The role of burrowing beds and burrows of the SW Atlantic intertidal crab Chasmagnathus granulata in trapping organochlorine pesticides

The effect of crab beds and bioturbation activity of the SW Atlantic intertidal crab Chasmagnathus granulata on the organochlorine pesticide (OCP) concentrations in Bahía Blanca estuary, Argentina were studied. Total OCP concentration was significantly lower inside than outside the crab burrows. Nevertheless, the concentrations from outside the crab beds were lower than from outside crab burrows, which indicated that crab beds act as sinks of sediment-bound OCP due to the bioturbation activities of the crabs. The same distribution patterns were found in all sediments as well as in crabs, being cyclodienes>HCHs>DDTs, although large amounts of metabolites rather than the respective parental were found in the organism showing the capacity of C. granulata for metabolising parental compounds. These more water-soluble compounds are excreted by the faeces and finally removed by tidal flushing to the sea. Our results suggest that crabs when present play a role in the distribution of sediment-bound OCP and the crab beds are modifiers of the dynamic of organic pollutants in estuarine areas.     

Organochlorine contaminant exposure and associations with hematological and humoral immune functional assays with dam age as a factor in free-ranging northern fur seal pups (Callorhinus ursinus)

Potential effects of organochlorine contaminant (OC) exposure on humoral immune function and health of free-ranging northern fur seals were investigated. Forty-two "neonates" were captured for blood sample collection and re-sampled as "pups" 29-51 days later. OCs were extracted from whole blood to identify polychlorinated biphenyl congeners and chlorinated pesticides by high performance liquid chromatography. Humoral immune function was assessed by antibody responses to vaccination and immunoglobulin concentrations. Additional health status indicators included leukocyte counts and haptoglobin concentrations. Mean OC concentrations were higher in neonates than at recapture. Neonates of young dams had higher mean OC concentrations than neonates of older dams. A higher proportion of old dam's pups developed a twofold or greater increase in antigen-specific antibodies compared to young dam's pups. Higher OC exposure and poor immune responses in first-born pups may indicate a higher risk of secondary morbidity and mortality than pups of multiparous dams.     

Eelpout (Zoarces viviparus) in marine environmental monitoring

The implementation of the EU Marine Strategy Framework Directive necessitates the development of common criteria and methodological standards for marine environmental monitoring and assessment across Europe. Eelpout (Zoarces viviparus) is proposed as a key indicator organism in the Baltic and North Sea regions. This benthic fish species is widely used in ecotoxicological studies and as a bioindicator of local pollution due to its stationary behavior. Eelpout is included in the environmental monitoring program of several Baltic States, covering both chemical and biological effects measurements, and samples have been archived in environmental specimen banks for >15 years. A method for evaluating the frequency of larval aberrations has been suggested as a standardized assessment tool. The large scientific knowledge-base and considerable experience of long-term chemical and biological effects monitoring and specimen banking, make eelpout a suitable species for the assessment of Good Environmental Status in the Baltic and North Seas.     

Impacts of maintenance dredged material disposal on macrobenthic structure and secondary productivity

The results of a monitoring programme to assess the spatial impacts associated with ongoing dredged material disposal activity at a dispersive, coastal disposal site (southwest UK) are described. Benthic impacts were assessed using benthic community structure and secondary productivity estimates.Analyses of univariate indices (including secondary production) and multivariate community structure revealed differences between stations inside and those outside the disposal site were minimal. Generally, stations within and outside the disposal site were characterised by the same species. Regression models indicated that the variability in biological structure and secondary production was predominantly accounted for by natural variables (e.g., depth, sediment granulometry) with only a small amount of residual variability being due to contaminant variables. Thus, the elevated levels of certain contaminants in the vicinity of the disposal area were not sufficient to result in significant ecological or ecotoxicological changes. We ascribe such findings partly to the dispersive nature of the disposal site.     

Accounting for density reduction and structural loss in standing dead trees: Implications for forest biomass and carbon stock estimates in the United States

Background  

Standing dead trees are one component of forest ecosystem dead wood carbon (C) pools, whose national stock is estimated by the U.S. as required by the United Nations Framework Convention on Climate Change. Historically, standing dead tree C has been estimated as a function of live tree growing stock volume in the U.S.'s National Greenhouse Gas Inventory. Initiated in 1998, the USDA Forest Service's Forest Inventory and Analysis program (responsible for compiling the Nation's forest C estimates) began consistent nationwide sampling of standing dead trees, which may now supplant previous purely model-based approaches to standing dead biomass and C stock estimation. A substantial hurdle to estimating standing dead tree biomass and C attributes is that traditional estimation procedures are based on merchantability paradigms that may not reflect density reductions or structural loss due to decomposition common in standing dead trees. The goal of this study was to incorporate standing dead tree adjustments into the current estimation procedures and assess how biomass and C stocks change at multiple spatial scales.     

工程设计招投标亟待杜绝以设计费为商务标的违法违规行为

目前,在煤炭工程勘察设计招投标工作中设置所谓商务标,即以投标人的勘察设计费报价高低作为评定能否中标的惟一标准或重要标准,这种违法违规行为是十分有害的。工程勘察设计招投标应执行国务院令规定的评标标准早在1986年6月25日,原国家计委发布的《关于加强工程设计招标投标工作的通知》就指出,"在招投标中不是择优评标,而是搞保护主义;有的招标     

摄影测量与遥感网格生产管理系统的设计与实现

在总结归纳摄影测量生产管理活动规律的基础上,采用本项目研究的信息化测绘生产管理技术成果,构建的摄影测量与遥感网格生产管理系统,支持数字摄影测量分布式生产作业平台无缝作业模式的快速搭建和整体运行,实现了信息化摄影测量与遥感生产管理模式。其通用性可移植到测绘其他专业信息化生产管理。     

游艇俱乐部运营机制与管理模式的优化研究——以三亚为例

游艇作为新型休闲旅游项目在中国迅速兴起。海南的游艇旅游在政策支持、资源环境等方面优势突出。三亚作为海南建设国际旅游岛的排头兵,对游艇旅游的发展给予了充分的重视。但游艇俱乐部在运营管理方面反映出的绩效不佳。通过回顾相关研究成果,并实际调查三亚游艇俱乐部的运营现状,重点对运营机制与管理模式进行剖析,归纳游艇俱乐部面临的发展难题,提出游艇俱乐部通过明确市场定位、创新业务类型、推动与关联行业融合发展、开辟营销公关新思路、完善投资机制等途径实现管理模式优化,进而使游艇俱乐部的内部管理适应环境变化。     

抗差Kriging方法在GPS高程拟合中的应用研究

由于环境或人为因素的影响,观测值中往往含有粗差,针对普通Kriging方法在GPS高程拟合中受粗差影响的问题,提出基于抗差估计的样本变异函数模型,以降低或消除粗差的干扰。利用实测数据对该算法进行试验分析,结果表明,利用改进的抗差变异函数模型处理含有异常值的观测样本,能有效地抵制异常值的影响,验证了抗差Kriging法在局部区域内进行高程拟合的可靠性和准确性。