青藏高原湖泊Mg^(2＋)、Ca^(2＋)和Mg/Ca盐度指示意义的初步分析  

Preliminary analysis on Mg^(2+),Ca^(2+) and Mg/Ca as salinity indicators of lakes in the Qinghai-Tibetan Plateau

作　　者：王海雷[1,2,3] 王云生[1,2,3] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]国土资源部盐湖资源与环境重点实验室,北京100037 [3]中国地质科学院盐湖与热水研究发展中心。北京100037

出　　处：《湖泊科学》2010年第6期894-900,共7页Journal of Lake Sciences

基　　金：中央级公益性科研院所基本科研业务费专项资金项目(K2007-3-2,K0918);中国地质科学院重点实验室专项基金项目(K0915);国家自然科学基金重点项目(40531002);国家地质大调查项目(1212010818057)资助

摘　　要：总结了青藏高原地区400多个湖泊湖水的Mg2+、Ca2+和Mg/Ca等水化指标与湖水盐度的相关关系,以及这种关系随着湖水变化(不同采样时间和采样点以及自然蒸发)而产生的变化规律.结果表明:青藏高原湖泊湖水的Mg2+浓度与盐度具有较为稳定的正相关关系,而Ca2+和Mg/Ca与盐度的相关性较弱.在对于某一特定水化学类型的湖泊,一般碳酸盐型湖泊的Mg2+、Ca2+以及Mg/Ca等指标与盐度均没有明显的相关性;硫酸盐型湖泊中Mg2+浓度和盐度呈现较高的正相关关系,而Ca2+以及Mg/Ca与盐度的相关性仍很弱;而在氯化物型湖泊中,Mg2+浓度与盐度呈更高的正相关性,Ca2+浓度也与盐度呈一定的正相关性,Mg/Ca这一指标与盐度的相关性依然很弱.而对某一特定湖泊,在不同演化阶段或不同的采样地点,Mg2+浓度与盐度仍然保持明显的正相关关系,而Ca2+以及Mg/Ca与盐度的相关性仍然不稳定或很弱.在青藏高原作古环境重建应用的时候,湖水Mg2+浓度是古盐度一个较好的转换指标,而Ca2+以及Mg/Ca的古盐度指示意义相对较弱.This paper summarizes the relationships between hydrochemical proxies of Mg2＋,Ca2＋,Mg/Ca and the salinity from more than four hundred lakes in the Qinghai-Tibetan Plateau.We discuss its variation characteristics by different samples from varied place and time,as well as natural evaporation.Mg2＋ shows a stable positive relationship with salinity in lakes in the Qinghai-Tibetan Plateau,while Ca2＋,Mg/Ca show poor and unstable relationships with salinity.For carbonate water types in the lakes,however,no significant relationship is observed between Mg2＋,Ca2＋ and Mg/Ca and salinity in carbonate typed lakes.Mg2＋ shows positive relationship with salinity in sulphate typed lakes,and Ca2＋,Mg/Ca remains poor relationship with salinity.While in chloride typed lakes,Mg2＋ shows distinct positive relationship with salinity,and Ca2＋ also shows positive relationship to some extent with salinity.Mg/Ca still shows no clear relationship with salinity.In individual lakes,Ca2＋ and Mg/Ca still show unstable and/or poor relationship with salinity,while Mg2＋ keeps remarkable positive relationship with salinity.It is concluded that Mg2＋ is a useful indicator for paleosalinity reconstruction in the Qinghai-Tibetan Plateau.

关 键 词：青藏高原 湖泊 Mg2+ CA2+ MG/CA 盐度 相关性 

分 类 号：P342[天文地球—水文科学]