某工业场地砷污染的加密布点优化与精度对比分析

场地污染调查是开展场地风险评估和修复的基础,随着我国颁布建设用地土壤风险管控标准等文件,提出风险筛选值和管制值的分级管控体系,我国土壤污染调查工作对于精确掌握污染物浓度梯度及空间分布有了更高的要求,因而如何构建高效采样布点方法变得尤为重要.本研究以南京市某砷工业污染场地为例,开展了优化布点方法与调查精度的研究.首先,在初查数据的基础上,运用指示克里格的方法预测土壤污染概率,参考城市土壤背景值开展阈值设定,提取加密布点区域,之后结合场地历史生产资料与自然信息布设加密点位,最终将插值预测污染结果与非加密、均匀加密、真实情况结果进行对比,验证方法精度.结果表明：本方法符合国际中基于设计抽样以达到场地调查简单、经济、客观的理念,适用于数据存在明显空间相关性的场地;该方法获得的污染区域面积占比为8.32%,与8.57%的现实情况较为接近,但普通法得到的污染面积比相对未加密情况不升反降,可能的原因是在非污染区域增设点位会造成阈值边缘区域在模拟时往清洁区域偏移,污染区域被误判为清洁,反而造成结果偏差;在目前我国环境管理对超阈范围重点关注的背景下,该方法既能够节约布点成本,又精确化预测场地污染超标范围,为后续的场地修复和治理工作提供帮助.     

中外发展循环经济的比较分析

本文就中外发展循环经济的产生背景、发展内涵进行了对比,并简要分析了发达国家循环经济的主要特点,进而对我国发展循环经济提出应采取的措施和做法:一是调整产业结构和布局,建设符合循环经济要求的产业体系;二是健全政策机制,提供法规和制度保障;三是积极创建生态城市和村镇,推动资源节约型和环境友好型社会建设;四是加强宣传引导,营造全社会支持参与的良好氛围.     

地震液化评价方法的对比与讨论--以添立大厦和添富花园工程为例

地震液化的准确判别，对建筑物安全影响颇大。结合添立大厦和添富花园工程具体情况，借鉴美国、法国和德国等在地震液化中采用两种或两种以上的方法做平行分析，进行了该工程的地震液化的评价。对各种评价方法所考虑的因素和侧重点进行了对比，并通过评价结果比较，说明了应用两种以上方法能提高判定的准确性及工程的可靠性。     

亚甲蓝分光光度法测定水中阴离子表面活性剂的探讨

对水中阴离子表面活性剂的测定方法做了一些探讨改进，并用改进方法和目标法分别对已知样和自配样进行了测定比较，结果标准偏差〈1％，效果较好。     

标定低浓度高锰酸钾溶液的方法比较

比较以高锰酸钾本身和邻菲哕啉-Fe^2＋作指示剂，对低浓度高锰酸钾溶液进行标定发现，以邻菲啰啉-Fe^2＋作指示剂的标定，结果更为准确。     

Obtaining Environmental Favourability Functions from Logistic Regression

Logistic regression is a statistical tool widely used for predicting species’ potential distributions starting from presence/absence data and a set of independent variables. However, logistic regression equations compute probability values based not only on the values of the predictor variables but also on the relative proportion of presences and absences in the dataset, which does not adequately describe the environmental favourability for or against species presence. A few strategies have been used to circumvent this, but they usually imply an alteration of the original data or the discarding of potentially valuable information. We propose a way to obtain from logistic regression an environmental favourability function whose results are not affected by an uneven proportion of presences and absences. We tested the method on the distribution of virtual species in an imaginary territory. The favourability models yielded similar values regardless of the variation in the presence/absence ratio. We also illustrate with the example of the Pyrenean desman’s (Galemys pyrenaicus) distribution in Spain. The favourability model yielded more realistic potential distribution maps than the logistic regression model. Favourability values can be regarded as the degree of membership of the fuzzy set of sites whose environmental conditions are favourable to the species, which enables applying the rules of fuzzy logic to distribution modelling. They also allow for direct comparisons between models for species with different presence/absence ratios in the study area. This makes them more useful to estimate the conservation value of areas, to design ecological corridors, or to select appropriate areas for species reintroductions. Received: June 2005 / Revised: July 2005     

二乙氨基二硫代甲酸银光度法与原子荧光法测定水中As的方法比对

二乙氨基二硫代甲酸银光度法和原子荧光法测定水中砷均具有准确度高,精密度好的特点,两种方法的检测结果无显著性差异.     

前后对比分析法在战略环境评价中应用初探

分析战略环境评价基本内涵，提出战略环境评价实施框架，并重点分析了评价战略筛选与评价者确定、战略分析、战略环境影响识另与建立评价指标体系、战略环境影响预测与综合评价以及制定战略环境影响减缓措施等关键问题；初步研究了战略环境评价方法，重点研究前后对比 政策评价方法类型、特点及其在战略环境评价中的应用。最后以长春经济技术开发区战略为例进行实证分析。     

不同处理剂对猪场废水污染物去除效果比较研究

比较了不同处理药剂对猪场废水净化效果，实验表明：化学沉淀法能够较好地去除猪场废水中有机物、磷、重金属、盐分，对氮的去除效果并不理想。投加量为1g·L^-1的FeCl3、聚合硫酸铁、聚合氯化铝、明矾在猪场废水中有较好的絮凝效果，对总磷、悬浮物、CODCr、Cu离子均有很好的去除效果，MgSO4、Mg（OH）2对废水中溶解性总磷也实现了很好的去除效果，氯化钙、硫酸镁、硅土、聚合硫酸铁对废水中Zn有很好的去除效果，而明矾对Zn的去除效果与对Cu的去除效果相反。     

Statistical Estimation and Model Selection of Species-Accumulation Functions

Abstract:  Soberón and Llorente (1993) proposed pure-birth stochastic processes as theoretical models for species-accumulation curves, and these processes have frequently been used to describe the progress of biological inventories. We describe, in algorithmic form, an alternative statistical analysis based on a likelihood approach ( Díaz-Francés & Gorostiza 2002 ) that provides mathematical rigor to the ideas in Soberón and Llorente (1993) and improves the estimation of the models by incorporating the facts that the variance of the error is not constant and that the observations are correlated. Additionally, we used the likelihood ratios between candidate models as an objective procedure for model selection, allowing comparison between the goodness of fit of various models. The software for these statistical methods can now be downloaded off the Internet. We used two examples of butterfly data sets to illustrate the use of the methods and the software.