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361.
Ecosystem‐based management of the Laurentian Great Lakes, which spans both the United States and Canada, is hampered by the lack of consistent binational watersheds for the entire Basin. Using comparable data sources and consistent methods, we developed spatially equivalent watershed boundaries for the binational extent of the Basin to create the Great Lakes Hydrography Dataset (GLHD). The GLHD consists of 5,589 watersheds for the entire Basin, covering a total area of approximately 547,967 km2, or about twice the 247,003 km2 surface water area of the Great Lakes. The GLHD improves upon existing watershed efforts by delineating watersheds for the entire Basin using consistent methods; enhancing the precision of watershed delineation using recently developed flow direction grids that have been hydrologically enforced and vetted by provincial and federal water resource agencies; and increasing the accuracy of watershed boundaries by enforcing embayments, delineating watersheds on islands, and delineating watersheds for all tributaries draining to connecting channels. In addition, the GLHD is packaged in a publically available geodatabase that includes synthetic stream networks, reach catchments, watershed boundaries, a broad set of attribute data for each tributary, and metadata documenting methodology. The GLHD provides a common set of watersheds and associated hydrography data for the Basin that will enhance binational efforts to protect and restore the Great Lakes.  相似文献   
362.
Oyster farmers depend on good water quality. Activities upstream from estuaries result in externalities that impact water quality. Over the last 10 years, oyster farmers have been developing estuary‐wide environmental management systems ( EMSs ) to tackle internal (i.e. industry‐related) and external (i.e. catchment) issues in N ew S outh W ales, A ustralia. Drawing on interview‐based research and document analyses, this paper shows that the process of creating an EMS for the oyster industry, as well as the creation of the EMS itself, resulted in legitimizing the industry's stewardship over the natural resource it depends on (water). For the oyster industry, this result was due to a change in the scale on which EMSs have been developed: instead of viewing issues at the individual business level, the systems expanded their viewpoint to the entire catchment, and included every oyster business in the estuary, as well as all other activities in the upper catchment. By providing a means of communicating internal efforts and with the support of local government bodies, EMSs provided a mechanism with which influence over upstream actors and activities could be exerted. We demonstrate this by using the ‘social‐ecological systems’ and ‘ ENCORE ’ frameworks, emphasizing the transitions that allowed for this change of scale to take place.  相似文献   
363.
This paper presents a new methodology for impact assessment—SIAM (Spatial Impact Assessment Methodology)—which is based on the assumption that the importance of environmental impacts is dependent, among other things, on the spatial distribution of the effects and of the affected environment. The information generated by the use of Geographical Information Systems (GIS) in impact identification and prediction stages of Environmental Impact Assessment (EIA) is used in the assessment of impact significance by the computation of a set of impact indices. For each environmental component (e.g., air pollution, water resources, biological resources), impact indices are calculated based on the spatial distribution of impacts. A case study of impact evaluation of a proposed highway in Central Portugal illustrates the application of the methodology and shows its capabilities to be adapted to the particular characteristics of a given EIA problem.  相似文献   
364.
We integrate information from several disparate data sources including agricultural statistics and remote sensing to quantify and map the distribution and dynamics of agricultural returns to land and water resources from 1996/1997 to 2000/2001 in the Murray–Darling Basin (MDB), Australia. Total profit to agriculture was estimated at AUD3.86B in 1996/1997 and AUD3.73B in 2000/2001. The mapping reveals a high spatial concentration of economic returns to land and water resources from agriculture. Dryland agriculture covers over 82% of the study area. Irrigated agriculture covers 1.7% of the land area (2000/2001) but returns one third of the total profit to agriculture. We found that around 80% of the profit to agriculture comes from just over 5% of the land area. The results from this regional scale economic mapping can inform regulatory policy and public investments in natural resource management through targeting industries and regions that provide low marginal returns to the natural resource base.  相似文献   
365.
采用人口重心模型,在GIS技术支持下着重对1989-2005年山东省人口重心迁移特征进行了研究,并在此基础上分析人口重心迁移的主要影响因素。结果显示,山东省人口重心接近几何中心,人口重心自东北向西南方向迁移的趋势明显,其移动轨迹呈现出一定的曲折和波动。山东省人口重心迁移受自然、社会经济和政策等多种因素的影响。  相似文献   
366.
以江苏省环境监测人员上岗理论考试工作流程为基础,介绍了上岗证机考系统的设计思路及开发背景,并对系统开发过程中遇到的问题进行了剖析,对系统的二次开发和功能扩展进行了设想,目的在于使该机考系统功能更加完善、适用和通用。  相似文献   
367.
多源环境监测信息交换模型的设计与实现   总被引:2,自引:0,他引:2  
针对环境监测系统现有的污染源管理、饮用水管理、噪声管理、自动监测管理等信息系统存在异构化、多源化等现象,造成数据重复录入、数据不一致、资源浪费等问题,展示了一种数据交换模型的设计思路和实现方法,介绍模型的数据抽取、数据封装、数据传递、数据解析、数据映射、校验和转换、数据接收等多个环节。该数据交换模型已成功实现与多个外部业务系统数据对接,现每天采集的数据超过5 000条,系统运行稳定、性能良好。  相似文献   
368.
排污许可证实施的监督管理探析   总被引:1,自引:0,他引:1  
按照机制设计理论,提出了排污许可证实施监督管理的发展阶段,以及政府在不同阶段的关键作用。基于排污许可证行政许可的属性,归纳了不同层级政府监督管理的框架和内容,包括监督性监测、许可证执行监督和守法系统监控。从公众参与、政府和企业信息公开两个角度,总结了排污许可证实施的社会监督管理内容。  相似文献   
369.
The offshore oil industry has expanded to deep water and Arctic. The harsh operating conditions (e.g., ice and strong wind) and increasing complicated system raise the occurrence likelihood of system faults. This requires timely fault isolation and management in the subsea system. However, the offshore oil industry mainly relies on humans to isolate faults based on alarms. With harsh operating conditions and increasing complicated system, this industry urgently needs research on more efficient fault isolation and cause diagnosis methods. Unfortunately, limited research is conducted on fault isolation method in the offshore oil industry. Furthermore, in industry 4.0 era, large amounts of information are obtained. This provides precondition for the application of information fusion technique which aims to improve diagnosis results. However, to the authors’ knowledge, information fusion has not been much studied in the fault isolation of the offshore oil industry. Moreover, the interaction of different subsystems contains valuable information. How the interaction of different subsystems can influence the fault diagnosis has not been explored. This paper proposes a Bayesian network (BN) based method for timely fault isolation and cause diagnosis for the offshore oil industry. The work fuses different information, and it also includes the dependency among different subsystems in the fault diagnosis. As an important alarm source, false alarms are also taken into account in the model. A case study on the subject of the subsea wellhead and chemical injection systems is conducted to demonstrate the functions and merits of the proposed method.  相似文献   
370.
薛璐 《环境与发展》2020,(1):153-153,155
随着新时代的全面到来,我国对于生态环境的重视程度也在不断提高,社会民众的环保意识也变得越来越高。在这种大背景下,环境监测科技得到了全面的发展,同时在我国各个地区也开始广泛的应用。本文先阐述了新形势下环境监测科技的发展现状,从信息化技术的深层次应用、形成多元化与多层次的监测技术格局、构成创新化的环境监测技术体系、逐步实现监测人员专业素质水平的提升四个方面,综合全面探讨了新形势下环境监测科技的发展与展望。  相似文献   
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