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991.
This paper introduces an integrated water management model at the industrial park level. It suggests four approaches to water
management: first, direct water reuse among users; second, water reuse among users by blending with freshwater; third, water
reuse between users and a wastewater treatment plant; and fourth, groundwater recharge by reclaimed wastewater or other feasible
applications in order to optimize the overall water efficiency. The model results in a comprehensive management methodology
for optimizing water resources within an industrial park, seeking potential water reuse among industries, and incorporating
the size and cost of reclaimed wastewater delivery systems. A case study is employed to test the model’s feasibility. An economic
analysis of the optimized water use network is also carried out, showing the potential water and cost savings. 相似文献
992.
Coastal waters have been significantly influenced by increased inputs of nutrients that have accompanied population growth
in adjacent drainage basins. In Tampa Bay, Florida, USA, the population has quadrupled since 1950. By the late 1970s, eutrophic
conditions including phytoplankton and macroalgal blooms and seagrass losses were evident. The focus of improving Tampa Bay
is centered on obtaining sufficient water quality necessary for restoring seagrass habitat, estimated to have been 16,400
ha in 1950 but reduced to 8800 ha by 1982. To address these problems, targets for nutrient load reductions along with seagrass
restoration goals were developed and actions were implemented to reach adopted targets. Empirical regression models were developed
to determine relationships between chlorophyll a concentrations and light attenuation adequate for sustainable seagrass growth. Additional empirical relationships between
nitrogen loading and chlorophyll a concentrations were developed to determine how Tampa Bay responds to changes in loads. Data show that when nitrogen load
reduction and chlorophyll a targets are met, seagrass cover increases. After nitrogen load reductions and maintenance of chlorophyll a at target levels, seagrass acreage has increased 25% since 1982, although more than 5000 ha of seagrass still require recovery.
The cooperation of scientists, managers, and decision makers participating in the Tampa Bay Estuary Program’s Nitrogen Management
Strategy allows the Tampa Bay estuary to continue to show progress towards reversing many of the problems that once plagued
its waters. These results also highlight the importance of a multi-entity watershed management process in maintaining progress
towards science-based natural resource goals. 相似文献
993.
994.
目前企业化经营已被越来越多地运用于农业开发的生产管理中。本文阐述了农业开发中企业化经营形式及其重要性,分析了当前企业化经营优势尚未充分发挥的原因,提出了加强农业开发企业化管理的对策。 相似文献
995.
Laura A. German Berhane Kidane Riziki Shemdoe 《Environment, Development and Sustainability》2006,8(4):535-552
Natural resource degradation in highland regions is of increasing concern to the global community due to its role in aggravating poverty and the loss of environmental services to local and downstream users. The integration of trees into smallholder farming systems has been promoted as a means to enhance rural livelihoods while reversing the degradation of soil, water, biodiversity and related environmental services. Yet in addition to these benefits, negative impacts of trees on certain stakeholders or system components have also accompanied such efforts—suggesting that important trade-offs accompany afforestation. This paper presents a methodology for diagnosing problems stemming from cultivation of certain tree species in specific landscape niches. Data derived from the application of this methodology in two sites in the eastern African highlands are presented. Participatory diagnoses of landscape-level problems suggest that the negative impact of trees on water resource availability and crop yield are of critical concern to smallholder farmers. Ethnoecological data highlight the properties of different tree species that determine their suitability to specific farm and landscape niches. These data point to important opportunities for more socially- and environmentally-optimal integration of indigenous and exotic tree species into agricultural landscapes, and highlight the critical importance of local knowledge in forging solutions appropriate to contemporary realities. 相似文献
996.
在企业环境管理运用控制论实施污染防治全过程控制,来提高清洁生产水平,降低物耗,能耗,提高资源利用率,完善保护环境的自我约束机制,落实环境综合整治定量考核,以达到发展生产,提高经济效益和改善环境的目的。 相似文献
997.
文章分析了西北地区目前水资源现状、水资源质量状况和开发利用等情况,并对水资源供需发展趋势作出预测。根据西北地区水环境安全面临的严峻形势,提出了构建西北地区水环境安全体系的对策和建议。 相似文献
998.
Because American national forests are managed for all citizens, it is important that researchers explore the differences and
similarities between citizens living both near and far from publicly managed land. We surveyed residents living at various
distances from nationally managed land to collect resident perceptions of different forest fire-management techniques, to
determine public preferences for these techniques, and to examine the motivations behind these preferences. Participants both
close to and far away from national forests tended to favor a multipronged approach to fire management by preferring the use
of a combination of two or more fire-management techniques. There were no significant differences by proximity in participants’
self-rated emotions, types of fire-management techniques preferred, or the reasons and rationales for their preferred fire-management
technique(s), indicating that the proximity variable may not be as significant as previously thought. 相似文献
999.
面向土木工程学科的安全工程课程探讨 总被引:2,自引:1,他引:1
为促进建设工程安全生产,针对土木工程学科高等教育,笔者采用文献检索和相关学科比较研究方法,探讨了建设安全工程课程设置原则与课程内容。分析表明:土木工程学科开设安全工程课程,为建设工程安全生产培养合格技术人才,是实现建设工程安全生产长效机制的重要条件;课程设置应以"以人为本,安全第一""安全是效益"的观念、"建筑安全,百年大计"的思想、防灾、环保、安全宜居的建筑理论、建筑安全工程与安全科学技术相结合的实战能力培养为原则;面向土木工程学科的安全工程课程知识点应包括:安全法规,事故致因原理与事故规律,职业健康安全管理体系,建筑设计及施工项目的安全性评价,安全监理,事故案例与实践能力教学等。 相似文献
1000.
基于OSHMS的煤矿模糊综合安全评价管理模型的建立 总被引:1,自引:1,他引:0
针对目前我国煤矿企业安全管理现状,以一种全新的思路结合职业安全健康管理体系(OSHMS)的系统化体系结构及其先进之处,以预防为主,持续改进为动力,建立了基于生产过程的绩效测量、人员职责分配、运行控制和风险管理为核心的4个主要因素的安全评价管理模型;并以此为指导建立安全评价指标体系框架,运用模糊综合安全评价的方法对指标体系进行合成;最后,结合矿井生产过程中的供电系统,对淮南潘三矿现场进行实例应用,证明其可行性。该管理模型对煤矿企业安全管理有推广和借鉴意义,可望为煤矿企业通过安全管理实现科技兴安提供一种更可靠,更有效的安全管理方法。 相似文献