Variation of the stable isotopes of water in the soil-plant-atmosphere continuum of a Cinnamomum camphora woodland in the East Asian monsoon region
Variation of the stable isotopes of water in the soil-plant-atmosphere continuum of a Cinnamomum camphora woodland in the East Asian monsoon region
复制标题
东亚季风区香樟林土壤-植物-大气连续体中水稳定同位素的变化
DOI：
10.1016/j.jhydrol.2020.125199
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发表时间：
2020-10
影响因子：
6.4
通讯作者：
Guan Huade
中科院分区：
文献类型：
--
作者：
Dai Junjie;Zhang Xinping;Luo Zidong;Wang Rui;Liu Zhongli;He Xinguang;Rao Zhiguo;Guan Huade
氢氧稳定同位素（2H和18O）示踪法已成为研究大气、江河湖泊、土壤、植物和含水层之间水分传输的重要手段。我们对位于东亚季风区的中国中南部长沙樟树林地的土壤-植物-大气连续体中的水稳定同位素变化和樟树用水季节变化进行了研究。 2017年3月至2019年8月，对降水、土壤水（0~130cm深度）、地下水、樟树枝条木质部水进行稳定同位素监测，同时测量相关环境变量（土壤含水量、气象变量），对监测数据进行整理分析，确定不同水池稳定同位素的变化情况及相互交换情况。结果表明，日降水量（P）大于3.7毫米（视为有效降水）有助于土壤水分补给。土壤水和枝条木质部水的同位素组成均低于LMWLP>3.7（当地大气水线消除了P≤3.7mm的降雨事件）。浅层土壤水（0-60 cm）和树枝木质部水的同位素组成与两个月内累计前期降水量呈正相关。这些降水同位素信号传播模式描绘了土壤和植物连续体中水分传输的清晰途径。研究区土壤水线斜率高于LMWLP>3.7，因为蒸发需求较大的暖季降水比蒸发需求较低的冷季降水重同位素消耗更多（即负δ值更多）。因此，基于同位素水线法来确定同位素分馏的强度是不可行的。根据MixSIR模型，观测期间樟树吸水主要来源于浅层土壤水。然而，在 7 月至 9 月土壤干燥时，深层土壤水（60-130 厘米）对 C 产生了贡献。樟脑水吸收约50%。这些发现提高了我们对东亚季风区土壤-植物-大气连续体水循环的理解。
The hydrogen and oxygen stable isotopic (2H and18O) tracer method has become an important means of studying water transfer between the atmosphere, rivers and lakes, soils, plants, and aquifers. We conducted a study on the variations of the stable isotopes of water, and the seasonal variations in water use ofCinnamomum camphora, in the soil-plant-atmosphere continuum in aC.camphorawoodland in Changsha, central-southern China, which lies within the monsoon region of East Asia. Stable isotopes were monitored in precipitation, soil water (0–130-cm depth), groundwater, twig xylem water ofC.camphora, and at the same time relevant environmental variables (soil water content, and meteorological variables) were measured, from March 2017 to August 2019. The monitoring data were collated and analyzed to determine the variations of stable isotopes in different water pools and mutual exchanges. The results indicate that daily precipitation (P) greater than 3.7 mm (regarded as effective precipitation) contributed to soil water replenishment. Isotopic composition of soil water and twig xylem water fell below the LMWLP>3.7(the local meteoric water line eliminated rainfall events with P ≤ 3.7 mm). Isotopic composition of shallow soil water (0–60 cm) and twig xylem water was positively correlated with that of cumulative antecedent precipitation within two months. These patterns of precipitation isotopic signal propagation delineate a clear pathway of water transfer in this soil and plant continuum. The slope of the soil water line in the study area was higher than that of the LMWLP>3.7because of the situation that precipitation in warm season with a larger evaporative demand is more depleted with heavy isotopes (i.e., more negative delta values) than that in cold season when the evaporative demand is low. Therefore, it was not feasible to determine the strength of isotopic fractionation based on the isotopic water line method. According to the MixSIR model,C.camphorawater uptake mainly sourced from shallow soil water during the observation period. However, in July-September when soil was dry, deep soil water (60–130 cm) contributed toC. camphorawater uptake for ~50%. These findings improve our understanding of the water cycle of the soil-plant-atmosphere continuum in the East Asian monsoon region.
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影响因子：
6.3
作者：
M. Sprenger;D. Tetzlaff;C. Soulsby
通讯作者：
M. Sprenger;D. Tetzlaff;C. Soulsby
影响因子：
2.8
作者：
C. Gierke;B. Newton;F. Phillips
通讯作者：
C. Gierke;B. Newton;F. Phillips
华北平原浅层地下水区两点土壤水势与稳定同位素相结合的土壤水运动研究
影响因子：
3.2
作者：
宋献方;王仕琴*;肖国强;王志民;刘鑫;王鹏
通讯作者：
王鹏
DOI：
10.13287/j.1001-9332.201906.013
发表时间：
2019-06
期刊：
Ying yong sheng tai xue bao = The journal of applied ecology
影响因子：
--
作者：
Xiaomin Ma;Jingjing Jin;B. Si;W. Xiang;Hong Wang
通讯作者：
Xiaomin Ma;Jingjing Jin;B. Si;W. Xiang;Hong Wang
DOI：
--
发表时间：
2012-03
期刊：
Ying yong sheng tai xue bao = The journal of applied ecology
影响因子：
--
作者：
Liping Cheng;Wenzhao Liu
通讯作者：
Liping Cheng;Wenzhao Liu