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991.
992.
针对当前数字区域工程建设普遍存在的一些问题,提出“数字区域”应用基础设施的概念,对其研究背景、参考模型和面向信息共享的公共应用服务平台进行了论述。数字区域应用基础设施是在区域网络基础设施和数据基础设施上层的基础设施,它为电子政务、电子商务、数字城市等各种数字区域信息化应用工程提供基础性的应用服务支撑,由专业信息服务机构、管理办法、标准规范、关键技术和公共应用服务平台构成。信息服务机构是数字区域应用基础设施的主体,是有效联系信息需求方和信息拥有方的桥梁;公共应用服务平台是数字区域应用基础设施的核心,为区域信息共享和交换提供了统一的构架和解决方案。其中,元数据管理和目录服务平台为信息的发布和查询提供了“一站式”入口;信息共享与协作服务平台实现了分布式数据库的信息共享和交换;地理空间信息网络服务平台实现了地理空间信息的集中式共享。最后,总结了“数字福建”应用基础设施建设的成果,对“十一五”“数字福建”工程的需求和发展作了展望。 相似文献
993.
王昌洪 《测绘与空间地理信息》2011,34(1):89-91
测量监理信息管理系统是工程测量监理现代化的趋势。在分析目前工程测量监理实际的基础上,提出了系统设计思想、软硬件开发环境、系统功能的设计方法。该系统的设计与实现将对工程测量监理的质量、工期、投资控制等起到一定的促进作用。 相似文献
994.
995.
Spatial dimensions of New Zealand's environmental management 总被引:1,自引:0,他引:1
New Zealand's regional council boundaries drawn as part of the 1989 local government reforms privilege integrated catchment management. This privilege is now challenged by calls to both fragment and amalgamate councils and centralise decision‐making but with little analytic assessment of the spatial differentiation to support them. The spatial underpinnings of these calls were explored using a case study that assessed the spatial dimensions of environment management. Analysis of the Land Environments and River Environment Classification databases and councils' planning documents highlights challenges local governments face in applying integrated natural resource management within single purpose jurisdictions and implications for wider sustainable development policy. 相似文献
996.
AbstractTo enable assessment of risks of water management to riparian ecosystems at a regional scale, we developed a quantile-regression model of abundance of broadleaf cottonwoods (Populus deltoides and P. fremontii) as a function of flood flow attenuation. To test whether this model was transferrable to narrowleaf cottonwood (Populus angustifolia), we measured narrowleaf abundance along 39 river reaches in northwestern Colorado, USA. The model performed well for narrowleaf in all 32 reaches where reservoir storage was <75% of mean annual flow. Field data did not fit the model at four of seven reaches where reservoir storage was >90% of mean annual flow. In these four reaches, narrowleaf was abundant despite peak flow attenuation of 45–61%. Poor model performance in these four reaches may be explained in part by a pulse of narrowleaf cottonwood expansion as a response to channel narrowing and in part by differences between narrowleaf and broadleaf cottonwood response to floods and drought.
Editor Z.W. Kundzewicz; Guest editor M. AcremanCitation Wilding, T.K., Sanderson, J.S., Merritt, D.M., Rood, S.B., and Poff, N.L., 2014. Riparian responses to reduced flood flows: comparing and contrasting narrowleaf and broadleaf cottonwoods. Hydrological Sciences Journal, 59 (3–4), 605–617. 相似文献
997.
潍坊市坚持以科学发展观为指导,不断加强矿产资源执法监管力度,严格治理整顿矿产资源开发秩序,强化地质勘查和保护治理,科学调整矿业结构,优化开发布局,全面提高矿产资源综合利用水平,取得了较好的社会效益、经济效益和生态效益。 相似文献
998.
999.
The solute and suspended‐sediment load following five rainstorms (2005–2007) with varied intensities were studied at the Vernegà experimental watershed, north‐western Spain. Two land‐use areas are located within this watershed, the upstream one (forest) with 160 ha a 100% forested area, and the downstream one (agricultural) with 97 ha being 9 ha conventional agricultural field and 88 ha forest. This study investigates the capacity of each land‐use to yield water, suspended sediment concentration (SSC) and dissolved solid concentration (DSC). The hypothesis is that DSC and SSC from the agricultural area are greater than DSC and SSC of the forest area. Results showed that the agriculture area produced significantly greater mean DSC than in the forest area, the main contribution was the Ca2+ (24·68 ± 46·52 mg l?1) ion at the agricultural area. A long‐term sediment production rate at the agricultural outlet was calculated (69·1 tonnes per 100 years) based on the total sediment discharge (TSD) and the recurrence interval of the largest event of the five rainstorms (October 2005). Geographic information system (GIS) spatial data layers of the watershed were produced to determine the relation of tracks, landforms, slopes and forest management to SSC yield in the forest outlet (133·89 ± 308·14 mg l?1) during the five rainstorms. Agriculture practices are the main cause of soil erosion at the study area. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
1000.
随着我国社会的发展和经济体制改革的不断深入,农村土地流转的方式越来越多,范围越来越广。如何在保障农户土地承包经营权的前提下,推进土地承包经营权有序流转,提高农业产业化水平是深化农村改革的一个现实课题和长远目标。该文以宋村镇农村土地承包经营权流转的调查数据为例,分析了土地流转的现状和特点,指出当前存在的矛盾和问题,提出了农村土地流转机制的对策和建议。 相似文献