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81.
以台州(乐清湾)为例,研究了乐清湾海域生物体内多氯联苯(PCBs)的分布,其中以鱼、贝类和虾为主要实验对象,分析了多氯联苯的来源、浓度及各种影响因素。结果表明,鱼肉中∑PCBs 的残留含量为8.61~23.06ng/g,贝类中∑PCBs 的残留含量为11.77~38.04ng/g,对虾中∑PCBs的残留含量为0.38~11.19ng/g。近海生物体内多氯联苯的来源与当地工业排污、航运、PCBs废旧设施非法处置或封存不当等一系列因素有关。  相似文献   
82.
杨艳  潘铁山  江淼  徐静 《环境与发展》2020,(1):217-217,219
本文总结了江苏省省级环保引导资金整体情况、"因素法"切块分配方式的优点,在此基础上,剖析了省级环保引导资金管理中存在资金预算总额有待增加,省级层面缺乏支持手段、资金切块后地方管理能力愈趋不足,工作推进存在瓶颈、切块资金执行情况不佳,地方主动性有待提高等问题,有针对性地提出完善资金分配方式,力抓一批省级统筹分配项目、扩大省本级能力建设盘子,增加监控监测能力建设投入、厘清资金与项目管属关系,进一步明确资金管理职责等有关政策建议。  相似文献   
83.
Accumulation and distribution of uranium in roots and shoots of four plants species differing in their cation exchange capacity of roots (CECR) was investigated. After exposure in hydroponics for seven days to 100 μmol U L−1, distribution of uranium in roots was investigated through chemical extraction of roots. Higher U concentrations were measured in roots of dicots which showed a higher CECR than monocot species. Chemical extractions indicated that uranium is mostly located in the apoplasm of roots of monocots but that it is predominantly located in the symplasm of roots of dicots. Translocation of U to shoot was not significantly affected by the CECR or distribution of U between symplasm and apoplasm. Distribution of uranium in roots was investigated through chemical extraction of roots for all species. Additionally, longitudinal and radial distribution of U in roots of maize and Indian mustard, respectively showing the lowest and the highest translocation, was studied following X-ray fluorescence (XRF) analysis of specific root sections. Chemical analysis and XRF analysis of roots of maize and Indian mustard clearly indicated a higher longitudinal and radial transport of uranium in roots of Indian mustard than in roots of maize, where uranium mostly accumulated in root tips. These results showed that even if CECR could partly explain U accumulation in roots, other mechanisms like radial and longitudinal transport are implied in the translocation of U to the shoot.  相似文献   
84.
Total mercury concentrations in different tissues of frigate tuna fish (Auxis thazard thazard) was determined by the cold vapour atomic absorption spectrometry technique using an automatic mercury analyzer. A mixture of HNO3, HClO4 and H2SO4 was used for complete oxidation of organic tissue. The concentration of mercury obtained was in the order Gills < Stomach < Gonads < Intestine < Heart < Duodenum < Liver < Muscle. The concentration of total mercury detected in the edible muscle tissue of the tuna fish tested ranged from 0.044 to 0.201 μg g−1 (mean = 0.108 μg g−1) wet weight. These levels are all within the maximum allowed/recommended level in fish (0.5 μg g−1 wet weight) set by the Food and Agriculture Organisation/World Health Organisation (FAO/WHO) and are therefore unlikely to constitute any significant mercury exposure to the general population because of consumption of tuna fish. The results of the study suggest a relatively clean marine environment that has not been significantly impacted by mercury contamination probably due to minimal industrial activity in the region.  相似文献   
85.
Exxon Neftegas Limited, operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG), on behalf of the Sakhalin-1 consortium, conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary known feeding area of the endangered western gray whale (Eschrichtius robustus) is located adjacent to the seismic block. The data presented here were collected as part of daily monitoring to determine if there was any measurable effect of the seismic survey on the distribution and abundance of western gray whales. Mitigation and monitoring program included aerial surveys conducted between 19 July and 19 November using the methodology outlined by the Southern California High Energy Seismic Survey team (HESS). These surveys provided documentation of the distribution, abundance and bottom feeding activity of western gray whales in relation to seismic survey sounds. From an operations perspective, the aerial surveys provided near real-time data on the location of whales in and outside the feeding area, and documented whether whales were displaced out of an area normally used as feeding habitat. The objectives of this study were to assess (a) temporal changes in the distribution and abundance of gray whales in relation to seismic survey, and (b) the influence of seismic survey, environmental factors, and other variables on the distribution and abundance of gray whales within their preferred feeding area adjacent to Piltun Bay. Multiple regression analysis revealed a limited redistribution of gray whales southward within the Piltun feeding area when the seismic survey was fully operational. A total of five environmental and other variables unrelated to seismic survey (date and proxies of depth, sea state and visibility) and one seismic survey-related variable (seg3d, i.e., received sound energy accumulated over 3 days) had statistically significant effects on the distribution and abundance of gray whales. The distribution of two to four gray whales observed on the surface (i.e., about five to ten whales in total) has likely been affected by the seismic survey. However, the total number of gray whales observed within the Piltun feeding area remained stable during the seismic survey. M. W. Newcomer, Deceased.  相似文献   
86.
2006年秋冬两季图们市大气气溶胶中多环芳烃分布规律   总被引:1,自引:0,他引:1  
大气气溶胶是目前大多数城市的首要污染物,其中的多环芳烃是对人体健康危害最大的环境污染物之一。通过图们市2006年9月、12月4个采样点的大气气溶胶样品分析,研究了大气气溶胶中多环芳烃的分布规律。采用超声波萃取法提取样品中的多环芳烃,然后对其进行旋蒸浓缩,氮气吹至1ml,用高效液相色谱进行定性和定量分析。实验结果表明,美国EPA优先控制的16种多环芳烃普遍存在于图们市区的大气气溶胶中。图们市不同时空大气气溶胶中多环芳烃的分布具有一定的规律性。  相似文献   
87.
浙江北部海域春季浮游动物的群落结构研究   总被引:2,自引:0,他引:2  
根据2007年春季在浙江北部海域所采集的浮游动物样品,对该调查海域浮游动物的种类组成、丰度、生物量和生物多样性进行了探讨,采用多元统计软件PRIMER 5分析了该海域浮游动物的群落结构。研究结果表明,调查海域共鉴定各类浮游动物62种、浮游幼虫12种,合计74种。经统计共有2种优势种,分别是中华哲水蚤(Calanus sinicus)和五角水母(Muggiaea atlantica)。浮游动物生物量和丰度的平面分布比较相似,主要分布在调查海域的东部和东南部,并存在着向东南方向呈递增的趋势,而在杭州湾内的值比较小。调查海域浮游动物生物多样性比较低,平均值为1.54。根据对本次调查获得的浮游动物群落结构的聚类分析,主要存在着两个生态类群,群落Ⅰ为沿岸低盐群落,群落Ⅱ为暖温带近海群落。  相似文献   
88.
图们市大气颗粒物中重金属含量及分布特征   总被引:4,自引:2,他引:2  
采集了图们市2006年秋、冬两季的TSP和PM10样品,采用湿法消解-原子吸收分光光度法测定了其中的铅、镉、饲、锌、铬、铁、锰7种重金属.结果表明,图们市大气颗粒物中重金属含量由高到低的顺序是Fe>Cr>Zn>Pb>Mn>Cu>Cd.多数重金属元素含量冬季高于秋季,在一天之内早晨的重金属浓度也往往高于晚上争中午,说明大气颗粒物的来源包括天然源和人为源.  相似文献   
89.
为了解华东某市老城区潜层地下水硝酸盐分布特征,对老城区地下水现场采样,运用统计学软件spss中的Pearson相关系数和sufer软件Kriging插值方法分析数据,研究了无机氮与地球化学因素间的相关性,同时绘制了p H值、总硬度、硝酸盐、亚硝酸盐的空间分布图。结果表明,硝酸盐是该地区地下水中无机氮的主要存在形态,其所占总氮含量为45.5%~74.8%,封口井的硝酸盐的含量明显低于敞口井的含量,其硝酸盐所占比例最低达到2.2%,且敞口井均受到污染;从相关性的角度来看,氮的转化受到Fe影响较弱。同时氮的形态与p H值、矿化度(TDS)、电导率(EC)等地球化学因素相关水平显著;从分布特征来看,地下水环境中硝酸盐和亚硝酸盐含量东北部高于西南部;不同形态氮的相互转化影响地下水p H值和总硬度,致使p H值的高值区为西南部,而总硬度高值区为东北部。  相似文献   
90.
Concentrations, spatial distribution and sources of 17 polycyclic aromatic hydrocarbons (PAHs) and methylnaphthalene were investigated in surface sediments of rivers and an estuary in Shanghai, China. Total PAH concentrations, excluding perylene, ranged from 107 to 1707 ng/g-dw. Sedimentary PAH concentrations of the Huangpu River were higher than those of the Yangtze Estuary. The concentration of the Suzhou River was close to the average concentration of the Huangpu River. PAHs source analysis suggested that, in the Yangtze Estuary, PAHs at locations far away from cities were mainly from petrogenic sources. At other locations, both petrogenic and pyrogenic inputs were significant. In the Huangpu and Suzhou Rivers, pyrogenic input outweighed other sources. The pyrogenic PAHs in the upper reaches of the Huangpu River were mainly from the incomplete combustion of grass, wood and coal, and those in the middle and lower reaches were from vehicle and vessel exhaust.  相似文献   
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