Limitation of nesting resources for ants in Colombian forests and coffee plantations

Abstract

1. This study examines limitation of nesting resources for leaf-litter and twig-nesting ants as a mechanism of diversity loss across an intensification gradient of coffee production in Colombia. Twelve farms were selected and classified into four management types: forest, polygeneric shade coffee, monogeneric shade coffee, and sun coffee (unshaded coffee monocultures).2. At each of the farms, four treatment subplots were established at the corners of each of 10 25 m 2 plots: (i) twig augmentation (adding 10 empty bamboo twigs); (ii) litter augmentation (tripling existing litter profile); (iii) twig and litter augmentation; and (iv) no manipulation control, for a total of 480 subplots. A twig addition experiment was also performed on coffee bushes.3. The results showed significantly more ant colonies in the forest and monogeneric shade coffee litter augmentation plots after 4 months. Litter-nesting ant species richness was higher in all three shade systems than in the sun coffee. The identities of ants nesting on coffee bushes were different from those in the soil level litter. Fewer species nested in bamboo twigs placed in litter in the most intensive systems.4. More ants nested in the resource addition treatments, and more ant species were found in forested habitats; however, a single mechanism cannot explain the observed patterns. It was concluded that a combination of bottom-up and top-down effects might lead to the loss of associated fauna with the intensification of these agroecosystems.

Size matters: nest colonization patterns for twig‐nesting ants

“…Thus, it is difficult to say that differences in nest limitation are due to the agroecological context, as previous studies in coffee plantations have found that the community of twig‐nesting ants are limited by nesting resources (Armbrecht et al. ), as are ants in natural ecosystems (Kaspari ; Powell et al. ).…”

The influence of temperature and fine‐scale resource distribution on resource sharing and domination in an ant community

“…This is especially the case for ant communities, in which inter-specific competition is important and numerical dominance enables resource acquisition ( Palmer, 2003 ). Differences in ant abundance between sites may be driven by a variety of biotic and abiotic factors, including nest availability ( Hölldobler & Wilson, 1990 ;Armbrecht et al , 2006 ), microhabitat variation ( Palmer, 2003 ), differences in vegetation ( Ribas et al , 2003 ), and other food resources ( Sanders & Gordon, 2003 ). Differences in ant abundance between sites may be driven by a variety of biotic and abiotic factors, including nest availability ( Hölldobler & Wilson, 1990 ;Armbrecht et al , 2006 ), microhabitat variation ( Palmer, 2003 ), differences in vegetation ( Ribas et al , 2003 ), and other food resources ( Sanders & Gordon, 2003 ).…”

Evaluating factors influencing heterogeneity in agroforestry adoption and practices within smallholder farms in Rift Valley, Kenya

“…However, agricultural landscapes where small-scale farming is significant have been noted for their potential for tree (Lengkeek et al, 2006;Kindt et al, 2007), soil biota (Barrios et al, 2012), bird (Komar, 2006), insect (Armbrecht et al, 2006;Perfecto et al, 1996), mammal (Gallina et al, 1996), and orchid (Solis-Montero et al, 2005) biodiversity conservation in the tropics.…”