莱州湾地区10万年以来沉积环境变化   总被引：11，自引：0，他引：11  

彭子成  韩有松 《地质论评》1992,38(4):360-367

本文用热释光测年和地球化学标志法研究了莱州湾地区沉积环境的变化。石英的375℃热释光峰作为测年基础。岩芯样品的测定结果、反映了自全新世(1.2万年)至晚更新世(11万年)地层的年代特点。实验中来用了Sr/Ba、Rb、Mn/Fe和CaO作为地球化学标志,所得数据经Sheppard方程和Fisher判别处理。在得到的沉积环境变化曲线和大洋δ~(18)O曲线对比中可以看出,本区在十万年以来出现过三次海陆相地层变化序列,其中在距今11—7万年和深度为43.5—60m处,在距今4.6—2.1万年和深度为23—35m处,以及在距今1.1—0.6万年和深度为8—11m处出现过三次海相地层,分别与沧州、献县和黄骅海侵事件相应,并同时受到全球气候变化的控制。  相似文献   

福建上杭紫金山铜金矿床地质简介   总被引：2，自引：0，他引：2  

姚金炎  彭振安 《矿产与地质》1992,6(2):89-94

以宏观角度介绍紫金山铜金矿床地质背景,论述了火山机构、次火山岩、隐爆角砾岩、围岩及围岩蚀变、矿化带及矿化特征,着重总结该矿床找矿标志,以期在地质找矿中得以借鉴。  相似文献   

BIOCHEMICAL CHANGES DURING DEVELOPMENT OF EGGS AND YOLK-SAC LARVAE OF HERRING AND PLAICE   总被引：2，自引：1，他引：2  

殷名称  J.C.A.Craik 《中国海洋湖沼学报》1992,10(4):347-358

Changes in quantities of water, sodium, potassium, lipid and protein were compared in developing eggs and yolk-sac larvae of herring dupes harengus L., a species with demersal eggs, and plaice Pleuroncctcs platessa L., a species with pelagic eggs. The principal difference between the two species was the occurrence in herring, but not in plaice of considerable increases in water content and in one or both of the above ions at three distinct stages: at fertilization,during the middle stage of egg development, and in the days immediately after hatching. Newly hatched larvae of the two species differed greatly in water content because of the difference in mass and water content of the yolk, not in the water content of the rest of the body. In herring, there were increases in sodium and potassium which coincided broadly with the increase in water content. These differences are related to the gradual acquisition of buoyancy by herring during this period, comparable with the buoyancy conferred on plaice eggs a  相似文献   

Comparing performance indicators to characterize the water supply to the demands of the Guadiana River basin (Spain)     

Carla Palop-Donat  Javier Paredes-Arquiola  Abel Solera  Joaquín Andreu 《水文科学杂志》2020,65(7):1060-1074

ABSTRACT

Water indicators and indices are useful tools to assess river basin performance, that is, to measure whether the basin operates satisfactorily under a wide range of possible future demands and hydrological conditions. Spanish regulations assess the performance of water demands by using reliability indicators (RIs), established by law in 2008. This article raises the possibility of updating RIs by comparing them with sustainability indicators (SIs). SIs are widely used for the assessment of river basin performance and several policy scenarios. We applied a water allocation model to the Guadiana River basin in Spain to compare indicators under three scenarios. The study was framed within the science of socio-hydrology, combining the physical environment of a water system with its influence on social aspects. SIs gave better results than RIs when comparing future scenarios. We also propose the introduction of a vulnerability indicator into Spanish regulations.  相似文献   

可持续发展指标体系及综合评价研究评述   总被引：5，自引：0，他引：5  

邱茂慧  陈忠暖  蔡霞 《热带地理》2002,22(3):222-226

可持续发展指标体系研究和可持续发展综合评价研究是可持续发展进程的一部分,是连接可持续发展战略理论与战略实施的桥梁,文中对近年来国内外出现的有关研究做了简要概括,分析了各研究成果的优缺点,总结了研究的发燕尾服特点并展望了研究的前景。  相似文献   

A Basic Water Quality Model for the River Neckar: Part 2 – model‐based analysis of the oxygen budget and scenarios     

Ingo Haag 《洁净——土壤、空气、水》2006,34(6):549-559

In this paper the Basic Water Quality Model (BWQM) for the central part of River Neckar is used to analyse the oxygen budget and to assess the potentials of various measures to prevent or mitigate critical dissolved oxygen (DO) declines. It is shown that the oxygen budget is mainly governed by phytoplankton dynamics. The excessive growth of algae and the sudden break down of the resulting algal blooms may cause episodic DO depressions. Therefore, to stabilise the oxygen budget in a sustainable way, eutrophication has to be controlled within the central part of River Neckar and the upstream regions. The only feasible way to reach this goal appears to be a further drastic reduction of phosphorus emissions. In addition, it is indispensable to hold the very high standards of biochemical oxygen demand and ammonium retention at the wastewater treatment plants. A worse performance of the treatment plants would dramatically aggravate critical DO declines which may be caused by algae dynamics. As long as the oxygen budget is not completely stabilised, weir and turbine aeration can be used to mitigate DO depressions. It could be shown that the potentials of these measures suffice to keep DO at a tolerable level. However, due to the long travel times in River Neckar, it is important to start aeration up to several days before the DO minimum is reached.  相似文献   

甘肃代家庄铅锌矿床地球化学异常特征   总被引：2，自引：0，他引：2       下载免费PDF全文

张忠平 《甘肃地质》2006,15(2):42-47

代家庄铅锌矿床是通过区域化探异常查证工作,在西秦岭地区发现的SEDEX型铅锌矿床。本文根据代家庄矿区水系沉积物、土壤和岩石剖面测量结果,对Pb、Zn等成矿元素的分布特征和组合关系进行了分析,初步总结了代家庄铅锌矿床的地质和地球化学异常特征,归纳出该矿床的地球化学找矿标志,提出了找矿方向。  相似文献   

金矿的地质地球化学找矿标志     

薛水根 《江苏地质》2007,31(1):7-9

地层和岩浆岩含金高丰度是金矿赋集的物质来源,断裂构造是容矿、储矿的空间。一般说来,金成矿物质越丰富,就越有利于形成大矿、富矿。以江西金矿找矿为例,阐述正确圈定金异常,合理布置探矿工程,获得找金成果新突破的实际意义。  相似文献   

基于PROSPECT＋SAIL模型的遥感叶面积指数反演   总被引：4，自引：1，他引：4  

蔡博峰  绍霞 《国土资源遥感》2007,18(2):39-43

以PROSPECT+SAIL模型为基础，从物理机理角度反演植被叶面积指数(LAI)。首先，通过FLAASH模型进行大气校正，使得图像像元值表达植被冠层反射率； 然后，根据LOPEX 93数据库和JHU光谱数据库选择植物生化参数和光谱数据，以PROSPECT模型模拟出的植物叶片反射率和透射率作为SAIL模型的输入参数，得到植被冠层反射率，将结果与遥感影像的植被冠层反射率对应，回归出植被LAI； 最后，以地面实测数据对遥感反演数据进行验证，并分析了误差的可能来源。  相似文献   

Nonrenewable resources in economic, social, and environmental sustainability     

Deborah J. Shields 《Natural Resources Research》1998,7(4):251-261

This paper reviews the linkages among energy and mineral resources and economic, social, and environmental sustainability. Nonrenewable resources are shown to be integral components of sustainability, regardless of which paradigmatic definition of the concept is invoked. Potential measures of the degree to which nonrenewable resources contribute to or detract from sustainability are presented. We conclude that a set of such measures should be incorporated in the comprehensive framework of sustainability currently being developed by the Federal government. National scale indicators could be presented within the structure of the seven criteria from the Santiago Declaration, whereas a life cycle or materials flow approach could be used when sustainability of specific resources is at issue.  相似文献