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201.
Elevated turbidity (Tn) and suspended sediment concentrations (SSC) during and following flood events can degrade water supply quality and aquatic ecosystem integrity. Streams draining glacially conditioned mountainous terrain, such as those in the Catskill Mountains of New York State, are particularly susceptible to high levels of Tn and SSC sourced from erosional contact with glacial-related sediment. This study forwards a novel approach to evaluate the effectiveness of stream restoration best management practices (BMPs) meant to reduce stream Tn and SSC, and demonstrates the approach within the Stony Clove sub-basin of the Catskills, a water supply source for New York City. The proposed approach is designed to isolate BMP effects from natural trends in Tn and SSC caused by trends in discharge and shifts in average Tn or SSC per unit discharge (Q) following large flood events. We develop Dynamic Linear Models (DLMs) to quantify how Tn-Q and SSC-Q relationships change over time at monitoring stations upstream and downstream of BMPs within the Stony Clove and in three other sub-basins without BMPs, providing observational evidence of BMP effectiveness. A process-based model, the River Erosion Model, is then developed to simulate natural, hydrology-driven SSC-Q dynamics in the Stony Clove sub-basin (absent of BMP effects). We use DLMs to compare the modelled and observed SSC-Q dynamics and isolate the influence of the BMPs. Results suggest that observed reductions in SSC and Tn in the Stony Clove sub-basin have been driven by a combination of declining streamflow and the installed BMPs, confirming the utility of the BMPs for the monitored hydrologic conditions. 相似文献
202.
Secure property rights are widely understood as critical for socio-economic development and sustainable land management in forested areas. Policies and programs, ranging from devolution of specific resource rights to formal land titling, have therefore been implemented to strengthen forest tenure and property rights in countries around the world. Despite the prevalence and importance of these efforts, however, systematic understanding of their effects on poverty remains lacking. We address this gap by systematically reviewing evidence on the impact of forest property rights interventions on poverty worldwide. We drew from a systematic map of evidence on forest-poverty links (Cheng et al., 2019) and used a population-intervention-comparator-outcome (PICO) framework to identify relevant studies. Our final dataset included 61 articles published from 2002 to 2016 comprising 91 case studies across 24 countries. Of these, only 11 articles (22 cases) used quasi-experimental methods to control for confounders. We find that almost all studied interventions (n = 88; 97%) focused on rights to access a forest area or withdraw resources from it. Relatively few studied interventions supported the more extensive property rights of exclusion (32%) and alienation (10%). Overall, reported impacts on both income/consumption and capital/assets dimensions of poverty were generally positive or mixed. Results from more robust quasi-experimental assessments showed greater variation, with case studies as likely to report negative as positive impacts on both poverty dimensions. We find tentative support for the economic theory that more secure property rights yield positive welfare effects. However, the paucity of evidence from more robust impact assessments constrains our ability to draw generalizable conclusions about the poverty impacts of different kinds of forest property rights interventions. 相似文献
203.
面对竞争相当激烈的测绘市场,从传统的人事管理向人力资源管理转变,是顺应社会发展的必然趋势。利用先进成熟的计算机、网络、数据库及通信等技术建立一个"准确、及时、标准、高效、安全"的人力资源管理系统,是实现测绘事业单位人力资源优化和管理信息化的重要途径,有效地提高了人力资源管理人员的工作效率。 相似文献
204.
就高校测绘实验室信息化管理平台的构建进行浅析与探讨,主要针对测绘实验室所承担的工作内容,并结合实际问题进行阐述。从实验室管理员的角度,结合教师、学生、企业三方面考虑,构建高校测绘实验室信息化管理平台不仅可以提高实验教学质量,而且还能实现实验室资源的优化配置。 相似文献
205.
翟艳青 《测绘与空间地理信息》2016,(4):37-40
进入新世纪以来,随着计算机技术、信息技术等新技术的发展,测绘技术装备也得到迅速发展,现代测绘技术装备在自动化、高效化方面的能力越来越突出,获取的数据类型也更加多样化。利用现代测绘技术装备服务于国土资源管理已经是大势所趋。本文结合现代测绘技术装备在国土资源管理中的应用范例,给出了相应建议,旨在提高现代测绘技术装备的应用能力,为国土资源管理提供全方位的服务。 相似文献
206.
针对我国机场噪声预测工作中存在的问题,根据地理信息系统的固有优势,采用面向对象的编程技术,开发建立基于GIS的机场噪声预测管理系统。按照自下而上的设计思路,将系统分为数据层、业务层和用户层三级结构,并且构建模块化操作,将系统分为GIS操作、噪声预测和信息管理三个模块,通过方便快捷的界面操作,实现了机场噪声预测和影响范围的查询和分析。实验结果表明,该系统能有效提高机场噪声预测和管理工作的效率和质量,为机场规划和航班制定提供及时、准确的决策参考。 相似文献
207.
何海康 《测绘与空间地理信息》2016,(8)
土地是人类赖以生存和发展的物质基础。真实、准确的土地所有权数据是国家进行宏观经济调控的基础和重要依据。本文以广东省韶关市某村为试点,介绍了农村土地承包经营权确权登记的技术路线和工作流程,探讨了权属调查及数据库建设的方法。 相似文献
208.
地理信息系统是把各种信息用地理以及相关的视图相结合,利用计算机及数据库技术对所需的信息进行收集和分析,经过分析和研究处理过的信息具有很高的使用价值,能够为土地利用、城市规划等各种大型工程提供数据参考。本文在简要阐述地理信息系统中测量数据管理问题的基础上,对新时期地理信息系统中测量数据管理的方式和优缺点及无缝空间数据管理的技术原理和优缺点进行了详细研究和分析。 相似文献
209.
测量标志巡查是加强测量标志管护的重要手段。本文采用网格化理念设计,集成应用网络、智能移动终端、工作流、地图网络化服务等技术提出了一种测量标志巡查信息直报技术,可实现全省测量标志巡查信息的采集、实时在线或事后离线(WIFI等)巡查信息报送、审核、入库、应用等业务的网络化、准实时化、一体化,提高了测量标志巡查工作的科学化和规范化。 相似文献
210.
Climate change impacts increase pressure on challenges to sustainability and the developmental needs of cities. Conventional, “hard” adaptation measures are often associated with high costs, inflexibility and conflicting interests related to the dense urban fabric, and ecosystem-based adaptation (EbA) has emerged as a potentially cost-efficient, comprehensive, and multifunctional approach. This paper reviews and systematises research on urban EbA. We propose an analytical framework that draws on theory from ecosystem services, climate change adaptation and sustainability science. It conceptualises EbA in terms of five linked components: ecological structures, ecological functions, adaptation benefits, valuation, and ecosystem management practices.Our review identified 110 articles, reporting on 112 cities, and analysed them using both quantitative statistical and qualitative content analysis. We found that EbA research in an urban context is fragmented due to different disciplinary approaches and concepts. Most articles focus on heat or flooding, and the most studied ecological structures for reducing the risk of such hazards are green space, wetlands, trees and parks. EbA is usually evaluated in bio-geophysical terms and the use of economic or social valuations are rare. While most articles do not mention specific practices for managing ecological structures, those that do imply that urban EbA strategies are increasingly being integrated into institutional structures. Few articles considered issues of equity or stakeholder participation in EbA.We identified the following challenges for future EbA research. First, while the large amount of data generated by isolated case studies contributes to systems knowledge, there is a lack of systems perspectives that position EbA in relation to the wider socio-economic and bio-geophysical context. Second, normative and ethical aspects of EbA require more thought, such as who are the winners and losers, especially in relation to processes that put people at risk from climate-related hazards. Third, there is room for more forward-looking EbA research, including consideration of future scenarios, experimentation in the creation of new ecological structures and the role of EbA in transformative adaptation. 相似文献