Austral Ecology (2014) 39, 198-203

Anahí Fernandez, Alejandro G. Farji-Brener and Patricia Satti (2014)
Moisture enhances the positive effect of leaf-cutting ant refuse dumps on soil biota activity
Austral Ecology 39 (2), 198-203
Abstract: Soil biota activity in arid lands is often limited by the availability of water and organic matter. We experimentally explored whether small changes in soil moisture affect the activity of soil biota in external refuse dumps of the leaf-cutting ant Acromyrmex lobicornis, one of the most important sources of organic matter in a semi-arid land of north-western Patagonia. We estimated CO₂ consumption in refuse dumps and in adjacent, non-nest soil samples at two moisture levels, after 48 and 72 h. Soil biota activity, estimated by respiration rates, was up to 160 times greater in refuse dumps than in adjacent, non-nest soils. Activity of soil biota in non-nest soil did not change through time and was not affected by moisture. Conversely, soil biota increased their activity in refuse dump samples only at high moisture condition after 72 h. As the activity of microorganisms is key for soil nutrient generation and availability, refuse dumps may be considered as 'islands of fertility' for plants. This effect may be especially important after sporadic spring rainfalls, when the beneficial effect of refuse dumps on soil biota is enhanced. In addition, as refuse dumps generate several times more CO₂ than non-nest soils, nest areas may be considered also as hot spots of CO₂ emissions. These results illustrate the potential importance of ant nests for nutrient cycling, maintenance of plant cover and carbon balance in arid ecosystems.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Alejandro G. Farji-Brener

Research topic(s) for pests/diseases/weeds:
environment - cropping system/rotation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Acromyrmex lobicornis		Argentina