Zhao Na, Meng Ping, He Ya Bing, Lou Yuan Hai, Yu Xin Xiao
Ministry of Education Key Laboratory of Soil and Water Conversation and Desertification Combating, College of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China.
State Forestry Administration Key Laboratory of Tree Breeding and Cultivation, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China.
Ying Yong Sheng Tai Xue Bao. 2017 Jul 18;28(7):2155-2163. doi: 10.13287/j.1001-9332.201707.011.
This study aimed to qualify the potential water sources and their responses to seasonal precipitations for the system of Platycladus orientalis and Vitex negundo var. heterophylla by IsoSource model based on stable hydrogen and oxygen isotopic analysis in Jiufeng Mountain area of Beijing. The results showed that the O of water from 0-20 cm soil layer was enriched, whereas that was depleted as the soil layer deepened. P. orientalis used water mainly from 0-30 cm soil la-yer, being composed of rainwater 2-3 days before at the beginning of dry season. The water absorbed by P. orientalis and V. negundo sourced from 0-10 cm and 10-30 cm soil layer, which was fed on recent rainwater at the end of dry season. In wet season P. orientalis mainly accessed the soil water (from 0-40 cm layer, 59.3%) and recent rainwater (12.5%), while V. negundo drank the water from 0-30 cm soil layer derived from recent heavy rain. P. orientalis actively uptook the deeper soil water with time, until the end of growing season (November), its available water was from 60-80 cm soil layer and sourced from the rainwater happened 2-3 days before. Meanwhile, V. negundo completed its growing cycle and was on the brink of death. This system faced less competition for water use, stating its vertical water availability for climate adaptation in this region, which could reduce water and soil loss and minimize the instantaneous damage under heavy rainstorm attack.
本研究旨在通过基于北京鹫峰山区稳定氢氧同位素分析的IsoSource模型，确定侧柏和荆条系统的潜在水源及其对季节性降水的响应。结果表明，0-20厘米土层的水氧富集，而随着土层加深则贫化。侧柏主要利用0-30厘米土层的水，在旱季开始时由前2-3天的雨水组成。侧柏和荆条吸收的水分别来自0-10厘米和10-30厘米土层，是旱季末期近期的雨水。在雨季，侧柏主要利用土壤水（来自0-40厘米土层，占59.3%）和近期雨水（占12.5%），而荆条饮用的是来自0-30厘米土层的近期大雨形成的水。随着时间推移，侧柏积极吸收更深层的土壤水，到生长季末期（11月），其可用水来自60-80厘米土层，且来源于前2-3天的雨水。与此同时，荆条完成了生长周期，濒临死亡。该系统面临的用水竞争较小，表明其在该地区对气候适应的垂直水资源可用性，这可以减少水土流失，并在暴雨袭击下将即时损害降至最低。
