DOI: 10.5061/dryad.9s4mw6mqz
title: Data from: From leaves to whole plants: effects of shelter-builders on arthropod communities are stronger in dry seasons

description: Leaf shelters function as microclimatic refuges, reducing arthropod
 exposure to climatic fluctuations of surrounding habitats. Although
 facilitation is expected to increase under stressful conditions, empirical
 studies investigating the patterns of variation and magnitude of effects
 of ecosystem engineering at different spatial and temporal scales are
 still scarce. In this study we evaluated the facilitation consequences of
 leaf shelter created by gall-inducers on arthropod communities of Miconia
 ligustroides (DC.) Naudin (Melastomataceae). We evaluated how such effects
 change at the leaf and plant levels in an environment subject to strong
 climatic seasonality. The presence of leaf shelters on M. ligustroides
 increased arthropod diversity and biomass, modified the species
 composition at both the leaf and plant levels, and in wet and dry seasons.
 However, the addition of artificial leaf shelters during the dry season
 showed greater abundance, richness, and biomass of arthropods when
 compared to shelters added during the wet season. Regarding the global
 effects of artificial leaf shelters on the diversity of arthropods
 associated with M. ligustroides, the dry season showed strong and positive
 effects, increasing the abundance, richness, and biomass of arthropods by
 an average of 65% for both years. Our study contributes to a better
 understanding of the patterns of variation and magnitude of ecosystem
 engineering at different spatial and temporal scales and provides new
 insights into the importance of shelters for aridity-sensitive species.
description: <strong>The raw data available here were used to run the
 data proposed in the following methodology. For more details, see the
 published article, as well as Table 1 and Supporting Information
 S1.</strong> Data sampling
 <em>Leaf scale</em> To evaluate
 the effects of leaf shelters on arthropod secondary colonization, 30
 plants spaced approximately 10.0 m from each other were marked in the
 field in February 2020. All plants were between 1.0 and 1.5 m tall and had
 no flowers and fruits at the beginning of the study. In each plant, two
 pairs of leaves were selected as treatments (n = 4, artificial leaf
 rolls), and two pairs of leaves as control (n = 4, expanded leaves). We
 used different branches for each pair and marked the branches with colored
 tags (Figure 3). The treatment pairs consisted of a
 rolled leaf simulating a shelter created by <em>D.
 gallaeformans</em> (Figure 2d). We use young, intact, and fully
 developed leaves to create these artificial shelters. We opted to use
 intact leaves to create the shelters because the galled leaves are
 extremely fragile and break easily when manipulated. Furthermore, a
 previous study showed that the use of these artificial shelters resembles
 natural shelters, as they exhibited 79% of species similarity of secondary
 occupants with natural shelters (Pereira et al., 2021).
 Leaves were manually rolled from the abaxial to the adaxial face,
 from the edges to the midrib, and secured with hairpins, which were
 painted the same color as the leaves with odorless green spray paint
 (Figure 2d). These artificial shelters simulate cylindrical rolls, 20 mm
 in diameter, similar to leaf roll galls naturally created on these plants
 by the nematode. In previous experiments (Pereira et al., 2021), we showed
 that 10 days were sufficient for the colonization of these shelters. Thus,
 after 15 days of setting up the experiment, artificial rolls and expanded
 leaves were collected, stored in plastic bags with zipper closure, and
 frozen for later sorting. After this collection, we set up the experiment
 again and carried out a second collection after 15 days. The treatments
 were reapplied to the same trees and branches using different pairs of
 leaves. To evaluate the effects of shelters over
 seasons, this experiment was repeated on the same individuals in August
 2020 (dry season), as well as in the wet (February) and dry (August)
 seasons of 2021. <em>Plant
 scale</em> To assess whether leaf roll galls
 increase arthropod diversity in <em>M. ligustroides</em>, 60
 plants at least 10.0 m apart were tagged in January 2020 (wet season) and
 two groups were selected: i) plants with leaf roll galls (n = 30, control)
 and ii) plants with galls removed (n = 30, treatment). All plants were
 between 1.0 and 1.5 m tall and had no flowers and fruits at the time of
 the study. Individuals of <em>M. ligustroides</em> had an
 average of ten leaves curled from galls of similar age, and for the plants
 in the treatment group, we removed all leaves that had galls (as there
 were no plants naturally without galls). This represents approximately
 only 1% of biomass removal, as plants on the treatment group had an
 average of 1,021 (± 106.99 SE) leaves (see Pereira et al. 2021). One month
 after marking the groups of plants (February 2020) and removing the galls
 from the treatment group, the entire plants were visually inspected for 25
 minutes and the arthropods were collected using entomological forceps and
 aspirators. Collections were carried out between 10 am and 2 pm, the
 period when we observed the highest arthropod activity in the studied
 area. We used zippered plastic bags to collect the shelters and froze them
 for arthropod screening. To assess the effects of shelters over seasons,
 this experiment was repeated on the same individuals in July 2020 (dry
 season), as well as in the wet and dry seasons of the following year
 (January and July 2021, respectively).
 <em>Arthropod screening and
 identification</em> We inspected the collected
 leaves and shelters using a stereomicroscope. All arthropods found were
 stored in 70% alcohol and identified to the lowest possible taxonomic
 level or classified into morphospecies (Oliver & Beattie, 1996) to
 allow the assessment of abundance, richness and dry biomass (in mg).
 Furthermore, we classified arthropods into feeding guilds as detritivores,
 herbivores, omnivores, parasites, parasitoids, and predators. All
 arthropods were dried in an oven at 60°C for 24 hours and weighed on a
 precision digital scale to estimate biomass (in mg).
 Data analysis We used generalized linear mixed
 models (GLMMs) to evaluate the effects of shelters on arthropod diversity
 and biomass at the leaf level (Experiment 1). For this, we used the
 average values of abundance, richness, and biomass as response variables,
 each treatment as a fixed factor and individual plants as a random
 factor. At the plant level (Experiment 2), the effects
 of shelters on arthropod diversity and biomass were also assessed by
 GLMMs. We used the average values of abundance, richness, and biomass as
 dependent variables, each treatment as a fixed factor and individual
 plants as random factors. The distribution of errors in the aforementioned
 analyzes was verified using restricted maximum likelihood
 (REML). We used analysis of similarities (ANOSIMs)
 based on Euclidean distances to evaluate arthropod composition at the leaf
 and plant levels between different treatments. One-sided significance was
 calculated by permuting the groups with 9,999 permutations. ANOSIMs paired
 between all pairs of groups were used as a post-hoc test. To view
 similarities or differences between treatments, we used non-metric
 multidimensional scaling (NMDS) analyses, using species abundance for each
 individual plant sampled. All analyzes mentioned above were performed
 using the Vegan package (Oksanen et al., 2013) in the R software (R Core
 Team, 2022). We used Hedges'd metric to estimate
 the magnitude of the effects of adding leaf shelters on arthropod
 abundance, richness and biomass in the dry and rainy seasons of 2020 and
 2021 (Hedges & Vevea, 1998). For replicates among treatments, the
 mean and standard deviation from the 4 leaves per plant, per treatment,
 were used. Overall effect sizes were calculated on the response variables
 of arthropod abundance, richness and biomass. Groups were assigned to
 expanded leaves (control) and leaf rolls (treatment). To estimate the
 cumulative effect (<em>E++</em>) of treatments, the individual
 d<sub>i</sub> effects were combined using weighted averages
 and a random model analysis. A positive effect size indicates that
 abundance, richness, and biomass of arthropods were lower on expanded
 leaves compared to leaf rolls, whereas a negative effect size implies a
 lower abundance, richness and biomass of arthropods for the leaf rolls
 compared to expanded leaves. As a convention, <em>E++</em>
 values around 0.2 are considered weak effects, values around 0.5 are
 considered of moderate magnitude, values around 0.8 are considered strong,
 and <em>E++</em> larger than 1.0 are considered very strong
 (Rosemberg et al.<em>,</em> 2000). The cumulative effects were
 considered significant if the confidence intervals (95%) did not overlap
 with zero. All analyses were conducted in Metawin 3.0
 (Rosemberg<em>,</em> 2023).  
description: # From leaves to whole plants: effects of shelter-builders on arthropod
 communities are stronger in dry seasons
 [https://doi.org/10.5061/dryad.9s4mw6mqz](https://doi.org/10.5061/dryad.9s4mw6mqz) ## **Explanations for the raw data tabs can also be found in the last tab (called Metadata) of the available XLSX files** **Metadata** **Dataset descriptors** **1) Leaf level** | **Variables** | **Description** | **Example** | | :-------------------- | :----------------------------------------------------------------------------------------------------------------------------- | :--------------------------------- | | Plant species | Specific epithet of plant taxa | *Miconia ligustroides* | | Group | Treatments used in the experimental design | expanded leaves, leaf rolls | | Plant individual | *Miconia ligustroides* individual sampled | 1, 2 | | Arthropod morphotypes | Arthropod morphotypes found per plant individual. The morphotypes with an asterisk (\*) were found inside the natural shelters | Cicadellini sp. 1, *Omophoita* sp. | | Richness | Number of species found per individual plant | 2 | | Abundance | Number of arthropod individuals found per plant individual | 3 | | Biomass | Dry mass of arthropods found per plant individual | 0.0006 g |   **2) Plant level** | **Variables** | **Description** | **Example** | | :-------------------- | :----------------------------------------------------------------------------------------------------------------------------- | :---------------------------------- | | Plant species | Specific epithet of plant taxa | *Miconia ligustroides* | | Group | Treatments used in the experimental design | galled, non galled | | Plant individual | *Miconia ligustroides* individual sampled | 1, 2 | | Arthropod morphotypes | Arthropod morphotypes found per plant individual. The morphotypes with an asterisk (\*) were found inside the natural shelters | *Cephalotes pusillus*, *Frigga* sp. | | Richness | Number of species found per individual plant | 1 | | Abundance | Number of arthropod individuals found per plant individual | 2 | | Biomass | Dry mass of arthropods found per plant individual | 0.0004 g |