Abandonement of coffee agroforests increases insect abundance and diversity

Abstract

Shade coffee including many tree species is known to support generally high biodiversity. Due to low coffee prices on the world market, many farmers have abandoned their farms, thereby creating a new ecosystem type, which has attracted increasing interest for biodiversity conservation. Here we used pyrethrum knockdown samples to compare the arthropod community on coffee plants of six traditionally managed coffee agroforests with those of six abandoned coffee agroforests in coastal Ecuador. We investigated eight randomly selected coffee shrubs per site, six of them inside and two at the edge. All arthropods were identified to orders and beetles to morphospecies. We additionally sampled the vegetation to test for vegetation-mediated effects on the arthropod community. The number of arthropod individuals was higher in abandoned than managed coffee, driven by the abundance of Arachnida, Blattaria, and Heteroptera, and higher in the edge than in the centre of the abandoned agroforests. Higher arthropod abundance appeared to be closely related to arthropod diversity, as shown for beetles (r = 0.79, n = 96). Contrary to expectations, predator-prey ratios in managed agroforests was as high as in the abandoned ones.In conclusion, abandonment of coffee agroforests greatly encourages arthropod communities, in particular in the habitat edges, and therefore, should be considered in landscape management for conservation.

Diet, microhabitat use, and thermal preferences of Ptychoglossus bicolor (Squamata: Gymnophthalmidae) in an organic coffee shade plantation in Colombia

“…These microhabitat preferences may derive from the substantial availability of food and space resources found at these coffee fields and the ability of P. bicolor to avoid environments that are not suitable around these plantations. Organic coffee agrosystems and coffee shade plantations have been recognized as a potential refuge for biodiversity, mainly because these environments have special properties (like an abundant layer of organic material undergoing continuous nutrient cycling by a rich macroinvertebrate fauna) and greatly overlap with global biodiversity hotspots (Hardner & Rice 2002;Perfecto et al, 2007;Richter et al, 2007).…”

Composition and functional groups of epiedaphic ants (Hymenoptera: Formicidae) in irrigated agroecosystem and in nonagricultural areas

“…This is due to the diversifi cation of microhabitats, a result from the presence of annual scrubs, favoring stability in the agroecosystem (Bardgett & Cook, 1998). In this way, seasonal plots may be functioning in a similar way to abandoned areas and that such are functioning as biodiversity refuges (Richter et al, 2007), since ants are less active during the hottest and driest season of the year (Rico-Gray et al, 1998).…”

Where to sample? Ecological implications of sampling strata in determining abundance and impact of natural enemies of the coffee berry borer, Hypothenemus hampei

“…Despite the organic production system used, the plantation was not shaded and was surrounded by other crops. Intensification of the coffee system has been reported to lead to low insect biodiversity (Perfecto et al, 2003;Richter et al, 2007).…”