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121.
Biological, chemical, and physical attributes of aquatic ecosystems are often strongly influenced by groundwater sources. Nonetheless, widespread access to predictions of subsurface contributions to rivers, lakes, and wetlands at a scale useful to environmental managers is generally lacking. In this paper, we describe a neighborhood analysis approach for estimating topographic constraints on spatial patterns of recharge and discharge and discuss how this index has proven useful in research, management, and conservation contexts. The Michigan Rivers Inventory subsurface flux model (MRI-DARCY) used digital elevation and hydraulic conductivity inferred from mapped surficial geology to estimate spatial patterns of hydraulic potential. Model predictions were calculated in units of specific discharge (meters per day) for a 30-m2-cell raster map and interpreted as an index of potential subsurface water flux (shallow groundwater and event through-flow). The model was evaluated by comparison with measurements of groundwater-related attributes at watershed, stream segment, and local spatial scales throughout Lower Michigan (USA). Map-based predictions using MRI-DARCY accounted for 85% of the observed variation in base flow from 128 USGS gauges, 69% of the observed variation in discharge accrual from 48 river segments, and 29% of the residual variation in local groundwater flux from 33 locations as measured by hyporheic temperature profiles after factoring out the effects of climate. Although it does not incorporate any information about the actual water table surface, by quantifying spatial variation of key constraints on groundwater-related attributes, the model provides strata for more intensive study, as well as a useful spatial tool for regional and local conservation planning, fisheries management, wetland characterization, and stream assessment.  相似文献   
122.
论生态园林及其建设的基本原则   总被引:1,自引:0,他引:1  
生态园林是城市绿地建设的新思维,也是生态学具体应用的实践.生态园林建设应遵循生态优先、物种多样性保护和重建、因地制宜、处理好种间关系、建立群落自维持机制、重视生态文化内涵等六要素.  相似文献   
123.
124.
采用《环境影响评价技术导则非污染生态影响》(HJ/T 19-1997)推荐的景观生态学评价方法,应用景观生态学的基本原理,通过对景观多样性指数、景观优势度和人工干扰指数等3类景观格局指数的计算及对比,从景观空间结构、异质性、恢复能力等方面,预测建设项目实施对生态环境的影响程度,并提出工程项目建设应注意的问题和采取的措施.  相似文献   
125.
ABSTRACT: This article, based on a review of the literature, examines several aspects of the rhizosphere ecology of submersed macrophytes. These include the role of the rhizosphere microflora in affecting plant growth through influences on nutrient availability and production of plant growth regulating compounds. Interactions between components of the sediment microflora and plant roots are considered in relation to plant nitrition and growth. Possible applications of this information to the management of submersed macrophytes are considered.  相似文献   
126.
探讨了“乡村聚落”和“乡村聚落生态系统”等基本概念以及乡村聚落生态研究的主要内容 ,包括乡村聚落生态评价和生态区划、对特殊聚落的研究、乡村聚落的选址以及乡村聚落生态与生态村建设 ,以期推动乡村聚落生态研究的发展。  相似文献   
127.
将社会库存、水资源足迹和污染足迹纳入生态足迹需求计算模型,改进和完善了生态足迹需求理论与方法. 依据海南省统计年鉴资料,计算并分析了海南省1952—2004年的生态足迹,揭示了海南省52年来对自然资源利用的状况和特征.结果表明:①海南省可再生资源生态足迹占总生态足迹的绝大部分,二者呈同步增长态势,但距离在加大;②海南省对自然资源的利用主要集中于海洋、耕地和能源用地,对草地、林地、淡水水域和建设用地的利用强度相对较小,对水资源的利用强度明显减少;③海南省万元GDP生态足迹呈下降趋势,资源利用效益逐步提高. 海南省生态足迹动态变化的原因包括:①海南省生态足迹的变化是海南省经济生产和消费结构变化的结果,经济和人口增长导致资源的大量消耗,是造成生态足迹不断上升的主要原因;②海南省经济生产的主要方式是农业,农业问题是海南省可持续发展需要解决的首要问题;③海南省对耕地、林地和水资源的利用逐步下降,近几年对水域特别是海洋动物性食品的需求急剧增加,这是居民收入水平上涨的结果。   相似文献   
128.
Corporate environmental responsibility in the supply chain   总被引:1,自引:0,他引:1  
A continuing trend in outsourcing increases the complexity of supply chains. Global supply chains extend over numerous echelons of countless companies. In parallel, the company-internal view on corporate environmental responsibility is being challenged as customers and legislation alike broaden a company's environmental responsibility to include organisations' upstream as well as downstream in the supply chain. Therefore, the aim of this study was to examine corporate environmental responsibility beyond corporate boundaries, i.e. in the supply chain. A cross-industrial study based on 16 case studies in Finnish trans-national corporations sheds light on various dimensions of corporate environmental responsibility upstream and downstream of product and process supply chains. Conclusions were drawn for corporate environmental responsibility as well as for the role of supply chain management in extending environmental demand over several echelons and diverse industries.  相似文献   
129.
Wildlife-road conflict has profound negative impacts on both wildlife populations and society. Despite a long-held understanding of this problem, in most regions the wildlife-management strategies (WMS) available to mitigate this conflict are still relatively underutilized. This study examines the implementation of these strategies into road infrastructure, using Southern Ontario as a case study, in order to develop an understanding of what leads to successful WMS implementation. The project management concept of critical success factors was applied and interviews with project decision-makers and key stakeholders were conducted. Nine factors were identified and a comparison between a ‘smooth’ and ‘rough’ project is used to illustrate the cumulative effects that these factors, and their interrelationships, have on project implementation success. Practitioners can use these findings to evaluate WMS projects based on likelihood of success and allocate resources accordingly, ultimately leading to increased chances of implementation and overall benefit to conservation and society.  相似文献   
130.
Many species that inhabit seasonally ponded wetlands also rely on surrounding upland habitats and nearby aquatic ecosystems for resources to support life stages and to maintain viable populations. Understanding biological connectivity among these habitats is critical to ensure that landscapes are protected at appropriate scales to conserve species and ecosystem function. Biological connectivity occurs across a range of spatial and temporal scales. For example, at annual time scales many organisms move between seasonal wetlands and adjacent terrestrial habitats as they undergo life‐stage transitions; at generational time scales, individuals may disperse among nearby wetlands; and at multigenerational scales, there can be gene flow across large portions of a species’ range. The scale of biological connectivity may also vary among species. Larger bodied or more vagile species can connect a matrix of seasonally ponded wetlands, streams, lakes, and surrounding terrestrial habitats on a seasonal or annual basis. Measuring biological connectivity at different spatial and temporal scales remains a challenge. Here we review environmental and biological factors that drive biological connectivity, discuss implications of biological connectivity for animal populations and ecosystem processes, and provide examples illustrating the range of spatial and temporal scales across which biological connectivity occurs in seasonal wetlands.  相似文献   
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