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西北干旱地区大气降水δ18O的特征及水汽来源 总被引：7，自引：1，他引：6
In order to reveal the characteristics and climatic controls on the stable isotopic composition of precipitation over Arid Northwestern China, eight stations have been selected from Chinese Network of Isotopes in Precipitation (CHNIP). During the year 2005 and 2006, monthly precipitation samples have been collected and analyzed for the composition of δD and δ18O. The established local meteoric water line δD=7.42 δ18O+1.38, based on the 95 ob-tained monthly composite samples, could be treated as isotopic input function across the region. The deviations of slope and intercept from the Global Meteoric Water Line indicated the specific regional meteorological conditions. The monthly δ18O values were characterized by a positive correlation with surface air temperature (δ18O (‰) =0.33 T (℃)-13.12). The amount effect visualized during summer period (δ18O (‰) = -0.04P (mm)-3.44) though not appeared at a whole yearly-scale. Spatial distributions of δ18O have properly portrayed the atmospheric circulation background in each month over Arid Northwestern China. The quan-titative simulation of δ18O, which involved a Rayleigh fractionation and a kinetic fractionation, demonstrated that the latter one was the dominating function of condensation of raindrops. Furthermore, the raindrop suffered a re-evaporation during falling processes, and the pre-cipitation vapor might have been mixed with a quantity of local recycled water vapor. Multiple linear regression equations and a δ18O-T relation have been gained by using meteorological parameters and δ18O data to evaluate physical controls on the long-term data. The estab-lished δ18O-T relation, which has been based on the present-day precipitation, could be considered as a first step of quantitatively reconstructing the historical environmental climate. 相似文献
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中国南部夏季季风降水水汽来源的稳定同位素证据 总被引：2，自引：0，他引：2
Summer monsoons （South Asian monsoon, South China Sea monsoon and Subtropical monsoon） are prominent features of summertime climate over southern China. Dif- ferent monsoons carry different inflow moisture into China and control the temporal and spatial distributions of precipitation. Analyses of meteorological data, particularly wind, tempera- ture and pressure anomalies are traditional methods of characterizing moisture sources and transport patterns. Here, we try to utilize the evidence from stable isotopes signatures to trace summer monsoons over southern China. Based on seven CHNIP （Chinese Network of Iso- topes in Precipitation） observatory stations located in southern China, monthly composite precipitation samples have been collected and analyzed for the composition of δ^18O during July, 2005. The results indicated that the spatial distributions of δ^18O in precipitation could properly portray the moisture sources together with their transport pathways. Moreover, the amount effect, altitude effect, temperature effect and the correlation between δ^18O vs. relative humidity were discussed. 相似文献
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西北地区大气降水δ18O的特征及水汽来源 总被引：12，自引：0，他引：12
根据2005年各月在中国大气降水同位素观测网(CHNIP)位于西北地区的阜康、策勒、临泽、海北、沙坡头、长武和安塞观测站点收集的降水样品,对其中的同位素的组分进行测定,分析了西北地区大气降水中δ18O的时空分布特征.所建立的局地大气降水线方程δD=7.05δ18O-2.17,反应了西北地区独特的局地气候特点.降水δ18O的温度效应显著,而降水量效应只在夏季(6-8月)间存在.δ18O的空间分布特征可以很好地反映西北地区的大气环流背景.应用瑞利分馏模型及动力分馏模型对阜康-安塞沿线降水δ18O的定量模拟结果,揭示了西北地区降水水汽的分馏主要以动力分馏为主,雨滴在降落过程中历经了一定的二次蒸发过程,其降水水汽中也混入一定量的由局地再蒸发的水汽.此外,利用西北地区在全球大气降水同位素观测网络(GNIP)中的乌鲁木齐、和田、张掖、兰州、银川和西安6个站点的长时间序列的δ18O与降水量、温度等气候因子建立的多元线性回归关系可以对降水δ18O进行定量估算;基于乌鲁木齐站点12年的δ18O资料对该地区的温度拟合,为历史气候的定量恢复提供了依据. 相似文献
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基于CERN的中国大气降水同位素观测网络 总被引：23，自引：0，他引：23
大气降水是水循环的输入项,也是指示气候变化的关键因子.稳定同位素18O、D和放射性同位素T作为水分子的组成要素,是描述水循环演化历史信息的理想天然示踪剂.对降水中氢氧同位素进行系统的观测将有助于明确全球及各局地水循环机制及大气环流模式.首先回顾与评述了全球大气降水同位素网络(GNIP)的发展历程及研究现状,同时,指出中国大气降水同位素观测与研究的不足之处,在此基础上,提出以中国生态系统研究网络(CERN)为基础,建立中国大气降水同位素观测网络(CHNIP),并对该网络的主要内容、特点及初步成果等进行了介绍. 相似文献
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华北平原地下水动态变化 总被引：2，自引：0，他引：2
The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North
China Plain (NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU II of Japan. The automatic
groundwater sensors were installed for the corporation project between China and Japan. Combined with the monitoring results
from 2004 to 2006 with the major factors affecting the dynamic patterns of groundwater, such as topography and landform, depth
of groundwater level, exploitation or discharge extent, rivers and lakes, the dynamic regions of NCP groundwater were gotten.
According to the dynamic features of groundwater in NCP, six dynamic patterns of groundwater level were identified, including
discharge pattern in the piedmont plain, lateral recharge-runoff-discharge pattern in the piedmont plain, recharge-discharge
pattern in the central channel zone, precipitation infiltration-evaporation pattern in the shallow groundwater region of the
central plain, lateral recharge-evaporation pattern in the recharge-affected area along the Yellow River and infiltration-discharge-evaporation
pattern in the littoral plain. Based on this, the groundwater fluctuation features of various dynamic patterns were interpreted
and the influencing factors of different dynamic patterns were compared.
Foundation: National Natural Sciences Foundation of China, No.40671034; No.40830636
Author: Wang Shiqin (1981–), Ph.D., specialized in hydrology and water resources, water cycle of watershed. 相似文献
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