基于SCS-CN与GIS耦合模型的闽三角城市群承灾空间淹没风险研究

以闽三角城市群为研究对象,创新水文SCS-CN算法与GIS耦合技术,计算出不同暴雨重现期(5 a,10 a,50 a一遇)下的淹没范围,构建闽三角城市群内涝淹没风险评估体系.通过地理探测器进一步探究淹没风险与社会生态系统空间分布规律,为闽三角城镇群的生态安全保障与可持续发展提供技术支撑.研究表明:闽三角城市群内涝淹没区...     

城市景观格局与大气颗粒物污染的关系研究

随着城市化和工业化发展,大气颗粒物对城市空气环境造成了严重污染,选取西安市作为研究区,分析不同时间和空间尺度下城市景观格局与大气颗粒物污染的关系。通过GIS软件、Fragstats4.2软件和SPSS软件对西安市2014年土地利用数据和2014年整年的大气颗粒物监测数据进行分析,结果显示,西安市土地利用类型分布较为集中;西安市大气颗粒物浓度的空间分布特征为浓度从市中心至城郊呈梯度递减趋势,在整体上呈现西北高于东南的倾向,大气颗粒物污染物浓度峰值基本都集中出现在建设用地范围内(PM10:102.7μg/m^3;PM2.5:99.7μg/m^3);相关性结果证实了城市景观格局与大气颗粒物浓度的空间分布特征。研究结果为中国西部内陆城市大气颗粒物污染控制、土地利用规划以及生态建设提供参考。     

基于GIS的污染源自动监测数据综合分析系统设计和实现

基于地理信息系统(GIS),将污染源在线监测数据信息与空间地理信息相结合,建立北京市重点锅炉烟气、污水处理厂两类主要污染源和水环境质量等大量在线监测数据的监控和综合分析系统。系统不仅实现了对重点污染源在线监测数据的实时监控、数据展示、统计分析、超标报警等常规业务功能,还在污染源扩散模拟展示、污染源与环境质量信息相互作用的空间综合分析等方面进行了初步研究,为进一步提高北京市的污染源监控管理和自动监测数据利用水平做出了创新性的技术尝试。     

基于AGNES算法优化BP神经网络和GIS系统的大气污染物浓度预测

建立了大气污染物浓度与影响因子之间的BP神经网络,对城市中各监测点位的次日大气污染物浓度进行预测,采用GIS的插值分析进行污染物空间分布预测,其中BP神经网络的输入向量采用AGNES算法进行处理。以太原市区SO2、PM10浓度预测为例,选择气温、湿度、降水量、大气压强、风速和前5天的污染物浓度等10个参数训练BP神经网络,结果表明,BP神经网络的训练效果较好,预测结果与实际浓度显著相关,R2分别为0.988、0.976;结合太原市8个监测点位的污染物浓度预测值,运用GIS空间差值法绘出SO2、PM10的浓度分布预测图,该图与实际情况大体符合,并且与国控大气污染企业的分布显著相关,Pearson相关系数分别为0.969、0.949。     

基于GIS的城市SEE信息查询系统研究

基于数字城市的理念,将信息技术和社会经济环境(SEE)问题结合起来,将GIS与网络技术相结合,基于GIS空间分析功能中的空间查询和量算功能,提出了城市SEE信息查询系统的框架,实现了城市生态环境及可持续发展基础信息的整理。     

Watershed-based riverine discharge loads and emission factor of perfluorinated surfactants in Korean peninsula

Long-range transport of and exposure to perfluorinated substances (PFSs) strongly depend on their emission mode. In the present study, watershed-based riverine discharge loads and emission factors are estimated for perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorohexylsulfonate (PFHxS), and perfluorooctylsulfonate (PFOS) by using spatially distributed data of chemical concentrations together with water flows and a geographic information system (GIS). Average per capita emissions (emission factor, μg capita⁻¹ d⁻¹) are 75 for PFOA, 36 for PFNA, 17 for PFHxS, and 43 for PFOS, which are several times lower than the estimates for Japan and the European continent. A relatively uniform distribution is observed for PFHxS and PFOS emission factors, while elevated values of PFOA and PFNA predominate in one of eight river basins. This may indicate the leading contribution of diffusive sources (e.g. nonpoint source) for PFHxS and PFOS versus the presence of localized point sources for PFOA and PFNA. The lower-upper bound of total riverine loads discharged annually from the Korean peninsula are in the range of 0.53-1.3 tons for PFOA, 0.09-0.60 tons for PFNA, 0.07-0.29 tons for PFHxS, and 0.19-0.73 tons for PFOS, accounting for <1% of global annual emissions. Furthermore, these riverine discharge loads are significantly greater than the discharge loads from a wastewater treatment plant, indicating the necessity of further study of nonpoint sources.     

Identifying Urban Features from LiDAR for a High‐Resolution Urban Hydrologic Model

Light Detection and Ranging (LiDAR), is relatively inexpensive, provides high spatial resolution sampling at great accuracy, and can be used to generate surface terrain and land cover datasets for urban areas. These datasets are used to develop high‐resolution hydrologic models necessary to resolve complex drainage networks in urban areas. This work develops a five‐step algorithm to generate indicator fields for tree canopies, buildings, and artificial structures using Geographic Resources Analysis Support System (GRASS‐GIS), and a common computing language, Matrix Laboratory. The 54 km² study area in Parker, Colorado consists of twenty‐four 1,500 × 1,500 m LiDAR subsets at 1 m resolution with varying degrees of urbanization. The algorithm correctly identifies 96% of the artificial structures within the study area; however, application success is dependent upon urban extent. Urban land use fractions below 0.2 experienced an increase in falsely identified building locations. ParFlow, a three‐dimensional, grid‐based hydrological model, uses these building and artificial structure indicator fields and digital elevation model for a hydrologic simulation. The simulation successfully develops the complex drainage network and simulates overland flow on the impervious surfaces (i.e., along the gutters and off rooftops) made possible through this spatial analysis process.     

Exploring the determinants for adopting water conservation measures. What is the tendency of landowners when the resource is already at risk?

In Finland, the current water conservation policy sets equal incentives for water conservation, regardless of the environmental condition. Before any policy reform, it is vital to investigate the tendency of landowners to adopt water conservation measures. In this study, we were interested in examining adoption if the soil quality implies a high leaching risk and if the water quality is already poor. By combining survey data with GIS data, we analysed the effect of farm and farmer characteristics and attitudes towards adoption. Our probit models indicated that financial variables were the key determinants of adoption for active farmers, whereas for passive owners, adoption was also explained by attitudes. In contrast to our expectations, adoption in areas under risk was weakly supported by our estimates. Environmental awareness, providing it increases with risk, is not strong enough to motivate adoption. Targeted agri-environmental measures, even though costly, cannot be avoided, and spatially tailored measures can attract adopters in hotspot areas.     

区域地表水监测断面优化调整的技术方法

对中国地表水水质监测断面布设的现状及问题进行分析,简要回顾了中国地表水监测断面设置及优化的研究进展,论述了区域地表水点位优化的目的和原则,提出从宏观、中观、微观3个层次的对区域地表水监测断面进行调整的步骤和方法,并阐述了地理信息系统技术在监测断面优化中的作用。     

基于遥感数据的生态脆弱区森林景观分类及格局研究——以香格里拉为例

以Landsat-7 ETM＋为数据源，在遥感（RS）和地理信息系统（GIS）技术的支持下，对云南省香格里拉县北部进行森林景观分类及其景观结构分析。结果表明，研究区以针叶林为主要森林景观，阔叶混交林的形状结构较为松散，景观破碎化程度最严重，人为干扰强烈。因此，需加强森林保护，减少人为干扰，防止景观破碎化程度的进一步加深。