Narrowing down the number of species requiring detailed study as candidates for the EU Common Fisheries Policy discard ban

By 2019, the Common Fisheries Policy will prohibit discarding in all European fisheries of any pelagic, demersal or shellfish species for which removals are managed by TACs and quotas or minimum sizes. However, the regulation allows for exemptions from the prohibition for species for which scientific evidence demonstrates high survival rates associated with discarding. Producing reliable evidence of high survival typically requires long and costly studies involving tagging or captivity. This paper proposes to use the capacity to resist air exposure, a key stressor for discarded animals, as a proxy for survival that can be used to prioritize candidate species for more in-depth discard survival studies. The time required to induce mortality (TM) in air-exposed fish was estimated for ten discarded species under commercial fishing conditions for two artisanal French otter trawlers in the Bay of Biscay and in the English Channel. European seabass, plaice, sole and skates had extended TM values on average, suggesting that these species are good candidates. The three species observed in both regions (plaice, sole and skates) had larger TM values in the English Channel experiment compared to the Bay of Biscay experiment. Among the four measured external conditions that could influence TM (air temperature, fish length, tow depth and tow duration), the air temperature was the most important and the factor that most distinguished the two experiments.     

SEDIS IV型短周期自浮式海底地震仪数据校正方法

利用15台SEDISIV型短周期自浮式海底地震仪在南海中、北部地壳深部结构调查中所获得的资料,探讨了海底地震仪数据校正的方法和校正后的效果,结果表明:使用该地震仪所获得的原始资料经过放炮时间、炮点坐标数据局部化、海底地震仪位置误差以及记录时间漂移4方面的校正后,数据更趋合理,误差显著降低。放炮时间的校正消除了时钟漂移和时间延迟的误差;炮点坐标数据局部化处理消除了炮点位置整体趋势性偏移的现象;试错法进行位置误差和记录时间的精细校正时,时间漂移的校正量值约为几个到十几个毫秒,位置校正的量值仅在几米到数百米之间,实测数据所绘曲线的形态和位置都与理论曲线十分吻合,可见校正后误差显著降低。     

桦树沟铁铜矿床铜矿成矿地质条件及成矿模式浅析

桦树沟铁铜矿床铜矿体呈隐伏、半隐伏状态赋存于铁矿体下部,构成上铁下铜格局.铜矿的形成与海底火山喷气热泉活动关系密切,成矿物质既有正常沉积岩的特征又有火山源的特征,并经变质热液和岩浆热液改造使其进一步富集.     

Reducing Sb-leaching from municipal solid waste incinerator bottom ash by addition of sorbent minerals

This paper investigates the mechanisms controlling Sb-leaching from fresh Municipal Solid Waste Incinerator (MSWI) bottom ash, as well as the possibilities of controlling the extent of Sb-leaching by the addition of sorbent minerals to the bottom ash. In alkaline MSWI bottom ash Sb is possibly incorporated in ettringite-like minerals. When weathering/carbonation continues the ettringite dissolves resulting in a mobilisation of Sb. At neutral pH values the leaching of Sb is likely to be controlled by sorption to amorphous Fe/Al-(hydr)oxides. It has been shown that Sb can effectively be removed from solution if salts of Fe(III) or Al(III) are added to the bottom ash. This addition of Fe(III)/Al(III)-salts leads to (1) the in-situ precipitation of Fe/Al-hydroxides and sorption/coprecipitation of contaminants such as Sb, and (2) a lower bottom ash pH and thus an increased affinity of oxyanions for sorption to Fe/Al-(hydr)oxides.     

Zircon U-Pb Ages of Bottom and Top Parts of the Zhangjiakou Formation in Lingyuan Area （West Liaoning Province） and Luanping Area （North Hebei Province） and Their Significance

Thecharacteristicsofthetectonics,stratigraphy, paleontologyandvolcanicpetrologyoftheMesozoicin NorthHebeiandWestLiaoningaresimilarinmanyas pects,butthetworegionsalsohavesomeobvious differences.Thetworegionshavebeen“hotspots”inthegeologicalworldforafewy…     

西沙海槽研究区天然气水合物地球化学勘探

天然气水合物研究涵盖了地球物理、地球化学和地质等多门学科, 其中勘查地球化学方法技术可以从海底介质中获得与天然气水合物有关的痕量地球化学信息, 圈定水合物异常区域.依据2000年和2001年在中国南海西沙海槽工作区天然气水合物地球化学现场快速勘查实测和室内分析测试的多种烃类结果, 获得了海上工作区气态烃地球化学异常分布, 以及与该区水合物地震BSR和BZ的对比分析评价结果.同时根据现场实测同位素数据, 探讨了工作区形成水合物气态烃甲烷的成因.研究成果为工作区天然气水合物勘探提供了地球化学方面的直接证据.      

南华冰期的底界讨论:来自沉积学与同位素年代学证据

目前国内对于我国新元古代南华系划分的分歧很大,主要原因之一在于对板溪群及其相当层位地层的构造属性及其上限年龄的认识存在较大差异,为此,在详细的沉积学调查的基础上,对湘黔桂地区典型丹州群和下江群(与板溪群相当)有关剖面上顶部地层沉凝灰岩开展了锆石年代学研究.沉积学调查表明,板溪期沉积地层与上覆南华冰期沉积地层之间的转换界面清晰,界面上下岩性、结构、构造、沉积相特征迥异,显示板溪群和上覆南华纪冰期沉积期间存在明显的沉积—构造转换过程.而板溪晚期沉凝灰岩的锆石U-Pb同位素年代学研究则表明,板溪群及其相当层位的上限年龄均趋向于720 Ma,这与Sturtian冰期的启动年龄718 Ma接近.因此,基于沉积盆地演化的阶段性、全球性重要古气候演化的区域可对比性以及同位素年代学分析,将南华冰期启动年龄设定为720 Ma是恰当的,将我国南华系底界置于江口冰期沉积层系之底也是合理的,这为我国南华系底界GSSP的选定提供了重要的年代学和沉积学约束.     

丹江口水库土壤-底积物镉生态地球化学风险评价

湖北省十堰—丹江口地区多目标地球化学调查由中国地质科学院地球物理地球化学勘查研究所2013—2015年组织实施,旨在查明测区元素地球化学分布和分配特征,开展国土资源环境评价与基础地质研究,为国家及地方经济社会科学可持续发展提供基础资料.调查发现了丹江口水库底积物及沿汉江土壤镉富集现象.为保护丹江口水源地及南水北调水质安...     

基于光滑质点流体动力学的海冰热力-动力数值模式

考虑海冰热力因素对其厚度、密集度的影响,在光滑质点流体动力学(SPH)基础上发展了一个海冰热力-动力数值模式。该模式既解决了传统欧拉有限差分法和质点网格法存在的数值扩散问题,同时弥补了光滑质点动力学海冰动力模式未考虑热力因素的不足,具有精确模拟冰缘线运动、计算精度高等优点。首先介绍了光滑质点流体动力学的基本原理,并对海冰生消的热力因素进行了分析,将影响冰厚和密集度的热力因素引入到光滑质点流体动力学的海冰动力模式中,得到该热力-动力模式的控制方程。应用该数值模式对渤海海冰进行了48 h数值模拟,得到了海冰厚度和速度矢量的分布规律;对JZ20-2海域的海冰厚度、冰内温度场分布以及热力因素的变化特性进行了讨论。数值模拟结果表明,该数值模式能够很好地适用于渤海海冰数值模拟,是一种有效的海冰数值模拟方法。     

旋挖钻孔低粘降失水泥浆配制应用技术

在厚粘土、粉土、砂层进行旋挖钻孔灌注桩施工,通常由于泥浆孔口补给、泥浆不循环的工艺缺陷,导致塌孔、埋钻、卡钻、缩径、断桩事故频繁发生。在分析低粘、降失水、加速钻渣沉淀的解决机理的前提下,提出了配制低粘度、高降失水、防絮凝的铁铬盐-LV-CMC泥浆并同步孔底补浆工艺,可不需循环泥浆清孔,保证成孔质量,提高工作效率。