辽东湾沿岸贝类和环境中的粪大肠菌和细菌总数

对辽东湾沿岸海域几种主要经济贝类体内及其生存环境中的粪大肠菌群和细菌总数进行了调查与研究。结果表明,贝类中粪大肠菌群超标率为53.8%;表层海水中超标率为46.2%;表层沉积物中超标率为12.5%。各种样品中细菌总数的检出结果也表明,该沿岸海域环境和贝类受到了一定的有机污染影响。     

粤港澳大湾区大气中硝基多环芳烃污染特征与风险评估

为探究粤港澳大湾区硝基多环芳烃(NPAHs)污染特征与来源,利用大气主动采样技术采集44个环境空气样品,并使用气相色谱-三重四级杆串联质谱测定NPAHs浓度.结果表明,同时使用滤膜、PUF和XAD-2树脂,可以更高效采集到气态和颗粒态的NPAHs,准确表征环境空气中NPAHs的污染状况.粤港澳大湾区环境空气中ρ(∑18...     

Interactions of warming and altered nutrient load timing on the phenology of oxygen dynamics in Chesapeake Bay

The effects of nutrient loading on estuaries are well studied, given the multitude of negative water quality and ecosystem effects that have been attributed to excess nitrogen and phosphorus. A current gap in this knowledge involves the sensitivity of seasonal cycles of estuarine biogeochemical processes to direct (warming) and indirect influences (nutrient load timing) of climate change. We used a coupled hydrologic–biogeochemical model to investigate changes in the phenology of hypoxia and related biogeochemical processes in Chesapeake Bay under three different hydrologic regimes. Shifts to earlier nutrient load timing during idealized simulations reduced the overall annual hypoxic volume, resulting from discernable, but relatively small reductions in phytoplankton biomass and both sediment and water-column respiration. Simulated increases in water temperature caused an increase in spring/early summer hypoxic volume associated with elevated respiration rates, but an associated exhaustion of organic matter in the early summer caused a decrease in late summer/fall hypoxic volume due to lowered respiration. Warming effects on hypoxia were larger than nutrient timing effects in scenarios where warming was restricted to spring and when it was applied to all months of the year. These idealized simulations begin the process of understanding the potential impacts of future climatic changes in the seasonal timing of key biogeochemical processes associated with eutrophication.     

Eutrophication and Consumer Control of New England Salt Marsh Primary Productivity

Abstract:  Although primary productivity in salt marshes is thought to be controlled by physical forces, recent evidence suggests that human disturbances can drive a switch to consumer control in these ecologically valuable ecosystems. We tested the hypothesis that nitrogen enrichment can trigger consumer control in salt marshes in Narragansett Bay, Rhode Island, with (1) a field experiment in which we manipulated nutrient availability (with nutrient additions) and insect herbivory (with insecticide application), (2) a survey of 20 salt marshes that examined the relationship between marsh nutrient status and herbivore pressure, and (3) insect herbivore removal at high and low nutrient input sites to directly test the hypothesis that nutrient enrichment is increasing insect herbivory in these marshes. Experimental nitrogen eutrophication initially increased plant productivity but eventually led to reduced plant biomass due to insect herbivory, and our surveys revealed that marsh nitrogen supply was a good predictor of herbivore damage to plants. Insects had minimal impacts on primary productivity in pristine marshes, but suppressed primary productivity in eutrophic salt marshes by 50–75%. Thus, eutrophication is currently triggering consumer suppression of primary productivity in New England salt marshes and may ultimately jeopardize the ecological and societal services these systems provide.     

象山港经济贝类中有机氯农药和多氯联苯的残留水平及其变化趋势

对分布于象山港海域的经济贝类中有机氯农药和多氯联苯的含量用气相色谱方法进行测定,结果显示:HCHS为(2.26~12.65)×10-9,DDTS为(7.32~27.25)×10-9,PCBs(13.54~22.57)×10-9;经济贝类中的有机氯农药的组分特征为HCHs中-βHCH占优势,DDTs中DDD和DDE占绝对优势;2001年至2003年HCHs、PCBs含量总体呈微弱下降趋势,而DDTs含量在2003年明显上升;各海区缢蛏中HCHs、DDTs、PCBs残留量均呈西店(港底)<西周(港中)<西泽(港口)。     

Heavy Metal Pollution Assessment in Sediments of the Izmit Bay, Turkey

Surface sediments in the fraction < 63 μm collected from eight stations along the north coastline of Izmit Bay, north-eastern Marmara Sea, Turkey, were analyzed for major (organic carbon, Al, Ba, Fe and Mg) and trace (As, Cd, Co, Cr, Cu, Mo, Ni, Pb and Zn) elements by using inductively coupled plasma atomic emission spectrometry (ICP-AES). Sediments heavily contaminated are evaluated by the Sediment Quality Guidelines (SQG) of US EPA. The results were compared with the marine sediment quality standards (SQS), as well as literature values reported to assess the pollution status of the sediments. The enrichment factors (EFs) were calculated to evaluate actual level of contamination for all the elements using the earth crust as reference matrix, based on elemental values by Mason which show a normal pattern near to unity. The analysis revealed two groups of elements: (i) Arsenic, Cd, Pb, and Zn are the most enriched elements; (ii) Barium, Co, Cr, Cu, Fe, Mg, Mo and Ni are at background levels. The results show that road traffic run-offs, paint industries and coal combustion are among the most significant sources.     

A More Cost-Effective Emap Benthic Macrofaunal Sampling Protocol

Benthic macrofaunal sampling protocols in the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) are to collect 30 to 50 random benthic macrofauna [defined as animals retained on a 0.5 mm (East and Gulf Coasts, USA) or a 1.0 mm mesh sieve (West Coast, USA)] samples per reporting unit using a 0.044 m² (East and Gulf Coasts) or 0.1 m² (West Coast) grab. Benthic macrofaunal community conditions in the reporting unit are characterized by cumulative distribution functions (CDFs) on end points of interest, such as number of species (S), abundance (A), and Shannon--Wiener diversity (H′). An EMAP and a companion field study were conducted concurrently in Tillamook Bay (Oregon, USA) to compare the cost effectiveness of benthic macrofauna samples collected using the EMAP West Coast (0.1 m² × ≥7 cm deep, 1.0 mm mesh), a 0.01 m² × 5 cm deep, 1.0 mm mesh, and a 0.01 m² × 5 cm deep, 0.5 mm mesh sampling protocol. Cost was estimated in relative laboratory sample-processing time. Sampling protocols were judged equally effective for EMAP purposes if, after linear transformation to adjust for scale changes in end point distributions, their S, A, and H′ CDFs were not significantly different. The 0.01 m² × 5 cm deep, 1.0 mm mesh sampling protocol was the most cost effective.     

A System Dynamics Model for the Environmental Management of the Sepetiba Bay Watershed, Brazil

In the recent past, the Sepetiba Bay watershed, located in the Rio de Janeiro State, Brazil has experienced rapid industrial development and population growth, as well as an increase in water pollution and environmental degradation. To analyze the complex interrelationships among the agents affecting the Sepetibza Bay environment, a system dynamics model was developed. The model builds on extensive studies conducted for the watershed, and simulates different hypotheses of economic growth and of demographic expansion. Thus, it can be used as a decision support tool for the identification of investment priorities and policy analyses under various scenarios. In order to provide a comprehensive approach to the environmental management of the Sepetiba Bay watershed, the model had to consider only the most relevant aspects of the behavior and the key interactions among agents operating in the watershed. In this article, the model’s structure is presented together with some of its main results.     

旅游活动对滨海浴场水环境影响研究

基于灰色关联识别模型,从时空角度分析旅游活动对杭州湾北岸滨海人工浴场水环境的影响,研究滨海旅游活动与海水环境质量的关系。研究表明,滨海人工浴场由于管理模式及水体净化技术的不同,水域环境呈现不同的时空分布特征,但总体上滨海人工浴场建设和环境管理工作,可以有效保护滨海人工浴场以及周边区域水环境;不同旅游活动对水环境的影响程度不一,根据灰色关联识别模型综合评价指数,影响最大的是以水上自行车、皮划艇等为主的水上游乐项目,综合评价指数为2.571和2.542;其次是海滨游泳活动,综合评价指数为2.513;影响最小的水上舞台活动和观海踏潮,综合评价指数分别为2.501和2.472。     

钦州湾春季水质营养状况分析与评价

根据2010年4月对钦州湾海域调查结果,分析并评价了该海域春季的营养状况。结果表明,表层海水中DIN和SiO₃-Si都为茅尾海钦江入海口含量较高,PO₄-P为茅尾海西南部沿岸增养殖区含量较高,DIN、PO₄-P和SiO₃-Si水平分布上均表现为湾内含量高于湾外。从营养结构看,与Justic等提出的营养盐化学计量限制标准比较,符合P限制条件,PO₄-P可能成为浮游植物生长的潜在限制因子。根据营养状态指数评价模式和有机污染评价指数计算结果显示,2010年春季钦州湾海域营养水平属于中营养水平,有机污染程度属4级,表明钦州湾表层海水水质已达到中度污染。