文献类型：期刊文献

英文题名：A trade-off between primary and secondary seed dispersal by wind

作者：Zhu, Jinlei[1] Liu, Minghu[2] Xin, Zhiming[2] Liu, Zhimin[3] Schurr, Frank M.[1]

第一作者：Zhu, Jinlei

通信作者：Zhu, JL[1]

机构：[1]Univ Hohenheim, Inst Landscape & Plant Ecol, D-70599 Stuttgart, Germany;[2]Chinese Acad Forestry, Expt Ctr Desert Forestry, Dengkou 015200, Peoples R China;[3]Chinese Acad Sci, Inst Appl Ecol, Shenyang 110016, Liaoning, Peoples R China

年份：2019

卷号：220

期号：4-5

起止页码：541-552

外文期刊名：PLANT ECOLOGY

收录：;Scopus(收录号：2-s2.0-85064565182);WOS:【SCI-EXPANDED(收录号:WOS:000464898600011)】；

基金：Thanks to Yaru Huang and Batu Gegen for assistance with seed collection, to Baoqing Liu, Xinle Li, Yingbin Ma and Yingming Zhao for assistance with dispersal experiments, and to two anonymous reviewers for helpful comments on the manuscript. The work was supported by the National Natural Science Foundation of China (NSFC) [41571270], the Sino-German (CSC-DAAD) Postdoc Scholarship Program [57165010], and the German Research Foundation (DFG) [DynNiche, SCHU 2259/5-1].

语种：英文

外文关键词：Anemochory; Diaspore; Dispersal evolution; Experimental ecology; Functional traits; Plant dispersal

摘要：The seeds of most plant species are dispersed by multiple mechanisms. Whether functional traits mediate positive correlations or negative correlations (trade-offs) between different dispersal mechanisms has important consequences for ecological and evolutionary dynamics. We investigate how traits affect wind-driven seed dispersal through the air and across the ground (primary and secondary wind dispersal, respectively). We hypothesized that primary and secondary wind dispersal were positively correlated because they should both decrease with the wing loading of seeds. We test this hypothesis with wind-tunnel experiments using different seed morphologies of Zygophyllum xanthoxylon (heterocarpous) and Calligonum species. We measured primary dispersal distance at varying wind speeds and release heights, and quantified secondary dispersal potential as the threshold wind speed for seed movement on four ground surfaces. Contrary to our expectation, we found a context-dependent trade-off between primary and secondary wind dispersal. The smoother the ground surface, the stronger this trade-off becomes. The trade-off results from a positive relationship between wing loading and the ratio of vertical to horizontal seed projection (v/h-ratio): an increasing v/h-ratio not only promotes secondary dispersal on smooth surfaces by increasing wind interception of seeds, but also decreases primary dispersal distance by increasing wing loading and terminal velocity of seeds. The trade-off contradicts the widespread assumption of a positive correlation between primary and secondary dispersal. A simple classification into poorly and well-dispersed seeds is thus not possible. The trade-off may affect dynamics of succession and the expansion of pioneer vegetation, while potentially slowing down evolutionary responses to selection on seed dispersal.