Assessment of biodiversity and agronomic parameters in two Agroforestry vineyards

Abstract

Sustainability of agricultural production systems is nowadays considered as a major challenge to face. Viticulture is particularly affected by environmental issues, especially because of its consumption in pesticides. Besides, the social demand in environment-friendly products is increasing, and the reputation of wines produced under Protected Denomination of Origin (PDO) is also built on the specificity of natural characteristics and resources such as soil, which has to be preserved. Biodiversity loss is largely admitted among the scientific community, and landscape simplification is known as a major driver in this process. Agroforestry, which combines trees with crops, could be a seducing response to biodiversity loss in agro-ecosystems, but the possibility of negative interactions between trees and vines (competition for water, nutrients, light) has to be considered. The Vitiforest project aims to assess south west of France agroforestry vineyard plots by spatializing different parameters in the domain of agronomy, ecology, micro-climate and economy. Field measurements were undertaken at different distances from the intercropped lines of trees in two agroforestry vineyard plots, in order to test potential effects of the trees. Arthropods were collected periodically with pitfall traps (for ground-dwelling individuals) and with D-vac system (aspiration of vine leaves). Pest insects (Empoasca vitis) were collected by specific yellow sticky traps. Data collected to describe biodiversity in these agroforestry systems was total arthropods abundances, abundances per order, carabidae richness and abundances. Nitrogen status was assessed by using Greenseeker® device, through the NDVI index. Our observations show that intercropped trees have no direct effects on vine nutrition. Slight effects on pests insects repartition were found, but these effects are inconstant according to experimental site and year of observation. The same trend is observed for arthropods abundances in the plots.