Experimental Warming Enhances Effects of Eelgrass Genetic Diversity Via Temperature-Induced Niche Differentiation
- PDF / 1,456,006 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 43 Downloads / 166 Views
SPECIAL ISSUE: SEAGRASSES TRIBUTE TO SUSAN WILLIAMS
Experimental Warming Enhances Effects of Eelgrass Genetic Diversity Via Temperature-Induced Niche Differentiation Katherine DuBois 1,2
&
Susan L. Williams 1,2 & John J. Stachowicz 2
Received: 17 May 2020 / Revised: 21 August 2020 / Accepted: 28 August 2020 # Coastal and Estuarine Research Federation 2020
Abstract Genetic diversity within coastal foundation species can enhance species and ecosystem resilience to ocean warming and marine heatwaves. However, the effects of diversity on ecosystem function are often context-dependent and mechanisms underpinning, such contingency, remain poorly understood. To test the relationship between genetic diversity and resilience to warming in a coastal foundation species, we planted eelgrass (Zostera marina) pots at two levels of genotypic richness (1 genotype monocultures or 4 genotype mixtures) and exposed these pots to warming events of different frequencies (sustained or alternating) in mesocosms for four months (mid-summer to late fall). Our results revealed that in monocultures warming reduced pot biomass by 15.8% but warming led to overyielding in mixtures by 33.3%. In contrast, mixture biomass at control temperatures underyielded by 13.2%. Overyielding of mixtures during sustained warming was driven by positive complementarity, which appears to be the result of warming-induced shifts in the relative performance of genotypes over time. We propose that high temperature stress created a tradeoff, such that some genotypes experienced greater photoinhibiton during mid-summer while other genotypes were light limited during the late fall. Thus, seasonal differences in temperature and light conditions in the warming treatment generated asynchrony in genotype peak performance, freed genotypes from competitive interactions, and allowed overyielding via complementarity to occur. While we demonstrate that the effects of diversity on ecosystem function depend on environmental context as well as trait variation among genotypes, our results underscore that maintaining or restoring genetic diversity could dramatically improve the resilience of coastal foundation species to future ocean warming. Keywords Biodiversity-ecosystem functioning . Complementarity . Niche differentiation . Environmental heterogeneity . Ocean warming . Zostera marina
Introduction The conservation of coastal ecosystems depends on management and restoration practices that reinforce ecosystem Susan L. Williams is deceased. Communicated by Mark J. Brush Electronic supplementary material The online version of this article (https://doi.org/10.1007/s12237-020-00827-9) contains supplementary material, which is available to authorized users. * Katherine DuBois [email protected] 1
Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923, USA
2
Department of Evolution and Ecology, University of California Davis, Davis, CA 95616, USA
resilience (i.e., the ability to resist and recover from disturbance, sensu Bernhardt and Leslie 2013). Main
Data Loading...
