Mediterranean silvoarable systems in France
Description of system
The high seasonal variability of rainfall in the Mediterranean areas of southern France limits arable yields. There are periods of high rainfall in the autumn, and periods of water shortage in the spring and summer. In this situation, in areas where there are deep soils, that are able to retain water, silvoarable agroforestry (tree lines within the field) can improve water infiltration, limit soil evaporation, and limit crop water requirements.
Initial stakeholder meeting
The first meeting of the stakeholder group was help on 2 October 2014, and included visits to INRA Mauguio experimental station and the silvoarable systems at Restinclières. The research at Mauguio includes varietal selection of cereals. The systems at Restinclières include combinations of cereals with walnut, cereals with poplar and vineyard systems. The farmers who attended perceived that the key positive aspects of silvoarable agroforestry were income diversity, crop production, enhancement of biodiversity and wildlife habitats, and soil conservation. Key negative issues related to the business opportunity, cash flow, and crop losses from slugs, and wild deer and boars. A potential area for research is the selection of durum wheat varieties suited to agroforestry conditions.
If you would like to know about the activity of this group, please contact Dr Marie Gosme (firstname.lastname@example.org) at INRA.
Download the initial stakeholder report
An initial report was produced in October 2014.
Download the initial research and development protocol
This stakeholder group has produced two protocols: the first is focused on the selection of durum wheat varieties for agroforestry and the second is focused on weed management in silvoarable systems.
Download the system descriptions
Two system description reports providing an update on the selection of durum wheat varieties and weed management were produced in January 2016.
In the first report, Marie Gosme and Dominique Desclaux describe the lessons learnt from screening durum wheat cultivars for their suitability in agroforestry systems in Mediterranean France. Up to 45 cultivars were compared in control and agroforestry conditions in up to three sites for up to three seasons. Crops under agroforestry conditions received between 40 and 75% of the light available in unshaded areas. Mean yields were low in 2015, were about 1.9 t/ha in 2016 and 2.7 t/ha in 2017. The cultivars showed large variability in their suitability for agroforestry conditions with yield differences in agroforestry compared to full sun conditions ranging from -62% to +77 %. Old varieties and varieties based on populations were not systematically more adapted to agroforestry than newer or pure-line cultivars.
In the second report, Delphine Mézière and colleagues at INRA in Southern France measured the effect of the tree-rows within silvoarable systems on the species and abundance of weeds, relative to open field conditions, over 2015 and 2016. Herbicide use was limited to a single post-winter spray. In the barley crop in 2015, on average about seven weed species/m² were found in the arable section of the agroforestry plot, compared to six species/m² in the open arable field. The number of weed individuals was lower in the agroforestry arable crop (about 50/m2) than in the open field (about 75/m2). With a pea crop in 2016 there was some evidence that the weed abundance in the crop was higher in the crop margin (next to the tree row) than in the centre of the arable alley.