不同水分条件下西鄂尔多斯6种孑遗植物光合生理特征研究OA

In order to clarify the photosynthetic response processes and mechanisms of different plants to changes in soil moisture.This study studied the variations in net photosynthetic rates of six plants under different moisture conditions and identified their main influ-encing factors.Using the CI-340 portable photosynthesis measurement system,physiological and ecological parameters such as net pho-tosynthetic rate(Pn),transpiration rate(E),water use efficiency(WUE),leaf temperature(Tleaf),stomatal conductance(C),intercellular carbon dioxide concentration(CI),photosynthetically active radiation(PAR),atmospheric temperature(Ta),and air humidity(RH),were measured for Ammopiptanthus mongolicus,Zygophyllum xanthoxylum,Tetraena mongolica,Potaninia mongolica,Prunus mongolica,and Reaumuria songarica before and after water induction.By using Pearson correlation analysis and stepwise regression analysis,the photosynthetic change characteristics of six plants under different water conditions and their relationships with physiological and ecologi-cal factors were systematically studied.The results indicated that there were significant differences in the photosynthetic rates of plants under different moisture conditions.Overall,precipitation positively affected the photosynthetic rates of these plants.However,differ-ent plants had different sensitivities to water changes and distinct response strategies.Among the six plants,five(excluding Tetraena mongolica)demonstrated high photosynthetic strategies following precipitation,while Tetraena mongolica exhibited a low photosynthet-ic strategy.The transpiration rates of plants also varied under different moisture conditions.The transpiration rates of the three plants,Ammopiptanthus mongolicus,Potaninia mongolica and Prunus mongolica,increased after precipitation,indicating a high transpiration response to moisture.In contrast,Zygophyllum xanthoxylum,Tetraena mongolica and Reaumuria songarica,showed low transpiration rates following precipitation.The main factors affecting the six plants before precipitation were WUE,Ls and C,and the main factors af-fecting Pn after precipitation were C,Tleaf and WUE.Additionally,the proportion of influencing factors related to stomatal conductance in-creased after precipitation.