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501.
Hossein Zeinivand 《国际地球制图》2017,32(4):386-400
This paper examines the effects of watershed complexity in terms of physiography and land use on the specific sediment yield of the Chardavol watershed (1012.946 km2) in Iran. First, specific sediment yield was simulated using spatially distributed hydrological WetSpa model, then the influential factors such as morphometric variables, land-use composition and pattern and soil properties of the watershed were calculated at the sub-watershed scale. Due to the inter-reliant of these watershed characteristics, a partial least squares regression (PLSR) was used to illustrate the relationship between the specific sediment yield and data of 15 selected watershed characteristics. The results showed that the land-use composition and soil properties had the maximum effects on the specific sediment yield and clarified 79% of the variation in the specific sediment yield. Regarding the availability of digital spatial database over the watershed, this simple PLSR procedure could be applied in different watersheds. 相似文献
502.
城市规划不仅是城市管理与决策的重要手段,同时也是企业发展的指向标。如何高效、快速地浏览和查询信息,以及确保信息的权威性是规划的关键。本文基于Android平台并结合地理信息技术,开发了基于Android的城市规划浏览和查询系统。系统提供地图基础操作功能、规划展示功能和查询功能,为用户提供直观有效的规划和查询,发挥3S技术在城市管理中的作用,加快城市由传统管理到智能移动管理的进程。 相似文献
503.
2015年6月,全国已完成地理国情普查数据的采集、处理与底图制作等工作。本文基于地理国情普查数据,探讨利用普查数据成果完成空间规划底图的快速智能编制工作,基于研究成果完成空间规划底图智能编制处理系统的设计与开发,为空间规划底图编制的快速化、智能化需求提供一种新的解决思路。 相似文献
504.
This paper presents a set of energy and resource intensive scenarios based on the concept of Shared Socio-Economic Pathways (SSPs). The scenario family is characterized by rapid and fossil-fueled development with high socio-economic challenges to mitigation and low socio-economic challenges to adaptation (SSP5). A special focus is placed on the SSP5 marker scenario developed by the REMIND-MAgPIE integrated assessment modeling framework. The SSP5 baseline scenarios exhibit very high levels of fossil fuel use, up to a doubling of global food demand, and up to a tripling of energy demand and greenhouse gas emissions over the course of the century, marking the upper end of the scenario literature in several dimensions. These scenarios are currently the only SSP scenarios that result in a radiative forcing pathway as high as the highest Representative Concentration Pathway (RCP8.5). This paper further investigates the direct impact of mitigation policies on the SSP5 energy, land and emissions dynamics confirming high socio-economic challenges to mitigation in SSP5. Nonetheless, mitigation policies reaching climate forcing levels as low as in the lowest Representative Concentration Pathway (RCP2.6) are accessible in SSP5. The SSP5 scenarios presented in this paper aim to provide useful reference points for future climate change, climate impact, adaption and mitigation analysis, and broader questions of sustainable development. 相似文献
505.
The transformation of tropical ecosystems by humans have resulted in forest loss, which, in turn, have caused negative impacts on biodiversity and the provisioning of ecosystem services. There is an urgent need to plan the restoration of these human-modified landscapes, using methodological approaches that consider key processes occurring at different spatial scales while engage local community participation, offering them the best possibilities of tangible benefits. In this study, was evaluated the landscape spatial pattern and local conservation status of existing forest remnants, showing an analysis of possible restoration scenarios for a human-modified landscape in La Montaña, an indigenous region in southwestern Mexico. Therefore, landscape and local scale approaches were linked to identify specific landscape elements where efforts to improve connectivity must be concentrated. Also, this approach allowed finding a set of species from reference sites that showed the best socioecological characteristics to be used in different restoration strategies. As expected, La Montaña region showed a spatial pattern typical of highly human-modified landscapes, i.e., several small (<21 ha) and irregular forest remnants with strong forest edge effects. Furthermore, these small and irregular forest fragments displayed forest structure, diversity and composition characteristics similar to those communities disturbed by selective harvesting or in an early successional phase. However, about 100 of woody species were found inside the fragments, some with important potential to provide ecosystem services. The landscape connectivity was very low, and an analysis of possible restoration scenarios showed that is equally important to restore the productive areas as well as open forest, to recover up to 47% of landscape connectivity. In this sense, it was proposed a productive restoration strategy to enrich open forests and create biodiversity-friendly habitat in agricultural areas, using species with high socioecological potential. We believe that the same approach could be applied to other highly human-modified tropical landscapes with similar socioecological problems. 相似文献
506.
It is essential to ensure equal accessibility to services, such as sport and recreation facilities or green and water environments. Differences in accessibility can potentially cause negative health and social welfare implications. Accessibility and service area analyses from the perspective of access equality are typically rather simple. They are often based on arbitrary travel-distance thresholds and made only with a single mode of transport in mind. Thus, they exclude the multidimensional nature of accessibility where individuals' travel behavior and perceived accessibility also play an important role. In this paper, a PPGIS method was used to empirically investigate distances and durations that respondents travel with different modes of transport to access popular water environments. Service area analyses were built on person-based and objectively measured threshold values that not only take into account the spatio-temporal elements of transport networks and a land use component but also recognize the requirements and preferences of individuals and their capacity to access and participate. The results showed that the most common mode of transport to access waters is walking. Generally, the residents travel by foot for 1.7 km to access water environments. Cars were found as the second most common mode of transport used, and most of the popular water environments are accessible by car from every corner of the study area in a given travel threshold time. The results demonstrate the importance of deriving local parameters and the potential of the PPGIS approach for accessibility and service area delineation. 相似文献
507.
Conventional ways of trip planning using online reviews from multiple sources are often cumbersome and uncustomizable. The advance in information and communication technology (ICT) and the surge in user-generated contents (UGC) provide great opportunities to facilitate trip planning. This paper proposes a travel-planning tool by crowdsourcing multiple UGCs to provide customized information for tourists. We harvested hotel customer reviews from TripAdvisor, photo information from Flickr, and travel costs between destinations from Uber. First, we used geospatial data mining approaches to extract tourism attractions information from Flickr; identified multi-facet characteristics of hotels with natural language processing (NLP); and provided travel route recommendations with graph analysis. Second, we developed a web-based interface to let users communicate with the system interactively, which provides integrated recommendations including attractions, hotels, and visit route sequences. Two cities in the United States (i.e. Atlanta and Chicago) were used as cases to illustrate our approaches. The proposed travel planning tool is not only beneficial to support customized travel decision-making, but also supportive for hotel managers with strategic management implications. 相似文献
508.
针对现有城市地铁网络结构评价研究的不足,该文提出运用中心性评价方法分析地铁网络中站点的重要程度,实现对网络结构的评价:引入中心性方法的度中心性、介中心性和邻近中心性指标,提出一种基于客观权重赋权法的系统中心性评价指标,对地铁网络的中心性进行计算。以广州市为研究区域,分析了广州市地铁网络中心性空间分布和频率分布特征。结果表明,较现有线网,广州市地铁规划线网各项中心性指标分布更为均匀,市辖区间联系更为紧密。中心性评价指标能够对非采用单一票制的广州地铁系统的网络结构进行评价,为规划方案的制定提供参考。 相似文献
509.
针对滇西北民族地区资源的相似性和趋同性导致了身处滇西北旅游圈腹地的剑川县民俗文化资源闲置和浪费的问题,该文在分析剑川县民俗旅游资源现状的基础上,挖掘其民俗文化旅游资源,采用德尔菲法与模糊层次综合评价法对剑川县民俗文化资源进行定性与定量的综合评价,并借助GIS技术的空间分析功能对剑川县民俗旅游资源结构和空间分布格局进行较全面的分析,对剑川县民俗旅游资源进行评价、规划与开发,以改善民俗文化资源的闲置和浪费的现状,为县域旅游资源规划者和开发者提供借鉴。 相似文献
510.