Functional Divergence between Várzea and Igapó Forests: A Study of Functional Trait Diversity in the Colombian Orinoco Basin

Research Highlights: Functional diversity studies help to better understand how organisms respond to different environmental conditions. Conditions in tropical flooded forests are highly variable, including levels of nutrient availability, pH, and flood depth, but few studies have explored the impact of variation in these factors on plant functional diversity. Background and Objectives: In the Orinoco basin, as in the Amazon, floodplain forests have been classified into várzea (white-water rivers, with nutrient-rich soils) and igapó (black-water rivers, associated with nutrient-poor soils). We evaluated the functional diversity of plant species in várzea and igapó, as well as the influence of external and internal filters on the plant community assembly of each forest type, and compared our results with studies in the Amazon basin. Materials and Methods: Six functional traits were recorded in the várzea and igapó forests of the Colombian Orinoco basin (one-hectare plot for each forest type, with no replicates). We evaluated plant species diversity (richness, Fisher’s α, Shannon and Simpson indices), as well as functional diversity (functional richness, functional evenness, functional divergence, and functional dispersion) and the influence of external and internal filters, based on a comparison of variance at different organizational levels. Results: A high functional differentiation between várzea and igapó was found, as well as a high functional divergence within each forest type. We also observed a greater influence of internal filters on the community assembly of both forest types, compared to external filters. Functional traits such as wood density and leaf dry matter content, showed the same patterns as the várzea and igapó forests in the Amazon. Conclusions: Despite the low taxonomic and functional richness, there is high functional divergence within flooded forests. We also show that in forests under stress (e.g., from flooding), internal filters can be key in assembling communities and promote high functional divergence. Given that the functional diversity of the várzea and igapó in the Orinoco is largely unexplored, we highlight the need for more research for the effective conservation of these flooded forests.

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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.

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Community-weighted mean traits but not functional diversity determine the changes in soil properties during wetland drying on the Tibetan Plateau

Solid Earth ◽

10.5194/se-8-137-2017 ◽

2017 ◽

Vol 8 (1) ◽

pp. 137-147 ◽

Cited By ~ 7

Author(s):

Wei Li ◽

Howard E. Epstein ◽

Zhongming Wen ◽

Jie Zhao ◽

Jingwei Jin ◽

...

Keyword(s):

Tibetan Plateau ◽

Soil Properties ◽

Leaf Area ◽

Functional Diversity ◽

Functional Divergence ◽

The Tibetan Plateau ◽

Dry Matter Content ◽

Weighted Mean ◽

Functional Richness ◽

Community Weighted Mean

Abstract. Climate change and human activities have caused a shift in vegetation composition and soil biogeochemical cycles of alpine wetlands on the Tibetan Plateau. The primary goal of this study was to test for associations between community-weighted mean (CWM) traits, functional diversity, and soil properties during wetland drying. We collected soil samples and investigated the aboveground vegetation in swamp, swamp meadow, and typical meadow environments. Four CWM trait values (specific leaf area is SLA, leaf dry matter content is LDMC, leaf area is LA, and mature plant height is MPH) for 42 common species were measured across the three habitats; three components of functional diversity (functional richness, functional evenness, and functional divergence) were also quantified at these sites. Our results showed that the drying of the wetland dramatically altered plant community and soil properties. There was a significant correlation between CWM of traits and soil properties, but not a significant correlation between functional diversity and soil properties. Our results further showed that CWM-LA, CWM-SLA, and CWM-LDMC had positive correlations with soil readily available nutrients (available nitrogen, AN; available phosphorus, AP), but negative correlations with total soil nutrients (soil organic carbon is SOC, total nitrogen is TN, and total phosphorus is TP). Our study demonstrated that simple, quantitative plant functional traits, but not functional diversity, are directly related to soil C and N properties, and they likely play an important role in plant–soil interactions. Our results also suggest that functional identity of species may be more important than functional diversity in influencing ecosystem processes during wetland drying.

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Functional Diversity Changes after Selective Thinning in a Tropical Mountain Forest in Southern Ecuador

Diversity ◽

10.3390/d12060256 ◽

2020 ◽

Vol 12 (6) ◽

pp. 256

Author(s):

Omar Cabrera ◽

Patrick Hildebrandt ◽

Bernd Stimm ◽

Sven Günter ◽

Andreas Fries ◽

...

Keyword(s):

Functional Diversity ◽

Functional Divergence ◽

Permanent Plots ◽

Mountain Forest ◽

Timber Species ◽

Mountain Forests ◽

Tropical Mountain ◽

Silvicultural Treatment ◽

Functional Richness ◽

The Impact

Background: The impact of selective thinning on forest diversity has been extensively studied in temperate and boreal regions. However, in the tropics, knowledge is still poor regarding the impacts of this silvicultural treatment on functional diversity, especially in tropical mountain forests, which are considered to be highly biodiverse ecosystems and also endangered by human activities. By evaluating the changes on functional diversity by using different indicators, hypothesizing that selective thinning significantly affects (directly or indirectly) tropical mountain forests, this work promotes sustainable ecosystem use. Methods: A total of 52 permanent plots of 2500 m2 each were installed in a primary mountain forest in the San Francisco Biological Reserve to assess the impact of this silvicultural treatment. Selective thinning can be defined as a controlled process, in which trees that compete with ecologically and/or valuable timber species are progressively removed to stimulate the development of profitable ones, called potential crop trees (PCT). In doing so, the best specimens remain in the forest stand until their final harvest. After PCT selection, 30 plots were chosen for the intervention, while 22 plots served as control plots. The thinning intensity fluctuated between 4 and 56 trees ha−1 (average 18.8 ± 12.1 stems ha−1). Functional Diversity (FD) indices, including the community weighted mean (CWM), were determined based on six traits using the FD package implemented in R software. The difference between initial and final conditions of functional richness (FRic), functional divergence (FDiv), functional evenness (FEve), functional dispersion (FDis), and Rao quadratic entropy (RaoQ) was modeled using linear mixed models (LMM). As fixed factors, we used all the predictors inherent to structural and ecological forest conditions before and after the selective thinning and as a random variable, we used the membership to nested sampling units. Results: Functional Richness (FRic) showed significant changes after selective thinning, the other indexes (FEve, FDis, FDiv, RaoQ) were only influenced by predictors related to ecological conditions and characteristics of the community.

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Ecological Impacts of Megaprojects: Species Succession and Functional Composition

Plants ◽

10.3390/plants10112411 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2411

Author(s):

Hamada E. Ali ◽

Solveig Franziska Bucher

Keyword(s):

Plant Species ◽

Large Scale ◽

Invasive Plant ◽

Species Traits ◽

Natural Vegetation ◽

Ecological Impacts ◽

Imperata Cylindrica ◽

Dry Matter Content ◽

Large Scale Disturbance ◽

The Impact

Land-use changes have huge impacts on natural vegetation, especially megaprojects, as the vegetation layer is destroyed in the course of construction works affecting the plant community composition and functionality. This large-scale disturbance might be a gateway for the establishment of invasive plant species, which can outcompete the natural flora. In contrast, species occurring in the area before the construction are not able to re-establish. In this study, we analyzed the impact of a pipeline construction on a wetland nature reserve located in northern Egypt. Therefore, we analyzed the plant species occurrence and abundance and measured each plant species’ traits before the construction in 2017 as well as on multiple occasions up to 2 years after the construction had finished on altogether five sampling events. We found that the construction activity led to the establishment of an invasive species which previously did not occur in the area, namely, Imperata cylindrica, whereas five species (Ipomoea carnea, Pluchea dioscoridis, Polygonum equisetiforme, Tamarix nilotica, and Typha domingensis) could not re-establish after the disturbance. The functionality of ecosystems assessed via the analysis of plant functional traits (plant height, specific leaf area, and leaf dry matter content) changed within species over all sampling events and within the community showing a tendency to approximate pre-construction values. Functional dispersion and Rao’s quadratic diversity were higher after the megaproject than before. These findings are important to capture possible re-establishment and recovery of natural vegetation after construction and raise awareness to the impact of megaprojects, especially in areas which are high priority for conservation.

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The costs of ignoring species detectability on functional diversity estimation

The Auk ◽

10.1093/auk/ukaa057 ◽

2020 ◽

Vol 137 (4) ◽

Cited By ~ 1

Author(s):

Facundo Xavier Palacio ◽

René E Maragliano ◽

Diego Montalti

Keyword(s):

Functional Diversity ◽

Functional Divergence ◽

Habitat Type ◽

Species Traits ◽

Bird Communities ◽

Imperfect Detection ◽

East Central ◽

Functional Types ◽

Functional Richness ◽

Species Occupancy

Abstract Functional diversity (FD) approaches have been increasingly used to understand ecosystem functioning in bird communities. These approaches typically rely on the assumption that species are perfectly detected in the field, despite the fact that imperfect detection represents a ubiquitous source of bias in biodiversity studies. This may be notably important in FD studies, because detection may depend on the functional traits used to compute FD metrics. However, little effort has been devoted to account for imperfect detection in FD studies, and therefore the degree to which species traits and detectability affects FD remains poorly understood. We predict that observed FD metrics may either underestimate or overestimate detection-corrected FD, because FD has multiple independent dimensions with different data properties. We assessed whether detection was related to bird traits (body mass, diet, and foraging stratum), accounting for habitat type, season, and phylogeny. We then used a multi-species occupancy model to obtain detection-corrected FD metrics (functional richness [FRic], functional evenness [FEve], and functional divergence [FDiv]), and compared observed and detection-corrected FD estimates in bird communities from east-central Argentina. Some functional types of birds (raptors and insectivores) were more easily overlooked, whereas others (seed and leaf eaters) were more easily detected. Some observed FD metrics underestimated detection-corrected FD (FRic and FDiv), whereas some others (FEve) overestimated detection-corrected FD. Both observed and detection-corrected FRic revealed differences between seasons, but not between habitat types. However, detection-corrected FEve and FDiv showed differences between seasons, contrary to observed estimates. Our results indicate that failure to account for unequal ease of detecting species can lead to erroneous estimates of FD because some functional types of birds are more easily overlooked. We outline some guidelines to help ornithologists identifying under which circumstances detection may be a concern and warn against the indiscriminate use of FD metrics without accounting for species detection.

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Global change in the functional diversity of marine fisheries exploitation over the past 65 years

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.0889 ◽

2020 ◽

Vol 287 (1933) ◽

pp. 20200889 ◽

Cited By ~ 1

Author(s):

Isaac Trindade-Santos ◽

Faye Moyes ◽

Anne E. Magurran

Keyword(s):

Functional Diversity ◽

Functional Divergence ◽

Marine Ecosystem ◽

Temporal Trends ◽

Functional Trait ◽

Marine Fisheries ◽

Large Marine Ecosystems ◽

The Past ◽

Functional Richness ◽

Spatial And Temporal Trends

Overexploitation is recognized as one of the main threats to global biodiversity. Here, we report a widespread change in the functional diversity of fisheries catches from the large marine ecosystems (LMEs) of the world over the past 65 years (1950 to 2014). The spatial and temporal trends of functional diversity exploited from the LMEs were calculated using global reconstructed marine fisheries catch data provided by the Sea Around Us initiative (including subsistence, artisanal, recreational, industrial fisheries, and discards) and functional trait data available in FishBase. Our analyses uncovered a substantial increase in the functional richness of both ray-finned fishes (80% of LMEs) and cartilaginous species (sharks and rays) (75% of LMESs), in line with an increase in the taxonomic richness, extracted from these ecosystems. The functional evenness and functional divergence of these catches have also altered substantially over the time span of this study, with considerable geographic variation in the patterns detected. These trends show that global fisheries are increasingly targeting species that play diverse roles within the marine ecosystem and underline the importance of incorporating functional diversity in ecosystem management.

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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.

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Functional richness, functional evenness and functional divergence: the primary components of functional diversity

Oikos ◽

10.1111/j.0030-1299.2005.13886.x ◽

2005 ◽

Vol 111 (1) ◽

pp. 112-118 ◽

Cited By ~ 823

Author(s):

Norman W. H. Mason ◽

David Mouillot ◽

William G. Lee ◽

J. Bastow Wilson

Keyword(s):

Functional Diversity ◽

Functional Divergence ◽

Functional Richness ◽

Functional Evenness

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Functional Traits of Plant Species Suitable for Revegetation of Landfill Waste from Nickel Smelter

Applied Sciences ◽

10.3390/app11020658 ◽

2021 ◽

Vol 11 (2) ◽

pp. 658

Author(s):

Malvína Čierniková ◽

Ivana Vykouková ◽

Tomáš Orfánus ◽

Elena Masarovičová

Keyword(s):

Plant Species ◽

Functional Traits ◽

Water Saturation ◽

Matter Content ◽

Leaf Water Content ◽

Dry Matter Content ◽

Populus Alba ◽

Water Saturation Deficit ◽

Nickel Smelter ◽

Calamagrostis Epigejos

The landfill waste of leached ore residue represents a serious environmental risk and may also negatively affect the appearance, growth and development of vegetation. Here we focused on the evaluation of functional traits of selected plant species Populus alba, Calamagrostis epigejos, and Diplotaxis muralis growing in an unfavourable environment. We determined different adaptive strategies of selected species to extreme conditions. For Diplotaxis muralis the highest values of the leaf dry matter content (LDMC) and the lowest values of the specific leaf area (SLA) were determined, while for Calamagrostis epigejos these two traits correlated in opposite directions. Populus alba reached the lowest value of the water saturation deficit (WSD), suggesting that this species was most affected by soil water deficiency. The leaf water content (LWC) correlated negatively with the LDMC and positively with the SLA (narrow leaf blade). Although each plant species belongs to a different strategic group (therophyte, hemicryptophyte and phanerophyte in the juvenile stage), they are all very plastic and therefore suitable for remediation. Despite the unfavourable conditions, selected plant species were able to adapt to poor conditions and form more or less vital populations, which indicate the revegetation as a key measure for remediation of landfill waste from nickel smelter.

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Functional Traits on Cavity-nesting Birds in Subtropical Andean Forest: Response to Logging Activity and Comparing with American Temperate Forests

10.21203/rs.3.rs-555302/v1 ◽

2021 ◽

Author(s):

Alejandro A. Schaaf ◽

Daniela Gomez ◽

Ever Tallei ◽

Constanza G. Vivanco ◽

Román A. Ruggera

Keyword(s):

Functional Traits ◽

Temperate Forests ◽

Functional Divergence ◽

Functional Changes ◽

Point Counts ◽

Cavity Nesting ◽

Functional Richness ◽

Bird Richness ◽

Community Weighted Mean ◽

Species Richness And Abundance

Abstract Logging causes changes in habitat structure, which can potentially lead to variations in taxonomic and functional richness of biodiversity. In this paper, we examined how logging in subtropical Andean forests has influenced taxonomic and functional diversity of cavity-nesting birds. We used point-counts to examine the effects of logging on taxonomic and functional traits of avian communities (Functional Richness, Functional evenness, Functional Divergence, and Community-weighted mean). We found that logging changes bird richness and abundance, although it had no effect on the functional response to the measured traits. The comparison of our results with those of temperate forests of Canada and Chile reveals differences in the functional richness, with a lower impact of logging on functional traits. We highlight the importance of including functional traits in the analyses, since the reduction in the species richness and abundance may not translate into functional changes within the ecosystem.

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