Exploring Plant Functional Diversity and Redundancy of Mediterranean High-Mountain Habitats in the Apennines

We analyzed plant functional diversity (FD) and redundancy (FR) in Mediterranean high-mountain communities to explore plant functional patterns and assembly rules. We focused on three above-ground plant traits: plant height (H), a good surrogate of competition for light strategies, and specific leaf area (SLA) and leaf dry matter content (LDMC), useful indicators of resource exploitation functional schemes. We used the georeferenced vegetation plots and field-measured plant functional traits of four widely spread vegetation types growing on screes, steep slopes, snowbeds and ridges, respectively. We calculated Rao’s FD and FR followed by analysis of standardized effect size, and compared FD and FR community values using ANOVA and the Tukey post hoc test. Assemblage rules varied across plant communities and traits. The High FRH registered on snowbeds and ridges is probably linked to climatic filtering processes, while the high FDH and low FDSLA and FDLDMC on steep slopes could be related with underlying competition mechanisms. The absence of FD patterns in scree vegetation pinpoint random assembly processes which are typical of highly unstable or disturbed ecosystems. Improved knowledge about the deterministic/stochastic processes shaping species coexistence on high mountain ecosystems should help researchers to understand and predict vegetation vulnerability to environmental changes.

Download Full-text

Alternative plant designs: consequences for community assembly and ecosystem functioning

Annals of Botany ◽

10.1093/aob/mcz180 ◽

2019 ◽

Author(s):

André Tavares Corrêa Dias ◽

Bruno H P Rosado ◽

Francesco de Bello ◽

Nuria Pistón ◽

Eduardo A de Mattos

Keyword(s):

Functional Diversity ◽

Ecosystem Functioning ◽

Species Coexistence ◽

Environmental Changes ◽

Plant Traits ◽

Multiple Traits ◽

Local Conditions ◽

Trade Offs ◽

And Function ◽

Alternative Designs

Abstract Background Alternative organism designs (i.e., the existence of distinct combinations of traits leading to the same function or performance) are a widespread phenomenon in nature and are considered an important mechanism driving the evolution and maintenance of species trait diversity. However, alternative designs are rarely considered when investigating assembly rules and species effects on ecosystem functioning, assuming that single traits trade-offs affect linearly species fitness and niche differentiation. Scope Here, we first review the concept of alternative designs, and the empirical evidence in plants indicating the importance of the complex effects of multiple traits on fitness. We then discuss how the potential decoupling of single traits with performance and function of species can compromise our ability to detect the mechanisms responsible for species coexistence and the effects of species on ecosystems. Placing traits in the continuum of organism integration level (i.e., traits hierarchically structured ranging from organ-level traits to whole-organism traits) can help in choosing traits more directly related to performance and function. Conclusions We conclude that alternative designs have important implications for the resulting trait patterning expected from different assembly processes. For instance, when only single trade-offs are considered, environmental filtering is expected to result in decreased functional diversity. Alternatively, it may result in increased functional diversity as an outcome of alternative strategies providing different solutions to local conditions and thus supporting coexistence. Additionally, alternative designs can result in higher stability of ecosystem functioning as species filtering due to environmental changes would not result in directional changes in (effect) trait values. Assessing the combined effects of multiple plant traits and their implications for plant functioning and functions will improve our mechanistic inferences about the functional significance of community trait patterning.

Download Full-text

Functional composition and diversity of leaf traits in subalpine versus alpine vegetation in the Apennines

AoB Plants ◽

10.1093/aobpla/plaa004 ◽

2020 ◽

Vol 12 (2) ◽

Cited By ~ 1

Author(s):

Angela Stanisci ◽

Alessandro Bricca ◽

Valentina Calabrese ◽

Maurizio Cutini ◽

Harald Pauli ◽

...

Keyword(s):

Functional Diversity ◽

Functional Traits ◽

Resource Use ◽

Leaf Traits ◽

Growing Season ◽

Plant Functional Traits ◽

High Mountain ◽

Maximum Height ◽

Dry Matter Content ◽

Functional Composition

Abstract Mediterranean high mountain grasslands are shaped by climatic stress and understanding their functional adaptations can contribute to better understanding ecosystems’ response to global change. The present work analyses the plant functional traits of high-elevation grasslands growing in Mediterranean limestone mountains to explore, at the community level, the presence of different plant strategies for resource use (conservative vs. acquisitive) and functional diversity syndromes (convergent or divergent). Thus, we compared the functional composition and diversity of the above-ground traits related to resource acquisition strategies of subalpine and alpine calcareous grasslands in the central Apennines, a mountain region characterized by a dry-summer Mediterranean climate. We used georeferenced vegetation plots and field-measured plant functional traits (plant maximum height, specific leaf area and leaf dry matter content) for the dominant species of two characteristic vegetation types: the subalpine Sesleria juncifolia community and the alpine Silene acaulis community. Both communities are of particular conservation concern and are rich in endemic species for which plant functional traits are measured here for the first time. We analysed the functional composition and diversity using the community-weighted mean trait index and the functional diversity using Rao’s function, and we assessed how much the observed pattern deviated from a random distribution by calculating the respective standardized effect sizes. The results highlighted that an acquisitive resource use strategy and relatively higher functional diversity of leaf traits prevail in the alpine S. acaulis community, optimizing a rapid carbon gain, which would help overcome the constraints exerted by the short growing season. The divergent functional strategy underlines the co-occurrence of different leaf traits in the alpine grasslands, which shows good adaptation to a microhabitat-rich environment. Conversely, in the subalpine S. juncifolia grassland, a conservative resource use strategy and relatively lower functional diversity of the leaf traits are likely related to a high level resistance to aridity over a longer growing season. Our outcomes indicate the preadaptation strategy of the subalpine S. juncifolia grassland to shift upwards to the alpine zone that will become warmer and drier as a result of anthropogenic climate change.

Download Full-text

Direct and indirect facilitation affect community productivity through changes in functional diversity in an alpine system

Annals of Botany ◽

10.1093/aob/mcaa170 ◽

2020 ◽

Author(s):

Xiangtai Wang ◽

Richard Michalet ◽

Lihua Meng ◽

Xianhui Zhou ◽

Shuyan Chen ◽

...

Keyword(s):

Functional Diversity ◽

Structural Equation ◽

Local Community ◽

Plant Traits ◽

Taxonomic Diversity ◽

Lateral Spread ◽

The Tibetan Plateau ◽

Dry Matter Content ◽

Primary Role ◽

Indirect Facilitation

Abstract Background and Aims Facilitation is an important ecological process for plant community structure and functional composition. Although direct facilitation has accrued most of the evidence so far, indirect facilitation is ubiquitous in nature and it has an enormous potential to explain community structuring. In this study, we assess the effect of direct and indirect facilitation on community productivity via taxonomic and functional diversity. Methods In an alpine community on the Tibetan Plateau, we manipulated the presence of the shrub Dasiphora fruticosa and graminoids in a fenced meadow and a grazed meadow to quantify the effects of direct and indirect facilitation. We measured four plant traits: height, lateral spread, specific leaf area (SLA) and leaf dry matter content (LDMC) of forbs; calculated two metrics of functional diversity [range of trait and community-weighted mean (CWM) of trait]; and assessed the responses of functional diversity to shrub facilitation. We used structural equation modelling to explore how shrubs directly and indirectly drove community productivity via taxonomic diversity and functional diversity. Key Results We found stronger effects from herbivore-mediated indirect facilitation than direct facilitation on productivity and taxonomic diversity, regardless of the presence of graminoids. For functional diversity, the range and CWM of height and SLA, rather than lateral spread and LDMC, generally increased due to direct and indirect facilitation. Moreover, we found that the range of traits played a primary role over taxonomic diversity and CWM of traits in terms of shrub effects on community productivity. Conclusions Our study reveals that the mechanism of shrub direct and indirect facilitation of community productivity in this alpine community is expanding the realized niche (i.e. expanding range of traits). Our findings indicate that facilitators might increase trait dispersion in the local community, which could alleviate the effect of environmental filters on trait values in harsh environments, thereby contributing to ecosystem functioning.

Download Full-text

Linking functional diversity to ecological indicators: A tool to predict the anthropogenic effects on ecosystem functioning

Environmental Reviews ◽

10.1139/er-2021-0093 ◽

2022 ◽

Author(s):

Leticia Bonilla-Valencia ◽

Silvia Castillo-Argüero ◽

José Alejandro Zavala-Hurtado ◽

Francisco Javier Espinosa-García ◽

Roberto Lindig-Cisneros ◽

...

Keyword(s):

Functional Diversity ◽

Plant Traits ◽

Functional Divergence ◽

Seed Mass ◽

Ecosystem Processes ◽

Ecological Indicators ◽

Ecological Indicator ◽

Dry Matter Content ◽

Weed Species ◽

Functional Richness

Functional diversity is related to the maintenance of processes and functions in ecosystems. However, there is a lack of a conceptual framework that highlights the application of functional diversity as an ecological indicator. Therefore, we present a new initiative for motivating the development of ecological indicators based on functional diversity. We are interested in showing the challenges and solutions associated with these indicators. We integrated species assemblage theories and literature reviews. We considered plant traits related to ecosystem processes and functions (specific leaf area, leaf dry matter content, wood density, phenology, and seed mass) to show the application of a selection of functional diversity metrics that can be used as ecological indicators (i.e., Community Weighted-Mean, Functional Divergence, Functional Richness and Functional Evenness). We caution that functional diversity as an ecological indicator can be misinterpreted if species composition is unknown. Functional diversity values can be overrepresented by weed species (species established in disturbed sites) and do not maintain original processes and functions in ecosystems. Therefore, we searched for evidence to demonstrate that weed species are ecological indicators of functional diversity changes. We found support for two hypotheses that explain the effect of weed species on ecosystem function: functional homogenization and functional transformation. Likewise, we showed the application of some tools that can help study the anthropogenic effect on functional indicators. This review shows that the paradigm of addressing the effects of disturbances on ecosystem processes by using functional diversity as an ecological indicator can improve environmental evaluation, particularly in areas affected by human activities.

Download Full-text

Grazing promotes plant functional diversity in alpine meadows on the Qinghai-Tibetan Plateau

The Rangeland Journal ◽

10.1071/rj18091 ◽

2019 ◽

Vol 41 (1) ◽

pp. 73 ◽

Cited By ~ 3

Author(s):

Yu Li ◽

Shikui Dong ◽

Qingzhu Gao ◽

Yong Zhang ◽

Shiliang Liu ◽

...

Keyword(s):

Leaf Area ◽

Functional Diversity ◽

Plant Traits ◽

Leaf Nitrogen Content ◽

Alpine Plant ◽

Rotational Grazing ◽

Continuous Grazing ◽

Functional Richness ◽

Plant Functional Diversity ◽

Kobresia Pygmaea

Grazing exclosures and rotational grazing have been extensively applied to prevent grassland degradation and to restore grassland ecosystem function and services. The mechanisms associated with changes in alpine plant traits, and functional diversity under different grazing regimes have not been deeply explored. We examined the variations of plant leaf traits and functional diversity of an alpine meadow under different grazing regimes in a 3-year experiment. The results showed, after 3 years of yak grazing, that the coverage of Stipa capillata increased, whereas that of Kobresia pygmaea decreased under grazing exclosure. Stipa capillata had a lower ratio of leaf nitrogen content to phosphorus content (N:P) under grazing exclosure than under rotational grazing and continuous grazing, whereas Kobresia pygmaea showed no significant differences among grazing treatments. Among grazing regimes, the specific leaf area (SLA) of Stipa capillata was similar, whereas that of Kobresia pygmaea was higher under grazing exclosure. At the interspecific level, leaf area and weight were negatively correlated with SLA, whereas leaf carbon (C) content, leaf N content, leaf C:P and leaf N:P were negatively related to leaf P content and leaf C:N. These findings indicated that growth-defence trade-off strategies might lead to variations in plant traits and coverage. Large-leaved species, due to high maintenance costs, were less commonly distributed in the community, and they were better defended and unpalatable to yaks due to lower SLA, this formed the species coverage distribution pattern of the community. Various N and P utilisation efficiency of different species indicated diverse economic resources utilisation strategies might be due to niche differentiation in the community. Plots that had been excluded from grazing had the lowest functional richness, evenness, and divergence. Rotational and continuous grazing were equivalent in promoting alpine plant functional diversity.

Download Full-text

Responses of Benthic Macroinvertebrate Communities of Two Tropical, High-Mountain Lakes to Climate Change and Deacidification

Diversity ◽

10.3390/d13060243 ◽

2021 ◽

Vol 13 (6) ◽

pp. 243

Author(s):

Javier Alcocer ◽

Luis A. Oseguera ◽

Diana Ibarra-Morales ◽

Elva Escobar ◽

Lucero García-Cid

Keyword(s):

Climate Change ◽

Species Richness ◽

Water Temperature ◽

Water Level ◽

Environmental Changes ◽

Mountain Lakes ◽

High Mountain ◽

Macroinvertebrate Communities ◽

High Mountain Lakes ◽

La Luna

High-mountain lakes are among the most comparable ecosystems globally and recognized sentinels of global change. The present study pursued to identify how the benthic macroinvertebrates (BMI) communities of two tropical, high mountain lakes, El Sol and La Luna, Central Mexico, have been affected by global/regional environmental pressures. We compared the environmental characteristics and the BMI communities between 2000–2001 and 2017–2018. We identified three principal environmental changes (the air and water temperature increased, the lakes’ water level declined, and the pH augmented and became more variable), and four principal ecological changes in the BMI communities [a species richness reduction (7 to 4), a composition change, and a dominant species replacement all of them in Lake El Sol, a species richness increase (2 to 4) in Lake La Luna, and a drastic reduction in density (38% and 90%) and biomass (92%) in both lakes]. The air and water temperature increased 0.5 °C, and lakes water level declined 1.5 m, all suggesting an outcome of climate change. Contrarily to the expected acidification associated with acid precipitation, both lakes deacidified, and the annual pH fluctuation augmented. The causes of the deacidification and the deleterious impacts on the BMI communities remained to be identified.

Download Full-text

Climate change drives mountain butterflies towards the summits

Scientific Reports ◽

10.1038/s41598-021-93826-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Dennis Rödder ◽

Thomas Schmitt ◽

Patrick Gros ◽

Werner Ulrich ◽

Jan Christian Habel

Keyword(s):

Climate Change ◽

Life History ◽

Climate Warming ◽

Environmental Changes ◽

Range Shifts ◽

Solar Irradiation ◽

High Mountain ◽

Detailed Knowledge ◽

Annual Range

AbstractClimate change impacts biodiversity and is driving range shifts of species and populations across the globe. To understand the effects of climate warming on biota, long-term observations of the occurrence of species and detailed knowledge on their ecology and life-history is crucial. Mountain species particularly suffer under climate warming and often respond to environmental changes by altitudinal range shifts. We assessed long-term distribution trends of mountain butterflies across the eastern Alps and calculated species’ specific annual range shifts based on field observations and species distribution models, counterbalancing the potential drawbacks of both approaches. We also compiled details on the ecology, behaviour and life-history, and the climate niche of each species assessed. We found that the highest altitudinal maxima were observed recently in the majority of cases, while the lowest altitudes of observations were recorded before 1980. Mobile and generalist species with a broad ecological amplitude tended to move uphill more than specialist and sedentary species. As main drivers we identified climatic conditions and topographic variables, such as insolation and solar irradiation. This study provides important evidence for responses of high mountain taxa to rapid climate change. Our study underlines the advantage of combining historical surveys and museum collection data with cutting-edge analyses.

Download Full-text

Functional diversity alters the effects of a pulse perturbation on the dynamics of tritrophic food webs

10.1101/2021.03.22.436420 ◽

2021 ◽

Author(s):

Ruben Ceulemans ◽

Laurie Anne Myriam Wojcik ◽

Ursula Gaedke

Keyword(s):

Food Web ◽

Food Webs ◽

Functional Diversity ◽

Feedback Loop ◽

Environmental Changes ◽

Biodiversity Loss ◽

Trophic Levels ◽

Nutrient Pulse ◽

Trade Offs ◽

Food Web Model

Biodiversity decline causes a loss of functional diversity, which threatens ecosystems through a dangerous feedback loop: this loss may hamper ecosystems' ability to buffer environmental changes, leading to further biodiversity losses. In this context, the increasing frequency of climate and human-induced excessive loading of nutrients causes major problems in aquatic systems. Previous studies investigating how functional diversity influences the response of food webs to disturbances have mainly considered systems with at most two functionally diverse trophic levels. Here, we investigate the effects of a nutrient pulse on the resistance, resilience and elasticity of a tritrophic---and thus more realistic---plankton food web model depending on its functional diversity. We compare a non-adaptive food chain with no diversity to a highly diverse food web with three adaptive trophic levels. The species fitness differences are balanced through trade-offs between defense/growth rate for prey and selectivity/half-saturation constant for predators. We showed that the resistance, resilience and elasticity of tritrophic food webs decreased with larger perturbation sizes and depended on the state of the system when the perturbation occured. Importantly, we found that a more diverse food web was generally more resistant, resilient, and elastic. Particularly, functional diversity dampened the probability of a regime shift towards a non-desirable alternative state. In addition, despite the complex influence of the shape and type of the dynamical attractors, the basal-intermediate interaction determined the robustness against a nutrient pulse. This relationship was strongly influenced by the diversity present and the third trophic level. Overall, using a food web model of realistic complexity, this study confirms the destructive potential of the positive feedback loop between biodiversity loss and robustness, by uncovering mechanisms leading to a decrease in resistance, resilience and elasticity as functional diversity declines.

Download Full-text