Characterization of seawater and aerosol particle surfactants using solid phase extraction and mass spectrometry

Surface-active organic molecules (surfactants) may influence the ability of an aerosol particle to act as a cloud condensation nuclei by reducing its surface tension. One source of organic mass in aerosol particles, which may also contain surfactants, is bubble bursting on the sea surface. In order to directly compare these molecules in the ocean and aerosol particles, we developed a method using multiple solid phase extractions and high resolution mass spectrometry to characterize surface active organic molecules in both. This method has extraction efficiencies greater than 85%, 75%, and 60% for anionic, cationic, and nonionic surfactant standards, respectively. In this study, we demonstrate the presence of three ionic classes of surface active organics in atmospheric aerosol particles and estuarine water from Skidaway Island, GA. With this extraction method, organic molecules from both estuarine water and atmospheric aerosol particles significantly reduced surface tension of pure water (surface tension depression of ~ 18 mN/m) and had high ratios of hydrogen to carbon (H/C) and low ratios of oxygen to carbon (O/C), indicative of surfactants. While previous work has observed a larger fraction of anionic surface active organics in seawater and marine aerosol particles, here we show cationic surface active organics may make up a large fraction of the total surface active molecules in estuarine water (43%–47%).     

两淮采煤沉陷积水区水体初级生产特征

在淮南潘谢矿区设置3个研究站点(PXPJ、PXGQ和PXXQ),在淮北朱-杨庄矿区内设置2个研究站点(HBZH和HBNH),于2012年和2013年分4个季度对两淮采煤沉陷积水区水体的初级生产力及碳(C)的形态特征进行了研究,其中C形态分溶解无机碳(DIC)、溶解有机碳(DOC)和颗粒有机碳(POC),并以此为基础分析了初级生产力与C形态及其它环境因子的相关关系.研究结果表明:受区域地理气候、水化学特征和矿区生态环境等方面影响,5个研究站点水体营养状态、初级生产力及C形态等存在着较大的跨度范围. 5个站点4个季度研究期间叶绿素a(Chla)浓度均值范围为3.7~71.5mg/m3,POC浓度均值范围为0.9~4.0mgC/L,总初级生产力(GPP)均值范围82.4~2305.4mgC/(m2?d), 淮南沉陷积水区水体营养状态和初级生产力明显高于淮北沉陷积水区.5个研究站点水体初级生产力和氮磷含量、Chla、DOC和POC具有显著的正相关性.最后根据研究结果针对性地提出了两淮矿区水生态区生态系统重建、恢复与保护的差别化原则.     

气候变化情景下湿地净初级生产力风险评价

采用BIOME-BGC模型,模拟了气候变化情景下(A1B, A2, B2)三江平原富锦地区小叶章(Calamagrostis angustifolia)湿地的净初级生产力(NPP)变化,并通过NPP变化情况评价小叶章湿地风险等级.结果表明:未来30年(2013~2042年)各气候情景下富锦小叶章湿地NPP均值均高于基准期均值(1961~1990), A1B和B2情景下未来30年间NPP波动范围变大,A2情景下NPP有降低趋势.风险评价结果表明,气候变化情景下小叶章湿地存在一定风险,尤其是在A1B情景下,未来30年中可能有6年以上的年份存在高风险,A2情景下湿地风险最低.湿地NPP变化与降水量呈显著正相关(R2=0.58,P<0.05),说明降水量是影响区域湿地的重要因素.尽管气候变化情景下假设了存在升温?CO2浓度升高等有利于植物生长的因素,但降水量的的剧烈变化以及极端气候事件的增加,可能会导致湿地在未来气候变化情景下面临较高风险,未来湿地保护与管理过程中应重点关注水的补给和调配.     

Kinetic study of phytotoxicity induced by foliar lead uptake for vegetables exposed to fine particles and implications for sustainable urban agriculture

At the global scale, foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere. However, the kinetics of metal uptake, translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles (PM). Different leafy vegetables (lettuces and cabbages) cultivated in RHIZOtest® devices were, therefore, exposed in a greenhouse for 5, 10 and 15 days to various PbO PM doses. The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration. A significant Pb accumulation in leaves (up to 7392 mg/kg dry weight (DW) in lettuce) with translocation to roots was observed. Lead foliar exposure resulted in significant phytotoxicity, lipid composition change, a decrease of plant shoot growth (up to 68.2% in lettuce) and net photosynthesis (up to 58% in lettuce). The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage. Air quality needs, therefore, to be considered for the health and quality of vegetables grown in polluted areas, such as certain megacities (in China, Pakistan, Europe, etc.) and furthermore, to assess the health risks associated with their consumption.     

生态环境损害赔偿磋商制度探析 ——基于十大典型案件的考察

本文以2020年生态环境部公布的生态环境损害赔偿磋商十大典型案件为例,从磋商组织形式、公众参与和赔偿协议履行保障措施三大关键要素考察了我国生态环境损害赔偿磋商制度实行情况,发现磋商实例中存在磋商过程组织形式不统一、公众参与缺失以及履行赔偿协议时司法确认存在不足等规范性问题,并据此提出了健全我国生态环境损害赔偿磋商制度的相关建议。     

“三下”开采资源补偿费减征的模型与方法研究

针对我国“三下”开采资源补偿费征收现状与存在问题,基于资源价值理论及现行资源补偿费征收标准,通过理论分析、实例计算和计算机模拟,给出了“三下”开采资源补偿费减征的理论依据,提出了“三下”开采资源回收难度综合评价模型、补偿费征收模型、合理采出率等有关参数的确定模型,研究了“三下”边界及压煤量、采出率快速准确确定方法,设计开发了程序系统,为搞好“三下”资源补偿费征收、提高矿产资源管理与科学决策水平提供了理论与方法依据。     

Cross-boundary transport and source apportionment for PM2.5 in a typical industrial city in the Hebei Province, China: A modeling study

Cross-boundary transport of air pollution is a difficult issue in pollution control for the North China Plain. In this study, an industrial district (Shahe City) with a large glass manufacturing sector was investigated to clarify the relative contribution of fine particulate matter (PM_2.5) to the city's high levels of pollution. The Nest Air Quality Prediction Model System (NAQPMS), paired with Weather Research and Forecasting (WRF), was adopted and applied with a spatial resolution of 5 km. During the study period, the mean mass concentrations of PM_2.5, SO₂, and NO₂ were observed to be 132.0, 76.1, and 55.5 μg/m³, respectively. The model reproduced the variations in pollutant concentrations in Shahe at an acceptable level. The simulation of online source-tagging revealed that pollutants emitted within a 50-km radius of downtown Shahe contributed 63.4% of the city's total PM_2.5 concentration. This contribution increased to 73.9±21.2% when unfavorable meteorological conditions (high relative humidity, weak wind, and low planetary boundary layer height) were present; such conditions are more frequently associated with severe pollution (PM_2.5 ≥ 250 μg/m³). The contribution from Shahe was 52.3±21.6%. The source apportionment results showed that industry (47%), transportation (10%), power (17%), and residential (26%) sectors were the most important sources of PM_2.5 in Shahe. The glass factories (where chimney stack heights were normally < 70 m) in Shahe contributed 32.1% of the total PM_2.5 concentration in Shahe. With an increase in PM_2.5 concentration, the emissions from glass factories accumulated vertically and narrowed horizontally. At times when pollution levels were severe, the horizontally influenced area mainly covered Shahe. Furthermore, sensitivity tests indicated that reducing emissions by 20%, 40%, and 60% could lead to a decrease in the mass concentration of PM_2.5 of of 12.0%, 23.8%, and 35.5%, respectively.     

中国矿产资源基地划定指标体系构建与应用——以铁矿为例

矿产资源基地是优化中国矿产资源勘查开发布局、保障国内资源有效供应的战略核心区域。在分析基地布局影响因素的基础上,从资源基础、开发条件、市场需求和国家战略等方面构建了矿产资源基地划定指标体系。其中资源基础包括预测资源量、查明资源储量和设计开采规模,开发条件包括缺水程度和交通优势度,市场需求包括后续冶炼加工企业布局与产值,国家战略主要体现为区域协调发展战略对矿产资源基地布局的要求。在此基础上,以铁矿为例开展了实证研究,采用聚类分析、核密度估计等方法对各单项指标进行了分析评价,在全国识别了辽宁鞍山—本溪等12个铁矿资源基地。研究结果可以为“十四五”时期中国矿产资源基地调整优化提供参考,对其他矿产资源空间政策区的划定具有一定借鉴意义。