Water sources and water-use efficiency of desert plants in different habitats in Dunhuang, NW China
Water sources and water-use efficiency of desert plants in different habitats in Dunhuang, NW China
复制标题
敦煌不同生境荒漠植物的水资源及水分利用效率
DOI：
10.1007/s11284-017-1433-8
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发表时间：
2017-03-01
影响因子：
2
通讯作者：
Sun, Wei
中科院分区：
文献类型：
--
作者：
Cui, Yong-Qin;Ma, Jian-Ying;Sun, Wei
为了解荒漠植物水分利用模式与生境相关的差异，在敦煌3种典型生境（盐碱地、桑迪和戈壁）中，利用水稳定氧同位素组成确定水源，利用叶片碳同位素组成（δ C-13）估算长期水分利用效率。主要调查结果如下：（1）在三种生境中，植物种类主要利用深层土壤水分（2）在盐碱地和戈壁生境中，疏叶骆驼刺具有最负的叶片δ C-13;在桑迪，2011年沙枣叶片C-13含量高于其它3种植物，2012年4种植物叶片C-13含量差异不显著;（3）常见种（多枝柽柳（Tamarix ramosissima）和A. sparsifolia）可能会改变水源以科普生境差异，与土壤水分有效性的变化相关，与盐碱地和桑迪相比，在土壤含水量（SWC）较低的戈壁生境中使用较深的水源;（4）我们检测到A. sparsifolia，这可能是由于SWC和土壤电导率的差异。然而，没有观察到叶三角洲C-13的栖息地差异，在T。ramosissima，这可能与T. ramosissima或获得稳定的深层土壤水分的能力。总体而言，研究结果表明，极端干旱气候、根系分布和土壤性质共同决定了敦煌地区植物的吸水量。
To understand habitat associated differences in desert plant water-use patterns, water stable oxygen isotope composition was used to determine water source and leaf carbon isotope composition (delta C-13) was used to estimate long-term water-use efficiency in three typical habitats (saline land, sandy land and Gobi) in Dunhuang. The primary findings are: (1) in the three habitats, plant species used mainly deep soil water (> 120 cm), except for Kalidium foliatum in the saline land, which relied primarily on 0-40 cm soil water; (2) in the saline land and Gobi habitat, Alhagi sparsifolia had the most negative foliar delta C-13; in the sandy land, Elaeagnus angustifolia leaf was enriched in C-13 than the other three species in 2011, but no species differences in foliar delta C-13 was observed among the four species in 2012; (3) common species (Tamarix ramosissima and A. sparsifolia) may alter their water sources to cope with habitat differences associated changes in soil water availability with deeper water sources were used in the Gobi habitat with lower soil water content (SWC) compared to in the saline land and sandy land; (4) we detected significant habitat differences in foliar delta C-13 in A. sparsifolia which may have resulted from differences in SWC and soil electrical conductivity. However, no habitat differences in foliar delta C-13 were observed in T. ramosissima, which may attribute to the strong genetic control in T. ramosissima or the ability to access stable deep soil water. Overall, the results suggest that extremely arid climate, root distribution and soil properties worked together to determine plant water uptake in Dunhuang area.