中国煤砷含量评价

根据聚煤盆地煤炭储量和2001年各省、市自治区煤炭产量,在全国选择代表性煤样研究砷含量.对此次煤砷含量采取3种不同评价方法,得到不同意义的全国煤砷平均含量.①将此次煤样砷算术平均含量6.43mg/kg近似认定为全国煤砷平均含量;②考虑5大聚煤区煤炭储量的权重,计算全国煤砷平均含量为5.28g/kg;③考虑2001年各、省、市自治区煤炭产量的权重,计算全国煤砷平均含量为6.03mg/kg.高砷煤因储量较小,对全国煤砷含量影响较小,可以忽略不计.3种煤砷平均含量意义不同,对于不同的研究目的,应选择不同的煤砷平均含量,这样才能更准确地反映客观真实情况.     

A risk-estimation methodological framework using quantitative assessment techniques and real accidents’ data: Application in an aluminum extrusion industry

The risk estimation presumably is the most crucial part of the entire procedure of assessing hazards/unsafe situations in the work, and especially in the industries’ and constructions’ worksites, where the working conditions are unstable. We can consider the risk as a quantity, which can be estimated and expressed by a mathematical relation, under the help of real accidents’ data. The aim of this work is quadruplicate: (a) the development, elaboration and explanation of two new quantitative risk-assessment techniques, (b) the improvement of specific points of other scientific works, as far as concerns quantitative risk estimation, (c) the application of these techniques on an industrial productive procedure (as a case study) and (d) the comparison of their outcome risk-estimation results. Particularly, we develop and analyze the theoretical background of the two techniques, which we call as “proportional technique” and “decision matrix technique”, and apply them on an aluminum extrusion industry's worksite, which is situated in Greece, by using real data of potential sources of hazards, recorded by safety managers, during the 5.5-year time period of 1999–2004. Comparing the results of the two quantitative risk-assessment techniques, we infer that they are compatible. Therefore, the most important hazard source in the aluminum industry is the “squeezing and hits by dropping objects (transported by derricks)”, and imposes that immediate suppressive measures must be taken place to abolish the danger source.     

Cost/Benefit Considerations for Recent Saltcedar Control,Middle Pecos River,New Mexico

Major benefits were weighed against major costs associated with recent saltcedar control efforts along the Middle Pecos River, New Mexico. The area of study was restricted to both sides of the channel and excluded tributaries along the 370 km between Sumner and Brantley dams. Direct costs (helicopter spraying, dead tree removal, and revegetation) within the study area were estimated to be $2.2 million but possibly rising to $6.4 million with the adoption of an aggressive revegetation program. Indirect costs associated with increased potential for erosion and reservoir sedimentation would raise the costs due to increased evaporation from more extensive shallows in the Pecos River as it enters Brantley Reservoir. Actions such as dredging are unlikely given the conservative amount of sediment calculated (about 1% of the reservoir pool). The potential for water salvage was identified as the only tangible benefit likely to be realized under the current control strategy. Estimates of evapotranspiration (ET) using Landsat TM data allowed estimation of potential water salvage as the difference in ET before and after treatment, an amount totaling 7.41 million m³ (6010 acre-ft) per year. Previous saltcedar control efforts of roughly the same magnitude found that salvaged ET recharged groundwater and no additional flows were realized within the river. Thus, the value of this recharge is probably less than the lowest value quoted for actual in-channel flow, and estimated to be < $63,000 per year. Though couched in terms of costs and benefits, this paper is focused on what can be considered the key trade-off under a complete eradication strategy: water salvage vs. erosion and sedimentation. It differs from previous efforts by focusing on evaluating the impacts of actual control efforts within a specific system. Total costs (direct plus potential indirect) far outweighed benefits in this simple comparison and are expected to be ongoing. Problems induced by saltcedar control may permanently reduce reservoir capacity and increase reservoir evaporation rates, which could further deplete supplies on this water short system. These potential negative consequences highlight that such costs and benefits need to be considered before initiating extensive saltcedar control programs on river systems of the western United States.     

湖南省农业旱灾脆弱性综合分析与定量评价

旱灾是湖南省农业特别是粮食生产可持续发展的严重制约因素。在同一致灾强度下，灾情随灾害脆弱性的增强而加重，降低灾害脆弱性可减轻灾害造成的直接经济损失，因此农业旱灾脆弱性的研究对湖南省减灾和农业可持续发展具有特别重要的意义，湖南省自然生态环境和社会经济状况各异，农业旱灾脆弱性各地不同，选择降水量，蒸发量，水利化程度等9个指标综合评价了各个县市的旱灾脆弱性，并利用GIS技术进行旱灾脆弱性区划，结果表明，湘中衡邵盆地和湘西北山地是农业旱灾严重脆弱带，湖南山地区为强度旱灾脆弱带，沅麻盆地山地区为中度旱灾脆弱带，洞庭湖平原和湘东北山地旱灾脆弱性较小。     

地理气候及湖盆形态对我国湖泊营养状态的影响

利用SPSS统计分析软件的相关性分析和曲线估计功能分析了我国145个湖泊富营养化指标与自然因素之间的关系.富营养化指标包括2008—2010年现场监测的总氮、总磷、高锰酸盐指数、透明度、叶绿素a(Chla)和营养状态综合指数(TLI),自然因素包括:2个湖盆形态指标(平均水深和面积)、3个湖泊地理位置指标(经度、纬度和海拔)和3个气候指标(年均温、年平均降水量和>0℃积温).相关性分析的结果表明,TLI指数与湖泊平均水深和海拔呈显著负相关(p<0.01),而与湖泊所在经度、>0℃积温呈显著正相关(p<0.01,p<0.05).Chla与湖泊平均水深呈显著负相关(p<0.05),与年均温和>0℃积温呈显著正相关(p<0.05).曲线估计的分析结果表明,TLI与湖泊平均水深和经度呈幂函数关系,与海拔和>0℃积温呈指数函数关系.研究结果还表明,贫营养湖泊位于高海拔(>1000m)和低经度(<105°)地区,并且湖泊的平均水深大于30m.年平均降水量低于1000mm,>0℃积温低于5400℃.     

平原感潮河网地区非点源污染负荷匡算

平原感潮河网地区非点源污染严重,由于具有交叉污染等特性,造成了整个平原河网存在严重的环境污染和环境安全问题。构建了大尺度非点源污染负荷匡算模型,对南通平原河网地区非点源污染负荷进行了匡算。根据不同的产污方式,将非点源污染分为城镇降雨径流污染、畜禽养殖污染、农田降雨径流污染、农村生活污染和水产养殖污染等5种类型,分别计算其流失过程。     

畜禽源氨气排放因子估算方法研究

畜禽养殖过程中产生的氨气(NH_3)在人为源NH_3排放中所占的比重较大,对二次气溶胶的形成起重要作用.由于我国畜禽饲养品种多样,各地气候条件和饲养规模存在较大差异,且影响NH_3排放的因素复杂多变,因此,获得准确的畜禽NH_3排放因子较为困难.本文以山西省太原市及其周边地区典型猪场、鸡场、牛场、羊场为实验场所,以杜洛克猪与长白猪的杂交猪、海兰褐蛋鸡、白羽肉鸡、杜泊羊与晋中绵羊的杂交羊、中国黑白花奶牛、金色阿奎丹与西门塔尔杂交肉牛为研究对象,通过3种方法估算它们的NH_3排放因子.结果表明:基于日粮成分和氮代谢沉积率的粗蛋白估算法过程简单、计算便捷、适合所有种类的畜禽,但未考虑NH_3挥发过程中的吸收转化及施肥利用,因而误差较大;基于排泄物含氮率和NH_3挥发率的物质流法涉及粪肥管理的不同阶段,全面考虑了NH_3产生、损失的全过程,与实际情况接近,但参数较多、周期较长、计算过程复杂;基于畜禽舍内NH_3浓度的直接测量法数据来源可靠、参数少,但只能用于相对封闭的环境,不适合牛场和羊场等敞开或半敞开的圈舍,且该方法没有考虑粪尿离开畜禽舍以后的储藏、还田过程,计算结果偏小.通过3种方法的互相印证和比对,猪、奶牛、肉牛、羊、蛋鸡、肉鸡6种实验动物的NH_3排放因子分别为6.90、36.53、22.99、3.94、0.54、0.46 kg·头(只)~(-1)·a~(-1).本研究可以为我国畜禽源NH_3排放因子的本地化测定提供一定的参考,并为准确估算畜禽NH_3排放量、做好农业源NH_3排放清单编制和污染防治工作提供参考.     

利用国产环境减灾卫星遥感信息估测春小麦产量——以内蒙古陈巴尔虎旗地区为例

以内蒙古春小麦产区陈巴尔虎旗为研究实例,采用遥感方法,利用分辨率30 m的国产环境减灾卫星的NDVI数据对春小麦单产进行预测。研究选取了该卫星2009年7月29日春小麦乳黄熟期的NDVI数据,同时,建立其与春小麦单产间关系,运用数理统计与回归分析方法构建了春小麦乳黄熟期的NDVI与其单产的估产模型。利用地面实测春小麦单产对估产模型估测的单产进行精度检验,结果表明,基于影像提取的NDVI与春小麦实测单产有较好的抛物线状(y=cx²+bx+a)相关关系,NDVI与春小麦实测单产的相关关系达到显著水平,其相关系数R为0.87,单产相差160 kg/hm²,相对误差为-3.89%。表明利用国产环境减灾卫星的NDVI与实测春小麦单产建立的估产模型,对成熟前春小麦的单产进行估测,其估产精度也同样可达到与利用国外卫星的预估效益。     

137Cs法用于典型流域土壤侵蚀的初步研究——以太湖流域上游西苕溪流域为例

太湖流域上游土壤侵蚀量对于研究太湖流域营养盐输入和水环境效应具有重要意义。论文运用137Cs示踪分析法对太湖流域上游浙江省安吉县西苕溪流域的土壤侵蚀进行了初步研究,结果表明:该流域的137Cs基准值为2148.8±120.7Bq/m₂;对于非耕作土壤,137Cs在土壤剖面中呈指数型分布,分布深度一般在20cm左右;对于耕作土壤,则在耕作层内呈均一分布,耕作层以下则急剧下降,分布深度达30cm。典型断面研究表明:耕地侵蚀强于非耕地;坡面上部侵蚀强于下部;坡度(0°～20°)与土壤侵蚀强度呈对数正相关关系。     

不同城市机动车尾气排放比较及数据可分享性评价

针对我国绝大多数城市缺乏机动车相关基础数据的实际国情,探讨一种基础数据共享的可能性,用于城市机动车尾气排放清单的计算.以北京、上海、天津及成都4个城市为例,通过综合这些城市现有的机动车相关的基础数据（如机动车保有量,车龄分布,基于驾驶特征的发动机比功率（VSP）,外界环境等）,运用模型预测他们的机动车尾气排放并和相应城...