模糊隶属法在塔里木河荒漠植物抗旱性评价中的应用

以塔里木河荒漠河岸乔木、灌木、草本植被的代表植物胡杨(Populus euphratica)、柽柳(Tamarix ramosissima)和罗布麻(Apocynum venetumas)为研究对象,对塔里木河下游不同区段、不同地下水位状况下胡杨、柽柳和罗布麻体内叶绿素、可溶性糖、脯氨酸(Pro)、丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化物酶(POD)、生长素(IAA)、赤霉素(GA3)和脱落酸(ABA)等主要生理指标和地下水位进行了测定。运用国际通用软件SAS6.12对这十项生理指标和地下水位之间的关系进行了相关性分析,结果表明:亚哈甫马汗断面的柽柳对地下水位的生理响应最为敏感。其次是胡杨和罗布麻;阿拉干断面的差异不大;在所测的十项生理指标中,丙二醛(MDA)、超氧化物歧化酶(SOD)、脱落酸(ABA)对地下水位变化的敏感度最高,其次为过氧化物酶(POD)、生长素(IAA)和分裂素(CK);地下水位是影响塔里木河流域植被生理特性的主要环境因子。在相关分析的基础上运用平均隶属函数法对这三种植物进行抗旱性排序,结果表明:在干旱胁迫下,植物各种生理代谢过程协同作用,共同抵御干旱胁迫,以减少其受伤害程度;就抗旱能力而言,胡杨>柽柳>罗布麻。

Evaluation on the Drought-Resistant Capability of the Riparian Desert Vegetation Along the Tarim River, Xinjiang

Three dominant riparian arbor, shrub and herb species, i.e., Populus euphratica, Tamarix ramosissima and Apocynum venetumas growing along the Tarim River, are studied in this paper. The main physiological indexes, such as chlorophyll, soluble sugar, proline (Pro), malondialdehyde (MDA), superoxide dismutase (SOD), peroxidase (POD), abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellins (GA) and cytokinin (CK) of these three plant species growing along the different sections of lower reaches of the Tarim River and under the different groundwater depths, were measured. A correlation analysis between the 10 physiological indexes and the groundwater level is carried out using the commonly used software SAS 6.12. The results show that the physiological response of Tamarix ramosissima to groundwater level along the Yahopmarhan section is the most sensitive, then that of Populus euphratica and Apocynum venetumas; the difference of physiological response of these three plant species growing along the Aragan section to groundwater level is not so significant. Among the physiological indexes measured, MDA, SOD and ABA are the most sensitive to the change of groundwater level, then that of POD, IAA and CK. Groundwater level is a dominant environmental factor affecting the physiological characteristics of plants in Tarim River Watershed. Based on the correlation analysis, the average subordinative function method is used to carry out a comprehensive evaluation and a comparison research on Populus euphratica, Tamarix ramosissima and Apocynum venetumas, and the results show that the various physiological metabolism processes cooperate with each other for jointly resisting moisture stress and reducing the damaged degree. The drought-resistant capability of the three plant species is in an ordination of Populus euphratica > Tamarix ramosissima > Apocynum venetumas.