我国副省级城市第三产业发展研究——以哈尔滨为例

第三产业发展水平是衡量一个国家经济实力的重要标准,综合评价第三产业,有助于正确认识我国各地区第三产业的发展水平。以我国15个副省级城市为研究对象,构建第三产业综合发展水平指标体系,运用主成分分析法,通过比较分析得出哈尔滨市第三产业发展中存在的问题,并提出相关对策建议。     

水利旅游吸引力评价模型与实证研究

水利旅游是水利经济的新兴增长点,吸引力评价是旅游开发的基础性研究。借鉴引力理论,构建了由25个指标组成的水利旅游吸引力评价指标体系,运用AHP—PCA—Borda主客观组合评价法,对我国水利旅游吸引力进行了实证评价。结果表明,水利旅游吸引力地区不平衡,江苏、广东、山东、湖北、河南、浙江、湖南、北京和江西等省水利旅游吸引力较强,西部省份和处于我国版图中轴线附近的省份水利旅游吸引力较弱。     

基于环境地理信息平台的预警系统的构建

随着经济的高速发展,环境污染事故也呈现出上升的势头,环境污染事故不仅造成了环境危害,而且对人民群众的安全产生了重大威胁。鉴于环境污染事故的多发性、危害性,应急处置显然非常重要,而构建强大的应急处置信息系统有助于应急处置和分析决策的顺利进行。本文分析了环境应急处置需求,提出了建立环境污染应急管理信息系统的设计框架。     

基于BP人工神经网络的城市PM2.5浓度空间预测

针对PM2.5日均质量浓度,采用BP人工神经网络模型,预测研究区空气中PM2.5浓度的空间变异,通过与普通克里格(Ordinary Kriging)插值方法对比验证BP人工神经网络预测模型的精度.结果表明:BP人工神经网络预测模型下研究区检验样本点位置的PM2.5仿真浓度与观测浓度之间的均方差、平均绝对误差、平均相对偏差和相关系数分别为0.296 μg2/m6、0.412 μg/m3、1.650％和0.851;而与此同时,普通克里格插值方法下的对应结果分别为1.041 μg2/m6、0.689 μg/m3、11.910％、0.638.研究成果在肯定BP人工神经网络预测模型可用于揭示PM2.5浓度空间变异特征的同时,也证实了其相对于普通克里格插值方法在固定空间点位准确预测PM2.5浓度方面的优势.     

基于GIS的南充市水资源综合管理系统设计

为了实现南充市水资源的高效利用,建设一个适用于现代信息网络化的水资源实时监控系统十分迫切,具有重要的现实意义和巨大的经济价值。本文对该系统设计体系结构、空间数据、各个系统功能作了说明。     

流域非点源分布式模型AnnAGNPS参数的不确定性研究

流域非点源分布式模型的不确定性研究成为目前的热点问题之一。本研究以宁波市章溪河流域为研究区,通过GIS软件AreView和AnnAGNPS模型,集成利用莫里斯分类筛选法,选取临界源面积、SCS曲线系数、水土保持因子、饱和导水率、氮磷吸收率、施肥量等6个因子进行敏感性分析。模拟结果表明,土壤饱和导水率、水土保持因子和径流曲线CN值对模型输出结果影响较大;水土保持因子对泥沙、总磷和总有机碳负荷的模拟结果影响最大,均呈显著负效应;径流曲线CN值对总氮负荷计算结果影响最大,呈显著正效应。     

Evaluation of the temporal variations of air quality in Taipei City, Taiwan, from 1994 to 2003

Data collected from the five air-quality monitoring stations established by the Taiwan Environmental Protection Administration in Taipei City from 1994 to 2003 are analyzed to assess the temporal variations of air quality. Principal component analysis (PCA) is adopted to convert the original measuring pollutants into fewer independent components through linear combinations while still retaining the majority of the variance of the original data set. Two principal components (PCs) are retained together explaining 82.73% of the total variance. PC1, which represents primary pollutants such as CO, NO(x), and SO(2), shows an obvious decrease over the last 10 years. PC2, which represents secondary pollutants such as ozone, displays a yearly increase over the time period when a reduction of primary pollutants is obvious. In order to track down the control measures put forth by the authorities, 47 days of high PM(10) concentrations caused by transboundary transport have been eliminated in analyzing the long-term trend of PM(10) in Taipei City. The temporal variations over the past 10 years show that the moderate peak in O(3) demonstrates a significant upward trend even when the local primary pollutants have been well under control. Monthly variations of PC scores demonstrate that primary pollution is significant from January to April, while ozone increases from April to August. The results of the yearly variations of PC scores show that PM(10) has gradually shifted from a strong correlation with PC1 during the early years to become more related to PC2 in recent years. This implies that after a reduction of primary pollutants, the proportion of secondary aerosols in PM(10) may increase. Thus, reducing the precursor concentrations of secondary aerosols will be an effective way to lower PM(10) concentrations.     

城市滨水景观评价研究初探——以南京市莫愁湖滨水区为例

城市滨水区一直被认为是一个城市最具活力和生态价值的区域,但伴随着城市职能的转型以及水运地位的下降,世界上大部分的滨水区都经历了从繁荣到衰败的过程。然而目前,随着城市人群的生态需求与审美需求的进一步提高,城市滨水区又面临着复兴之势,这也对城市滨水号观设计以及作为其基础而存在的滨水景观评价提出了新的要求。因此。本文将以成分代用模式评价方法为指导,以南京市莫愁湖滨水区为案例对其进行景观评价,并基于此获取影响滨水区景观质量的重要因素,以期对以后的滨水区规划设计起到一定的指导作用。     

Agricultural Chemicals in the Alluvial Aquifer of a Typical County of the Arkansas Delta

Statistical methods and a Geographic Information System (GIS) were used to investigate potential indicators of ground water vulnerability to agricultural chemical contamination in a representative area of the Mississippi River alluvial aquifer. A total of 47 wells were sampled for analysis of nitrate, phosphorus, potassium, and 13 pesticides commonly-used in the area. Ten soil and hydrogeologic variables and five ground water vulnerability indices were examined to explain the variations of chemical concentrations. The results showed that no individual soil or hydrogeologic variables or their linear combinations could explain more than 25% of the variation of the chemical concentrations. A quadratic response surface model with the values of confining unit thickness, slope, soil permeability, depth to ground water, and recharge rate accounted for 62% of the variation of nitrate, 43% of P, and 83% of K, suggesting that the interactions among soil and hydrogeologic variables were significant. Observed trends of decreasing nitrate and P concentrations with increasing well depth and/or depth to ground water seemed to correlate with carbonate equilibrium in the aquifer and more reduced environment with depth. In view of uncertainties involved, it was recognized that the limitations associated with input data resolution used in GIS and the formulation of leaching indices limited their use for predicting ground water vulnerability. Misuse of pesticides could be another factor that would complicate the relationships between pesticide concentrations and the vulnerability indices.     

上海地区农业气象灾害监测警示系统的研究

上海地区农业气象灾害监不系统是以实时气象数据为基础,根据农业气象灾害指标进行了评判分析,反映了农业气象灾害,接着,基于Activex的Web/GIS平台展示灾害的分布,并通过Internet网络,提供了多用户服务。