Total mercury in marine species from the French coast of the Eastern English Channel

Mercury (Hg) in fish can present a potential risk to wildlife and human consumers. Mercury levels were determined in 12 fish species and 2 invertebrate species from the French coast of the Eastern English Channel collected in June and November 2012. Total mercury concentrations in the muscle tissues ranged between 0.04 and 1.63 µg g^-1 (d.w.). Dab and sandeel displayed a significant positive correlation between Hg concentrations and fish length. Seasonal differences in Hg concentrations were observed for dab and shrimp. The lesser weever showed significantly higher concentrations of Hg (0.97 ± 0.34 µg g^-1 d. w.) than all other species. Gobies and sprat, which had the smallest size, showed significantly lower concentrations than herring, whiting, pout and sardine. Among the considered species, flatfish such as dab, flounder, plaice and sole displayed intermediate levels of Hg. In the present study, the fish age expressed as specimen length seems to be one of the major factors governing Hg contents in muscle tissues. Finally, mercury concentrations in commercial fish from the Eastern English Channel were below the levels fixed by the European Union for total mercury in edible parts of fish products.     

Impact of trampling on sandy beach macrofauna

The effects of varying intensities of human trampling on sandy beach macrofauna were investigated at an exposed beach on the Eastern Cape coast. An experimental approach investigated the survival rates of four macrofaunal species which were subjected to human trampling at different intensities in a holiday-activity simulation. It was found that the clamDonax serra was slightly impacted at all trampling intensities whileDonax sordidus and the isopodEurydice longicomis were affected only at high trampling intensities. Vigorous beach games, such as volleyball, may have a damaging effect onD. serra. In a second experiment, the severe effects of human trampling onD. serra and the benthic mysidGastrosaccus psammodytes were investigated using numbered animals in enclosures. The results indicated that few members of the macrofauna were damaged at low trampling intensities but substantial damage occurred under intense trampling.     

Social trends of the people of the region of Eastern Macedonia and Thrace-Greece: about the potential of using biofuels from forest products residues

In the framework of enquiry of biomass usage possibilities in our country, a research was made through the whole Eastern Macedonia region, related to disposal possibilities from the production conveyors and usage possibilities from the region’s residents and businessmen, of biofuels that come from mechanical wood treatment residues and from the residues of agricultural production, in wooden form, known with the term wood pellets or wood briquettes. From the present study, it came to light that there is an intense interest for direct personal usage and application of biomass for the residents or occupational spaces heating. The necessary biomass quantity for the entire region’s households is estimated up to 205,520 t. From the biomass usage as a combustible material, a 680 €/year and household about, is made. The potential investments that will be made to the region seem to have a very short depreciation, but a business plan and a marketing plan syntax are considered as necessary for the result’s maximisation.     

区域分异视角下乡村企业入城意愿分析——基于浙、豫、川三省193家企业的实证研究

乡村企业入城是实现我国城镇化发展的基本路径。利用浙江、河南、四川三省193家乡村企业的实地调查数据,运用多元有序Logistic回归模型进行相关验证,实证分析我国东中西部三个省份的乡村企业入城意愿及其影响因素。通过对调研数据的描述统计发现:有58.55%的乡村企业主有入城意愿,仅有21.24%的乡村企业主不愿意或非常不愿意搬迁,集群环境、土地价格、运输成本等是企业愿意搬迁的主要原因,土地价格政策、当地经济发展水平、产品产销信息、集群环境是影响企业搬迁方向的重要因素,当地的土地、税收和融资等政府政策对于企业是否入城产生重要影响。通过多元有序Logistic回归模型估计结果表明:企业总资产、土地价格、运输成本、集群环境、与政府关系对入城意愿有显著负向影响,税收政策有显著正向影响,这些影响因素主要是通过影响企业的显性成本(土地价格、运输成本),以及企业的交易成本、寻租成本等隐性成本(集群环境、与政府关系和税收政策),进而影响企业的迁移意愿,且浙江、河南与四川三地计量结果差异显著。在上述研究的基础上,本文提出相应的政策建议。     

Specific features of the oribatid fauna in high-mountain pine forests of the Eastern Caucasus in relation to altitudinal zonality

The abundance, structure, and distribution of oribatid communities in high-mountain pine forest biotopes of the Eastern Caucasus are described in dependence on elevation above sea level. The oribatid fauna of high-mountain pine forests proved to be characterized by high abundance, an assortment of dominants, and species richness. It was shown that, as the elevation increases, specific dominants typical of particular altitudinal zones appear in communities, and changes in the mass species occur. These species are stable in terms of their long-term dynamics, and zonal groups (communities) demonstrate a high species diversity.     

Shipboard Measurements of Nitrogen Dioxide,Nitrous Acid,Nitric Acid and Ozone in the Eastern Mediterranean Sea

Measurements of nitrogen dioxide, nitrous and nitric acids as well as ozone were made using newly developed instrumentation onboard the research vessel Aegeon in the Aegean Sea between 25th–29th July 2000. Typical nitrogen dioxide concentrations observed aboard the boat were 4–6 ppb (v/v) with a broad maximum of 20–30 ppb (v/v). Ozone concentrations typically ranged between 40 and 80 ppb (v/v). Mixing ratios of both nitric and nitrous acids in the ambient air of the Aegean Sea were mainly below 50 ppt (v/v). The data also showed a number of short pollution episodes with rapid changes in the concentration of reactive nitrogen compounds [nitrogen dioxide maximum up to 164 ppb (v/v), nitric acid maximum up to 12 ppb (v/v), nitrous acid maximum up to 2.7 ppb (v/v)] and ozone [maximum up to 88 ppb (v/v)]. These episodes were correlated with pollution plumes originating from boats upwind, at short distance, from the R/V Aegeon. The measurements revealed the importance of nitrous and nitric acids for the transport of nitrogen to marine biota in busy ship lanes.     

Sediment and carbon accumulation in a small tidal basin: Yuehu,Shandong Peninsula,China

A small sedimentary basin (the Yuehu lagoon), located at the eastern tip of Shandong Peninsula, China, was selected to study its filling by sediment and the vertical flux of particulate organic carbon in response to natural/anthropogenic processes. Surficial and short core sediment samples were collected and analyzed to obtain data sets of grain size, organic carbon content, deposition rates and vertical fluxes of sediment and organic carbon. The analytical results show that the lagoon is covered mainly with fine-grained sediments with high deposition rate and particulate organic carbon content being found from the central part of the mud deposit. The sediment balance of the lagoon indicates high denudation rates of the catchment basin, which may be related to soil erosion in response to farming and land use pattern changes. Furthermore, preliminary analysis of the organic carbon fluxes of the Yuehu lagoon and other embayments of the region shows that these coastal systems make an important contribution to the regional shallow sea carbon burial.     

Distribution of Alkalinity, Ph, Salinity and Carbon Dioxide Components in the Coastal Waters of Alexandria

The ara studied is located between El-Dikheila Harbour in Elmex Bay and Mandara, at longitude 29° 47' and 30° East and latitude 31° 17' North. the aim of the work is to look at carbon dioxide components in this areA and the effect of waste water discharged on their concentrations. Surface and bottom water samples were collected from 12 stations during January, April, August and November, 1995. Total alkalinity, salinity, temperature and pH were measured. Carbonate alkalinity, total alkalinity, partial pressure and dissolved carbon dioxide, carbonate and bicarbonate ions were calculated, since the studied area includes two differetn sources of pollution. It wAs found conventient to refer El-Mex Bay as region “A” which contains stations from I to VI and the area located between Kayet Bey outfall and Mandara which contains stations from VII to XII as region “B”. When specific alkalinity is used As A tracer for El-Umum drain water it is observed that the drain water could reach Sidi Bishr area especially in August and November, while in January and April drain water did not reach this area.     

桂林市峰林平原区岩溶水文地球化学特征

峰林平原区往往作为岩溶地下水系统的主要径流、排泄地段且人类活动密集,其水文地球化学特征具有一定的独特性.对典型峰林平原区岩溶水文地球化学特征进行合理分析,不仅能够反应峰林平原区在丰水期的补给模式,而且也能够反应出人类活动对岩溶盆地中水化学组分的影响.通过对桂林市典型峰林平原区的补给区、内排泄区、补给径流区、排泄区岩溶地下水主要出露点和漓江上下游在丰水期与枯水期的野外取样、现场测试,对各化学指标进行空间和时间上的对比分析,结果表明:桂林市峰林平原区水文地球化学性质在丰水期与枯水期均呈现出明显的空间分布规律,且含水层介质岩性对地下水主要离子组分具有强烈的控制作用;丰水期的岩溶水文地球化学信息反应了在峰林平原区内排泄与补给径流区的补给模式以快速流为主,第四系土壤孔隙水垂向补给次之;桂林市峰林平原区人类活动对岩溶水化学性质具有一定的影响,主要为生活污染与农业污染,其重点防护区为内排泄区与补给径流区.     

崇明东滩表层沉积物重金属空间分布特征及其污染评价

以崇明东滩潮间带表层沉积物为研究对象,在粒度分析、重金属以及有机碳含量测定的基础上,采用ArcGIS中的地统计分析模块研究了重金属Cu、Pb、Zn、Cr、Cd的空间分布格局,应用克里金法进行空间插值作图,估算了沉降通量,并运用地质累积指数法和潜在生态危害指数法对重金属污染现状进行了评价.结果表明:①目前崇明东滩重金属Cu、Pb、Zn、Cr、Cd含量平均值分别为42、27、69、71、0.23μg.g-1,均超过上海潮滩背景值,且受沉积物粒径分布和有机碳的影响,重金属含量呈现自岸向海和自北向南下降的趋势;②崇明东滩重金属Cu、Pb、Zn、Cr、Cd的年沉降量分别为187、121、395、312、1.04 t,总沉积通量为11 g.(m2.a)-1,反映崇明东滩仍具有较强的重金属污染物"过滤器"功能;③重金属污染状况总体为清洁,但Cd、Pb和Cu的污染程度相对较高.