DOI: 10.5061/dryad.mkkwh719g
title: Elevation and grassland cover shape natural enemy communities in Kenyan maize crops

description: Natural enemies, including arthropod predators and parasitoids, provide
 essential pest control services in agricultural systems by reducing pest
 populations below harmful levels. However, studies examining how natural
 enemies respond to environmental gradients, such as elevation and grass
 cover, are limited in sub-Saharan Africa. This study investigates the
 effects of elevation (1200–1950 meters above sea level) and grassland
 cover in the surrounding landscape (2–30%) on natural enemy communities in
 maize fields in western Kenya over two sampling seasons. We selected maize
 plots along gradients of elevation and percentage of grassland and
 conducted field surveys using pitfall traps to assess the diversity and
 composition of natural enemies.  Natural enemy diversity,
 richness, evenness, abundance, and community structure were compared
 across gradients using generalized linear models (GLMs) and Non-Metric
 Multidimensional Scaling (NMDS). Overall, ants were the most abundant
 group. Lower elevations supported more diverse and evenly distributed
 natural enemy communities, while higher elevations were dominated by
 Myrmicaria ants.  Grassland cover exhibited limited overall
 effects, showing a marginally positive impact on species evenness during
 the second sampling season, which contributed to changes in community
 composition. The dominance of Myrmicaria ants at high elevations and low
 grass cover may reduce overall pest control resilience, emphasizing the
 need for integrated pest management strategies with a focus on multiple
 landscape variables and responses to climate change. Our findings
 highlight the importance of environmental gradients in shaping natural
 enemy biodiversity in agricultural fields with implications for pest
 control in western Kenya.
description: # Data from: Elevation and grassland cover shape natural enemy communities
 in Kenyan maize crops ## Data:
 genera_elevation_grasscover_season1_table.csv Datasets documenting natural
 enemy communities recorded from 16 smallholder farms in western Kenya
 (Bungoma, Homabay, and Vihiga counties) during the first sampling season
 in 2019. * plot_id: Unique identifier assigned to each farm. *
 actual_elevation_masl: Measured elevation of the plot, recorded in meters
 above sea level (masl). * elevation_category_masl: Elevation of the plot
 grouped into six predefined categories (1200, 1350, 1500,1650, 1800, and
 1950 masl). * actual_grasscover_percentage: Percentage of grass cover
 surrounding the plot, calculated using high-resolution satellite imagery
 within a 1 km radius buffer. * grasscover_category_percentage: Grass cover
 percentage grouped into three predefined categories: 10%, 20%, and 30%. *
 Columns F to GL: Counts of natural enemies recorded, including ants,
 spiders, crickets, beetles, and other genera. ## Data:
 genera_elevation_grasscover_season2_table.csv Datasets documenting natural
 enemy communities recorded from 24 smallholder farms in western Kenya
 (Bungoma, Homabay, and Vihiga counties) during the second sampling season
 in 2020. * plot_id: Unique identifier assigned to each farm. *
 actual_elevation_masl: Measured elevation of the plot, recorded in meters
 above sea level (masl). * elevation_category_masl: Elevation of the plot
 grouped into six predefined categories (1200, 1350, 1500, 1650, 1800, and
 1950 masl). * actual_grasscover_percentage: Percentage of grass cover
 surrounding the plot, calculated using high-resolution satellite imagery
 within a 1 km radius buffer. * grasscover_category_percentage: Grass cover
 percentage grouped into three predefined categories: 10%, 20%, and 30%. *
 Columns F to GL: Counts of natural enemies recorded, including ants,
 spiders, crickets, beetles, and other genera.