沈阳市环境监测信息网络的总体网络系统概况

采用环境信息网络与国内、省内及市内各重点污染源建立信息网络系统同时对环境质量进行监测。     

巯基纸富集——XRF测定水中Sb(Ⅲ)和Sb(Ⅴ)

在ｐＨ６．０的ＮＨ４ＡＣ－ＨＡＣ缓冲介质中，以巯基纸吸附和富集Ｓｂ（Ⅲ），吸附Ｓｂ（Ⅲ）后的巯基纸用Ｘ射线荧光测定；吸附Ｓｂ（Ⅲ）后的溶液于１ｍｏｌ／ＬＨｃｌ介质中，以巯基纸吸附Ｓｂ（Ⅴ），并按同样方法测定Ｓｂ（Ⅴ）。     

基于GIS的区域噪声信息管理系统

利用GIS技术建立区域噪声信息管理，能动态、直观地反映区域噪声的时空分布规律，为区域噪声控制研究提供强有力的工具。研究以MapInfo为主要的GIS开发工具，通过属性数据和空间数据的链接，实现了区域噪声分布的地图化表现、动态查询、基本空间分析等功能。利用该系统，可以对某市重点工业区区域噪声的空间分布规律进行GIS实例分析。     

网站信息的安全策略研究

网站是信息的发布中心 ,其数据库中存放着大量的供用户共享的重要信息 ,因此 ,网站信息安全是网站建设和运行过程中应该充分考虑和重视的问题。笔者从信息之源 (数据库 )、数据库运行环境 (操作系统 )以及信息发布平台 (Web服务器 ) 3个方面 ,论述了网站信息安全问题 ,并结合当前流行的实用系统 ,阐述了网站信息的安全策略     

基于专家地理信息系统(EGIS)的露天采矿烟尘污染环境效应评价模型

针对露天矿山烟尘污染源的特点 ,运用环境评价的原理和方法 ,探讨了传统评价工作中存在的不足 ,将地理信息系统 (GIS)应用到露天矿烟尘污染控制中 ,提出了基于专家地理信息系统 (EGIS)的烟尘污染环境效应评价模型 ,并评述了该模型的重要意义和发展前景     

GIS技术在自然保护区规划中的应用

通过对GIS技术在自然保护区规划中应用现状的综合分析,探讨了该技术目前的研究热点、发展趋势和存在的问题.目前该领域研究热点是GIS技术如何与遥感(RS)和全球定位系统(GPS)技术有机结合;如何有效处理大量观测调查数据中存在的不确定性是目前面临的主要问题之一;而GIS制图出图技术如何与图形处理软件Photoshop等有...     

排污权交易管理信息系统设计

本文为我国的排污权交易设计了一套管理信息系统。该系统设计采用C／S和B／S混合架构体系,充分发挥了两者的长处。该系统一方面可以同时为环境管理部门、排污企业和社会公众三类主体提供信息化服务,大大方便了排污权的交易过程,并保证了排污权交易的公平与透明;另一方面可以使环境管理人员方便地查询和检索相关企业,简化了环境管理工作。     

基于GIS的中秦岭地区滑坡灾害易发性研究

本文以中秦岭地区为滑坡易发性评价对象,针对研究区的情况,选取了坡度、起伏度、地貌类型、岩性、土壤侵蚀强度、活动断裂距、地震动参数、地下水类型、多年平均降雨量9个评价因子,建立了研究区滑坡易发性评价的数据库。运用单因子概率比率模型对各因子和滑坡的相关性进行了评价,揭示了该区滑坡灾害类型特点及空间分布规律,明确了中秦岭地区滑坡地质灾害的极高易发、高易发三大聚集地区的位置。     

Information processing in models for density-dependent emigration: A comparison

Density-dependent emigration has been recognized as a fitness enhancing strategy. Yet, especially in the modelling literature there is no consensus about how density-dependent emigration should quantitatively be incorporated into metapopulation models. In this paper we compare the performance of five different dispersal strategies (defined by the functional link between density and emigration probability). Four of these strategies are based on published functional relationships between local population density and emigration probability, one assumes density-independent dispersal. We use individual-based simulations of time-discrete metapopulation dynamics and conduct evolution experiments for a broad range of values for dispersal mortality and environmental stochasticity. For each set of these conditions we analyze the evolution of emigration rates in ‘monoculture experiments’ (with only one type of dispersal strategy used by all individuals in the metapopulation) as well as in selection experiments that allow a pair-wise comparison of the performance of each functional type. We find that a single-parameter ‘asymptotic threshold’ strategy - derived from the marginal value theorem - with a decelerating increase of emigration rate with increasing population density, out-competes any other strategy, i.e. density-independent emigration, a ‘linear threshold’ strategy and a flexible three-parameter strategy. Only when environmental conditions select for extremely high emigration probabilities (close to one), strategies may perform approximately equally. A simple threshold strategy derived for the case of continuous population growth performs even worse than the density-independent strategy. As the functional type of the dispersal function implemented in metapopulation models may severely affect predictions concerning the survival of populations, range expansion, or community changes we clearly recommend to carefully select adequate functions to model density-dependent dispersal.     

Evaluate HAA removal in biologically active carbon filters using the ICR database

The effects of biologically active carbon (BAC) filtration on haloacetic acid (HAA) levels in plant effluents and distribution systems were investigated using the United States Environmental Protection Agency’s Information Collection Rule (ICR) database. The results showed that average HAA5 concentrations in all locations were 20.4 μg·L^-1 and 29.6 μg·L^-1 in ICR plants with granular activated carbon (GAC) and ICR plants without GAC process, respectively. For plants without GAC, the highest HAA levels were observed in the quarters of April to June and July to September. However, for plants with GAC, the highest HAA levels were observed in the quarters of April to June and January to March. This HAA level profile inversely correlated well with water temperature, or biologic activity. For GAC plants, simulated distribution samples matched well with distribution system equivalent samples for Cl₃AA and THMs. For plants with and without GAC, simulated distribution samples overestimated readily biodegradable HAAs in distribution systems. The study indicated that through HAA biodegradation, GAC process plays an important role in lowering HAA levels in finished drinking water.