Soil Functional Biodiversity
Lead organisation: Wageningen University
WP2 aims to assess how soil biodiversity (specific, functional, community) is impacted by reduced tillage systems.
WP2 will be carried out in experimental field sites. Soil biodiversity will be assessed through 2 main groups i.e. earthworms and nematodes. Microorganisms will be assessed indirectly through their activity (WP3).
The contribution of nematodes to different processes occurring in soil (e.g. decomposition of organic matter, mineralization, detoxification of actually, nematodes directly act on food production due the presence of some phytoparasites nematode. In the other hand, nematodes are used as bioindicators as they are strongly impacted by environmental constraints (Bongers and Ferris, 1999). However, there are few data recording the impact of tillage system on nematodes (Villenave et al., 2009)...pollutants) is important because of their abundance and trophic diversity (Yeates et al., 1993); Phytoparasitic nematodes can directly influence food production by reducing yields. On the other hand, nematodes are used as bioindicators as they are strongly impacted by environmental constraints. However, there is few data describing the impact of tillage system on nematode.
Earthworms represent the largest biomass of soil fauna (Lavelle and Spain, 2001). Because of the large modifications they can cause to their environment, they are recognized as "ecosystem engineers" (Jones et al., 1994). It is well known that they earthworms act on many soil functions including structuration (impact on water movement), OM dynamics (impact on nutrient cycling), and some recent studies have demonstrated that they act on N20 production (Giannopoulos et al., 2010). Therefore, earthworms directly influence ecosystem services such as food production (Jones et al., 1994) and should also affect GHG. In addition, earthworms are used as bioindicators because they are strongly impacted by environmental constraints such as agricultural practices (Pérès et al., 2009), and many studies have reported the negative impact of tillage on earthworm communities.
Description of work
In WP2, selected experimental sites will be studied.
Regarding the French sites, earthworm sampling will be done in Kerguehennec station in Agronomic trial (code FKA), Transfer trial (code FKT) and Organic farming trial (code FKO). Data will be analyzed according to datasets previously obtained in these trails. Nematode will be sampled in Agronomic trial (code FKA) and Organic farming trial (code FKO).
About Dutch sites, earthworm sampling will be done in all sites.
Earthworms will be sampled using the ISO method (23611-1) adapted to regional conditions (Bouché, 1977; Cluzeau et al., 1998). They will be studied through their community structure (density, biomass, specific structure and ecological groups).
Nematodes will be sampled using ISO method (23611-4). They will be studied through community structure at family level, abundance of different trophic groups and several index reflecting soil functioning particularly, Maturity Index, Enrichment Index and Structure Index (Ferris et al., 2001).