Groundwater risk assessment at a heavily industrialised catchment and the associated impacts on a peri-urban wetland

Industrial and agricultural activities often impose significant pressures to the groundwater quality and consequently degrade wetland ecosystems that depend mostly on subsurface water flow. Groundwater vulnerability and risk mapping is a widely used approach to assess the natural protection of aquifers and the associated pollution potential from human activities. In the particular study, the relatively new Pan-European methodology (COP method) has been applied in a highly industrialized peri-urban wetland catchment, located close to Athens city, to map the intrinsic vulnerability of the aquifer and evaluate the risk potential originating from local land uses. Groundwater analysis results for various parameters, including Phenols, PCBs and nutrients, have been used to validate the vulnerability and risk estimations while a biological assessment occurred to associate the mapping results with the wetland's ecological status. The results indicated that even though the natural protection of the aquifer is relatively high due to the dominant hydrogeologic and geomorphologic conditions, the groundwater pollution risk is considerable, mainly because of the existing hazardous land uses. The water quality of the groundwater accredited these findings and the ecological status of this peri-urban wetland also indicated significant impacts from industrial effluents.     

扎龙湿地价值货币化评价

针对湿地特点,把湿地价值分为使用价值和非使用价值两大类,并提出了目前非使用价值的概念。在分析了扎龙湿地价值类型后,采用市场价值法、费用支出法、旅行费用法、影子价格法等不同的方法,对扎龙湿地的使用价值进行了货币化评估;并将CVM法用于湿地经济价值研究,用WTP调查的方法探索了扎龙湿地非使用价值(包括备选、半备选价值)。评估结果表明扎龙湿地的总价值达1564676.96×104元,其中,使用价值1126576.96×104元,非使用价值438100×104元,目前非使用类价值合计493400×104元。这是一种尝试性、探索性研究。     

Issues and impacts of Redwood National Park expansion

In 1968, Redwood National Park was created in an atmosphere of controversy and compromise to preserve remnants of the coastal redwood (Sequoia sempervirens) ecosystems and the streams and seashores with which they are associated. The 1968 boundary included the lower portions of several watersheds in the park, which meant that potential impacts from upstream, privately owned lands might occur. Between 1968 and 1978, controversy continued between preservation and forest industry interests over the impacts of harvesting old growth timber upslope and upstream from the park. In 1978, the southern portion of the park around Redwood Creek was expanded by 48,000 acres, moving the boundary from a narrow, one-half mile riparian corridor to ridgelines, but still leaving two-thirds of the total watershed outside of the park. The park expansion has generated biological and social impacts and opportunities. Meeting the objectives of the 1978 legislation will require close coordination between federal and state government and local communities.     

扎龙湿地芦苇叶片结构与生境关系的研究

本文分别对扎龙湿地不同生境芦苇叶片的上、下表皮及横切面结构进行了细致的观察、比较和分析。结果表明:不同生境中的芦苇表现出不同的适应其生境的特征,主要表现在表皮细胞大小、气孔大小、数量、气孔在叶表面的覆盖面积以及表皮毛的有无上。芦苇在进化过程中为适应不同的生境形成了不同的叶片显微结构。     

长江口东滩湿地柱状沉积物中多氯联苯的分布和变化趋势

采用同位素稀释质谱法,用高分辨率气相色谱-高分辨率质谱仪(HRGC-HRMS)对长江口崇明东滩湿地柱状沉积物30个层段中7种指示性多氯联苯(PCB28,PCB52,PCB101,PCB118,PCB153,PCB138和PCB180)的含量进行了测定. 结合近几十年长江下游气候变化情况,对PCBs垂直分布历史记录特征以及异构体的物理化学性质参数进行了探讨. 结果表明,w(PCBs)为0.138～0.400 ng/g(以干质量计,下同),平均值为0.228 ng/g,属于轻度污染. 东滩沉积物中PCBs呈现明显的周期性分布,在20世纪50年代初期开始快速增长,高峰期出现在70年代,之后呈减少趋势,反映了世界主要生产国家禁止生产PCBs的情况.      

西溪国家湿地公园水质时空分异特征研究

西溪湿地公园作为第一个国家湿地公园和城市湿地公园的代表,具有特殊的功能特征.利用2009年春夏两季对西溪湿地水质的月监测数据,揭示城市湿地公园水质时空分异和污染特征.结果表明,①湿地水质空间分异与公园功能特征密切相关.其中,自然水塘的TN、TP平均值分别为0.78 mg/L和0.07 mg/L;观赏水塘TN、TP平均值分别为1.37 mg/L和0.17 mg/L;自然河溪水质TN、TP的平均值分别为2.91 mg/L和0.18 mg/L;游览水道TN、TP平均值分别为1.91 mg/L和0.09 mg/L;②湿地水体富营养化程度时间变化显著.西溪湿地水质的春季富营养化程度小于夏季,总体处于中度富营养化状态;③不同功能湿地水体富营养化程度差异明显.水塘水体富营养化程度低于河溪富营养化程度,其中,自然水塘水质的富营养化程度低于观赏水塘的水质,相反,游览河溪水质富营养化程度低于自然河溪的水质.因此,加强对观赏水塘和自然河溪的管理,是提高西溪湿地水质的有效方法.     

崇明岛湿地沉积物中六六六的长期变化趋势

采用同位素稀释质谱法,利用高分辨率气相色谱-高分辨率质谱法(HRGC-HRMS)分析测定了崇明岛东滩柱状沉积物样品的30个层段中HCHs的含量,对其垂直分布特征进行了初步探讨。沉积物中HCHs均被检出。东滩湿地沉积物中总∑HCHs含量范围为0.35~0.98ng·g-1dw,平均值为0.64ng·g-1dw,属于轻度污染。HCHs呈现明显的周期性变化。采用时间序列分析方法,统计分析了近60年来东滩湿地沉积物中HCHs变化的总体趋势与主要振荡周期。长期变化趋势表明东滩沉积物中HCHs在上世纪50年代初开始增长,高峰期出现在上世纪60至70年代。一些异构体在我国停止生产HCHs后,没有明显的下降趋势。频谱分析结果表明HCHs的分布表现出具有周期为大约8年的振荡特征,可能与气候变化周期相关。     

污水湿地处理工程水力停留时间的测定

利用ＵＡＰ对一个湿地处理工程的实际水力停留时间进行了测定,进而对相关问题进行了探讨。     

Mercury in Tree Swallow Food, Eggs, Bodies, and Feathers at Acadia National Park, Maine, and an EPA Superfund Site, Ayer, Massachusetts

We monitored nest boxes during 1997–1999 at Acadia National Park, Mt. Desert Island, ME and at an old-field site in Orono, ME to determine mercury (Hg) uptake in tree swallow (Tachycineta bicolor) eggs, tissues, and food boluses. Also, in 1998–1999 we monitored nest boxes at Grove Pond and Plow Shop Pond at a U.S. Environmental Protection Agency Superfund site in Ayer, MA. We recorded breeding success at all locations. On average among locations, total mercury (THg) biomagnified 2 to 4-fold from food to eggs and 9 to 18-fold from food to feathers. These are minimum values because the proportion of transferable methyl mercury (MeHg) of the THg in insects varies (i.e., 35%–95% of THg) in food boluses. THg was highest in food boluses at Aunt Betty Pond at Acadia, whereas THg in eggs was highest at the Superfund site. A few eggs from nests at each of these locations exceeded the threshold (i.e., 800–1,000 ng/g, wet wt.) of embryotoxicity established for Hg. Hatching success was 88.9% to 100% among locations, but five eggs failed to hatch from 4 of the 11 clutches in which an egg exceeded this threshold. MeHg in feathers was highest in tree swallows at Aunt Betty Pond and the concentration of THg in bodies was related to the concentration in feathers. Transfer of an average of 80%–92% of the Hg in bodies to feathers may have enhanced nestling survival. Residues of Hg in tissues of tree swallows in the Northeast seem higher than those of the Midwest.     

Mercury Contamination of Biota from Acadia National Park, Maine: A Review

We reviewed literature reporting both total and methylmercury from biota from Acadia National Park, Maine, USA. Our review of existing data indicates that 1) mercury contamination is widespread throughout the Park’s various aquatic ecosystems; 2) mercury pollution likely represents a moderate to high risk to biota inhabiting the Park; and 3) biota at all trophic levels possess elevated concentrations of both total and methylmercury. Watershed fire history and the resulting post-fire forest succession patterns are an important landscape attribute governing mercury cycling at Acadia National Park. Therefore, park service personnel should consider these factors when planning and implementing Hg biomonitoring efforts. Additional baseline funding from the National Park Service for Hg research and biomonitoring will likely be required in order to further evaluate the spatial and temporal patterns of mercury contamination in the park’s biota. An erratum to this article can be found at