TY - JOUR

T1 - Functional shifts of grassland soil communities in response to soil warming

AU - Briones, Maria Jesus Inglesias

AU - Ostle, Nick

AU - McNamara, Niall P.

AU - Poskitt, Jan

PY - 2009/2

Y1 - 2009/2

N2 - organisms critical to the global carbon cycle. Temperate grassland ecosystems, contain large, diverse and active soil meso- and macrofauna decomposer communities. Understanding the effects of climate change on their ecology offers a first step towards meaningful predictions of changes in soil organic carbonmineralisation.We examined the effects of soil warming on the abundance, diversity and ecology of temperate grassland soil fauna functional groups, ecosystem net CO2 flux and respiration and plant above- and below-ground productivity in a 2-year plant–soil mesocosm experiment. Low voltage heating cable mounted on a framework of stainless steel mesh provided a constant 3.5 C difference between control and warmed mesocosm soils.Results showed that this temperature increment had little effect on soil respiration and above-ground plant biomass. There was, however, a significant effect on the soil fauna due to warmer conditions and increased root growth, with significant decreases in the numbers in the large oligochaete groups and Prostigmata mites and the re-distribution of enchytraeids to deeper soil layers. Functional groupsexhibited individualistic responses to soil warming, with the total disappearance of epigeic species in the case of the ecosystem engineers and an increased diversity of fungivorous mites that, together, produced significant changes in the composition and trophic structure of the fauna community.The observed switch towards a fungal driven food web has important implications for the fate of soil organic carbon in temperate ecosystems subjected to sustained warming. Accordingly, soil biology needs to be properly incorporated in C models to make better predictions of the fate of SOC under warmer scenarios.

AB - organisms critical to the global carbon cycle. Temperate grassland ecosystems, contain large, diverse and active soil meso- and macrofauna decomposer communities. Understanding the effects of climate change on their ecology offers a first step towards meaningful predictions of changes in soil organic carbonmineralisation.We examined the effects of soil warming on the abundance, diversity and ecology of temperate grassland soil fauna functional groups, ecosystem net CO2 flux and respiration and plant above- and below-ground productivity in a 2-year plant–soil mesocosm experiment. Low voltage heating cable mounted on a framework of stainless steel mesh provided a constant 3.5 C difference between control and warmed mesocosm soils.Results showed that this temperature increment had little effect on soil respiration and above-ground plant biomass. There was, however, a significant effect on the soil fauna due to warmer conditions and increased root growth, with significant decreases in the numbers in the large oligochaete groups and Prostigmata mites and the re-distribution of enchytraeids to deeper soil layers. Functional groupsexhibited individualistic responses to soil warming, with the total disappearance of epigeic species in the case of the ecosystem engineers and an increased diversity of fungivorous mites that, together, produced significant changes in the composition and trophic structure of the fauna community.The observed switch towards a fungal driven food web has important implications for the fate of soil organic carbon in temperate ecosystems subjected to sustained warming. Accordingly, soil biology needs to be properly incorporated in C models to make better predictions of the fate of SOC under warmer scenarios.

KW - Community structure

KW - SOC

KW - Soil invertebrates

KW - SOM

KW - Trophic food webs

UR - http://www.scopus.com/inward/record.url?scp=58149503764&partnerID=8YFLogxK

U2 - 10.1016/j.soilbio.2008.11.003

DO - 10.1016/j.soilbio.2008.11.003

M3 - Journal article

AN - SCOPUS:58149503764

VL - 41

SP - 315

EP - 322

JO - Soil Biology and Biochemistry

JF - Soil Biology and Biochemistry

SN - 0038-0717

IS - 2

M1 - 41

ER -