Set of interactions and transformations operating within agroecosystem biotechnical systems. Biological regulation integrates the concepts of natural regulation, pollination and biological control. There are of two types:
- Spontaneous biological regulation: ecosystem self-organization allowing, in response to disturbances, to preserve the previous equilibrium conditions or adapt the system by bringing it into a new state of equilibrium.
- Induced biological regulation: all biological interactions which result from agricultural practices and activities defined by humans to achieve equilibrium levels (biological thresholds), in order to fulfil the agronomic objectives.
Nowadays, many research projects aim at better understanding biological regulation services which are biological control of pests, plants and domestic animals, pollination and control of biological invasions, in order to favour them at different scales (plot, farm, landscape). On a given landscape, biodiversity at all scales favours these biological regulation services.
Predation of aphids by ladybirds is an example of spontaneous biological regulation of agroecosystems when it occurs without having been voluntarily favoured by the farmer (natural regulation). This biological regulation becomes induced when it results from the farmer setting up semi-natural elements in order to favour beneficial organisms (of which ladybirds belong to) to limit his pesticide use. It then corresponds to conservation biological control.
Regarding livestock farming, farmers can also release mini wasps (Hymenoptera) which are parasitoids of flies present in buildings and harmful to both livestock and breeders. This augmentative biological control also corresponds to an induced biological regulation.
Biological regulation is therefore a real asset available to farmers. By understanding it, retaining it, amplifying it or provoking it, they adopt agroecological practices and thus increase the resilience of their farming systems.
References to explore
Lavorel S. (coord.), Sarthou J.P (coord.) et al. 2008. Intérêts de la biodiversité pour les services rendus par les écosystèmes. Chap. 2. Agriculture et biodiversité. Expertise scientifique collective Inra – ESCo “Agriculture et biodiversité”. 266p.
Prévost, P. 2000. La régulation biologique un concept intégrateur de la connaissance agronomique. Courrier de l’environnement de l’INRA(39), p.27-38.
Rusch, A. 2010. Analyse des déterminants des attaques de Meligethes aeneus (Coleoptera, Nitidulidae) et de sa régulation biologique à l’échelle d’un paysage agricole : contribution à l’amélioration de la protection intégrée du colza. Thèse : Ecosystèmes. Paris : AgroParisTech.