10.5061/DRYAD.TDZ08KPX4
Moreira, Leonardo Felipe Bairos
0000-0002-2753-9933
Universidade Federal de Mato Grosso
Castilhos, Henrique Zanette de
Pontifical Catholic University of Rio Grande do Sul
Castroviejo-Fisher, Santiago
Pontifical Catholic University of Rio Grande do Sul
Something is not quite right: effects of two land uses on anuran diversity
in subtropical grasslands
Dryad
dataset
2020
community phylogenetic
Pampa
tadpoles.
Coordenação de Aperfeicoamento de Pessoal de Nível Superior
https://ror.org/00x0ma614
20132816
National Council for Scientific and Technological Development
https://ror.org/03swz6y49
442987/20
2020-08-14T00:00:00Z
2020-08-14T00:00:00Z
en
38651 bytes
2
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Although habitat modification is considered one of the main causes of
biodiversity loss, the relative contribution of different rural land uses
to biodiversity conservation are 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.
In the spring of 2015 (10–16 October), we sampled tadpoles in 22 ponds
located 5.5–316 km apart in southern Brazil. In order to ensure that the
landscape composition surrounding each pond did not change over different
scales, we defined circular areas (1,000 m radius) and measured land-cover
data , using Qgis 2.18.16 . We based analysis on Google Earth imagery,
using a land-cover classification for 2015 produced within the scope of
the MapBiomas initiative. At each pond, we performed eight dip-net sweeps
(30 cm diameter, 2mm mesh), each covering approximately 1 m2 and
distributed at different pond depths (i.e., four sweeps near the edge of
the pond and four sweeps in deep water near the centre of the pond).
Sweeps were pooled into one sample per pond (3.5 L plastic bucket), where
the collected tadpoles were euthanized with a benzocaine solution and
sorted into series based on their morphology (i.e. coloration, body shape,
eyes position, tail fin proportion, and mouth position). We also
registered the presence of all observed adults, visually or acoustically,
during tadpole sampling. In laboratory, each tadpole without tail clip was
rinsed in distilled water and then measured for a set of eight
morphological traits on an automated stereomicroscope – Leica M205A.
See attached Read_me.txt for additional information.