大鹏湾环境容量研究Ⅱ:环境容量规划

采用基于响应场的线性规划方法,考虑非点源与湾外污染物输入形成的本底值,结合深圳沿岸排污口的分布计算了大鹏湾的环境容量,并给出了总量分配方案.结果表明,大鹏湾物理自净能力差,但水体容量大,具有较大的稀释容量,加上污染物的生化降解,大鹏湾具有较大的环境容量.BOD5、总氮、总磷的最大允许排放总量分别为79.0,11.418,0.86t/d,BOD5、总氮、总磷的剩余环境容量分别为61.34,9.318,0.43t/d.     

海州湾生态系统健康诊断

根据开敞海湾浅海生态系统特征,构建了包含环境现状、环境风险、环境背景、系统结构功能和系统稳定性5类诊断指标以及24个诊断因子的浅海生态系统健康诊断指标体系,并采用层次分析法对海州湾浅海生态系统2009年12月和2010年11月的健康状况进行诊断.结果表明,2009年12月和2010年11月海州湾浅海生态系统的综合健康指数值分别为0.500～0.689和0.553～0.750,浅海生态系统处于亚健康～较健康状态,近岸海域基本处于亚健康状态,离岸海域基本处于较健康状态,近岸海域生态系统健康水平低于离岸海域,这与近岸海域开发活动干扰多以及环境压力大有关.     

海岸带表层沉积物中磷的地球化学特征

通过连续提取法对莱州湾主要入海河流及近岸海域表层沉积物中5种形态磷进行了定量分析.结果表明,近海沉积物自生钙结合磷含量(45.6%)高于河流(37.3%),而铁结合磷(Fe-P)含量(18.2%)却低于河流(31.3%).在近海,可交换或弱结合磷含量和粉砂比例呈正相关,表明该形态磷主要吸附于细粒粉砂．河流沉积物Fe-P与Fe浓度呈显著正相关(P<0.01),表明河流沉积物Fe-P分布受沉积物活性铁含量的控制．河口处Fe-P普遍低于相应河流,这可能与海相泥沙输入及河口厌氧区硫酸盐还原或硫化物累积有关.近海沉积物总可提取态磷平均浓度总体呈现出由海洋向河口方向递减的趋势.     

渤海湾表层沉积物各形态重金属的分布特征与生态风险评价

根据2008年春对渤海湾的调查,通过分级萃取的实验方法以及总量和分形态风险评价的手段,重点研究了渤海湾表层沉积物各形态重金属的分布特征、影响因素和潜在生态风险.结果表明,重金属在渤海湾中央的泥质区富集,自然来源是控制V、Ni、Cu、Pb、Co和Cd分布的主要因素,而Zn和Cr较易受环境变化或人为输入等影响,其中Pb作为大气沉降和陆源输入都存在的重金属,其受控因素与其他重金属有一定差异.形态分析表明,V、Zn和Cr以残渣态为主,Co、Ni和Cu则是可浸取态占优势.其中Co的可浸取态质量分数在A断面先增加后降低,Ni的可浸取态质量分数在海河口附近A3站达最大值(98.86%),Cu和Pb的可浸取态高值区出现在A断面的中央区域,优势形态是铁锰氧化物结合态,Cu在湾口的A10站降到最小值(43.83%),在黄河口的D1站达最大值(73.89%).风险评价表明,重金属总量富集因子由大到小:Pb>Cd>Zn>Cr>V>Co>Cu>Ni,其中Pb、Cd和Zn的富集因子均大于1,但渤海湾沉积物总体质量良好,潜在生态风险较低.从形态角度评价,V和Cr基本无污染,Zn局部轻微污染,Co大部分轻度污染,Cu由无污染到中度污染,Ni由轻度污染到重度污染,Pb则属重度污染,其中Pb在渤海湾口A11站的P%(次生相与原生相分布比值)达1 329%.综合评价得出,Pb是渤海湾沉积物污染最严重的重金属,Cu和Zn有潜在污染,V、Cr和Co基本清洁.     

粤港澳大湾区生态环境监测发展现状与展望

"十四五"期间,粤港澳大湾区将会迎来新一轮大开发、大建设、大发展,绿色发展与山水林田湖草一体化保护将面临更大的机遇与挑战。生态环境监测作为生态环境保护的重要基础,亟需强化支撑、引领、服务作用。文章对粤港澳大湾区生态环境监测发展现状进行了梳理,从环境质量状况、生态环境管理、环境监测网络等方面将粤港澳大湾区与东京、纽约、旧金山三大世界级湾区进行系统比较,对标查找差距与不足,并对面临的机遇与挑战进行了深入剖析。在此基础上,针对生态环境监测区域布局、现代感知网络、智慧应用与"美丽湾区"综合评价、联合监测与信息发布、产学研用一体化等方面,提出了粤港澳大湾区当前及今后一个时期生态环境监测发展的相关建议。     

区域大气污染的城市网络关联分析--基于粤港澳大湾区的研究

选取2013—2016年粤港澳大湾区11市大气主要污染物数据,采用社会网络分析法(SNA)对粤港澳大湾区大气污染的空间关联性进行实证研究。结果发现:①大湾区城际大气主要污染物的空间关联均呈现出较典型的网络结构特征。②城际大气污染存在明显的空间关联和空间溢出,各城市空间联系越来越密切。③大湾区大气污染空间网络具有稳定性特征,PM2.5和SO2的空间溢出得到有效控制,而PM10和NO2的空间溢出具有长期稳定性。④珠海、佛山、惠州、中山在大湾区城际大气污染空间关联网络中处于中心地位。⑤各城市在大气污染空间网络中存在明显的非均衡地位。     

Observed Winter Warming of the Chesapeake Bay Estuary (1949–2002): Implications for Ecosystem Management

A large number of studies have documented 20th century climate variability and change at the global, hemispheric, and regional levels. However, understanding the implications of climate change for environmental management necessitates information at the level of the ecosystem. Historical monitoring data from the Chesapeake Bay estuary were used to identify temporal patterns of estuarine temperature anomalies in the surface (1 m) and subsurface (15 m) between 1949 and 2002. Data indicated a trend in surface and subsurface warming of +0.16°C and +0.21°C per decade, respectively, driven by warming during winter and spring. These trends suggest warming of the estuary since the mid-20th century of approximately 0.8–1.1°C. Estuarine temperatures correlated well with other independent data records for sea surface and surface air temperatures in the region and to a lesser extent, the northern hemisphere. Gross long-term temperature variability in the estuary was consistent with North Atlantic climate variability associated with the prolonged positive North Atlantic Oscillation/Arctic Oscillation and increased anthropogenic radiative forcing, although localized environmental drivers likely are important as well. A simple spatial analysis revealed strong seasonal latitudinal and longitudinal gradients in estuarine temperature as well as a north–south gradient in long-term temperature trends. Continued warming of the estuary will have important implications for ecosystem structure and function as well as attempts to manage existing challenges such as eutrophication and benthic hypoxia. However, such management efforts must be cognizant of the effects of various climate and nonclimate drivers of environmental variability and change operating over different spatial and temporal scales.Published online     

Integrating Economic Development and the Environment: Artisan Fishing Production in Guanabara Bay,Rio de Janeiro

The adoption of environmentally sustainable techniques by cooperatives and small companies results in specific difficulties rarely discussed in the literature. This paper describes an action-research carried out by seafood cultivators and university researchers in Guanabara Bay, which resulted in the substitution of the previous technique, based on extraction, by one without negative environmental impacts. The economic results have been satisfactory, so it can be expected that this activity may become more widespread in the region.     

Nature and fate of Hudson Bay permafrost

Two aspects of the permafrost of the Hudson Bay region are examined. The first is the climatological conditions that support permafrost especially along the southwestern shore of Hudson Bay. The second is the fate of the permafrost using recent climate change scenarios. The continuous permafrost along the shores of southwestern Hudson Bay is examined from a climatological perspective. Two hypotheses are explored to explain the presence of continuous permafrost in this region in spite of the relatively "warm" local climate. Possible errors in the calculation of thawing degree days and the asymmetries in frozen and unfrozen soil thermal conductivities are successively examined. Only the second hypothesis is likely to explain the presence of permafrost in southwestern Hudson Bay. Sophisticated climate models are used to assess the potential change in permafrost distribution in the Hudson Bay region. Nine simulations using three different versions of the Canadian Centre of Climate Modelling and Analysis (CCCma) general circulation model are used to project permafrost distribution. Two surface temperature thresholds, –5 and –10 °C, are used to diagnose permafrost grid points. All simulations, including those that include reduction of CO₂ emissions, showed at least a 50% reduction of permafrost by 2100 using these temperature thresholds. Electronic Publication     

AN ANALYSIS OF WATER RESOURCES CONSTRAINTS ON POWER PLANT SITING IN THE MID-ATLANTIC STATES1

ABSTRACT: Expansion of the electrical generation system in the Pennsylvania-Jersey-Maryland power pool will impact, and be constrained by, inland water availability. Future interpretations of the Federal Water Pollution Control Act Amendments of 1972 regarding evaporative cooling towers for coastal power plants, offshore siting and energy centers, and the policies and public acceptability of low flow augmentation reservoirs are some of the issues examined in this paper using scenarios generated by the Brookhaven National Laboratory Regional Energy Facility Siting Model (REFS). REFS is a multicommodity, transshipment-location linear programming model used here to allocate power plants among counties in a power pool under a minimization of cost objectives. The solutions are sensitive to the water resources assumptions in the model. For the year 2000, the amount of low flow augmentation allowed in the region's river basins and whether off-shore siting becomes a reality are the two water resources related issues which most affect the scenarios. The results show that decisions regarding specific water problems can have region wide implications for water and nonwater related issues.