干旱区生态环境知识资源中心(Arid): 共生条件下三种荒漠灌木的根系分布特征及其对降水的响应

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	共生条件下三种荒漠灌木的根系分布特征及其对降水的响应
其他题名	Roots distribution of three desert shrubs and their response to precipitation under co-occurring conditions
	徐贵青; 李彦
ISSN	1000-0933
出版年	2009
卷号	29 期号:1 页码:130-137
中文摘要	以全根系挖掘法,对共生于原始盐生荒漠生境中的多枝柽柳[Tamarix ramosissima(Ledeb.)]、梭梭[Haloxylon ammoden-dron(C.A.Mey.)Bunge]、琵琶柴[Reaumuria soongorica(Pall.)Maxim.]的根系分布特征进行了研究;对降水引发的湿润-干旱周期中植物同化枝水势、蒸腾速率的变化过程进行了跟踪观测,并据此计算3种植物的水分胁迫效应指数和土壤-植物系统导水度,以最终确定3种植物用水策略和其对降水的响应特征。研究结果表明,多枝柽柳的吸收根系分布范围从地下50cm到310cm,单株平均总吸收根表面积为30249.2cm2;梭梭的根系分布范围0250cm,单株平均总吸收根表面积12847.3 cm2;琵琶柴的根系分布范围080cm,单株平均总吸收根表面积361.8 cm2。多枝柽柳为深根植物,主要利用地下水和深层土壤水,在降水引发的湿润-干旱周期中,其植物水分生理参数对降水无响应。琵琶柴为浅根植物,对降水响应极为显著。梭梭的根系分布特征介于多枝柽柳和琵琶柴之间,对地下水和降水都有利用,对降水响应显著。3种荒漠灌木对降水的响应差异显然与其根系分布、水分利用策略密切相关,在未来降水发生变化的情景下,根系分布特征的差异将决定着植物在水分资源竞争中的地位。具有较强根系形态可塑性的物种,如梭梭,将具有明显的竞争优势。
英文摘要	Root distribution of three desert shrubs,Tamarix ramosissima Ledeb.,Haloxylon ammodendron(C.A.Mey.) Bunge and Reaumuria soongorica(Pall.) Maxim.were investigated under co-occurring conditions using whole root system excavation method.Assimilatiion shoot water potential and transpiration rate were monitored during the wet-dry circle induced by rain events.Leaf-specific apparent hydraulic conductance and the index of water stress impact for the three species were calculated from shoot water potential and transpiration rate.The results showed that the root system of T.ramosissima mainly distributed at 50 to 310cm below soil surface,with average total absorbing root surface area at 30249.2cm2 per plant;The root system of H. ammodendraom distributed at 0 to 250cm below soil surface with average total absorbing root surface area at 12847.3 cm2 per plant;The root system of R.soongorica distributed at 080cm,with average total absorbing root surface area at 361.8 cm2.The root distribution shows that,T.ramosissima uses the ground water as the main water resource;H.ammodendraom uses both ground water and rain water;R.soongorica uses rain water only.During the wet-dry cycle induced by raining events,hydraulic parameters of T. ramosissima showed no responses to precipitation.R.soongorica responded most significantly,the responses of H.ammodendraom were in between.In conclusion,the plant responses towards rain events closely related to their root distribution and plant water-use strategy.Under the scenario of the predicted precipitation changes in the future,the discrepancy of root distribution will partially determine the position of the studied species in water resource competition.Species that have the superior root morphological plasticity,such as H. ammodendron,will have significant advantage in competing for water resources.
中文关键词	土壤含水量 ; 根系分布特征 ; 同化枝水势 ; 蒸腾速率 ; 单位同化枝导水度
英文关键词	soil water content root distribution assimilation shoot water potential transpiration rate leaf-specific apparent hydraulic conductance
语种	中文
国家	中国
收录类别	CSCD
WOS类目	ECOLOGY
WOS研究方向	Environmental Sciences & Ecology
CSCD记录号	CSCD:3492686
来源机构	中国科学院新疆生态与地理研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/224026
作者单位	中国科学院新疆生态与地理研究所阜康荒漠生态站, 乌鲁木齐, 新疆 830011, 中国
推荐引用方式 GB/T 7714	徐贵青,李彦. 共生条件下三种荒漠灌木的根系分布特征及其对降水的响应[J]. 中国科学院新疆生态与地理研究所,2009,29(1):130-137.
APA	徐贵青,&李彦.(2009).共生条件下三种荒漠灌木的根系分布特征及其对降水的响应.,29(1),130-137.
MLA	徐贵青,et al."共生条件下三种荒漠灌木的根系分布特征及其对降水的响应".29.1(2009):130-137.