DOI: 10.5061/dryad.c866t1gjv
title: Data from: The role of tropical forest fragment vegetation in maintaining arthropod diversity and spillover to adjacent sugarcane fields

description: The degradation of forests in tropical agricultural landscapes has reduced
 biodiversity and may negatively affect ecosystem services. However, the
 role of forest fragments in the provision of ecosystem services for
 agroecosystems, such as biological control, is still not well understood.
 This study analyses the relationship between tree diversity and arthropod
 communities in forest fragments and adjacent sugarcane fields around
 Jaboticabal (São Paulo, Brazil) to evaluate the benefits of preserving
 Atlantic Forest fragments. We tested the hypotheses: (1) arthropod
 diversity and the abundance of key functional groups are favoured by tree
 diversity, (2) diversity and abundance of these functional groups in
 sugarcane fields depend on adjacent forests, and (3) the insect community
 composition of forest fragments and sugarcane fields is similar due to
 spillover effects. Arthropods were sampled in ten forest fragments over
 two years (2020 and 2022) using traps (Malaise, yellow pan) and direct
 tree sampling. We identified arthropods to morphospecies (2020) and family
 level (2022) and associated families to functional groups. We found that
 the quality of forest fragments, particularly tree species richness, was
 positively related to forest arthropod richness and frequency (occupied
 samples) of functional groups involved in ecosystem services such as
 predators but also of phytophagous insects. There was also a strong
 positive correlation between insect family richness and functional groups
 of forest fragments and adjacent sugarcane fields, indicating potential
 spillover and spatial connectivity between habitats. Although insect
 community composition was significantly different between forest fragments
 and sugarcane fields, NMDS ordination revealed partial overlap of family
 communities, suggesting many shared taxa in both habitats. This study
 highlights the importance of forest fragments in preserving insect
 biodiversity and related ecosystem services in tropical agricultural
 landscapes and advocates for the conservation and restoration of these
 habitats. However, the benefits in terms of crop damage reduction and
 yields remain to be confirmed.
description: The study was conducted in 10 fragments of Atlantic Forest (Mata
 Atlântica) and adjacent sugarcane fields in the municipality of
 Jaboticabal, São Paulo state, Brazil. Five fragments were located on
 shallow slopes (plateau fragments) and five were remnants of riparian
 forest close to rivers and streams (gallery fragments). Plateau fragments
 typically exhibited a higher cover of shrub and liana species compared to
 river valley fragments. River valley fragments are protected as Permanent
 Preservation Areas (APPs), in particular to preserve the water quality of
 piped water catchment areas. Arthropods were sampled in April 2020 and in
 August 2022, using direct and indirect (trap) collection methods. Three
 fragments had to be replaced in 2022 due to access problems and forest
 fires. In each forest fragment, we collected data in a randomly selected
 50 m x 20 m plot, 5 m from the edge. Arthropods were also sampled in
 sugarcane fields adjacent to the forest fragments. In
 2020, a preliminary study was conducted focusing on arthropod biodiversity
 in forest fragments. We defined woody plants larger than 5 cm in diameter
 at breast height as trees and identified them by species. Sampling was
 limited to 20 trees associated with five 1 m² subplots in each plot (tree
 closest to each corner). We used a simple habitat quality index to
 characterize forest fragments. The index uses tree cover as a positive
 criterion and vine and grass cover as negative criteria. Cover was
 estimated as the vertical projection of plant organs above the ground
 using a scale from 0 to 1 with 0.1 intervals. The quality index was
 calculated as the sum of the three parameters, with liana and grass cover
 adjusted as negative values ​​and tree cover as positive values.
 In August 2022, a more detailed method was used to obtain more
 information about the characteristics of the plant and arthropod
 community. All trees in the 1000 m² plots were identified and insects were
 sampled from all trees during the dry season. On each tree, we carefully
 cut a randomly selected branch at a height of 2–5 m with long-reach
 pruning shears and manually captured all arthropods. The sampled
 arthropods were transferred to 70% diluted alcohol before identification.
 In 2020, insects and spiders were identified to the morphospecies level.
 In 2022, we identified the sampled insect individuals to the family level
 to obtain more information about taxonomic and functional groups, but we
 did not include spiders. We assigned all insects sampled in 2022 to the
 following functional groups, using knowledge of the life history feeding
 traits of most species in each family: parasitoids, predators, omnivores,
 and phytophagous arthropods. Families that could not be clearly assigned
 to a functional group were considered omnivores and ultimately removed
 from functional group analyses. For insects that switch diets between
 larval and adult stages, we used larval feeding behavior, since larvae
 generally have a higher demand for resources and are the main consumers in
 the life cycle. In 2022, we additionally used traps to
 sample flying insects. A Malaise trap was placed in each forest fragment
 plot. In sugarcane fields, we installed two yellow traps (42 x 28 x 8 cm)
 15 m apart and 5 m from the edge of the sugarcane field. Each trap was
 filled with 2 L of water and 10 drops of detergent before exposure for a
 period of 48 hours. Likewise, the insects were preserved in 70% alcohol,
 identified at the family level and classified into functional
 groups.
description: # Data from: The role of tropical forest fragment vegetation in
 maintaining arthropod diversity and spillover to adjacent sugarcane fields
 Dataset DOI: [10.5061/dryad.c866t1gjv](10.5061/dryad.c866t1gjv) ##### This
 dataset contains arthropod sampling and vegetation data collected in 2020
 and 2022 in forest fragments and adjacent sugarcane fields in Jaboticabal,
 São Paulo state, Brazil. 
 
 FILES AND DESCRIPTION 1\. 2020_-_Arthropod_collection.csv \- Arthropod
 abundance by morphospecies, collected by direct sampling of branches in
 forest fragments in 2020. ``` • Plot: sampling plot ID ``` • SubPlot: one
 of the 4 selected points in each plot ``` • Arthropod_Order: The order of
 collected arthropods • Arthropod_Family: The family of collected
 arthropods • Morphospecies: code assigned to each arthropod morphospecies
 ``` 
 
 2\. 2020_-_Plot_information.csv \- Data on forest vegetation, arthropods
 and quality index of the 2020 collection. ``` • Plot: sampling plot ID •
 Fragment_type: plateau or gallery • Quality_index: the calculated index
 based on tree, liana, and grass cover • Arthropod_morphospecies: arthropod
 morphospecies richness per plot • Insect_morphospecies: insect
 morphospecies richness per plot ``` 
 
 3\. 2022_-_Direct_collection.csv \- Frequency of insects identified at
 family/order level collected by direct sampling of branches in forest
 fragments in 2022.    • Plot: sampling plot ID ``` • Fragment_type:
 plateau or gallery • Number_of_tree_species: Number of tree species per
 plot • [Family names]: frequency of each group (number of occupied
 branches per fragment) • [Functional group]: The total frequency of each
 functional group ``` 
 
 4\. 2022_-_Plot_information.csv \- Forest vegetation information for 7
 plots that were maintained between years. ``` • Plot: sampling plot ID •
 Fragment_type: plateau or gallery • Quality_index_(2020): the calculated
 index based on tree, liana, and grass cover (2020) • Tree_species_(2020):
 number of tree species per plot (2022) ``` 
 
 5\. 2022_-_Trap_collection.csv \- Insect families collected in Malaise
 and yellow pan traps in 2022. ``` • Plot: sampling plot ID •
 Fragment_type: plateau or gallery • Habitat_type: sugarcane or forest •
 [Family names]: presence or absence of each family • [Functional group]:
 The total number of families in each functional group ``` NOTES \-
 “unidentified” = specimen collected but not identified beyond higher
 taxonomic level (e.g., order only). \- Plots differ between years: 10
 plots in 2020, but 3 were replaced in 2022 due to fire or access issues.
 \- The variable “Tree_species” (2022) was tested as an alternative to
 “Quality_index” (2020) in analyses. ## Code/software Excel, no specific
 software required.