q2 by regression. Our research shows Q2 was difficult to predict for the Souris-Red Rainy, Missouri, and Rio Grande river basins compared to the rest of the US, and acceptable predictions could be made using only mean basin elevation and drainage areas of watersheds. 相似文献
595.
欧美等发达国家在促进循环产业发展、推行资源综合利用方面积累了丰富经验。其相关政策和手段体现了世界先进的资源管理思想和方法。对发达国家资源综合利用法律体系、政策制度、生产者延伸责任制、利益机制和技术体系等多方面进行了概要的分析与总结,以期对我国资源综合利用产业化发展提供一定的借鉴。 相似文献
596.
597.
某公司对镀镍线产生的含镍废水,依据废水的性质和来源,进行分类回收利用。对逆流漂洗废水采用槽边回用的方式,经离子交换处理后回用于逆流漂洗槽;对综合废水收集处理,对部分出水经深度处理后,回用于镀镍线前处理、废气净化以及废水处理药剂配制等,实现水资源的节约。通过废水的回收利用,公司实现节水400 m3/d,减少废水处理量220 m3/d,减少废水排放量约300 m3/d,具有较好的环境效益和经济效益。 相似文献
598.
随着科技的快速发展,电子产品数量的急剧增加及其使用周期的不断缩短,全球面临着前所未有的电子废物产生浪潮。一种数量巨大的典型电子废弃物-废旧印刷线路板如何实现绿色、低能耗的处理已成为当前电子废弃物处理中关键问题之一。利用微生物湿法冶金技术将废旧印刷线路板中金属浸出,制备高纯金属,已成为21世纪电子废物处理的前沿技术,同时电子废物的微生物湿法冶金机制探讨已成为近年来的研究热点。本文重点分析微生物湿法冶金处理废旧印刷线路板浸提过程中的微生物种类、影响浸提因素、微生物的浸出机制以及今后需要继续研究的问题。 相似文献
599.
随着人们淘汰的电子废弃物日益增多,电子废弃物对环境的污染越来越严重,电子废弃物虽然含有大量危险有害化学物质,但其中的稀贵金属却具有很好的回收利用价值,文章通过电子废弃物资源循环体系研究,提出了建立电子废弃物法律法规体系、政府职能体系、资源回收体系、绿色行为体系的新思路,解决了电子废弃物资源循环利用过程中存在的法律漏洞问题、政府监督和管理缺位问题、电子废弃物回收路径不畅通问题和人们绿色消费意识不强等问题. 相似文献
600.
基于ABR-MBR组合工艺优化反硝化除磷性能的研究 总被引:5,自引:4,他引:1
基于ABR-MBR一体化反应器,以低C/N比生活污水为研究对象,结合厌氧折流板反应器(ABR)微生物相分离的特性,通过优化与ABR优质供碳和脱氮除磷相耦合的膜生物反应器(MBR)硝化液回流比以实现高效反硝化除磷,并对ABR-MBR污泥回流比进行优化.结果表明,在ABR段有机负荷为2.0 kg·(m3·d)-1、系统的水力停留时间(HRT)为9 h、泥龄(SRT)为15 d,系统获得最优的处理效果时的硝化液回流比和污泥回流比分别为300%和100%.其中TN和溶解性PO3-4-P平均去除率分别达84%和94%,ABR中反硝化除磷量可达系统总去除量的87%,平均出水TN和溶解性PO3-4-P浓度分别为12.98 mg·L-1和0.43 mg·L-1. 相似文献