光温变化对岷山3种大熊猫主食竹克隆生长与可食性的影响

The decrease in body cloudage can lead to the significant increase of total radiation in eastern Qinghai-Tibet Plateau. Minshan Mountain, located in the eastern Qinghai-Tibet Plateau, is the one of sensitive zone to climate change. The panda's habitat area, in Minshan Mountains, accounts for 44.3% of the total panda's habitat area in China. The total area and grazed frequency of Fargesia rufa, F. denudata and F. nitida account for 60% and 75% in Minshan mountain, respectively. The growth and edibility of the above-mentioned three dwarf bamboos directly influence panda survival and reproduction. The change of forest structure and canopy caused by the logging and earthquake can lead to the increase of light density and warming in understory. The above-mentioned abiotic factors have potential effects on the growth, palatability and nutrition value of dwarf bamboo. However, the effects of increase in light density and warming on clonal growth and edibility of panda's food bamboo is unknown, thereby it affects restoration model and management of the degenerative panda habitat.Based on the above-mentioned questiion, the fixed sample observation, in situ, and simulate change of light density and temperature, were applied in this proposal. The responses and adaptation of clonal growth and edibility in three dwarf bamboo to the change of light density and warning will be investigated in this proposal. The results will play an important scientific and practical role in habitat vegetation restoration, corridor construction and evaluation of nutritional value for panda's food bamboo.

青藏高原东部的主体云量显著下降将导致到达地面的总辐射增加。岷山山系地处青藏高原东部，是气候变化较为敏感的区域之一。该山系大熊猫栖息地面积占总栖息地面积的44.3%，青川箭竹、缺苞箭竹和华西箭竹分布面积和取食率分别占60%和75%。以上3种大熊猫主食竹的生长发育和可食性直接影响大熊猫的生存和繁衍。大熊猫主食竹的生长发育、适口性和营养价值不仅受到因采伐和地震造成林冠覆盖降低而形成的强光照和增温的控制，同时也受到全球气候变暖的影响。光温变化对大熊猫主食竹的克隆生长和可食性的调控研究鲜有报道，从而影响了大熊猫栖息地恢复和管理工作。本项目拟采用原位固定样方观测和模拟光温变化控制实验相结合的方法，从大熊猫主食竹的生长发育、适口性和营养成分等方面来研究大熊猫主食竹的克隆生长和可食性对光温变化的响应与适应，研究结果对大熊猫退化栖息地植被恢复、走廊带建设以及主食竹营养价值评价等具有重要的科学与实践意义。

通过本项项目的实施，建立了大熊猫主食竹野外原位观测和控制实验研究平台。在项目执行期内，与本项目研究内容完全相关的科研论文1篇被《生态学报》录用。参与项目的2名博士生已顺利毕业。新参与本项目的硕士研究生有3名，其中2名硕士研究生的硕士毕业论文研究内容是本项目研究内容的一部分。项目参与者赵红霞副研究员成功申请国家自然科学基金面上项目。箭竹幼嫩部位的单宁含量低，其含量顺序是竹笋＜竹杆＜叶、≥2年生克隆分株的叶单宁含量＞1年生克隆分株；箭竹总酚含量顺序是竹笋＜竹杆＜叶，其中竹笋最低，多年生竹叶最高。同一海拔箭竹的粗蛋白和粗脂肪含量均表现为叶>笋>秆，且笋、秆和叶的营养成分含量有显著差异 (P <0.05)；粗蛋白和氨基酸总量随海拔升高而显著增加 (P <0.05)，而对粗脂肪和粗纤维的影响不显著（P >0.05)；除笋中苏氨酸、甘氨酸、半胱氨酸，秆中丝氨酸、蛋氨酸以及叶中半胱氨酸外，海拔对其余氨基酸含量均有显著影响 (P <0.05)；海拔对粗蛋白/粗脂肪、粗蛋白/粗纤维有显著影响 (P <0.05)，而海拔对纤维素/粗纤维、粗脂肪/粗纤维的影响不显著 (P >0.05)。缺苞箭竹叶、笋的营养成分含量明显高于秆；高海拔有利于缺苞箭竹各器官粗蛋白和氨基酸的积累，不利于粗纤维的积累，这可能使大熊猫的取食选择发生改变，更倾向于取食高海拔的笋和叶。