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991.
为优化金属矿山矿井通风系统及辅助决策设计,弥补常用矿井通风仿真解算软件在环境监测、实时解算和辅助决策方面的不足,基于矿井通风理论、环境监测、计算机与通信技术开发矿井通风三维仿真辅助决策系统。提出通过利用实时监测到的井下通风环境参数(风量、风速等)和已存储在系统数据库里的巷道参数,实现对矿井通风网络实时解算,并将其应用到山金阿尔哈达矿井通风系统中。结果表明:矿井通风三维仿真辅助决策系统同步实现了山金阿尔哈达矿井通风系统的环境监测、风网实时解算和三维仿真模拟,提高了其矿井通风管理水平,为矿井通风系统改造优化设计和矿井向深部中段延伸时的通风系统设计提供辅助决策依据。  相似文献   
992.
Many frameworks have been used to identify environmental flows for sustaining river ecosystems or specific taxa in the face of widespread flow alteration. However, these frameworks largely focus on identifying suitable flows and often ignore the important links between management actions, resulting flows, and valued ecosystem or social responses. Structured decision making (SDM) could assist the comparison of environmental flows by providing a mature framework to link management actions to objectives via environmental flow science. We describe SDM and illustrate its application using a case study focused on comparing environmental flow scenarios for the mainstem Willamette River, Oregon. In a short timeframe, SDM was applied to identify objectives, develop empirical and expert opinion‐based models, and compare flow scenarios while accounting for interannual flow variability and partial controllability. No scenario was clearly preferred based on available knowledge, largely because river flows could only be partially controlled through dam operations. Participants agreed that SDM was useful for comparing alternative dam operations, but that refined predictive models and additional objectives were needed to better inform basinwide flow decisions. In our view, SDM can provide more realistic comparisons of environmental flows by accounting for partial controllability and uncertainty, which may result in greater implementation of available flow management actions.  相似文献   
993.
多风机多级机站通风系统优化的模糊群体决策法   总被引:5,自引:3,他引:2  
矿井通风系统是一个复杂的非线性系统,具有随机性、模糊性和不确定性特征。为了实现矿井通风的系统安全,对系统的安全性进行了定性、定量的预测分析和安全评价。按目标分层,用分层模糊优选理论对矿井通风系统设计方案进行优选,分层时允许评价因素重叠,从而便于确定目标与评价因素的权重。对矿井通风系统建立了多个设计方案的评判指标体系,并应用模糊群体决策确定矿井通风系统方案评判指标的权值,研究成果已应用于中条山有色金属公司胡家峪铜矿通风系统优化研究中,获得了满意的结果。  相似文献   
994.
文章介绍了在环境工程中运用技术经济学的方法和内容,对环境工程项目的技术可行性和经济合理性进行综合评价,从而使环境工程投资决策建立在科学分析的基础上。  相似文献   
995.
长江流域生态环境对洪涝影响的评价   总被引:6,自引:2,他引:4  
长江流域的生态环境问题近年来变得越来越严重,其集中表现为:人口急剧增长的情况下,土地资源过度利用和不合理的开发,使生态环境的脆弱性增强,造成生态环境的恶化,结果导致洪水威胁加剧。本文通过对长江流域生态环境问题的分析,提出目前存在的问题是上游森林的过度开发、毁林开荒、陡坡开荒造成水土流失,增加了中下游河湖的泥沙淤积;中下游地区盲目围湖造田,占用行洪洲滩,湿地生态环境遭到破坏,造成水调蓄面积减少。最后就生态环境问题对洪涝的影响进行了评价。  相似文献   
996.
主要讨论了桉树造林整地方式──全垦与带垦对桉树生长的影响,以及对土壤侵蚀、土壤养分和土壤物理性质的影响.研究结果表明,改全垦为带垦对防止桉树人工林地力衰退有积极作用.  相似文献   
997.
We conducted synoptic surveys over three seasons in one year to evaluate the variability in water sources and geochemistry of an urban river with complex water infrastructure in the state of Utah. Using stable isotopes of river water (δ18O and δ2H) within a Bayesian mixing model framework and a separate hydrologic mass balance approach, we quantified both the proportional inputs and magnitude of discharge associated with “natural” (lake, groundwater, and tributary inputs) and “engineered” (effluent and canal inflows) sources. The relative importance of these major contributors to streamflow varied both spatially and seasonally. Spatiotemporal patterns of dissolved oxygen, temperature, pH, calcium, chloride, nitrate, and orthophosphate indicated seasonal shifts in dominant sources of river water played an important role in determining water quality. We show although urban rivers are clearly influenced by novel water sources created by water infrastructure, they continue to reflect the imprint of “natural” water sources, including diffuse groundwater. Resource managers thus may need to account for the quantity of both surface waters and also historically overlooked groundwater inputs to address water quality concerns in urban rivers.  相似文献   
998.
Controlling the spread of invasive species, pests, and pathogens is often logistically limited to interventions that target specific locations at specific periods. However, in complex, highly connected systems, such as marine environments connected by ocean currents, populations spread dynamically in both space and time via transient connectivity links. This results in nondeterministic future distributions of species in which local populations emerge dynamically and concurrently over a large area. The challenge, therefore, is to choose intervention locations that will maximize the effectiveness of the control efforts. We propose a novel method to manage dynamic species invasions and outbreaks that identifies the intervention locations most likely to curtail population expansion by selectively targeting local populations most likely to expand their future range. Critically, at any point during the development of the invasion or outbreak, the method identifies the local intervention that maximizes the long‐term benefit across the ecosystem by restricting species’ potential to spread. In so doing, the method adaptively selects the intervention targets under dynamically changing circumstances. To illustrate the effectiveness of the method we applied it to controlling the spread of crown‐of‐thorns starfish (Acanthaster sp.) outbreaks across Australia's Great Barrier Reef. Application of our method resulted in an 18‐fold relative improvement in management outcomes compared with a random targeting of reefs in putative starfish control scenarios. Although we focused on applying the method to reducing the spread of an unwanted species, it can also be used to facilitate the spread of desirable species through connectivity networks. For example, the method could be used to select those fragments of habitat most likely to rebuild a population if they were sufficiently well protected.  相似文献   
999.
There is current debate about the potential for secondary regrowth to rescue tropical forests from an otherwise inevitable cascade of biodiversity loss due to land clearing and scant evidence to test how well active restoration may accelerate recovery. We used site chronosequences to compare developmental trajectories of vegetation between self‐organized (i.e., spontaneous) forest regrowth and biodiversity plantings (established for ecological restoration, with many locally native tree species at high density) in the Australian wet tropics uplands. Across 28 regrowth sites aged 1–59 years, some structural attributes reached reference rainforest levels within 40 years, whereas wood volume and most tested components of native plant species richness (classified by species’ origins, family, and ecological functions) reached less than 50% of reference rainforest values. Development of native tree and shrub richness was particularly slow among species that were wind dispersed or animal dispersed with large (>10 mm) seeds. Many species with animal‐dispersed seeds were from near‐basal evolutionary lineages that contribute to recognized World Heritage values of the study region. Faster recovery was recorded in 25 biodiversity plantings of 1–25 years in which wood volume developed more rapidly; native woody plant species richness reached values similar to reference rainforest and was better represented across all dispersal modes; and species from near‐basal plant families were better (although incompletely) represented. Plantings and regrowth showed slow recovery in species richness of vines and epiphytes and in overall resemblance to forest in species composition. Our results can inform decision making about when and where to invest in active restoration and provide strong evidence that protecting old‐growth forest is crucially important for sustaining tropical biodiversity.  相似文献   
1000.
Stakeholders’ nonmaterial desires, needs, and values often critically influence the success of conservation projects. These considerations are challenging to articulate and characterize, resulting in their limited uptake in management and policy. We devised an interview protocol designed to enhance understanding of cultural ecosystem services (CES). The protocol begins with discussion of ecosystem‐related activities (e.g., recreation, hunting) and management and then addresses CES, prompting for values encompassing concepts identified in the Millennium Ecosystem Assessment (2005) and explored in other CES research. We piloted the protocol in Hawaii and British Columbia. In each location, we interviewed 30 individuals from diverse backgrounds. We analyzed results from the 2 locations to determine the effectiveness of the interview protocol in elucidating nonmaterial values. The qualitative and spatial components of the protocol helped characterize cultural, social, and ethical values associated with ecosystems in multiple ways. Maps and situational, or vignette‐like, questions helped respondents articulate difficult‐to‐discuss values. Open‐ended prompts allowed respondents to express a diversity of ecosystem‐related values and proved sufficiently flexible for interviewees to communicate values for which the protocol did not explicitly probe. Finally, the results suggest that certain values, those mentioned frequently throughout the interview, are particularly salient for particular populations. The protocol can provide efficient, contextual, and place‐based data on the importance of particular ecosystem attributes for human well‐being. Qualitative data are complementary to quantitative and spatial assessments in the comprehensive representation of people's values pertaining to ecosystems, and this protocol may assist in incorporating values frequently overlooked in decision making processes.  相似文献   
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