海南土壤中Zn、Pb、Cu、Cd四种重金属含量及其生物有效性的研究   总被引：22，自引：0，他引：22  

朱维晃  杨元根  毕华  刘强 《矿物学报》2004,24(3):239-244

对海南0个土壤样品中的nl、Pb、Cu、0四种重金属的总量和生物有效态含量以及45个植物样(根、茎、叶)中的重金属含量分别进行了测定，采样点基本上覆盖了海南全省，测定结果表明，土壤中nl总量低于全国平均值，而Pb、Cu、Cd高于全国平均值，土壤中重金属生物有效态含量一般低于其总量的10％，其中Pb最高为7．71％，而Cu仅为1．13％，具有较大的变异性；植物中重金属含量与土壤中重金属总量呈现负相关性，但与土壤中有效态重金属含量一般呈现正相关性，叶中的重金属含量与土壤中有效态重金属含量之间的相关性更为显着，叶中的重金属含量与土壤中有效态重金属含量之间的相关系数分别为：Zn(0．726)，Cu(0．626)，Pb(0．n4)，Cd(0．512)。这说明土壤中重金属总量并不能全面的评价土壤的环境效应和重金属的生物有效性，应该把重金属总量和生物有效态含量结合起来加以研究，并应将土壤中重金属的含量与植物中该元素含量之间作相关分析，根据其相关系数的大小来判断其生物有效性的程度。  相似文献   

青岛市沿海地区的商陆属植物     

李宝华  周莉  赖冰心 《海岸工程》2003,22(3):93-95

分述青岛市沿海地区商陆科、商陆属植物的种类、形态特征、分布状况、用途及栽培方法。为保护和发展该地区商陆属植物资源，满足沿海各地医药、园林等部门需求提供科学依据。  相似文献   

我国鱼类生殖生理学研究概况   总被引：6，自引：1，他引：6  

施瑔芳 《海洋与湖沼》1992,23(3):325-333

我国从50年代开始,根据渔业生产的需要,成功地进行了几种家鱼的人工繁殖试验。同时,也开展了鱼类生殖生理学的基础研究,使工作不断深入和提高。本文综述了我国40年来一系列有关鱼类生殖生理学的研究概况。  相似文献   

电厂冷却水余氯对海洋环境影响的探讨   总被引：3，自引：0，他引：3  

温伟英  黄小平  吴仕权  何悦强 《热带海洋学报》1993,(3)

根据室内实验和对广东某电厂的现场测试,探讨该电厂冷却水经氯化处理后,海水中余氯的衰减特征和余氯对水环境的影响。研究表明,余氯衰减很快,其对外环境的影响很小。  相似文献   

澜沧江-湄公河水电站单位发电耗水量分析计算          下载免费PDF全文

陆颖  何大明  何开为  袁旭 《水科学进展》2018,29(3):415-423

为对比澜沧江-湄公河流域各国水电开发对水资源消耗的差异,选择流域范围内37座已建主要电站,基于遥感再分析资料,运用改进的水电站水足迹方法核算并分析2015年流域各国水电站水足迹及其年内变化。结果表明:流域中国段水电站水足迹最小,具有最高的单位耗水量发电效率;老挝及泰国水电站水足迹普遍偏大,发电效率低且耗水量巨大。因此,从发电水资源消耗角度看,流域内地处上游的中国江段较适宜水电开发,下游国家发展水力发电需考虑水资源消耗影响。  相似文献   

Latest Neogene Paleoclimate Variation in Yunnan,Southwest China,Revealed by Fossil Leaf Physiognomy     

DAI Jing  CHEN Weizhao  HUANG Liang  ZHANG Yi’nan 《《地质学报》英文版》2023,97(4):1268-1281

Yunnan Province, located in the southeastern margin of the Tibetan Plateau, can provide important information on how climate change was influenced by global cooling. However, its variation patterns in temperature and precipitation during the latest Neogene are not well-understood. Based on the 357 specimens assigned to 31 morphotypes of plant fossils from the upper Pliocene Ciying Formation in Yiliang County, Yunnan Province, Southwest China, paleoclimate was estimated by Leaf Margin Analysis an...  相似文献   

我国内陆核电的用水安全          下载免费PDF全文

张爱玲  陈晓秋  刘森林  贾祥 《水文》2015,35(3):69-73

在介绍我国拟建内陆核电机组的安全设计和厂用水系统的基础上,分析了内陆核电的用水需求和保证率要求。结合我国水资源条件及水资源论证现状,对如何保障内陆核电取水水源的可靠性与可行性进行了探讨,并提出了内陆核电用水安全保障措施的建议。  相似文献   

Paleoecology of Oligocarpia gothanii Halle from the Middle Permian of Southeastern Shanxi, North China     

HE Xuezhi  WAN Mingli  YAN Mengxiao  CHENG Chen  WANG Shijun  WANG Jun 《《地质学报》英文版》2015,89(4):1063-1075

Fossil ferns are abundant and diverse in the Permian Cathaysian Flora of Shanxi, North China. Although plants assemblages of the Carboniferous and Permian have been extensively investigated, their palaeoecology and especially the paleoecology of ferns has not been studied in detail. Recent reinvestigation of Oligocarpia gothanii has revealed its growth habit and cloning reproduction strategy, but most previous studies lack integrated sedimentological and taphonomic data. In this study, new materials of O. gothanii have been collected from a floodplain setting in the middle Permian Lower Shihhotse Formation of southeastern Shanxi. These plant fossils were found in a lenticular claystone associated with rooting structures. They are characterized by aphlebia at the base of the penultimate rachis. Sedimentological, taphonomic and morphological analyses were conducted to understand the growth habit and ecology of the fern. The result indicates that the Oligocarpia gothanii had a prostrate, ground cover growth habit, and was dominant in pioneer floras that colonized disturbed floodplains.  相似文献   

Seasonal change mediates the shift between resource and pollen limitation in Hedysarum scoparium (Fabaceae)     

ChengChen Pan  Qi Feng  HaLin Zhao  XueYong Zhao  LinDe Liu  JiLiang Liu  Li Zhang  Jin Li 《寒旱区科学》2015,7(1):0094-0098

Theory suggests that with sufficient environmental variation, pollen limitation might be observed at some places or times, and resource limitation at others, but there are no empirical data about the effect of seasonal change on the variation of pollen limitation and resource limitation within a flowering season. In this study, we examined pollen and resource limitation by comparing fruit set and seed production in natural- and hand-pollinated Hedysarum scoparium flowers in the middle reaches of the Hexi Corridor region, China, in 2010. We also described a role for the first substantial autumn rainfall in mediating a shift between pollen and resource limitation in H. scoparium, but did not analyze this experimentally. Our results indicated that H. scoparium was resource limited at peak flowering during the summer, and was pollen limited at peak flowering during the autumn. The seasonal change (summer to autumn) mediated the shift between pollen and resource limitations in H. scoparium. The shift timing depended on the date of the first autumn rainfall in 2010. Changes in the first substantial rainfall in autumn may affect fruiting of H. scoparium, thus affecting population persistence of this species and development/structure of the local ecosystem if such conditions persist.  相似文献   

条子泥围垦区水盐特征与植被分布的关系          下载免费PDF全文

詹泸成  马芬艳  陈建生  辛沛 《水科学进展》2021,32(1):127-138

为了探究江苏东台条子泥围垦区的水盐分布规律,揭示圆环状植被分布与土壤水盐条件的关系,于2019年9月对围垦区内用作湿地恢复的区域进行测量和采样。在植被环附近测量了二维、三维大地电阻率,采集降水、地表水、土壤、地下水等样品,测试样品的水盐指标和D、18O同位素组成。结果表明:植被圆环下方3 m深度内均存在对应的高电阻率/低盐度区域,且随着植被类型由中心向外环变化,对应的土壤水盐度也逐渐增大;土壤水盐度是不同植被呈现圆环状分布的重要影响因素,其变化受降水入渗和土壤蒸发引起的盐分集结共同作用;土壤盐度直接影响了不同植被种群的分布格局,而植被对入渗和蒸发过程的影响也反作用于土壤盐度分布。  相似文献