title: Loss of soil (macro)fauna due to the expansion of Brazilian sugarcane acreage.
abstract: Land use changes (LUC) from pasture to sugarcane (Saccharum spp.) crop are expected to add 6.4Mha of new sugarcane land by 2021 in the Brazilian Cerrado and Atlantic Forest biomes. We assessed the effects of these LUC on the abundance and community structure of animals that inhabit soils belowground through a field survey using chronosequences of land uses comprising native vegetation, pasture, and sugarcane along a 1000-km-long transect across these two major tropical biomes in Brazil. Macrofauna community composition differed among land uses. While most groups were associated with samples taken in native vegetation, high abundance of termites and earthworms appeared associated with pasture soils. Linear mixed effects analysis showed that LUC affected total abundance (X(2)(1)=6.79, p=0.03) and taxa richness (X(2)(1)=6.08, p=0.04) of soil macrofauna. Abundance increased from 411±70individualsm(-2) in native vegetation to 1111±202individualsm(-2) in pasture, but decreased sharply to 106±24individualsm(-2) in sugarcane soils. Diversity decreased 24% from native vegetation to pasture, and 39% from pasture to sugarcane. Thus, a reduction of ~90% in soil macrofauna abundance, besides a loss of ~40% in the diversity of macrofauna groups, can be expected when sugarcane crops replace pasture in Brazilian tropical soils. In general, higher abundances of major macrofauna groups (ants, coleopterans, earthworms, and termites) were associated with higher acidity and low contents of macronutrients and organic matter in soil. This study draws attention for a significant biodiversity loss belowground due to tropical LUC in sugarcane expansion areas. Given that many groups of soil macrofauna are recognized as key mediators of ecosystem processes such as soil aggregation, nutrients cycling and soil carbon storage, our results warrant further efforts to understand the impacts of altering belowground biodiversity and composition on soil functioning and agriculture performance across LUC in the tropics.
authors.affiliation: Center for Nuclear Energy in Agriculture, University of São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP, Brazil; School of Global Environmental Sustainability & Department of Biology, Colorado State University, 80523, Fort Collins, CO, USA. Electronic address: andre.franco@colostate.edu.
authors.forename: André L C
authors.initials: AL
authors.lastname: Franco
authors.affiliation: Universidade Positivo, Rua Prof. Pedro de Souza 5300, 81280-330, Curitiba, PR, Brazil.
authors.forename: Marie L C
authors.initials: ML
authors.lastname: Bartz
authors.affiliation: Center for Nuclear Energy in Agriculture, University of São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP, Brazil.
authors.forename: Maurício R
authors.initials: MR
authors.lastname: Cherubin
authors.affiliation: Santa Catarina State University, Rua Beloni Zanin 680E, 89815-630, Chapecó, SC, Brazil.
authors.forename: Dilmar
authors.initials: D
authors.lastname: Baretta
authors.affiliation: Department of Soil Science, "Luiz de Queiroz" College of Agriculture, University of São Paulo, Av. Pádua Dias 11, 13418-900, Piracicaba, SP, Brazil.
authors.forename: Carlos E P
authors.initials: CE
authors.lastname: Cerri
authors.affiliation: Center for Nuclear Energy in Agriculture, University of São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP, Brazil.
authors.forename: Brigitte J
authors.initials: BJ
authors.lastname: Feigl
authors.affiliation: School of Global Environmental Sustainability & Department of Biology, Colorado State University, 80523, Fort Collins, CO, USA.
authors.forename: Diana H
authors.initials: DH
authors.lastname: Wall
authors.affiliation: Shell Technology Centre Houston, 3333 Highway 6 South, Houston, TX 77082, USA.
authors.forename: Christian A
authors.initials: CA
authors.lastname: Davies
authors.affiliation: Center for Nuclear Energy in Agriculture, University of São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP, Brazil.
authors.forename: Carlos C
authors.initials: CC
authors.lastname: Cerri
mesh_terms: D000383:Agriculture; D000818:Animals; D044822:Biodiversity; D001938:Brazil; D007313:Insecta / Q000502:physiology; D007448:Invertebrates / Q000502:physiology*; D009835:Oligochaeta / Q000502:physiology; D031786:Saccharum / Q000254:growth & development*; D012987:Soil / Q000737:chemistry*
chemical_list: D012987:Soil
keywords: Bioenergy crops; Land use change; Soil biodiversity