基于ArcGIS Server ADF的流域水环境专题图研究

专题地图是流域水环境信息的良好表达形式和信息载体,文章运用地理信息系统二次开发软件-ArcGIS Server ADF研究并实现水环境专题图展示功能。通过流域水环境信息专题地图可以表达水环境监测评价结果,能将水环境质量的空间规律直观显示,实现水环境质量评价信息的可视化,并表示其动态变化和发展趋势,揭示发展规律,以供有关专家、决策者获取各类重要信息,进行环保政策的研究分析和决策。     

基于C#与Surfer Automation完成大气污染扩散等值线自动化生成

等值线图绘制是大气扩散研究工作中的一项重要内容。基于C#编程技术,通过Surfer Active X Automation接口技术,在程序中实现了对Surfer等值线图绘制各方法和属性的调用,完成了等值线图的程序化批量绘制,并应用此技术实现了大气污染扩散的动态演示。该技术的运用使得大批量规格化绘制等值线图、向量图等变得简单易行,有助于提高研究人员的工作效率。     

广州市道路交通噪声地图的绘制

基于速度-密度关系模型,由浮动车速推算出广州市路网的交通流量,并从地理信息系统(GIS)加载道路及建筑物的属性信息作为噪声计算的输入参数;然后结合单车辆噪声排放模型及噪声传播扩散的基本原理,考虑城市建筑物群对交通噪声的遮挡衰减,建立了城市尺度的交通噪声计算模型,计算出了广州市的交通噪声值,并绘制出了广州市的交通噪声地图,结果可为广州市交通噪声污染的控制提供科学参考依据。     

基于大比例尺地形图的抗震规划工作底图缩编研究

工作底图的编制是开展抗震规划的基础工作之一,好的工作底图不仅能突出抗震规划专题信息,更有利于规划成果的应用。本文以1∶5 000地形图缩编成1∶5万抗震规划工作底图为例,分析了规划底图缩编过程中存在的问题,探索了基于AutoCAD、南方Cass软件以及Arcgis的缩编方法,从而有效提高抗震规划的工作效率。     

海洋生态系统健康评价软件的研制与应用

基于我国近海海洋综合调查与评价专项课题构建的生态系统健康评价指标体系和评价模式,应用数据库技术及面向对象的信息系统开发技术,研制了海洋生态系统健康评价软件,实现了评价过程的信息化、规范化、科学化。根据908专项调查数据,用该软件评价了我国近岸海域、近海海域及重点海域生态系统健康状况,制作了评价专题图,为海洋生态管理及决策支持提供重要的依据。     

The road map for green development of Western China

China has made some remarkable achievements in sustainable development,but the constant deterioration of the overall trend of the environment has not yet been effectively curbed.To achieve the goal of sustainable development,we must first ensure coordination and coherence of national development goals in different areas and adhere to green development road.To achieve the objectives related to green development,and to clarify the direction of green development in the next 20years,a road map is needed to guide and coordinate the process.This paper describes the concept of the green development road map,introduces a green development road map for the western region,and further elaborates it The road map clarifies the objectives and guiding principles of green development in the western region,points the areas that deserve more concern and institutional innovation,and builds a green development monitoring and evaluation(M&E)framework.Finally,the paper provides corresponding policy recommendations based on the established road map.     

关于全国推广洪水风险图的认识与设想

近年来，随着我国社会经济的加速发展，水灾损失也在急剧增长。洪水风险区域内人口资产密度提高，而经济发展中缺乏水患意识，减灾措施不足，以及总体上防洪保护标准偏低等，是水灾损失剧增的重要原因。为了扭转被动局面，国家防汛抗旱总指挥部决定在全国推广洪水风险图。世界各国防洪形势国情不同，洪水风险图的绘制目的与风险图的内容和表达形式也有显著差异。本文通过基本国情的分析和中外风险图绘制目的与必备内容的比较，探讨适合于我国推广的洪水风险图形式。     

Bayesian model-based cluster analysis for predicting macrofaunal communities

To predict macrofaunal community composition from environmental data a two-step approach is often followed: (1) the water samples are clustered into groups on the basis of the macrofauna data and (2) the groups are related to the environmental data, e.g. by discriminant analysis. For the cluster analysis in step 1 many hard, seemingly arbitrary choices have to be made that nevertheless influence the solution (similarity measure, clustering strategy, number of clusters). The stability of the solution is often of concern, e.g. in clustering by the program. In the discriminant analysis of step 2 it can occur that a water sample is misclassified on the basis of the environmental data but on further inspection happens to be a borderline case in the cluster analysis. One would then rather reclassify such a sample and iterate the two steps. Bayesian latent class analysis is a flexible, extendable model-based cluster analysis approach that recently has gained popularity in the statistical literature and that has the potential to address these problems. It allows the macrofauna and environmental data to be modelled and analyzed in a single integrated analysis. An exciting extension is to incorporate in the analysis prior information on the habitat preferences of the macrofauna taxa such as is available in lists of indicator values. The output of the analysis is not a hard assignment of water samples to clusters but a probabilistic (fuzzy) assignment. The number of clusters is determined on the basis of the Bayes factor. A standard feature of the Bayesian method is to make predictions and to assess their uncertainty. We applied this approach to a data set consisting of 70 water samples, 484 macrofauna taxa and four environmental variables for which previously a five cluster solution had been proposed. The standard for Bayesian estimation, the Gibbs sampler, worked fine on a subset with only 12 selected taxa but did not converge on the full set with 484 taxa. This is due to many configurations in which the assignment probabilities are all very close to either 0 or 1. This convergence problem is comparable with the local optima problem in classical cluster optimization algorithms, including the EM algorithm used in Latent Gold, a Windows program for latent class analysis. The convergence problem needs to be solved before the benefits of Bayesian latent class analysis can come to fruition in this application. We discuss possible solutions.     

A phenomenological model without dispersal kernel to model species migration

Phenomenological approaches to model species migration are usually based on kernel-based methods. These methods require a good knowledge of the dispersal agent behaviour for a given species. They also calculate the location of individuals independently to each other (except the mother plant) and then suppress some of them according to additional interactions such as competition, facilitation and recruitment. In this paper, we propose to use a new phenomenological method, the Gibbs method, to model tree species migration at large scale. The Gibbs method handles the location of adult individuals in terms of pairwise interactions described by a potential function. This function summarizes the set of known and unknown factors determining the spatial distribution of the individuals (or cohorts). The principle of the Gibbs method is to minimize the sum of all pairwise interactions, also called the cost function, in order to optimize the spatial point pattern according to the chosen potential function.