芦芽山不同海拔白杄非结构性碳水化合物含量动态  

Variations of non-structural carbohydrate concentration of Picea meyeri at different elevations of Luya Mountain,China

作　　者：王彪[1,2] 江源[1,2,3] 王明昌[1,2] 董满宇[1,2] 章异平[1,2] 

机构地区：[1]北京师范大学中药资源保护与利用北京市重点实验室,北京100875 [2]北京师范大学资源学院,北京100875 [3]北京师范大学地表过程与资源生态国家重点实验室,北京100875

出　　处：《植物生态学报》2015年第7期746-752,共7页Chinese Journal of Plant Ecology

基　　金：国家自然科学基金(41171067和41271059);中央高校基本科研业务经费专项资金(2013NT63)

摘　　要：高山林线对环境变化具有高度的敏感性,但林线形成机制仍然没有明确的结论。为了检验高山林线形成是由碳限制还是生长限制决定,并探讨林线树种适应高山环境的生理生态机制,选择山西省吕梁山脉北端芦芽山,沿3个海拔梯度测定了林线树种白杄(Picea meyeri)各组织非结构性碳水化合物(NSC)及其组分含量。结果表明:白杄总体及各组织NSC含量均随海拔升高而增加,林线树木不存在碳限制;白杄NSC源、汇均随海拔升高而增加,源-汇比在3个海拔之间没有差异,表明源-汇平衡关系对海拔的适应性,林线树木碳源活动没有受到限制;各组织中可溶性糖与淀粉的比值随海拔升高呈增大趋势,说明树木生长的环境越寒冷,树木组织中表现出越明显的保护策略,也可能暗示林线区域的树木更多地受到生长限制。研究结果在一定程度上支持"生长限制"假说。Aims The alpine timberline is highly sensitive to environmental changes, although the mechanism controlling timberline formation is still inconclusive. Our objectives in this study were to test whether the alpine timberline formation is determined by carbon limitation or growth limitation, and explore physiological and ecologi- cal mechanisms of timberline tree species adapting to alpine environments. We examined the concentrations of the overall nonstructural carbohydrates （NSC） and tissues NSC of Picea meyeri at the end of growing season and in three elevations （low, medium and timberline） along an altitudinal gradient on the north slope of Luya Mountain, Shanxi, China. Methods We collected samples of leaf, stem and fine root tissues of P. meyeri on September 15, 2013. The total soluble sugar concentration of plant tissue was measured by an anthrone-sulfuric acid colorimetric method, and starch was extracted by a perchloric acid method. Important findings The overall NSC and tissues NSC increased significantly with elevation, suggesting that there was no carbon limitation at the alpine timberline. The NSC source and sink are all increased significantly with elevation, and there is no significant difference in the source-sink ratio among three elevations, indicating an adaptation of source-sink balances to altitudes and no restriction of carbon source activity in timberline trees. The ratio of sugar to starch in tissues showed an increasing trend with elevation, which suggests that the colder the environment was, the stronger the protective strategy adopted in plant tissues through resource investments, im- plying more growth limitation in trees near timberlines, The research results appear to support the ＂growth limit＂ hypothesis to some degree.

关 键 词：海拔 非结构性碳水化合物 源.汇平衡 可溶性糖与淀粉比值 白杄 林线 

分 类 号：S718.4[农业科学—林学]