塔里木荒漠优势树种的光合特性研究

目的]为干旱荒漠区胡杨林的保护及人工栽培提供理论依据。方法]以塔里木盆地2种荒漠优势树种———胡杨和灰叶胡杨为研究对象,比较他们在自然条件下光合生理特性的差异。结果]胡杨叶绿素a、叶绿素(a+b)及叶绿素a/b的含量分别达到(1.39±0.01)、(1.74±0.02)和(4.07±0.07)mg/g,显著高于灰叶胡杨的(1.01±0.03)、(1.35±0.05)和(2.99±0.03)mg/g,二者叶绿素b、类胡萝卜素及类胡萝卜素/叶绿素含量无显著差异;灰叶胡杨的光合能力显著低于胡杨,最大净光合速率、表观量子效率、羧化效率、PSⅡ最大光化学效率和PSⅡ的潜在活性分别为胡杨的68.2%、82.4%、78.8%、98.6%和94.5%。结论]胡杨比灰叶胡杨有更强的光合能力和生态适应性。

Study on Photosynthetic Characteristics of Dominant Tree Species in Tarim Desert

Objective] The study aimed to provide the theoretical basis for protection and artificial cultivation for Populus euphratica Oliv forest in arid desert area.Method] The 2 dominant tree species of P.euphratica and Populus pruinosa Schrenk in tarim basin were taken as tested materials,and the difference of their photosynthetic physiological characteristics was compared under the natural conditions.Result] The contents of chlorophyll a,chlorophyll(a+b) and chlorophyll a/b in P.euphratica reached(1.39±0.01),(1.74±0.02) and(4.07±0.07) mg/g resp.,being significantly higher than that in P.pruinosa(1.01±0.03),(1.35±0.05) and(2.99±0.03) mg/g.The content of chlorophyll b,carotenoid and the ratio of carotenoid to chlorophyll in P.euphratica and P.pruinosa had no significant difference.The photosynthetic capacity of P.pruinosa was lower than that of P.euphratica significantly,and the maximum net photosynthetic rate,apparent quantum efficiency,carboxylation efficiency,maximal photochemical efficiency of PSⅡ and potential activity of PSⅡin P.pruinosa were 68.2%,82.4%,78.8%,98.6% and 94.5% resp.of those in P.euphratica.Conclusion] Compared with P.pruinosa,the P.euphratica had more strong photosynthetic capacity and ecological adaptability.