Predictive Ecological Engineering for Landscape Ecosystem Services and Sustainability – PEERLESS

The first pillar evaluates the impact of agronomic practices and landscape arrangements on production losses caused by the crop pests in five different French agricultural zones. The second pillar analyses on one hand, inter-specific interactions at the parcel and landscape levels to determine the most relevant floral and animal species involved in the biological control of pests, and on the other hand, the population dynamics of pests and of their main natural enemies depending on the characteristics of the landscape. The third pillar design strategies of area-wide-management that optimize pest control service, agricultural production and farmer outcomes. It is based on the evaluation of the distribution crop and semi-natural habitat in landscape scenarii in which the population dynamics of pests and their natural enemies are simulated with mechanistic models. These scenarii are finally optimized base on their agronomic, ecological, environmental and economic performances,

From an academic point of view, the first results on the agronomic and ecological factors governing the interactions between pests and their enemies and spatial distribution of their populations suggest that semi-natural habitats little impact the regulation of crop pests under the current conditions of agricultural productions. However, these results contribute to the understanding of ecological processes in the agro-ecosystem. They confirm the negative impact of agricultural practices on the beneficial and they suggest a strong compartmentalization of the biodiversity between the semi-natural habitats and the crops, which finally exchanged fairly.
From an applied point of view, the project assesses the impact of agro-ecological zones such as spontaneous hedgerows or flowering strips on the pest biological control. This assessment is partly conducted in collaboration with the agricultural advisers.

PEERLESS contribute to the structuring of a French scientific network in the field of agroecology and to the achievement of the ECOPHYTO action plan. It also contributes to the development of open reference databases for i) the molecular identification of beneficial groups of high agricultural importance (syrphids, hymenoptera parasitoids, carabids), ii) the establishment of their trophic link with agricultural pests and iii) the crossing of agronomic practices with their ecological impacts.

The scientific issues already published in PEERLESS are of interests for large audience disciplinary journals in ecology [1, 2] and academic journals at interfaces between economy, ecology and agronomy [3, 4].
Numerous experiments are conducted in collaboration between PEERLESS partners and should result in next joint publications [5-7].

1. Derocles, S. et al. (2014) Molecular analysis reveals high compartmentalization in aphid–primary parasitoid networks and low parasitoid sharing between crop and noncrop habitats. Molecular Ecology, 23, 3900-3911.
2. Maalouly, M., Franck, P. and Lavigne, C. (2015) Temporal dynamics of parasitoid assemblages parasitizing the codling moth. Biological Control, 82, 31-39.
3. Memmah, M. et al. (2015). Metaheuristics for agricultural land use optimization. A review. Agronomy for Sustainable Development, 35, 975-998.
4. Martinet, V. (2014). The economics of the food versus biodiversity debate. European Association of Agricultural Economists, Ljubljana, 26-29/08/14.
5. Walker, E. et al. (2014), Estimation of demographic parameters of an insect pest in apple-orchards landscape, from genetic data. International Statistical Ecology Conference. Montpellier, 02/07/14
6. Memmah, et al. (2014) Agricultural land use optimisation using many-objective preference-inspired co-evolutionary algorithm. International Conference on Metaheuristics and Nature Inspired Computing, Marrakech, 27-31/10/14
7. Botelho Costa, M. et al. (2015) Impact of flowering strips on pests, pest enemies and pest predation and parasitism in apple orchards. INNOHORT, ISHS international symposium, Avignon, 8-12/06/15.

With the shift towards a reduced reliance on external inputs in agriculture, identifying management options that enhance the provision of ecosystem services has become a critical issue. Pest control resulting from the activity of naturally present predators and parasitoids is frequently cited as an important service that could reduce pesticide use as targeted by the French 2018 Ecophyto governmental action. However, the link between management options, pest control level and ultimately crop yield is poorly understood. The PEERLESS project aims to identify alternative management strategies that enhance the crop protection service provided by functional biodiversity and ultimately to optimize agricultural systems, at local and landscape scales, for economic viability and sustainability. PEERLESS brings together six partners organisations with extensive expertise in agronomy, spatial ecology, ecology of interactions and public economy. The project combines: (i) an empirical assessment of naturally occurring crop protection from weed and insects pests in annual (wheat-oilseed rape rotations) and perennial (apple orchards) systems across a broad range of landscape and agronomic situations; (ii) ecological engineering with an assessment of alternative plant protection system to improve crop protection at the local scale; (iii) an in-depth study of the structure of trophic networks; and, (iv) population dynamics of key pests and their regulators in case study areas. These components will support the parametrisation of spatially-explicit, predictive models to (v) test the effect of landscape patterns of alternative local and landscape management strategies on pesticide use, pest control, crop yield and farmer income and (vi) identify landscape scale viable management strategies to control insect and weed pests.