Utilisation of agri-environment scheme habitats to enhance invertebrate ecosystem service providers

The impact of habitat management (project-managed, farmer-managed or organic), quantity (proportion of uncropped land) and spatial configuration of habitats (arranged as strips or blocks) on the density and biomass of invertebrate functional groups was studied at the farm (100-ha block) and plot scale. At the farm scale, invertebrate abundance and biomass per unit area of uncropped land, responded positively to the presence of project-managed habitats for a number of invertebrate groups (including parasitoids and chick food). The abundance of different invertebrate functional groups varied considerably between habitat types; no single habitat provided the highest densities of all groups, suggesting that a diversity of habitats is beneficial for ecosystem service delivery. Grassy habitats supported the highest densities of predatory invertebrates, wild bird seed the most parasitoids and annual plant habitats the highest levels of chick food for farmland birds. Vegetation characteristics influenced total invertebrate biomass and levels of chick food, but not the total number of invertebrates or the abundance of those providing biocontrol.