冬瓜山铜矿安全生产事故统计分析及改进措施

为查找冬瓜山铜矿安全生产事故规律,提出有效的改进措施,预防和减少事故发生,运用三维预防安全管理体系研究成果,对冬瓜山铜矿2003~2013年的安全生产事故,按照严重程度、伤残等级、事故类型等分别进行统计与分析,查找事故发生规律。统计表明,冬瓜山铜矿死亡事故按类别主要以车辆伤害和中毒窒息死亡为多,其次是片帮冒顶;从原因分析看,排在第一的是事故隐患,其次是管理缺陷和违章。针对事故发生的原因,提出了一系列的改进措施,目前这些改进措施已经逐步在冬瓜铜矿得到落实,取得了明显的效果,2012年以来,事故率明显下降,员工安全意识和安全操作技能一定程度得到提高,矿山安全管理环境得到显著改善。     

核电站核事故核素污染评估模式

利用修正了的高斯模式探讨核电站核素污染事故中的核素扩散。分析了边界条件,气象条件和核素衰变规律对核素扩散污染的影响,并进一步讨论了核素的污染范围,距源距离及核素的沉积量,可作为确定应急安全的理论依据。     

Modeling Animal Habitats Based on Cover Types: A Critical Review

The simplest type of model describing animal habitats is a “cover-type model,” in which a species is assumed to be present in certain vegetation types and absent in others. Ecologists and managers use these models to predict animal distributions for gap analysis and conservation planning. Critics, however, have suggested that the models are overly simplistic and inaccurate. We reviewed the use of cover-type models including assessing their error rates, diagnosing the problems with these models, and determining how they should best be used by managers. To determine models’ accuracy rates, we conducted a meta-analysis of 35 studies in which cover-type models were tested against data on animal occurrences. Models had a mean accuracy rate of 0.71 ± 0.18 (SD). Rates of commission error averaged 0.20 ± 0.16, and omission errors averaged 0.09 ± 0.11. A review of the effects of errors in conservation planning suggests that the observed error rates were high enough to call into question any management decisions based on these models. Reasons for the high error rates of cover-type models include the fallibility of expert opinion, the fact that the models oversimplify how animals actually use habitats, and the dynamic nature of animal populations. Given the high rate of errors in cover-type models, any conclusions based on them should be taken with extreme caution. We suggest that these models are best used as coarse filters to identify locations for further study in the field.     

模拟污染指标水体统计分析

介绍了模拟污染水体中各类指标的单回归，逐步聚类分析，主成份分析及逐步判别分析，在聚类图和判虽函数中，溶解氧与色度具有最紧密关系，水中总和氮氮对水质也有显影响。对模拟试验样品，主成份分类与判别分析分类的结果相类似，而对城市河流体品用判别函数别的结果与观察到的天然状态相一致。     

不同土壤中Zn有效态含量与全量关系的统计研究

以"全国重点区域土壤环境质量数据库"为数据源,依据pH值、有机质含量、阳离子交换量筛选出时间、空间分布不连续的3组402个土壤样品,对土壤中Zn有效态含量与全量的相关性进行了统计分析.结果表明,在pH值5.0～6.5、有机质含量1.0%～2.5%,pH值5.0～6.5、有机质含量2.5%～4.0%,pH值7.5～8.5、有机质含量1%～2.5%等3类土壤条件下(阳离子交换量均介于15～30cmol·kg-1),土壤中的Zn有效态含量与全量之间均存在显著的相关性,且均能在Zn有效态含量与全量之间建立起有意义的回归方程.     

塔里木河下游植被覆盖变化遥感定量分析

在RS与GIS技术支持下,采用空间模型分析法,以2 a为一研究时段,定量分析塔里木河下游输水后植被覆盖变化。结果表明:输水11 a来,Ⅳ级低覆盖植被、Ⅴ级裸地及沙地仍是研究区主要地类。与2000年相比,2010年Ⅰ级极高覆盖植被、Ⅱ级高覆盖植被、Ⅲ级中覆盖植被、Ⅳ级低覆盖植被均呈现逐级增加的趋势,分别增加了986.76、 681.84、 1 091.88、 8 641.89 hm²;Ⅴ级裸地、沙地减少了11 420.37 hm²。整个研究时段,Ⅲ级与Ⅳ级间、Ⅳ级与Ⅴ级间的转化为研究区主要转化类型。随着输水次数和年输水量的稳步增加,研究区植被覆盖类型将向覆盖度、面积稳步增长的平衡态发展,而随着输水量的减少,植被覆盖又转向类型变化频繁的非平衡态。植被覆盖度的增减变化客观反映了输水状况(输水量、输水持续时间),持续、稳定的输水是植被覆盖(覆盖度、面积)稳步增长的前提。     

面向生命周期评价的土地利用生态影响评价方法

初步建立了面向生命周期评价(LCA)的适合我国土地利用生态影响评价的指标、特征化因子和影响大小计量模型.评价指标包括土地利用时间、面积、净初级生产力、土壤有机质含量和地形坡度.分别研究确定了基于NPP、土壤有机质含量和地形坡度的特征化因子及其当量系数.提出了基于顶级群落理论的土地利用生态影响评价计量模型.案例应用表明,提出的方法可为我国开展土地利用的LCA提供初步的技术框架和相关参数.     

空气污染健康损失中统计生命价值评估研究

采用权变评价法(CVM)评估了我国空气污染健康损失中的统计生命价值,并分析了其影响因素.结果表明,我国空气污染健康损失中的统计生命价值约为100万元/a.区间值线性回归模型分析显示,年龄、受教育程度、人均年收入、健康和家庭规模等因素对统计生命价值均有显著影响,但是城市的不同对统计生命价值并没有显著影响.     

北运河武清段水污染时空变异特征

通过对北运河武清段水系(主河道——北运河和龙凤河,北运河支流——柳河、灌溉沟渠)的水质进行监测,采用灰色关联法对水质状况进行评价,并利用多元统计法对污染的时空变异特征进行了分析.结果表明,北运河武清段水系17个观测点中有23.8%的观测点的水质为Ⅲ类水,12.7%为Ⅳ类水,63.5%为Ⅴ类水.水质存在时空变异,夏、冬季节各河道水质差异不显著,春、秋季节差异显著.沟渠水质最差,其总磷(TP)含量和BOD5值明显高于其他河道;TP、硝态氮(NO3--N)、COD、总有机碳(TOC)、温度(T)、溶解氧(DO)和总氮(TN)解释了全部的季节性变异,BOD5、pH、溶解性总固体(TDS)和叶绿素a(Chl-a)的季节变异主要受人为因素影响,氧化还原电位(ORP)、氨氮(NH4+-N)和亚硝态氮(NO2--N)次之.NH4+-N和TN解释了51%的空间变异,主河道的氮污染是由上游工厂和企业排放污水造成的;北运河武清段的主要污染物依次为:有机污染物、氨氮、硝态氮、酸碱废水和磷,污染表现为复合污染,点源仍是最主要的污染源.     

Simulating global soil-CO2 flux and its response to climate change

It has been argued that increased soil respiration would become a major atmospheric source of CO2 in the event of global warming. The simple statistical models were developed based on a georeferenced database with 0.5° × 0.5° longitude/latitude resolution to simulate global soil-CO2 fluxes, to investigate climatic effects on these fluxes using sensitivity experiments, and to assess possible responses of soil-CO2 fluxes to various climate change scenarios. The statistical models yield a value of 69 PgC/a of global soil CO2 fluxes for current condition. Sensitivity experiments confirm that the fluxes are responsive to changes in temperature,precipitation and actual evapotranspiration, but increases in temperature and actual evapotranspiration affect soil-CO2 fluxes more than increases in precipitation. Using climatic change projections from four global circulation models, each corresponding to an equilibrium doubling of CO2, it can be found that the largest increases in soil-CO2 fluxes were associated with the boreal and tundra regions. The globally averaged soil-CO2 fluxes were estimated to increase by about 35 ％ above current values, providing a positive feedback to the greenhouse effect.