Effects of rainfall pattern on the growth and fecundity of a dominant dune annual in a semi-arid ecosystem
Effects of rainfall pattern on the growth and fecundity of a dominant dune annual in a semi-arid ecosystem
复制标题
降雨模式对半干旱生态系统中优势沙丘一年生生长和繁殖力的影响
DOI：
10.1007/s11104-014-2366-4
复制
发表时间：
2015-04-01
期刊：
影响因子：
4.9
通讯作者：
Walck, Jeffrey L.
中科院分区：
文献类型：
--
作者：
Gao, Ruiru;Yang, Xuejun;Walck, Jeffrey L.
当前和未来降雨模式的变化——数量和频率——可能特别影响半干旱生态系统中的一年生植物。本研究的目的是探讨降雨模式的变化如何影响沙丘一年生植物的生长和繁殖力。以毛乌素沙地优势一年生植物沙米（Agriophyllum squarrosum）为研究对象，在近自然生境研究了5种降雨量和5种降雨频率梯度对沙米生长和繁殖的影响。降雨量和降雨频率对所有营养性状和生殖性状均有显著影响。随着降雨量的减少，高、生物量、种子数、种子质量和繁殖努力度降低，根冠比增加。除2个极端频率（1 d和120 d间隔）外，所有营养和生殖性状的值均随降雨频率的增加而增加。后代种子的发芽能力往往随着干旱程度的增加而增加，这表明可能存在母亲的影响。我们的研究表明，沙米的生长和繁殖力对降雨波动的可塑性响应使其能够在当前不可预测的环境中生存和繁殖，以及在半干旱地区气候变化预测的变异性增加。
Current and future changes in rainfall patterns - amount and frequency - may particularly impact annual plants in semi-arid ecosystems. The aim of this study was to investigate how changes in rainfall patterns affect the growth and fecundity of sand dune annuals.The effects of gradients in five rainfall amounts and five frequencies, based on historical and predicted values, on growth and fecundity of Agriophyllum squarrosum, a dominant annual in Mu Us Sandland, were examined in the near natural habitat.Rainfall amount and frequency significantly affected all vegetative and reproductive traits. With decreased amount of rainfall, height, biomass, seed number, seed mass and reproductive effort decreased, while root/shoot ratio increased. Except for the two extreme frequencies (1- and 120-day intervals), values of all vegetative and reproductive traits increased with the increase of rainfall frequencies. Germinability of offspring seeds tended to increase with increasing aridity, suggesting that a maternal effect may have been present.Our study shows that the plastic response in growth and fecundity of A. squarrosum to rainfall fluctuation allows the plant to survive and reproduce under current unpredictable environments as well as the increased variability predicted with climate change in semi-arid regions.