Physio-ecological Adaptation Features Of Quercus Wutaishanica Leaves In Qinling Mountain And Loess Plateau Of Northern Shaanxi Province

Since environmental conditions such as water, temperature, light, and soil, are different among Quercus wutaishanica forests, this study discussed the physio-ecological evolutional adaptation features of Q. wutaishanica in Qinling Mountain and Loess Plateau of northern Shaanxi Province by determining photosynthesis, morphological traits, chemical components, and functional traits of Q. wutaishanica leaves. The main results are as follow:1. The photosynthetic capacity of Q. wutaishanica leaves gradually became weaker from south to north, showing that maximum net photosynthetic rate (Pmax) of Q. wutaishanica leaves were obviously reduced. From the chlorophyll fluorescence parameters, it could be concluded that the lessened actual photochemical quantum yield of PSⅡ(ΦpsⅡ) and apparent electron transport rates (ETR) may be the significant reason for the depressed net photosynthetic rate of Q. wutaishanica leaves in northern site of Loess Plateau.2. From Qinling Mountain to Loess Plateau of northern Shaanxi Province, all leaf area, leaf perimeter, leaf length, leaf width, leaf shape index, stomatal density, and stomatal width of Q. wutaishanica leaves displayed non-linear variational decency, and both leaf thickness and stomatal length had no significant difference among the four sites.3. Leaves of Q. wutaishanica in Qinling Mountain possessed higher contents of N and P, but Q. wataishanica's growth was limited by P element in both Qinling Mountain and Loess Plateau. Q. wutaishanica in Qinling Mountain allocated more resource to defensive matters, while Q. wutaishanica in Loess Plateau accumulated more non-structural carbohydrate, indicating their different strategies of resource allocation.4. In contrast with Loess Plateau, Q. wutaishanica in Qinling Mountain had greater specific leaf area, maximal net photosynthetic rate, and photosynthetic N-use efficiency but less leaf dry matter content, leading faster growth rate and higher productivity. Moreover, leaves of Q. wutaishanica in Loess Plateau possessed lower heat of combustion and construction cost than in Qinling Mountain.In conclusion, due to different environmental conditions, leaves of Q. wutaishanica in Qinling Mountain and in Loess Plateau exhibited different evolutional adaptation features on photosynthesis, morphological traits, chemical components, and functional traits. It demonstrated that Q. wutaishanica adopted different strategies of resource allocation and survival to adapt their different ecological environments.