摘要
研究树木叶片解剖结构对气候暖化的响应有助于深入认识树木对气候变化的适应机制.本文采用同质园互置试验模拟气候暖化,研究了兴安落叶松11个种源叶解剖结构对气候暖化的响应.结果表明:暖化处理后,兴安落叶松叶片厚度、上表皮叶肉厚度、下表皮叶肉厚度、内皮层厚度、维管束直径、转输组织厚度和叶肉厚度比例均显著增大,上表皮厚度和表皮厚度比例均显著减小.叶肉厚度与叶绿素含量和最大净光合速率均存在显著正相关关系.叶片厚度、上表皮叶肉厚度、下表皮叶肉厚度、内皮层厚度、维管束直径、转输组织厚度、上表皮厚度、叶肉厚度比例和表皮厚度比例对暖化处理的响应存在明显的种源差异,叶片厚度、上表皮叶肉厚度、下表皮叶肉厚度、转输组织厚度和叶肉厚度比例的暖化效应随种子来源地干旱指数的增大而减小,而上表皮厚度和表皮厚度比例的暖化效应随种子来源地干旱指数的增大而增大.暖化处理增大了收益型组织(叶肉)的厚度及其比例,减小了防御型组织(表皮)的厚度及比例,并且这种改变因种源的不同而存在差异.兴安落叶松可以通过调整叶片解剖结构适应气候暖化,来自于干旱指数较大地点的种源调整能力较弱.
Abstract
Exploring the response of leaf anatomical structure to climate warming is helpful for understanding the adaptive mechanisms of trees to climate change.We conducted a warming experiment by transplanting seedlings of Larix gmelinii from 11 provenances to two common gardens,and examined the response of leaf anatomical structure to climate warming.The results showed that warming significantly increased leaf thickness(TL),upper epidermal mesophyll thickness(TUEM),lower epidermal mesophyll thickness(TLEM),endodermal thickness(TE),vascular bundle diameter(DVB),transfer tissue thickness(TTT),and the percentage of mesophyll thickness to TL(PMT),and significantly decreased the upper epidermal thickness(TUE)and the percentage of epidermal thickness to TL(PE).The mesophyll thickness was positively associated with chlorophyll concentration and maximum net photosyn-thetic rate.The responses of TL,TUEM,TLEM,TE,DVB,TTT,TUE,PMT and PE to warming differed among all the provenances.As the aridity index of the original site increased,the magnitude of the warming treatment's effect decreased for TL,TUEM,TLEM,TTT and PMT,and increased for TUE and PE.Warming increased the thickness and proportion of profit tissue(e.g.,mesophyll)and decreased the thickness and proportion of defensive tissue(e.g.,epidermis),and those changes varied among provenances.L.gmelinii could adapt to climate warming by adjusting leaf anatomical structure,and this ability was weak for trees from provenance with high aridity index.
基金项目
国家重点研发计划(2021YFD220040107)
国家级大学生创新训练项目(202210225130)
国家科技期刊平台
NSTL
万方数据