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Land use management influence changes in biodiversity beyond the targeted species. Management practices in coffee plantations have shifted from coffee growing below accompanying (shade) trees, to intensified monocultures in which coffee grows fully exposed to the sun. Anthropogenic disturbance causes changes in species composition relative to adjacent natural patches and reduces their biotic heterogeneity. Here, we assessed the impact of coffee plantation management practices on the taxonomical, phylogenetic and functional composition of ant communities, an ecologically dominant group and crucial biological pest controller in these agroecosystems. We hypothesized that shade‐grown coffee plantations would harbour ant communities similar to those of nearby forest patches, but dissimilar to those of intensified monocultures. We surveyed ant diversity in eight shade‐grown coffee farms, eight intensive coffee monocultures and eight forest patches. We used a combination of active and passive sampling methods over two field campaigns spanning 6 months. Our results support our hypothesis for all diversity dimensions. Additionally, ant communities in intensified monocultures were taxonomically and functionally, but not phylogenetically, more homogeneous than those found in forest patches and shade‐grown plantations. Synthesis and applications. Our findings support the idea that practices in shade‐grown coffee plantations buffer the impoverishment of multiple diversity dimensions after forest conversion. Additionally, we identified that leaf‐litter depth and number of twigs mitigate ant diversity loss which, in turn, can favour the presence of potential biocontrol agents. By assessing and integrating multiple biodiversity dimensions into management strategies, farmers and interested parties can minimize future biodiversity and ecosystem service loss.

Guilds and diversity of ants in three land uses from a coffee landscape at Cauca -Colombia. In the last 50 years, Colombian coffee production has undergone a great transformation from traditional plantations grown below the forest's shade, to vast extensions of coffee plantations consisting of free exposition to sun. These systems reduce native biodiversity and its associated ecosystem services. Simultaneously, shaded coffee plantations operate as potential shelter of such biodiversity, favoring its dispersal in the landscape, because they offer high-quality habitat for the movement of wild organisms through natural vegetation relicts. Therefore, it is important to document its biological value. In Colombia, Cauca department is the fourth coffee producer and although its cultures were mainly based on the model of using trees' shade on coffee shrubs, in last 10 years, sun coffee plantations have doubled their extension in this department and have almost equated the shaded coffee extension. Thus, it is necessary to document if these land use changes at landscape scale may derivate in consequences for the wild biota dwelling these productive systems. Given the above considerations, and in order to test for the biological importance of coffee plantations, the present study compares the effect of three land uses (sun coffee, shaded coffee and natural vegetation patches; eight of each one) in terms of ants' species richness and the abundance of their trophic guilds at Caldono municipality, between August 2015 and January 2016. Captures were carried out with pitfall traps, mini-Winkler sacs and direct capture. We found that ants' richness was higher in natural vegetation patches, followed by shaded coffee plantations and sun coffee plantations, in these last ones, the omnivore-generalist ants were more abundant, and ground-foraging arboreal ants were less abundant. We found that shaded coffee plantations, despite belonging to a transformed land use, have greater similarity with some natural vegetation patches. Using only ants from the lowest stratum (soil and understory), our findings confirm that shaded coffee plantations maintain an important part of the ant diversity of the locality, while sun coffee plantations offer less habitat quality to it. El café (Coffea arabica L. Rubiaceae) es una especie vegetal de gran importancia comercial en Colombia, cuya producción ubica este país como el tercero a nivel mundial, después de Brasil y Vietnam (ICO, 2017). Con el paso de los años, las variedades de los cafetos sembrados en Colombia -que en condiciones naturales de su sitio originario en África, crecen en el estrato bajo de bosques-, fueron progresivamente reemplazadas por variedades desarrolladas para resistir el pleno sol, sembradas a cielo abierto con arbustos bajos, en densidades de hasta 10 000 por hectárea, y ocasionalmente acompañadas por una o dos especies vegetales, también productivas (Borrero, 1986;Armbrecht, 2016). Esta forma de producción proviene de una concepción de agricultura industrial, que dep...

Introduction: Adequate biological identification is fundamental for establishing integrated pest management programs and identifying the trophic and mutualist relationships that can affect pest population dynamics. Aphids are the main pest of pepper Capsicum spp. (Solanaceae) crops in Southwestern Colombia, due to their role as vectors of viruses. However, the identification of aphid species is complex, limiting the investigations performed to address their interactions with other organisms. Ants and aphids present a facultative mutualistic relationship, that promotes the growth of hemipteran colonies, for this reason, the study of the ecological mutualistic association between aphids and ants is important. Objective: The main objective was to discriminate the aphid species present in commercial crops of Capsicum spp., and to identify the ant community that attends the aphid colonies and its effects on the size of the aphid colonies. Methods: Aphid species, and their ant mutualist, were collected from Capsicum annuum and Capsicum frutescens, in the Cauca valley, Southwestern Colombia. We use the DNA barcoding approach to identify aphid species, and the ants were identified by morphology‐based taxonomy. To evaluate the effect of ant care on the size and structure of aphid colonies, generalized linear models were calculated using as the response variables the total number of aphids for each colony and the proportion of nymphs. Results: The aphid species that attack pepper crops, are: Aphis gossypii and Myzus persicae (Hemiptera: Aphididae), with A. gossypii being the species that interacts with ants (19 ant species). A. gossypii colonies attended by ants had larger sizes and more nymphs per colony, than those not attended. Conclusions: Although the aphid-ant interaction is not species-specific, it is necessary to consider its role in the propagation of viral diseases in peppers and to determine how this interaction may affect regional biological control strategies.

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