Functional traits explain growth–mortality trade-offs in a mixed broadleaf-conifer forest in northeastern China

ABSTRACTResilience to abiotic stress is associated with a suite of functional traits related to defense and longevity. Stress tolerant plants are generally slow growing with extended leave lifespans and reduced allocation to reproduction. Resurrection plants are ideal systems to test for trade-offs associated with stress tolerance due to their extreme resiliency. While, growth defense trade-offs are well-characterized, few studies have tested for natural variation associated with tolerating the harshest environments. Here, we surveyed a suite of functional traits related to stress tolerance, leaf economics, and reproductive allocation in natural populations of the South African resurrection plant Myrothamnus flabellifolia. We selected three distinct field sites in South Africa ranging from mesic to xeric. Despite considerable environmental variation across the study area, M. flabellifolia plants were extremely and similarly stress tolerant at all sites. However, we detected notable variation in other life history and morphological traits. Plants in more mesic sites were larger, faster growing, and had more inflorescences. In contrast, plants from the most xeric sites appeared to invest more in persistence and defense, with lower growth rates and less reproductive allocation. Together, this suggests that desiccation tolerance is a binary trait in M. flabellifolia with little natural variation, but that other phenotypes are more labile. The trait syndromes exhibited by plants at the different study sites align with general expectations about growth defense tradeoffs associated with the colonization of extreme environments. We show that plants from the least stressful sites are more reproductive and faster growing, whereas plants from the most stressful sites were slower growing and less reproductive. These findings suggest that M. flabellifolia plants are finely tuned to their environment.

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Implementation constraints limit benefits of restoration treatments in mixed-conifer forests

International Journal of Wildland Fire ◽

10.1071/wf18141 ◽

2019 ◽

Vol 28 (7) ◽

pp. 495 ◽

Cited By ~ 6

Author(s):

Jamie M. Lydersen ◽

Brandon M. Collins ◽

Carolyn T. Hunsaker

Keyword(s):

Sierra Nevada ◽

Forest Structure ◽

Forest Restoration ◽

Tree Mortality ◽

Canopy Cover ◽

Basal Area ◽

Severe Drought ◽

Conifer Forest ◽

Mixed Conifer ◽

Trade Offs

Forest restoration treatments seek to increase resilience to wildfire and a changing climate while avoiding negative impacts to the ecosystem. The extent and intensity of treatments are often constrained by operational considerations and concerns over uncertainty in the trade-offs of addressing different management goals. The recent (2012–15) extreme drought in California, USA, resulted in widespread tree mortality, particularly in the southern Sierra Nevada, and provided an opportunity to assess the effects of restoration treatments on forest resilience to drought. We assessed changes in mixed-conifer forest structure following thinning and understorey burning at the Kings River Experimental Watersheds in the southern Sierra Nevada, and how treatments, topography and forest structure related to tree mortality in the recent drought. Treatments had negligible effect on basal area, tree density and canopy cover. Following the recent drought, average basal area mortality within the watersheds ranged from 5 to 26% across riparian areas and 12 to 44% across upland areas, with a range of 0 to 95% across all plots. Tree mortality was not significantly influenced by restoration treatments or topography. Our results suggest that the constraints common to many restoration treatments may limit their ability to mitigate the impacts of severe drought.

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Living the difference: alternative functional designs in five perennial herbs coexisting in a coastal dune environment

Functional Plant Biology ◽

10.1071/fp12392 ◽

2013 ◽

Vol 40 (11) ◽

pp. 1187 ◽

Cited By ~ 11

Author(s):

Raimundo Bermúdez ◽

Rubén Retuerto

Keyword(s):

Functional Traits ◽

Water Status ◽

Significant Degree ◽

Coastal Dune ◽

Stress Factors ◽

Limiting Factors ◽

Harsh Environments ◽

Limiting Similarity ◽

Environmental Filters ◽

Trade Offs

Ecological theory suggests that in harsh environments major abiotic stress factors may act as environmental filters, thereby reducing the range of possible plant strategies through environmental trait selection. This would lead to functional similarity of species coexisting in hostile environments. To test this prediction, we evaluated six functional leaf traits at three different times of year in five species coexisting in a coastal dune ecosystem. The functional traits examined were associated with water status and light interception and use – two of the most limiting factors that lead to stress in dune systems. Species differed in traits associated with light absorption, namely chlorophyll content, the vigour index NDVI, and the proportion of the light absorbed that is used in photochemistry (as expressed by the effective and maximum quantum yield of PSII and the photochemical reflectance index). For most of the traits, the relative performance of species depended significantly on time. This research revealed a significant divergence in functional traits of coexisting species, which does not conform to findings in other harsh environments where species tend to functional convergence. The data provide experimental support for the hypothesis that there is no single combination of traits for a given environment, but that alternative functional designs of similar fitness may evolve in the same environment as a result of complex interactions and trade-offs among traits. This suggests that factors claimed to promote divergence, such as limiting similarity and disturbance processes, may play an important role in structuring the dune community under study. The high variability in functional traits suggests a significant degree of functional diversity and highlights the importance of preserving the species composition of threatened coastal dune habitats in order to preserve distinctive functional processes that may be unique to the systems.

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Plant Functional Traits and Their Trade-offs in Response to Grazing:A Review

CHINESE BULLETIN OF BOTANY ◽

10.3724/sp.j.1259.2015.00159 ◽

2015 ◽

Vol 50 (2) ◽

pp. 159

Author(s):

Li Xiliang ◽

Liu Zhiying ◽

Hou Xiangyang ◽

Wu Xinhong ◽

Wang Zhen ◽

...

Keyword(s):

Functional Traits ◽

Plant Functional Traits ◽

Trade Offs

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Adaptation of epiphytic bryophytes in the understorey attributing to the correlations and trade-offs between functional traits

Journal of Bryology ◽

10.1080/03736687.2015.1120370 ◽

2016 ◽

Vol 38 (2) ◽

pp. 110-117 ◽

Cited By ~ 7

Author(s):

Xi Chen ◽

Wen-Yao Liu ◽

Liang Song ◽

Su Li ◽

Chuan-Sheng Wu ◽

...

Keyword(s):

Functional Traits ◽

Trade Offs

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Influence of functional traits on the demographic rates of 47 arboreal species in a tropical forest in northeastern Brazil

Journal of Environmental Analysis and Progress ◽

10.24221/jeap.2.1.2017.1023.23-35 ◽

2017 ◽

Vol 2 (1) ◽

pp. 23-35 ◽

Cited By ~ 1

Author(s):

Hian De Assis Monteiro ◽

André Luís Alves de Lima ◽

Ana Carolina Borges Lins-e-Silva ◽

Maria Amanda Menezes Silva ◽

Maria Jesus Nogueira Rodal

Keyword(s):

Tropical Forest ◽

Functional Traits ◽

Negative Relationship ◽

Principal Component ◽

Mortality Rates ◽

Northeastern Brazil ◽

Maximum Height ◽

Seed Shape ◽

Demographic Rates ◽

Trade Offs

Influence of functional traits on the demographic rates of 47 arboreal species in a tropical forest in northeastern Brazil. Based on the premise that species use different strategies for acquiring and maintaining resources, it is possible to identify their similarities as determined by particular trade-offs between traits, the present work examined the specific leaf area (SLA), basic wood density (BWD), maximum height (Hmax) and seed shape (SS) of 47 arboreal species in a moist semi-evergreen tropical forest in northeastern Brazil and investigated the influence of those traits on plant mortality rates (MR) and growth (BAG). BWD and Hmax were the best predictors of mortality rates. The factorial analysis explained 70.4% of the total variability, distributed among three factors composed of traits and rates. MR and Hmax were found to be more readily observed when orthogonally rotated by the varimax method, with the first factor explaining 26.9% of the variance. Cluster analyses and principal component analyses, whose matrices contained the variables MR, BAG, SLA, and Hmax for each species, confirmed the discriminant analysis and allowed the identification of four functional groups. The fact that some of the correlations encountered differed from previously published results (such as the negative relationship between maximum height and mortality) may reflect regional climatic seasonality or indicate that this strategy benefits plant species that reach the upper canopy and thus become well-established.

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Modeling light competition in the Amazon forest: the effects of high CO2 in functional diversity and biogeochemical cycle.

10.5194/egusphere-egu21-3514 ◽

2021 ◽

Author(s):

Bárbara Rocha Cardeli ◽

Bianca Fazio Rius ◽

Caio Fascina ◽

João Paulo Darela-Filho ◽

Gabriela Martins Sophia ◽

...

Keyword(s):

Climate Change ◽

Leaf Area ◽

Functional Diversity ◽

Functional Traits ◽

Environmental Conditions ◽

Climate Impacts ◽

Life Strategies ◽

Light Competition ◽

Trade Offs ◽

Competition For Light

The increase of CO2 concentrations implies direct and indirect (by changing climate) impacts on the terrestrial ecosystem. Several Dynamic Global Vegetation Models (DGVMs) have been developed to better understand the response of vegetation to climate change. However, the representation of plant diversity through a small set of Plant Functional Types (PFTs) adopted by the majority of DGVMs undermines their ability to represent functional diversity and fundamental interactions between these different life strategies of plants, like competition, which has been shown to be paramount in determining ecosystem functioning. Studies have shown that increasing CO2 concentration may determine the outcome of vegetation competition and, as a consequence, the ability to adapt to the environment, functional diversity, and community assembly mechanisms. Thus, the inclusion of competitive dynamics in these models becomes strategic to improve predictions and understanding the effects of climate change on vegetation and how it affects change in carbon fluxes and stocks in the community. In that sense, this project aims to contribute to the development of a light competition module within CAET&#202; model (CArbon and Ecosystem functional Trait Evaluation model) which involves the implementation of allometric relations between plant organs. As a trait-based model, CAET&#202; seeks to represent plant functional diversity in a less discrete way through the usage of variant values for functional traits. For this purpose, two key functional traits that are closely related to competition for light are employed as variants: wood density (WD) and specific leaf area (SLA). The main objective is to understand how light competition related to plant functional traits alters the response of Amazon plant communities under changing environmental conditions. As preliminary results, the algorithms containing the allometric and competition equations were developed outside the main model code and represent plant dynamics trade-offs between the variant functional traits and plant physiology and survivorship: WD relates to strategies of mortality and height growth. For example, high values of WD [1g/cm-3] are related to low heights [~30m.] and, low heights incur higher mortality rates; SLA relates to light competitive effect, Leaf Economics Spectrum, and LAI (leaf area index) determination, one of the most important parameters that determine the absorption of light by different life strategies. These trade-offs allow the representation of different plant life competition strategies. We expected that the light restriction for some functional strategies may incur a decrease in functional dominance and photosynthesis rate, consequently changing net primary productivity and after all the functional structure of the community. For functional diversity, it is expected changes in functional richness and functional divergence (related to the strength that competition exerts in the community) in order to favor strategies that better deal with the new environmental conditions simulated by CAET&#202; with increasing [CO2] to 600 ppmv, for example. Finally, it is expected that this approach may contribute to improving the representation of competition for light in DGVMs to more assertively obtain the effects of climate changes on vegetation and ecosystem dynamics. Final results will be obtained until the EGU Congress takes place.

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Trade-offs Between Succulent and Non-succulent Epiphytes Underlie Variation in Drought Tolerance and Avoidance

10.21203/rs.3.rs-899788/v1 ◽

2021 ◽

Author(s):

Sybil Gotsch ◽

Cameron B Williams ◽

Renee Bicaba ◽

Roxanne Cruz-de Hoyos ◽

Alexander Darby ◽

...

Keyword(s):

Drought Tolerance ◽

Functional Traits ◽

Carbon Allocation ◽

Cloud Forest ◽

Water Storage ◽

Drought Avoidance ◽

Trade Offs ◽

Epiphyte Communities ◽

Leaf Succulence ◽

The Impact

Abstract Epiphyte communities comprise important components of many forest ecosystems in terms of biomass and diversity, but little is known regarding trade-offs that underlie diversity and structure in these communities or the impact that microclimate has on epiphyte trait allocation. We measured 22 functional traits in vascular epiphyte communities across six sites that span a microclimatic gradient in a tropical montane cloud forest region in Costa Rica. We quantified traits that relate to carbon and nitrogen allocation, gas exchange, water storage, and drought tolerance. Functional diversity was high in all but the lowest elevation site where drought likely limits the success of certain species with particular trait combinations. For most traits, variation was explained by relationships with other traits (trait co-variance), rather than differences in microclimate across sites. Although there were significant differences in microclimate, epiphyte abundance, and diversity, we found substantial overlap in multivariate trait space across five of the sites. We found significant correlations between functional traits, many of which related to water storage, drought tolerance, and carbon allocation. This suite of trait correlations suggests that the epiphyte community has evolved functional strategies along a drought avoidance versus drought tolerance continuum where leaf succulence emerged as a pivotal overall trait.

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