Landscape Structure Is a Major Driver of Bee Functional Diversity in Crops

Land-use change is having a negative effect on pollinator communities, and these changes in community structure may have unexpected impacts on the functional composition of those communities. Such changes in functional composition may impact the capacity of these assemblages to deliver pollination services, affecting the reproduction of native and wild plants. However, elucidating those relationships requires studies in multiple spatial scales because effects and consequences are different considering biological groups and interactions. In that sense, by using a multi-trait approach, we evaluated whether the landscape structure and/or local environmental characteristics could explain the functional richness, divergence, and dispersion of bee communities in agroecosystems. In addition, we investigated to what extent this approach helps to predict effects on pollination services. This study was conducted in an agroecosystem situated in the Chapada Diamantina region, State of Bahia, Brazil. Bees were collected using two complementary techniques in 27 sample units. They were classified according to their response traits (e.g., body size, nesting location) and effect traits (e.g., means of pollen transportation, specialty in obtaining resources). The Akaike information criterion was used to select the best models created through the additive combination of landscape descriptors (landscape diversity, mean patch shape, and local vegetation structure) at the local, proximal, and broad landscape levels. Our results indicate that both landscape heterogeneity and configuration matter in explaining the three properties of bee functional diversity. We indicate that functional diversity is positively correlated with compositional and configurational heterogeneity. These results suggest that landscape and local scale management to promote functional diversity in pollinator communities may be an effective mechanism for supporting increased pollination services.

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Landscape Heterogeneity and Dynamics

Essentials of Landscape Ecology ◽

10.1093/oso/9780198838388.003.0003 ◽

2019 ◽

pp. 42-126

Author(s):

Kimberly A. With

Keyword(s):

Landscape Ecology ◽

Spatial Heterogeneity ◽

Landscape Structure ◽

Landscape Heterogeneity ◽

Spatial Scales ◽

Anthropogenic Disturbances ◽

Ecological Processes ◽

Disturbance Dynamics ◽

Wide Range ◽

Over Time

Heterogeneity is a defining characteristic of landscapes and therefore central to the study of landscape ecology. Landscape ecology investigates what factors give rise to heterogeneity, how that heterogeneity is maintained or altered by natural and anthropogenic disturbances, and how heterogeneity ultimately influences ecological processes and flows across the landscape. Because heterogeneity is expressed across a wide range of spatial scales, the landscape perspective can be applied to address these sorts of questions at any level of ecological organization, and in aquatic and marine systems as well as terrestrial ones. Disturbances—both natural and anthropogenic—are a ubiquitous feature of any landscape, contributing to its structure and dynamics. Although the focus in landscape ecology is typically on spatial heterogeneity, disturbance dynamics produce changes in landscape structure over time as well as in space. Heterogeneity and disturbance dynamics are thus inextricably linked and are therefore covered together in this chapter.

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Influence of landscape structure on Euglossini composition in open vegetation environments

Biota Neotropica ◽

10.1590/1676-0611-bn-2016-0294 ◽

2017 ◽

Vol 17 (1) ◽

Cited By ~ 6

Author(s):

Eduardo Freitas Moreira ◽

Rafaela Lorena da Silva Santos ◽

Maxwell Souza Silveira ◽

Danilo Boscolo ◽

Edinaldo Luz das Neves ◽

...

Keyword(s):

Species Richness ◽

Landscape Structure ◽

Multiple Scales ◽

Landscape Heterogeneity ◽

Species Abundance ◽

Information Criterion ◽

Landscape Configuration ◽

Habitat Amount ◽

Savanna Vegetation ◽

Habitat Amount Hypothesis

Abstract The fauna of Euglossini bees is poorly known in savanna regions, making it difficult to understand how these bees use open vegetation environments. The aim of this study was to evaluate the influence of landscape structure on species abundance and composition of Euglossini bees in naturally heterogeneous savanna landscapes. Nine sites were sampled monthly using six traps with chemical baits. Three aromatic essences (eucalyptol, methyl salicylate and vanillin) were used to attract the Euglossini. Surrounding environmental conditions were measured using three independent variables, calculated in multiple scales: index of local vegetation and two landscape indices (Shannon Diversity and area-weighted shape). We compared the competing hypotheses through model selection based on Second-order Akaike Information Criterion (AICc). The four competing hypothesis were: (1) The local vegetation complexity favors Euglossini bees species richness and/or abundance (local vegetation hypothesis); (2) The proportion of the native vegetation types favors Euglossini bees species richness and/or abundance (habitat amount hypothesis); (3) Higher landscape diversity shall increase species richness of Euglossini bees (landscape heterogeneity hypothesis); (4) More complex landscape configuration shall favor the Euglossini bees richness and/or abundance (landscape heterogeneity hypothesis). We sampled 647 individuals belonging to six species of two distinct genera. Our results support the habitat amount hypothesis since bees’ abundance was strongly related with the proportion of habitat in the surrounding landscape. This may be related to the availability of floral and nesting resources in some types of savanna vegetation.

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Qualitative and Quantitative Loss of Habitat at Different Spatial Scales Affects Functional Moth Diversity

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.637371 ◽

2021 ◽

Vol 9 ◽

Author(s):

Britta Uhl ◽

Mirko Wölfling ◽

Konrad Fiedler

Keyword(s):

Functional Diversity ◽

Habitat Quality ◽

Spatial Scales ◽

Landscape Scale ◽

Nature Reserves ◽

Insect Diversity ◽

Ecosystem Resilience ◽

Scale Factors ◽

Functional Richness ◽

Local Habitat

Land use change has led to large-scale insect decline, threatening ecosystem resilience through reduced functional diversity. Even in nature reserves, losses in insect diversity have been detected. Hereby, changes in local habitat quality and landscape-scale habitat quantity can play a role driving functional diversity toward erosion. Our aim was to analyze how local and landscape-scale factors simultaneously affect functional insect diversity. Therefore, we sampled moths in two Italian coastal forest reserves at 60 sites. Our focus was on functional richness, redundancy and niche occupation, being important for ecosystem resilience, following the insurance framework. Ecological information about 387 species and 14 traits was used to analyze functional diversity. Twenty-five functional groups were recognized and used to estimate niche occupation and redundancy. Fourteen local and 12 landscape-scale factors were measured and condensed by using Principal Components Analysis. The resulting PC-axes served as predictors in linear mixed effects models. Functional richness, redundancy and niche occupation of moths were lower at sites with low habitat quality and quantity, indicating reduced ecosystem resilience. Especially landscape diversity and habitat structure, viz. a humidity-nutrient gradient, but also plant diversity, were promoting functional richness. Landscape fragmentation, indicating increased impermeability for insects, reduced local functional richness, redundancy and niche occupation. Local habitat quality and landscape-wide habitat quantity are both important for maintaining functional insect diversity inside reserves. Therefore, small and isolated nature reserves might fail in preserving biodiversity and ecosystem functions through adverse effects acting from the surrounding landscape structure and configuration.

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Does landscape context affect pollination-related functional diversity and richness of understory flowers in forest fragments of Atlantic Rainforest in southeastern Brazil?

Ecological Processes ◽

10.1186/s13717-020-00261-6 ◽

2020 ◽

Vol 9 (1) ◽

Author(s):

Karoline Baptista de Lima ◽

Patrícia Alves Ferreira ◽

Milton Groppo ◽

Renato Goldenberg ◽

Emerson Ricardo Pansarin ◽

...

Keyword(s):

Functional Diversity ◽

Plant Communities ◽

Forest Cover ◽

Linear Models ◽

Landscape Heterogeneity ◽

Regional Scale ◽

Information Criterion ◽

Flowering Plant ◽

Southeastern Brazil ◽

Forest Fragments

Abstract Background How landscape modifications affect functional diversity of floral characteristics pertinent to pollinators is poorly known. Flowers possess functional traits that sometimes coevolved with pollinators, crucial for the maintenance of both pollinator and plant communities. We evaluated how richness and functional diversity of available understory flowers respond to forest cover and landscape heterogeneity in a multiscale analysis. Plants in bloom were sampled from 25 landscapes in the understory of Atlantic Forest fragments in Brazil. Species were classified into functional groups regarding flower characteristics relevant to pollination. Landscape heterogeneity and forest cover were measured in buffers ranging from 200 to 2000 m from sampling units and their correlation with plant richness and functional diversity was assessed using generalized linear models and further model selection through Akaike’s second-order information criterion. Results Plants’ richness and functional diversity were affected negatively by forest cover. The former responded to forest cover at a regional scale while the latter responded at a local scale. Higher landscape heterogeneity increased richness and functional diversity. Conclusions Our results showed that forest cover and landscape heterogeneity are important to support biodiversity related to pollination, mostly due to the availability of diversified resources and nesting sites associated to different land-uses for pollinators and flowering plant communities. These findings should highlight, along with forest cover, landscape heterogeneity as an environmental management priority in rural tropical areas for mitigating the loss of plant biodiversity and enhancing ecosystem functioning.

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The Effect of Climate and Human Pressures on Functional Diversity and Species Richness Patterns of Amphibians, Reptiles and Mammals in Europe

Diversity ◽

10.3390/d13060275 ◽

2021 ◽

Vol 13 (6) ◽

pp. 275

Author(s):

Mariana A. Tsianou ◽

Maria Lazarina ◽

Danai-Eleni Michailidou ◽

Aristi Andrikou-Charitidou ◽

Stefanos P. Sgardelis ◽

...

Keyword(s):

Species Richness ◽

Functional Diversity ◽

Agricultural Land ◽

Influential Factor ◽

Climatic Variables ◽

Quadratic Entropy ◽

Functional Richness ◽

Precipitation Seasonality ◽

Rao’S Quadratic Entropy ◽

Richness Patterns

The ongoing biodiversity crisis reinforces the urgent need to unravel diversity patterns and the underlying processes shaping them. Although taxonomic diversity has been extensively studied and is considered the common currency, simultaneously conserving other facets of diversity (e.g., functional diversity) is critical to ensure ecosystem functioning and the provision of ecosystem services. Here, we explored the effect of key climatic factors (temperature, precipitation, temperature seasonality, and precipitation seasonality) and factors reflecting human pressures (agricultural land, urban land, land-cover diversity, and human population density) on the functional diversity (functional richness and Rao’s quadratic entropy) and species richness of amphibians (68 species), reptiles (107 species), and mammals (176 species) in Europe. We explored the relationship between different predictors and diversity metrics using generalized additive mixed model analysis, to capture non-linear relationships and to account for spatial autocorrelation. We found that at this broad continental spatial scale, climatic variables exerted a significant effect on the functional diversity and species richness of all taxa. On the other hand, variables reflecting human pressures contributed significantly in the models even though their explanatory power was lower compared to climatic variables. In most cases, functional richness and Rao’s quadratic entropy responded similarly to climate and human pressures. In conclusion, climate is the most influential factor in shaping both the functional diversity and species richness patterns of amphibians, reptiles, and mammals in Europe. However, incorporating factors reflecting human pressures complementary to climate could be conducive to us understanding the drivers of functional diversity and richness patterns.

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Dispersal and Land Cover Contribute to Pseudorabies Virus Exposure in Invasive Wild Pigs

EcoHealth ◽

10.1007/s10393-020-01508-6 ◽

2021 ◽

Author(s):

Felipe A. Hernández ◽

Amanda N. Carr ◽

Michael P. Milleson ◽

Hunter R. Merrill ◽

Michael L. Avery ◽

...

Keyword(s):

Land Cover ◽

Disease Transmission ◽

Wildlife Conservation ◽

Pseudorabies Virus ◽

Spatial Scales ◽

Information Criterion ◽

Small Scale ◽

Wild Pigs ◽

Bacterial Agent ◽

Open Canopy

AbstractWe investigated the landscape epidemiology of a globally distributed mammal, the wild pig (Sus scrofa), in Florida (U.S.), where it is considered an invasive species and reservoir to pathogens that impact the health of people, domestic animals, and wildlife. Specifically, we tested the hypothesis that two commonly cited factors in disease transmission, connectivity among populations and abundant resources, would increase the likelihood of exposure to both pseudorabies virus (PrV) and Brucella spp. (bacterial agent of brucellosis) in wild pigs across the Kissimmee Valley of Florida. Using DNA from 348 wild pigs and sera from 320 individuals at 24 sites, we employed population genetic techniques to infer individual dispersal, and an Akaike information criterion framework to compare candidate logistic regression models that incorporated both dispersal and land cover composition. Our findings suggested that recent dispersal conferred higher odds of exposure to PrV, but not Brucella spp., among wild pigs throughout the Kissimmee Valley region. Odds of exposure also increased in association with agriculture and open canopy pine, prairie, and scrub habitats, likely because of highly localized resources within those land cover types. Because the effect of open canopy on PrV exposure reversed when agricultural cover was available, we suggest that small-scale resource distribution may be more important than overall resource abundance. Our results underscore the importance of studying and managing disease dynamics through multiple processes and spatial scales, particularly for non-native pathogens that threaten wildlife conservation, economy, and public health.

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Repeated surveying over 6 years reveals that fine-scale habitat variables are key to tropical mountain ant assemblage composition and functional diversity

Scientific Reports ◽

10.1038/s41598-020-80077-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mulalo M. Muluvhahothe ◽

Grant S. Joseph ◽

Colleen L. Seymour ◽

Thinandavha C. Munyai ◽

Stefan H. Foord

Keyword(s):

Climate Change ◽

Species Composition ◽

High Altitude ◽

Functional Diversity ◽

Large Scale ◽

Climate Models ◽

Spatial Scales ◽

Abiotic Factors ◽

Composition Analysis ◽

Fine Scale

AbstractHigh-altitude-adapted ectotherms can escape competition from dominant species by tolerating low temperatures at cooler elevations, but climate change is eroding such advantages. Studies evaluating broad-scale impacts of global change for high-altitude organisms often overlook the mitigating role of biotic factors. Yet, at fine spatial-scales, vegetation-associated microclimates provide refuges from climatic extremes. Using one of the largest standardised data sets collected to date, we tested how ant species composition and functional diversity (i.e., the range and value of species traits found within assemblages) respond to large-scale abiotic factors (altitude, aspect), and fine-scale factors (vegetation, soil structure) along an elevational gradient in tropical Africa. Altitude emerged as the principal factor explaining species composition. Analysis of nestedness and turnover components of beta diversity indicated that ant assemblages are specific to each elevation, so species are not filtered out but replaced with new species as elevation increases. Similarity of assemblages over time (assessed using beta decay) did not change significantly at low and mid elevations but declined at the highest elevations. Assemblages also differed between northern and southern mountain aspects, although at highest elevations, composition was restricted to a set of species found on both aspects. Functional diversity was not explained by large scale variables like elevation, but by factors associated with elevation that operate at fine scales (i.e., temperature and habitat structure). Our findings highlight the significance of fine-scale variables in predicting organisms’ responses to changing temperature, offering management possibilities that might dilute climate change impacts, and caution when predicting assemblage responses using climate models, alone.

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Remotely Sensed Single Tree Data Enable the Determination of Habitat Thresholds for the Three-Toed Woodpecker (Picoides tridactylus)

Remote Sensing ◽

10.3390/rs10121972 ◽

2018 ◽

Vol 10 (12) ◽

pp. 1972 ◽

Cited By ~ 10

Author(s):

Katarzyna Zielewska-Büttner ◽

Marco Heurich ◽

Jörg Müller ◽

Veronika Braunisch

Keyword(s):

Bark Beetles ◽

Laser Scanning ◽

Positive Relationship ◽

Spatial Scales ◽

Keystone Species ◽

Remote Sensing Data ◽

Individual Tree ◽

Substrate Quality ◽

Dead Trees ◽

Negative Effect

Forest biodiversity conservation requires precise, area-wide information on the abundance and distribution of key habitat structures at multiple spatial scales. We combined airborne laser scanning (ALS) data with color-infrared (CIR) aerial imagery for identifying individual tree characteristics and quantifying multi-scale habitat requirements using the example of the three-toed woodpecker (Picoides tridactylus) (TTW) in the Bavarian Forest National Park (Germany). This bird, a keystone species of boreal and mountainous forests, is highly reliant on bark beetles dwelling in dead or dying trees. While previous studies showed a positive relationship between the TTW presence and the amount of deadwood as a limiting resource, we hypothesized a unimodal response with a negative effect of very high deadwood amounts and tested for effects of substrate quality. Based on 104 woodpecker presence or absence locations, habitat selection was modelled at four spatial scales reflecting different woodpecker home range sizes. The abundance of standing dead trees was the most important predictor, with an increase in the probability of TTW occurrence up to a threshold of 44–50 dead trees per hectare, followed by a decrease in the probability of occurrence. A positive relationship with the deadwood crown size indicated the importance of fresh deadwood. Remote sensing data allowed both an area-wide prediction of species occurrence and the derivation of ecological threshold values for deadwood quality and quantity for more informed conservation management.

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Context-dependency in biodiversity-multifunctionality relationships is driven by nitrogen availability and plant functional composition

10.1101/2020.08.17.254086 ◽

2020 ◽

Author(s):

Noémie A. Pichon ◽

Seraina L. Cappelli ◽

Santiago Soliveres ◽

Tosca Mannall ◽

Thu Zar Nwe ◽

...

Keyword(s):

Species Richness ◽

Plant Species ◽

Functional Diversity ◽

Experimental Studies ◽

Plant Species Richness ◽

Trophic Levels ◽

Context Dependency ◽

Composition Gradient ◽

Nitrogen Enrichment ◽

Functional Composition

SummaryThe ability of an ecosystem to deliver multiple functions at high levels (multifunctionality) typically increases with biodiversity but there is substantial variation in the strength and direction of biodiversity effects, suggesting context-dependency. However, the drivers of this context dependency have not been identified and understood in comparative meta-analyses or experimental studies. To determine how different factors modulate the effect of diversity on multifunctionality, we conducted a large grassland experiment with 216 communities, crossing a manipulation of plant species richness (1-20 species) with manipulations of resource availability (nitrogen enrichment), plant functional composition (gradient in mean specific leaf area [SLA] to manipulate abundances of fast vs. slow species), plant functional diversity (variance in SLA) and enemy abundance (fungal pathogen removal). We measured ten functions, above and belowground, related to productivity, nutrient cycling and energy transfer between trophic levels, and calculated multifunctionality. Plant species richness and functional diversity both increased multifunctionality, but their effects were context dependent. Species richness increased multifunctionality, but only when communities were assembled with fast growing (high SLA) species. This was because slow species were more redundant in their functional effects, whereas fast species tended to promote different functions. Functional diversity also increased multifunctionality but this effect was dampened by nitrogen enrichment, however, unfertilised, functionally diverse communities still delivered more functions than low diversity, fertilised communities. Our study suggests that a shift towards exploitative communities will not only alter ecosystem functioning but also the strength of biodiversity-functioning relationships, which highlights the potentially complex effects of global change on multifunctionality.

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Impact of urbanization on functional diversity in macromycete communities along an urban ecosystem in Southwest Mexico

PeerJ ◽

10.7717/peerj.12191 ◽

2021 ◽

Vol 9 ◽

pp. e12191

Author(s):

Marko Gómez-Hernández ◽

Emily Avendaño-Villegas ◽

María Toledo-Garibaldi ◽

Etelvina Gándara

Keyword(s):

Species Richness ◽

Functional Diversity ◽

Ecosystem Functioning ◽

Urban Ecosystem ◽

Niche Space ◽

Urbanization Gradient ◽

Urbanization Level ◽

Functional Value ◽

Functional Richness ◽

Available Resources

Macromycetes are a group of fungi characterized by the production of fruit bodies and are highly relevant in most terrestrial ecosystems as pathogens, mutualists, and organic matter decomposers. Habitat transformation can drastically alter macromycete communities and diminish the contribution of these organisms to ecosystem functioning; however, knowledge on the effect of urbanization on macrofungal communities is scarce. Diversity metrics based on functional traits of macromycete species have shown to be valuable tools to predict how species contribute to ecosystem functionality since traits determine the performance of species in ecosystems. The aim of this study was to assess patterns of species richness, functional diversity, and composition of macrofungi in an urban ecosystem in Southwest Mexico, and to identify microclimatic, environmental, and urban factors related to these patterns in order to infer the effect of urbanization on macromycete communities. We selected four oak forests along an urbanization gradient and established a permanent sampling area of 0.1 ha at each site. Macromycete sampling was carried out every week from June to October 2017. The indices used to measure functional diversity were functional richness (FRic), functional divergence (FDig), and functional evenness (FEve). The metric used to assess variation of macrofungal ecological function along the study area was the functional value. We recorded a total of 134 macromycete species and 223 individuals. Our results indicated a decline of species richness with increased urbanization level related mainly to microclimatic variables, and a high turnover of species composition among study sites, which appears to be related to microclimatic and urbanization variables. FRic decreased with urbanization level, indicating that some of the available resources in the niche space within the most urbanized sites are not being utilized. FDig increased with urbanization, which suggests a high degree of niche differentiation among macromycete species within communities in urbanized areas. FEve did not show notable differences along the urbanization gradient, indicating few variations in the distribution of abundances within the occupied sections of the niche space. Similarly, the functional value was markedly higher in the less urbanized site, suggesting greater performance of functional guilds in that area. Our findings suggest that urbanization has led to a loss of macromycete species and a decrease in functional diversity, causing some sections of the niche space to be hardly occupied and available resources to be under-utilized, which could, to a certain extent, affect ecosystem functioning and stability.

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