固定污染源废气监测中有关问题的探讨

针对废气固定污染源监测中存在的一些疑难问题,从工况的确定、断面的选择、间断排放的监测时间、滤筒及过剩系数的影响等方面进行了探讨,提出了一些解决办法。     

Distribution of radionuclides in the guano sediments of Xisha Islands, South China Sea and its implication

Several natural and anthropogenic radionuclides (²¹⁰Pb, ²²⁶Ra and ¹³⁷Cs) in guano-phosphatic coral sediments and pure guano particles collected from Ganquan, Guangjin, Jinqing and Jinyin Islands of the Xisha archipelago, South China Sea, were analyzed. The Constant Initial Concentration (CIC) model and the Constant Rate of Supply (CRS) model were applied for age calculation. The average supply rate of ²¹⁰Pb was 126 Bq m⁻² a⁻¹, very close to the flux of northern hemisphere average (125 Bq m⁻² a⁻¹). The activities of anthropogenic radionuclides in the sediments were very low, indicating that human nuclear tests did not notably impact this region. The main source of radionuclides in the sediments was from atmospheric precipitation, and the organic matter derived from plant and produced by nutrient-rich guano could further enhance them.     

Inverse modeling of Asian Rn flux using surface air Rn concentration

When used with an atmospheric transport model, the ²²²Rn flux distribution estimated in our previous study using soil transport theory caused underestimation of atmospheric ²²²Rn concentrations as compared with measurements in East Asia. In this study, we applied a Bayesian synthesis inverse method to produce revised estimates of the annual ²²²Rn flux density in Asia by using atmospheric ²²²Rn concentrations measured at seven sites in East Asia. The Bayesian synthesis inverse method requires a prior estimate of the flux distribution and its uncertainties. The atmospheric transport model MM5/HIRAT and our previous estimate of the ²²²Rn flux distribution as the prior value were used to generate new flux estimates for the eastern half of the Eurasian continent dividing into 10 regions.The ²²²Rn flux densities estimated using the Bayesian inversion technique were generally higher than the prior flux densities. The area-weighted average ²²²Rn flux density for Asia was estimated to be 33.0 mBq m⁻² s⁻¹, which is substantially higher than the prior value (16.7 mBq m⁻² s⁻¹). The estimated ²²²Rn flux densities decrease with increasing latitude as follows: Southeast Asia (36.7 mBq m⁻² s⁻¹); East Asia (28.6 mBq m⁻² s⁻¹) including China, Korean Peninsula and Japan; and Siberia (14.1 mBq m⁻² s⁻¹). Increase of the newly estimated fluxes in Southeast Asia, China, Japan, and the southern part of Eastern Siberia from the prior ones contributed most significantly to improved agreement of the model-calculated concentrations with the atmospheric measurements. The sensitivity analysis of prior flux errors and effects of locally exhaled ²²²Rn showed that the estimated fluxes in Northern and Central China, Korea, Japan, and the southern part of Eastern Siberia were robust, but that in Central Asia had a large uncertainty.     

Combining sap flow and eddy covariance approaches to derive stomatal and non-stomatal O3 fluxes in a forest stand

Stomatal O₃ fluxes to a mixed beech/spruce stand (Fagus sylvatica/Picea abies) in Central Europe were determined using two different approaches. The sap flow technique yielded the tree-level transpiration, whereas the eddy covariance method provided the stand-level evapotranspiration. Both data were then converted into stomatal ozone fluxes, exemplifying this novel concept for July 2007. Sap flow-based stomatal O₃ flux was 33% of the total O₃ flux, whereas derivation from evapotranspiration rates in combination with the Penman-Monteith algorithm amounted to 47%. In addition to this proportional difference, the sap flow-based assessment yielded lower levels of stomatal O₃ flux and reflected stomatal regulation rather than O₃ exposure, paralleling the daily courses of canopy conductance for water vapor and eddy covariance-based total stand-level O₃ flux. The demonstrated combination of sap flow and eddy covariance approaches supports the development of O₃ risk assessment in forests from O₃ exposure towards flux-based concepts.     

南通地区冰后期泥沙沉积量和环境变化的初步研究

南通地区位于长江三角洲北翼,其冰后期的环境变化以最大海侵时期为界,之前为海侵期,表现为海水入侵,陆地面积减少。之后海面趋于稳定,长江泥沙在河口地区持续沉积的作用下,表现为南通地区的逐渐成陆过程。利用收集的84个分布于南通地区及附近的钻孔剖面资料,将其按不同厚度的沉积相进行整理,结合前人研究成果,根据不同的数据基础运用IDW（Inverse Distance Weighted）插值对南通地区冰后期沉积厚度分布和环境变化过程分别进行了初步研究。结果表明：南通地区古河谷区是冰后期主要的泥沙沉积区,沉积物厚度、体积和重量大于北翼地区,北翼前缘沉积要大于后缘。冰后期古河谷区沉积泥沙4 8922×108 t,北翼地区沉积泥沙1 0453×108 t,二者之比约为47〖DK〗∶10,泥沙沉积强度之比约2〖DK〗∶1。从冰后期海侵初期到最大海侵时期,再到南通成陆的晚期,南通地区水域面积比例先由622%上升到95%,再缩减到331%,陆地面积比例先由378%缩减到5%,而后又上升至669%。尽管钻孔资料可以为南通地区有历史记载之前的时期提供宏观的环境变化框架,但由于钻孔资料在测年数据及沉积相的划分方面分辨率较低,在表现南通地区历史时期的环境变化方面存在不足,需要结合考古、文物等历史资料和土壤分布等自然地理信息进行更为详细的研究     

三峡库区香溪河流域非点源营养盐输出变化的试验研究

综合三峡库区香溪河流域土地利用结构和水系特点,在三大支流出口处设置常规水质监测断面,于干流响滩处设置水文控制断面,通过断面水质水量监测,利用数字滤波法解析径流多源和污染多源,研究上游来流点源和非点源营养盐输出负荷变化。结果表明：受农业非点源污染影响,TN是高岚河（0788 mg/L）＞古夫河（0712 mg/L）＞南阳河（0567 mg/L）;南阳河受磷矿企业点源输入的影响,TP是南阳河（0323 mg/L）＞高岚河（0074 mg/L）＞古夫河（0053 mg/L）;断面流量与降雨量的相关系数〖WTBX〗R〖WTBZ〗2=0720 2;TN和TP非点源年负荷输出分别占总量的61%和40%的, 20100607次降雨径流监测分析发现此次降雨汇流期间营养盐TN和TP输出的非点源贡献率分别达752%和709%;营养盐负荷主要受径流量影响,TN和TP输出负荷与流量的相关系数分别是0963 6和0978 9     

基于适应性管理的水污染控制体系构建——以太湖流域为例

从规划内容与目标、规划方法及方案实施和评估3方面对太湖近20年水污染物控制历程进行综合分析,认为太湖水污染物控制正处面源污染、生活污染及新型污染问题凸显且更难处理,更为广泛的利益相关者和科研队伍积极参与的转型期.这种变化将导致污染治理面临更难应付的动态性和复杂性,使得当前以环境容量为总量为指导通过自上而下分配排污量和削减量的控制方案面临极大挑战.结合太湖水污染现状,通过与现行治理方法在管理假设、适合对象、协调管理手段、管理目标、规划方法、公众参与程度以及规划的优劣势等方面的比较发现,适应性管理可以积极有效应对由于环境趋势和管理协调对象变化所带来的系统不确定性和复杂性,将是一个积极有效的补充方法.同时,本文基于适应性管理提出了太湖水环境污染物排放控制体系的构建框架,突出适应性管理平台、科学研究及公众与基层单位参与在污染物控制中的重要作用.     

基于博弈论的非点源污染控制模型探讨

随着对工业和城市生活污水等点源污染治理能力的不断增强,农业非点源污染对水质环境的影响日益凸现.相对于点源污染,非点源污染发生的不确定时间、不确定途径、不确定量等特点给治理政策的制定带来很大难度.本文从著名的公地悲剧现象出发,着力从市场博弈及政府监督博弈两个模型分析非点源污染制造者之间的博弈格局,并提出以“集体表现”的形式对非点源污染进行管理和控制.市场博弈模型中以一定的排污削减目标为前提,确定以成本最优的原则进行点源-非点源排污权交易是可行且有效率的;而政府监督博弈模型的结果显示:合理的环境补贴和惩罚机制、政府对自身声誉及公众形象的重视及维护对非点源污染治理起正向促进作用.     

Accumulation and maternal transfer of polychlorinated biphenyls in Steller Sea Lions (Eumetopias jubatus) from Prince William Sound and the Bering Sea, Alaska

The western stock of the Steller sea lion (Eumetopias jubatus) in the northern Pacific Ocean has declined by approximately 80% over the past 30 years. This led to the listing of this sea lion population as an endangered species in 1997. Chemical pollution is a one of several contributing causes. In the present study, 145 individual PCBs were determined in tissues of male sea lions from Tatitlek (Prince William Sound) and St. Paul Island (Bering Sea), and placentae from the Aleutian Islands. PCBs 90/101, 118, and 153 were abundant in all the samples. The mean toxic equivalents (TEQ) were 2.6, 4.7 and 7.4 pg/g lw in the kidney, liver, and blubber samples, respectively. The mean TEQ in placentae was 8 pg/g lw. Total PCBs concentrations (2.6-7.9 μg/g lw) in livers of some males were within a range known to cause physiological effects. Further suggesting the possibility of adverse effects on this stock.     

服务江苏环保,投身污染减排——论省环科院在江苏省污染减排中的作用

文中从江苏省环科院的职能出发,阐述了省环科院在江苏省污染减排工作中的地位和作用,指出省环科院应在污染减排工作中做出更大贡献。