Collembolan communities as bioindicators of land use intensification

Abstract

International audienceSpringtail communities (Hexapoda: Collembola) were sampled in the Morvan Nature Regional Park (Burgundy, France) in six land use units (LUUs) 1 km(2) each, which had been selected in order to cover a range of increasing intensity of land use. Human influence increased from LUU 1 (old deciduous forest) to LUU 6 (agricultural land mainly devoted to cereal crops), passing by planted coniferous forests (LUU 2) and variegated landscapes made of cereal crops, pastures, hay meadows, conifer plantations and small relict deciduous groves in varying proportion (LUUs 3-5). Sixteen core samples were taken inside each LUU, at intersections of a regular grid. Species composition, species richness and total abundance of collembolan communities varied according to land use and landscape properties. Land use types affected these communities through changes in the degree of opening of woody landscape (woodland opposed to grassland) and changes in humus forms (measured by the Humus Index). A decrease in species richness and total abundance was observed from old deciduous forests to cereal crops. Although the regional species richness was not affected by the intensification gradient (40-50 species were recorded in every LUU), a marked decrease in local biodiversity was observed when the variety of land use types increased. In variegated landscapes the observed collapse in local species richness was not due to a different distribution of land use types, since it affected mainly woodland areas. Results indicated the detrimental influence of the rapid afforestation of previous agricultural land, which did not afford time for the development of better adapted soil animal communities

Soil health: looking for suitable indicators. What should be considered to assess the effects of use and management on soil health?

“…Decaëns et al (2004) observed that conversion of native ecosystems in the Colombian tropical savanna into pastures did not change the taxonomic richness and composition of organisms, while the conversion of Brazilian rainforest caused deep changes in the macrofauna community, including substitution of native earthworms by exogenous species. Even under temperate conditions, the total abundance and species composition decreased with the intensification of land use (Ponge et al, 2003). Similarly, Baretta et al (2007) reported that the diversity, abundance, and biomass of earthworms in native or reforested Brazil Pine (A. angustifolia) forests were sensitive enough to distinguish the sites under different land-use.…”

“…The most representative organisms normally studied as indicators of soil health belong to the mesofauna, which lives in soil macropores and spaces in the soil-litter interface, feeding on fungal hyphae and organic matter, and thus taking part in nutrient cycling and soil aggregation (Lavelle and Spain, 2001). Studies under different environmental conditions have shown that some springtail species are good indicators of soil health (Ponge et al, 2003;Baretta et al, 2008). The macrofauna includes bigger soil organisms which sometimes are active in soil functioning (Lavelle et al, 2006).…”

Colêmbolos (Hexapoda: Collembola) como bioindicadores de qualidade do solo em áreas com Araucaria angustifolia

“…Estão entre os invertebrados mais abundantes no solo, podendo sobreviver também na serapilheira, árvores, litoral marinho e na água doce (Bellinger et al, 2007). Embora estudos com diversidade de colêmbolos no solo tenham aumentado muito nas últimas décadas, no Brasil e no mundo (Sautter & Santos, 1991;Sautter et al, 1998;Culik & Zeppelini Fillho, 2003;Ponge et al, 2003;Sousa et al, 2004;Zeppelini Filho & Bellini, 2004;Cutz-Pool et al, 2007), considerando o crescente interesse na compreensão dos processos ecológicos dos quais esses organismos participam nos ecossistemas, observam-se diversas limitações, tais como: a falta de taxonomistas disponíveis e de métodos adequados para capturar tais organismos (Zeppelini Filho & Bellini, 2004).…”

“…A utilização dos atributos químicos e microbioló-gicos do solo como variáveis ambientais explicativas no entendimento do funcionamento do solo, aliada à quantificação da diversidade de invertebrados edáficos como os colêmbolos, é um ponto de partida importante para entender os processos ecológicos de decomposição e ciclagem de nutrientes no solo (Chauvat et al, 2003;Ponge et al, 2003;Cutz-Pool et al, 2007). A diversidade de colêmbolos tem sido usada como bioindicador de intervenções antrópicas, bem como da qualidade do solo (Sautter & Santos, 1991;Culik et al, 2002;Chauvat et al, 2003;Ponge et al, 2003;Cutz-Pool et al, 2007).…”

Mesofauna do solo em diferentes sistemas de uso da terra no Alto Rio Solimões, AM

“…Acari Oribatida já foram relatados em alta concentração em áreas com condições climáticas adversas (Ribeiro & Schubart 1989, Franklin et al 1997 e em áreas de pastagem na Amazônia (Dantas 1979, Oliveira 1993 infl uencia os processos de decomposição e embora sejam os mais abundantes componentes da mesofauna, não são os mais importantes agentes de fragmentação do folhedo (Franklin et al 1996(Franklin et al , 2004. Os colêmbolos são importantes como bioindicadores do solo devido a sua sensibilidade ao estresse ambiental, principalmente acidez do solo e composição química (Sautter et al 1994, Ponge et al 2003. Estudos com Collembola como bioindicadores revelaram que a presença de cobertura verde, matéria orgânica em decomposição e sistema radicular infl uenciaram o aumento da sua população (Sautter & Santos 1991).…”