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101.
缢蛏(Sinonovacula constricta)是我国重要的水产经济贝类,开展耐高盐新品种选育对平衡不同地区缢蛏良种养殖意义重大。本研究对不同家系缢蛏幼贝进行高盐胁迫,运用统计学方法和相关性分析探究了缢蛏耐高盐性能及其与生长性状的相关性。结果显示,缢蛏家系间壳长、壳高、壳宽和体质量表型值差异较大,体质量变异系数达15.53%。不同家系对高盐耐受性差异较大,家系间死亡率范围在0~100%。胁迫实验共持续9 d,各家系缢蛏首粒死亡时间在第1~9 d之间,而且死亡率较高的家系内缢蛏死亡时间离散程度较大,说明不同个体间高盐耐受性差异也较大。缢蛏开始出现大量死亡的时间主要在胁迫后第8 d,第9 d部分家系死亡率高于80%,说明缢蛏对高盐耐受存在一个阈值,超过该阈值会开始或大量死亡。皮尔逊和斯皮尔曼相关性分析显示,缢蛏存活时间和生长性状为正相关,其中存活时间与缢蛏壳长、体质量相关性均达到显著水平(P<0.05)。缢蛏存活率与体质量、生长速度均显著正相关(P<0.05)。整体而言,壳长较长和体质量较重的缢蛏个体耐高盐性能较强,在高盐环境中具有生长优势。本研究揭示了缢蛏的高盐耐受性及... 相似文献
102.
Ana P. Mucha C. Marisa R. Almeida Adriano A. Bordalo M. Teresa S.D. Vasconcelos 《Estuarine, Coastal and Shelf Science》2010
This work aimed to evaluate, in vitro, the capability of roots of two salt marsh plants to release low molecular weight organic acids (LMWOAs) and to ascertain whether Cu contamination would stimulate or not organic acids exudation. The sea rush Juncus maritimus and the sea-club rush Scirpus maritimus, both from the lower Douro river estuary (NW Portugal), were used. Plants were collected seasonally, four times a year in 2004, during low tide. After sampling, plant roots were washed for removal of adherent particles and immersed for 2 h in a solution that matched salinity (3) and pH (7.5) of the pore water from the same location to obtain plant exudates. In one of the seasons, similar experiments were carried out but spiking the solution with different amounts of Cu in order to embrace the range between 0 and 1600 nM. In the final solutions as well as in sediment pore water LMWOAs were determined by high performance liquid chromatography. Plants were able to release, in a short period of time, relatively high amounts of LMWOAs (oxalate, citrate, malate, malonate, and succinate). In the sediment pore water oxalate, succinate and acetate were also detected. Therefore, plant roots probably contributed to the presence of some of these organic compounds in pore water. Exudation differed between the plant species and also showed some seasonally variation, particularly for S. maritimus. The release of oxalate by J. maritimus increased with Cu increase in the media. However, exudation of the other LMWOAs did not seem to be stimulated by Cu contamination in the media. This fact is compatible with the existence of alternative internal mechanisms for Cu detoxification, as denoted by the fact that in media contaminated with Cu both plant species accumulated relatively high amounts (29–83%) of the initially dissolved Cu. This study expands our knowledge on the contribution of globally dominant salt marsh plants to the release of LMWOAs into the environment. 相似文献
103.
阿尔金山羌塘高原水资源开发及罗布泊钾盐矿建设的设想 总被引:1,自引:1,他引:0
《阿尔金山及羌塘高原水资源开发利用与保护考察报告》编写组 《干旱区地理》2007,30(6):785-790
阿尔金山水资源相对丰富,是巴音郭楞蒙古自治州河川径流的主要形成区之一,巴音郭楞蒙古自治州若羌县罗布泊镇钾盐贮量很大,经济效益可观,但水资源成为了罗布泊钾盐矿发展的限制性因素。能否把阿尔金山的水资源作为罗布泊钾盐矿发展的支撑,是我们必须回答的一个问题。本文利用新疆维吾尔自治区水利厅阿尔金山野外考察资料,分析阿尔金山的水系与湖泊、自然地理和社会经济特点,以期为探讨阿尔金山能否作为罗布泊钾盐矿开发的水源条件提供理论依据。 相似文献
104.
This study provides information on non-aromatic hydrocarbons contained in thick Palaeogene halite sequences in the Bresse region (France). The presence of almost uniquely biological markers and the absence of thermogenic compounds denote the low maturity of the corresponding samples consistent with Rock-Eval pyrolysis data. The distribution of n-alkanes enables the distinction of three main biological signatures: algal (mode in nC17–nC18); terrestrial (mode in nC29–nC31) and bacterial (mode in nC25–nC26 with no odd-even carbon number predominance). As to the cyclic biomarkers, hopanes and hopenes are largely predominant over steranes and diasterenes in samples having received appreciable amounts of terrestrial inputs (Type B) and conversely for the samples containing high proportions of algal debris (Type A, Type C). 相似文献
105.
106.
A. G. Taher S. Abdel Wahab G. Philip W. E. Krumbein A. M. Wali 《International Journal of Salt Lake Research》1995,4(2):95-116
A salina system along the Mediterranean coast of Egypt was investigated. Five sedimentary facies are described. For each facies, the evaporitic sedimentation and the biological conditions are considered. Comparisons of evaporite precipitates in the salina with ancient deposits are made. 相似文献
107.
通过蒙新高原典型盐湖区的解剖研究,查清了代表性盐湖盆地的相环境及其沉积建造,将盐湖盆地环境的变化形式划分为沉陷型、抬升型和改造型,并归结了盐湖盆地相环境分异与盆地地质结构之间的相互关系,为开发大陆干旱区盆地的盐湖和卤水资源及其环境演化的理论研究提供了依据。 相似文献
108.
盐风化是干旱区一种重要的岩石风化过程。本文初步研究了盐风化作用的性质、机制和强度及其在地貌塑造和生产实践上的意义。盐风化包括盐结晶风化作用和盐水化风化作用两种类型。盐风化的强度在很大程度上取决于盐类矿物性质和气候条件。高温和干旱相结合的气候最有利于盐风化过程。通过对未风化岩石和风化岩石的对比,证明盐风化发展的速率很高。Tafoni是盐风化发展阶段的一种重要标志。 相似文献
109.
新疆盐湖卤水水化学特征研究 总被引:4,自引:3,他引:4
要为深入研究新疆盐湖形成演化规律及成盐环境,根据我所历年盐湖科学考察研究结果,对该区盐湖卤水的分布及其化学组成、盐湖卤水的矿化特征和卤水水理性质及水化学类型分类等进行了研究,并通过与我国其它盐湖区盐湖水化学特征的对比分析,确认本区现代盐湖水化学成因类型具有陆相再溶盐成因特征,从而显示了该区盐湖形成演化的独特水文地球化学特点。 相似文献
110.
Abdul A. Rahaman E. Sosamma M. Ambikadevi 《International Journal of Salt Lake Research》1993,2(1):1-15
The hydrobiology of two Indian solar salt works was investigated. A salient feature was variability in physico-chemical and
biological characteristics. The filamentous cyanophyceansLyngbya majuscula andOscillatoria salina and the chlorophyceanXenococcus aceervatus were the major primary producers. Significant fauna were protozoans, rotifers and copepods.Artemia was present in only one set of solar salt pans, where it was dominant. The study illustrates the importance ofArtemia in the biological management of solar salt works.
This paper is dedicated to Thiru. K. Ayyaru Vandayar, Member, Governing body, A.V.V.M. Sri Pshpam College (Autonomous), Poondi,
on his sixtieth birthday 相似文献