Something is not quite right: Effects of two land uses on anuran diversity in subtropical grasslands

Abstract

Although habitat modification is considered one of the main causes of biodiversity loss, the relative contribution of different rural land uses to biodiversity conservation is far less known. Additionally, the realization of the multidimensionality of biodiversity demands studies integrating variation of functional traits and phylogenetic information as complements to address the effects of land use on the structure of animal communities. Herein, we investigated the effects of land use (i.e., intensive agricultural and extensive livestock rearing) on functional and phylogenetic diversity of anuran communities in farmland ponds from the Uruguayan savanna ecoregion, while considering the effects of local factors (i.e., water depth) on species composition. We surveyed adults and tadpoles in 22 ponds and quantified five traits related to tadpole feeding, habitat use, and predator avoidance. Tadpole identification was corroborated by DNA barcoding based on a fragment of the mitochondrial 16S rRNA gene. We observed a decline in phylogenetic mean nearest taxon distance associated with increase of surrounding agricultural land use. While land use intensification did not affect richness (functional or phylogenetic), ponds in livestock ranches hosted about four times more tadpoles than agricultural ponds. Functional evenness decreased with water depth, although such relationship disappeared when considering phylogenetic non-independence. Our results indicated that specific anuran clades were more sensitive to intensification in land use, reinforcing a recent view of phylogenetic homogenization following habitat conversion. Additionally, our study suggests that extensive cattle grazing over wide native pastures may provide an alternative more compatible with conservation than short-term crops in subtropical grasslands.

Functional traits drive tadpole responses to land use in coastal areas

“…Ignoring such phylogenetic relationships might distort inferences of assembly mechanisms because of biological and methodological reasons (Cadotte et al, 2017). For example, functional evenness (FEve) decreases with water depth, but such association seems to be a statistical artefact generated by phylogenetic non-independency among tadpole species (Moreira et al, 2020). As such, combining functional and phylogenetic metrics enables insights into evolutionary and ecological dynamics (Lipinski et al, 2020;Ribeiro et al, 2017).…”

Exploring patterns of taxonomic, functional and phylogenetic β-diversity variation of Neotropical small mammals in a highly fragmented landscape

“…In a community dynamic viewpoint, β-diversity increases (greater heterogenization) when common species do not co-occur among all sites, or when new species arrive at some sites; and β-diversity decreases (homogenization) when rare or non-common species become extinct, or when formerly rare or absent species become widespread (Socolar et al 2016). Variation in the trajectory of β-diversity can be caused by different effects of human disturbance (Tscharntke et Functional and phylogenetic β-diversity have been relatively less investigated in fragmented landscapes when compared to traditional taxonomic metrics (Moreno et al 2018), but despite being less used, some studies show that a decrease in such dimensions of β-diversity are associated with land-use intensi cation (Pereira et al 2018;Moreira et al 2020). Thus, decomposition of biodiversity into different dimensions may allow greater understanding of how communities are affected by forest conversion and fragmentation (Cisneros et al 2015).…”

Influence of vegetation regeneration and agricultural land use on lizard composition, taxonomic and functional diversity between different vegetation types in Caatinga domain, Brazil

“…The conversion of pristine habitats into agricultural areas is one of the main ways of intensifying land use worldwide (Ellis et al, 2010). This often negatively impacts biodiversity (Moreira et al, 2020; Susi & Laine, 2021) through changes in conditions, resources, and interactions between organisms (Valladares et al, 2015). After use and consecutive land abandonment, it is expected that the regeneration of native vegetation will gradually recover the diversity and functioning of the environment, depending on factors such as previous land use and the type of native vegetation (Latawiec et al, 2016; Warring et al, 2016).…”

“…We evaluate how changes in stage of native vegetation regeneration and agricultural land use affects lizard assemblages composition, functional and taxonomic diversity considering different vegetation types in Caatinga domain (Caatinga sensu stricto, Cerrado sensu stricto and Relictual Humid Forest). We used diversity metrics widely explored in diversity studies in different groups of organisms (e.g., fish – Villéger et al, 2010; plants – Sitters et al, 2016; lizards – Berriozabal‐Islas et al, 2017; birds – Matuoka et al, 2020; amphibians – Moreira et al, 2020). To represent taxonomic diversity, we used species richness (number of species), species evenness (species abundance distribution, Pielou, 1966) and abundance (total number of individuals in the investigated taxon – lizards).…”