Schoenoplectus salinity tolerance and regional environmental records

Evidence is mounting that climate-driven shifts in environmental conditions can elicit organismal evolution, yet there are sparingly few long-term records that document the tempo and progression of responses, particularly for plants capable of transforming ecosystems. In this study, we ‘resurrected’ cohorts of a foundational coastal marsh sedge (Schoenoplectus americanus) from a time-stratified seed bank to reconstruct a century-long record of heritable variation in response to salinity exposure. Common-garden experiments revealed that S. americanus exhibits heritable variation in phenotypic traits and biomass-based measures of salinity tolerance. We found that responses to salinity exposure differed among the revived cohorts, with plants from the early 20th century exhibiting greater salinity tolerance than those from the mid to late 20th century. Fluctuations in salinity tolerance could reflect stochastic variation but a congruent record of genotypic variation points to the alternativ...越来越多的证据表明，气候驱动的环境条件变化可引发生物演化，但能够记录演化响应的速率与进程的长期记录却寥寥无几，对于具备生态系统改造能力的植物而言更是如此。在本研究中，我们从分层时间序列种子库中复活了优势滨海莎草（Schoenoplectus americanus）的多个世代群体，以重建为期百年的、响应盐分胁迫的可遗传变异记录。同质园实验结果显示，美洲蔗草（S. americanus）在表型性状以及基于生物量的盐分耐受性指标上均存在可遗传变异。我们发现，不同复活世代群体对盐分胁迫的响应存在差异：20世纪早期的植株相较于20世纪中后期植株，表现出更强的盐分耐受性。盐分耐受性的波动可能源于随机变异，但与之匹配的基因型变异记录则指向另一种可能性……