现代浮游有孔虫对南海西南部上升流的响应

现代夏季风系统导致了南海西南部（越南岸外）上升流的发育,但浮游有孔虫对夏季上升流的响应如何尚缺乏实测资料,这不利于准确地利用有孔虫来重建古上升流的活动进而反演过去夏季风的强度变化。本研究利用2014年4月14日至11月1日布放于南海西南部夏季上升流区的时间序列沉积物捕获器材料,详细鉴定并定量统计了其所含浮游有孔虫类型。通过分析样品中浮游有孔虫各属种的通量和百分含量变化,结合区域气候环境资料,探讨南海西南部夏季上升流区浮游有孔虫对夏季风的响应,为古上升流与夏季风研究提供现代依据。研究结果表明初级生产力是控制上升流区浮游有孔虫通量变化的首要因素,喜营养种在上升流发育期增多而寡营养种含量下降。因此高表层生产力指示种,如Neogloboquadrina dutertrei可能是追溯南海西南部夏季上升流变化最可靠的指标。

     

Integration of reflection seismic and sediment grain-size data from Lake Khubsugul (Northern Mongolia): a reply to Prokopenko and Kendall

Prokopenko and Kendall (J Paleolimnol doi:, 2008) criticise the work presented in Fedotov et al. (J Paleolimnol 39:335–348, 2008), and instead propose an alternative interpretation for the grain-size evolution recorded in the KDP-01 core, retrieved from the central part of Lake Khubsugul. Their interpretation is based (i) on a seismic-stratigraphic re-interpretation of sparker seismic profile khub012 (which they copied from Fedotov et al. (EOS Trans 87:246–250, 2006)), (ii) on the presupposition that changes in lake level are the dominant control on facies distribution in Lake Khubsugul, and (iii) on the invalidation of our age-depth model. In this reply to their comment, we demonstrate that they interpreted seismic artefacts and geometries caused by changes in profile orientation as true stratigraphic features and that the lake-level reconstruction they derive from this interpretation is therefore incorrect. We also demonstrate that their grain-size predictions, which they consider to be predominantly driven by changes in lake level, are inconsistent with the measured sulphate concentration, which is a demonstrated proxy of lake level in Lake Khubsugul, and with the measured grain-size record. Finally, we point out that even if there would be a problem with the age-depth model, this problem would not affect the part of the sedimentary sequence discussed in Fedotov et al. (J Paleolimnol 39:335–348, 2008).     

Artificial light at night: implications for early life stages development in four temperate freshwater fish species

Flora and fauna have both evolved under a natural cycle of light and dark. But especially in urban areas, the night is now increasingly disturbed by artificial light. Many traits and behaviours in fish are triggered by a circadian clock, for example hatching and swim bladder inflation, which predominantly take place at dusk or night. As lighting becomes brighter and extends farther into rural areas, the distinction between day and night becomes increasingly blurred. Therefore, the loss of diurnal trigger by artificial light at night was hypothesized having deleterious effects on these traits and impact fish reproduction. To assess these effects, eggs of four native freshwater fishes, Eurasian perch Perca fluviatilis, roach Rutilus rutilus, bleak Alburnus alburnus and chub Leuciscus cephalus, were incubated under two different light conditions: a photoperiod of 14 h light:10 h darkness (LD) and continuous illumination (LL). The time to hatch and swim bladder inflation was recorded. The species showed inconsistent reactions to the light treatments. In roach and bleak, the time to 50% hatch was longer in LL, whereas continuous lighting had an accelerating effect in chub. Incubation in LL elongated the hatching period in perch and roach and, in perch, the onset of darkness seemed to trigger hatching. The swim bladder inflation was significantly promoted by continuous light in chub and bleak but was not affected in roach. In conclusion, nocturnal artificial illumination could have an effect on hatching and initial swim bladder filling by masking the day–night-change and thereby diminish the trigger effect. However, the reactions were species specific and the increase in variation indicated a lack of diurnal triggering, whilst a general deleterious effect of artificial light at night has not been identified on early life stages.     

南黄海夏末叶绿素a的分布特征

根据1995年9月利用日本《神鹰丸》号调查船在黄海32°00'–35°00'N,122°00'–127°00'E海区的19个站位上进行的中日联合调查研究中叶绿素a含量的调查资料,探讨南黄海海区夏末初叶绿素a含量的变化、平面分布、断面分布和垂直分布状况,以及与海域环境因子之间的关系。在每个测站上作垂直取样,表层水用圆塑料桶取自海表面,深层水用日本提供的专用采水器采集,取出水样立即量取200ml,用玻璃纤维滤膜过滤浓缩,并加入2％的饱和碳酸镁溶液,防止叶绿素脱镁,然后保存在冰箱内（-1°C）,用冰桶带回实验室进行分析。将载有浮游植物的滤膜放入闪烁瓶内加入10ml 90％的丙酮溶液,在冰箱内提取24h。用萃取荧光法测定叶绿素a含量。结果表明,该海域的叶绿素a含量较高,平均值为1.14mg／m³,其变化范围为0.10–7.76mg／m³,最高值在次表层。（1）平面分布:各层次平面分布特征差异较大。33°00'–33°30'N之间叶绿素a含量均较低,低于0.50mg／m³。33°30'N以北,叶绿素a含量低于0.20mg／m³,而33°00'N以南,除济州岛附近的17–19导站以外,叶绿素a含量均较高,高于100mg／m³。（2）断面分布:水深在30m时,叶绿素a含量的高值区在20m以上水体的次表层中,而水深为50–80m时,其高值分布在20–40m的次表层中。（3）叶绿素a的垂直分布也体现了断面分布的特征。所以作者认为,光是浮游植物生长和繁殖的重要因子之一。     

A study on sample pretreatment of analysis of Cd, Pb and Zn in seawater by IDMS

Isotope dilution mass spectrometry (IDMS) and ultra-clean room approach are successfully used in the determination of Cd, Pb and Zn in seawater and the sample pretreatment of analysis. The precision in the determination of Cd, Pb and Zn in seawater is better than±3% and the limits of detection are 6×10-12, 6×10-11 and 2.4×10-10 respectively. The effects of sample pretreatment such as filtration and acidification on the results of determination of Cd- Pb and Zn in seawater are disscussed.     

PolarGlobe: A web-wide virtual globe system for visualizing multidimensional,time-varying,big climate data

The increasing research interest in global climate change and the rise of the public awareness have generated a significant demand for new tools to support effective visualization of big climate data in a cyber environment such that anyone from any location with an Internet connection and a web browser can easily view and comprehend the data. In response to the demand, this paper introduces a new web-based platform for visualizing multidimensional, time-varying climate data on a virtual globe. The web-based platform is built upon a virtual globe system Cesium, which is open-source, highly extendable and capable of being easily integrated into a web environment. The emerging WebGL technique is adapted to support interactive rendering of 3D graphics with hardware graphics acceleration. To address the challenges of transmitting and visualizing voluminous, complex climate data over the Internet to support real-time visualization, we develop a stream encoding and transmission strategy based on video-compression techniques. This strategy allows dynamic provision of scientific data in different precisions to balance the needs for scientific analysis and visualization cost. Approaches to represent, encode and decode processed data are also introduced in detail to show the operational workflow. Finally, we conduct several experiments to demonstrate the performance of the proposed strategy under different network conditions. A prototype, PolarGlobe, has been developed to visualize climate data in the Arctic regions from multiple angles.     

海水声速剖面基函数的重构性能分析

海水声速剖面通常使用经验正交函数（Empirical Orthogonal Function,EOF）进行稀疏表示,然而基函数会受到数据完备性和数据测量时间的制约,其代表性误差会导致声速剖面重构精度受限。为了提高声速剖面的重构精度,本文利用模糊C均值聚类对BOA_Argo历史数据集进行聚类分析,探讨不同聚类空间的训练集数据对实测声速剖面重构精度的影响。研究表明,声速剖面具有明显的时空聚集特性,聚类后的历史声速剖面集生成的基函数和平均声速剖面具有最优的重构性能。本文研究结果有助于为历史声速剖面训练集的选取提供实际指导意义,进而提高声速剖面重构精度乃至反演精度。     

山东省肥城断块岩溶水系统地下水水化学特征及演化分析

地下水是肥城地区最主要的供水水源,近年来受到工农业生产、煤矿开采、闭坑、矿井排水等人类活动影响,肥城地区地下水动力场及化学场都发生了变化,为查明地下水的环境质量状况,文章在研究水文地质调查和样品采集分析基础上,综合运用数理统计方法、水化学方法（Piper三线图、Gibbs模型、矿物饱和指数、离子比例分析）等,探讨肥城断块地下水水化学特征及演化规律。结果表明：（1）研究区地下水均呈弱碱性,$ {\mathrm{C}\mathrm{a}}^{2+} $、$ {\mathrm{M}\mathrm{g}}^{2+} $、$ {{\mathrm{H}\mathrm{C}\mathrm{O}}_{3}}^{-} $和$ {\mathrm{S}\mathrm{O}}_{4}^{2-} $为主要离子,主要来源于方解石、白云石及石膏溶解;矿物饱和指数表明方解石和白云石绝大多数处于饱和状态,石膏和岩盐矿物呈溶解未饱和状态。（2）区内岩溶水化学类型主要为$ {\mathrm{H}\mathrm{C}\mathrm{O}}_{3}-\mathrm{C}\mathrm{a}\left(\mathrm{M}\mathrm{g}\right) $型,其次为$ {\mathrm{H}\mathrm{C}\mathrm{O}}_{3}·{\mathrm{S}\mathrm{O}}_{4}-\mathrm{C}\mathrm{a} $型和$ {\mathrm{H}\mathrm{C}\mathrm{O}}_{3}·\mathrm{C}\mathrm{l}-\mathrm{C}\mathrm{a} $型。孔隙水主要为$ {\mathrm{S}\mathrm{O}}_{4}·{\mathrm{H}\mathrm{C}\mathrm{O}}_{3}-\mathrm{C}\mathrm{a} $型、局部出现$ {\mathrm{S}\mathrm{O}}_{4}{·\mathrm{N}\mathrm{O}}_{3}-\mathrm{C}\mathrm{a} $型。河流水化学类型相对复杂,包括$ {\mathrm{S}\mathrm{O}}_{4}·{\mathrm{H}\mathrm{C}\mathrm{O}}_{3}-\mathrm{C}\mathrm{a}·\mathrm{N}\mathrm{a} $型、$ \mathrm{C}\mathrm{l}·{\mathrm{S}\mathrm{O}}_{4}-\mathrm{C}\mathrm{a}·\mathrm{N}\mathrm{a} $型等。（3）区内地下水中$ {\mathrm{C}\mathrm{l}}^{-} $、$ {\mathrm{S}\mathrm{O}}_{4}^{2-} $和$ {\mathrm{N}\mathrm{O}}_{3}^{-} $含量相比1999年、2013年显著升高。裂隙水及岩溶水水质整体较好,局部呈点状变差,孔隙水及河水水质普遍较差,影响区域地下水水质的主要因素有化肥施用、禽畜养殖、生活污水下渗以及煤矿排水等。     

The Upper Middle Rhine Valley as a risk area

The Upper Middle Rhine Valley, granted the status of a World Heritage site, is well known for its unique inner narrow valley of Quaternary age with its historical legacy of numerous medieval castles and old towns. Less known is that this has always been a risk area of floods and gravitative mass movements. Up to the recent past, mainly ice floods caused enormous damage. The inhabitants of the valley were well aware that they lived in a risk area, but they had learned to handle the flood hazard. With the demise of ice floods over the last 40 years, due to climate change and because of the additional heating of the river water by power plants, the awareness of flood hazards has been much diminished, in contrast to that of potential damage by rockfalls and landslides which were also much feared in the past, though at the local level only. Still in the people’s memory is the Kaub catastrophe of March 10, 1876, when 28 persons were killed by a landslide. Nowadays, even minor rockfalls are a major threat, as they will affect the much-used traffic lines on both banks of the river, in particular the railroads. Therefore, since 2002, on behalf of German Rail (Deutsche Bahn, DB), all problematic slopes have been protected by costly steel-ring nets, although they are an aesthetic problem by UNESCO standards. The feeling of absolute safety created among the public is only subjective, though, as planners are well aware of. Moreover, the impact of modern climate change on slope stability is nearly unknown. Therefore, it is still necessary to develop a risk map for the narrow valley, with emphasis on gravitational hazards.     

Temporal and spatial dynamical simulation of groundwater characteristics in Minqin Oasis

Application scope of geostatistics has been gradually extended from original geologic field to soil science and ecological field, etc. and its successful application results have been widely demonstrated. But little information is reported as to the direct use of geostatistical method to work out the distribu- tion map of groundwater characteristics. In this paper the semivariogram of geostatistics, in combina- tion with GIS, was used to quantitatively study the spatial variation characteristics of groundwater table depth and mineralization degree and their relation to the landuse changes. F test of the used spherical model reached a very significant level, and the theoretical model can well reflect the spatial structural characteristics of groundwater table depth and mineralization degree and achieve an ideal result. This shows that the application of the method in the dynamical simulation of groundwater is feasible. And this paper also provides useful reference for the application of geostatistics in the study of the dy- namical variations of groundwater resources in the oasis.