Clonal Growth Of Staple Food Bamboo For Giant Panda Under Canopy Conditions In A Subalpine Coniferous Forest

The staple food bamboo in the spruce-fir forest play a fundamental role for Giant panda to survive and reproduce.Meanwhile,they have crucial affect on the structure and dynamics of the habitat forests of Giant panda in the subalpine areas of southwest China,by influencing the establishment and growth of tree species' seedling populations.It is important to study the plasticity of clonal growth of staple food bamboo to different canopy conditions.Therefore,Fargesia denudata,one of the Giant Panda's main food sources,was chosen as the experimental materials to show how the staple food bamboo adapt to different canopy conditions[forest understory(Fu),small gap(Sg),middle gap(Mg),and large gap(Lg)]in an Abies Faxoniana forest in Wanglang National Nature Reserve in the northwest Sichuan, China,by studying:(1).the clonal growth of F.denudata under different canopy conditions;(2).The suitable environmental conditions for F.denudate to survive and grow well;(3).The effect of parent ramets on new shoots.The results showed that the ramet density was not significantly different, although the new shoot density was significantly different in these four canopy conditions;The value of ramet biomass,height,basal diameter and module biomasses were highest in the Sg compared to Fu,Mg and Lg canopy conditions;With the increasing of canopy cover,the value of biomass allocation to leaf,specific leaf area and percentage of branching nodes increased,while the value of biomass allocation to root and number of roots decreased;Specific stem length and Specific rhizome length were lowest in Sg than in the other three canopy conditions.Branching intensity of rhizome was higher in Sg and Mg canopy conditions than in both Fu and Lg canopy conditions;In each canopy condition,the biomass and basal diameter of parent ramets were positively correlated with basal diameter of new shoots,the basal diameter of parent ramets was positively correlated with the biomass and diameter of spacers,the diameter of spacers was positively correlated with the basal diameter of new shoots.These results indicate that different canopy conditions significantly affect the clonal growth of F.denudata.The ramets adapt to varying canopy conditions by changing their morphological rather than quantitative characteristics.Sg is the relatively suitable canopy condition for F.denudate,under which the bamboos have faster growth rate.Different canopy conditions have effect on new shoots by affecting the size of their parent ramets.