A song of volumes,surfaces and fluxes: The case study of the Central Mallorca Depression (Balearic Promontory) during the Messinian Salinity Crisis

The Central Mallorca Depression (CMD) located in the Balearic Promontory (Western Mediterranean) contains a well-preserved evaporitic sequence belonging to the Messinian Salinity Crisis (MSC) salt giant, densely covered by high- and low-resolution seismic reflection data. It has been proposed recently that the MSC evaporitic sequence in the CMD could be a non-deformed analogue of the key MSC area represented by the Caltanissetta Basin in Sicily. This presumed similarity makes the CMD an interesting system to better understand the MSC events. Physics-based box models of the water mixing between sub-basins, built on conservation of mass of water and salt, help constrain the hydrological conditions under which evaporites formed during the MSC. Those models have been widely used in the literature of the MSC in the past two decades. They have been mostly applied to the Mediterranean Sea as a whole focusing on the Mediterranean–Atlantic connection, or focusing on the influence of the Sicily Sill connecting the Western and Eastern Mediterranean Sea. In this study, we apply a downscaled version of such modelling technique to the CMD. First, we quantify the present-day volumes of the MSC units. We then use a reconstructed pre-MSC paleo-bathymetry to model salinity changes as a function of flux exchanges between the CMD and the Mediterranean. We show that a persistent connection between the CMD and the Mediterranean brine near gypsum saturation can explain volume of Primary Lower Gypsum under a sea level similar to the present. For the halite, on the contrary, we show that the observed halite volume cannot be deposited from a connected CMD-Mediterranean scenario, suggesting a drawdown of at least 850 m (sill depth) is necessary. Comparison between the deep basin halite volume and that of the CMD shows that it is possible to obtain the observed halite volume in both basins from a disconnected Mediterranean basin undergoing drawdown, although determining the average salinity of the Western Mediterranean basin at the onset of drawdown requires further investigation.     

盐度和pH对合浦珠母贝（Pinctada fucata）耗氧率和排氨率的影响

采用实验生态学方法,对3种规格的合浦珠母贝在不同盐度和pH下的耗氧率和排氨率进行了研究。结果表明,盐度对合浦珠母贝的耗氧率和排氨率有极显著影响（P〈0．01）。在盐度21—36的范围内,耗氧率和排氨率均随盐度的升高而降低,且单位体重耗氧率、排氨率随其个体的增大而变小;pH对合浦珠母贝的耗氧率有极显著影响（P〈0．01）...     

Study of a Neogene basin dynamics: The “Bizerte basin”, northeastern Tunisia: relevance to the global Messinian Salinity Crisis

The Messinian sediments of northeastern Tunisia were deposited under an active tectonic setting. They are organized in sequences indicating a transitional deposit from margin – littoral to lacustrine – continental facies. These series unconformably overlie the Serravallian–Tortonian silty clays packages, and are overlain by the transgressive Early Pliocene marl (Zanclean). The presence of evaporitic strata points out to the Messinian Salinity Crisis described in the peripheral basins of the western Mediterranean. The Messinian sedimentation was found to have been closely controlled by transtensive tectonics and differential subsidence at a large spatio-temporal scale. It is organized in sequences typical of a depositional environment controlled by eustatism, tectonic and maybe by climate changes. Despite the existence of some local specific sedimentological characteristics, our results corroborate previous findings that pointed out to the Messinian times as a singular period all around the Mediterranean Basin. Field and subsurface seismic profile data helped reconstructing either the sedimentary or tectonic unconformities existing between the studied Messinian series and older Neogene successions.     

CO2/CaCl2 solution interfacial tensions under CO2 geological storage conditions: Influence of cation valence on interfacial tension

The effectiveness of CO₂ storage in deep saline aquifers and hydrocarbon reservoirs is governed, among other factors, by the interfacial tension between the injected CO₂ and formation water (brine). Experimental data on CO₂/water and CO₂/NaCl solution have revealed that the interfacial tension depends on the pressure, temperature and water salinity. However, there is still a lack of data for other salts (such as MgCl₂ and CaCl₂) which are also present in aquifers and carbonate reservoirs.     

The end of the Messinian Salinity Crisis in the western Mediterranean: Insights from the carbonate platforms of south-eastern Spain

How the Messinian Salinity Crisis (MSC) ended is still a matter of intense debate. The Terminal Carbonate Complex (TCC) is a late Messinian carbonate platform system that recorded western Mediterranean hydrological changes from the final stages of evaporite deposition till the advent of Lago-Mare fresh- to brackish water conditions at the very end of Messinian times. A multidisciplinary study has been carried out in three localities in south-eastern Spain to reconstruct the history of TCC platforms and elucidate their significance in the MSC. Overall, this study provides evidence that the TCC formed following a regional 4th order water level rise and fall concomitant with an opening-restriction trend. It can be subdivided into four 5th order depositional sequences (DS1 to DS4) recording two phases: (1) from DS1 to DS3, a tide-dominated ooidic to oobioclastic system with stenohaline faunas developed as a result of a 70 m water level rise. During this period, the TCC developed in a shallow sea with close to normal marine salinity; (2) in depositional sequence 4, a microbialite-dominated platform system developed. This is indicative of a significant environmental change and is attributed to a 30 to 40 m water level fall in the basins under study. These restricted conditions were coeval with intense evaporite deformation and brine recycling. The syn-sedimentary deformation of evaporites had a major impact on platform architecture and carbonate production, affecting the Messinian series throughout south-eastern Spain at the end of the TCC history. At that time, the TCC developed in a lake with fluctuating, brackish- to hypersaline water. These findings suggest a temporary restoration of marine conditions in the western Mediterranean marginal basins due to Atlantic water influxes prompted by a global sea level rise around 5.6 Ma. Whether marine conditions extended to the entire western Mediterranean still needs to be investigated.     

胶州湾气象水文要素的长期变化

利用线性回归方法对胶州湾1898—2008年气温和降水、1962—2008年的水温和盐度四个气象水文要素的长期变化规律进行了分析。结果表明,百年来胶州湾地区气温的变化呈现波动上升趋势。从1920年前后到1950年的30年间,年平均气温的年变率为0.028℃,从20世纪60年代起至今,年平均气温的年变率为0.031℃。升...     

Comparison of selected biomarkers in flounder (Platichthys flesus L.) from the Douro (Portugal) and Vistula (Poland) River estuaries

Sixty female flounder (Platichthys flesus) were collected in Autumn 2011, 15 from each of the following sampling sites: at the mouths of the Douro and Vistula Rivers, and at nearby open sea locations. The aim of the study was to assess several biomarkers in the two geographically distant regions. Hepatic EROD, GST, SOD, GPx, POx, LP; muscular AChE, BChE, LP; and branchial Na⁺/K⁺-ATPase were analysed. Moreover, BTI, PY, and three gross morphometric indices were calculated. The results were analysed with t-test, ANOVA, and PCA. Many differences were found between the open sea sites and the river mouths, mainly in Portugal, and between the two rivers. Salinity and pollution seem to be the main factors that affected the biomarkers. Effects of chronic pollution were observed at the river mouths, and an indication of a possible temporary exposure to pollutants was found at the open ocean site in Portugal.     

大黄鱼库道虫病的初步研究

在广东湛江海水网箱养殖的大黄鱼 (Pseudosciaenacrocea)中发现了库道虫病 (Kudoasis) ,检出率高达 31%。其症状表现为 :白色孢囊分布于胸鳍、腹鳍、臀鳍和尾鳍等的鳍膜下 ,剖检时发现腹壁和背部肌肉中布满许多白色呈球形或椭圆形的小孢囊 ,在肠系膜、腹膜以及近口腔的粘膜上也有大量的白色小孢囊分布。镜检发现孢囊中含有典型的库道虫 ,其孢子宽为 ( 8 90± 0 55) μm ,长为 ( 8 35± 0 4 6 ) μm ,极囊宽为 ( 2 39± 0 36 ) μm ,极囊长为 ( 4 4 8± 0 39) μm。孢子在淡水中 2 0min后全部死亡 ,在盐度为 6的水体中 ,12h和 2 4h后存活率分别约为 87.4 %和 70 % ;在盐度为 16、2 6和 36的水体中 ,孢子存活率均为 10 0 % ;在盐度为 4 6的水体中 ,12h和 2 4h后存活率分别约为92 %和 84 %。孢子对低温有较强的耐受力 ,当水温达到 4 4℃时 ,8h、12h和 2 4h后 ,孢子的存活率分别约为 91%、80 .5%和 6 6 %。     

混合溶液浓度线性图解法及其在水产养殖中的应用

提出一种关于同质溶液混合的浓度或溶液量任意项求解的线性图解法，并阐明其在水产养殖的换水水质控制和盐度调节方面的应用。     

Phytoplankton community structure defined by key environmental variables in Tagus estuary, Portugal

In this work, we analyze environmental (physical and chemical) and biological (phytoplankton) data obtained along Tagus estuary during three surveys, carried out in productive period (May/June/July) at ebb tide. The main objective of this study was to identify the key environmental factors affecting phytoplankton structure in the estuary. BIOENV analysis revealed that, in study period, temperature, salinity, silicate and total phosphorus were the variables that best explained the phytoplankton spatial pattern in the estuary (Spearman correlation, rho=0.803). A generalized linear model (GLM) also identified salinity, silicate and phosphate as having a high explanatory power (63%) of phytoplankton abundance. These selected nutrients appear to be consistent with the requirements of the dominant phytoplankton group, Baccilariophyceae. Apparently, phytoplankton community is adapted to fluctuations in light intensity, as suspended particulate matter did not come out as a key factor in shaping phytoplankton structure along Tagus estuary.