Date:
2018/06/14
Time:
13:45
Room:
A1 Wilhelm
Conserving biodiversity in agricultural landscapes: a win-win for farmer and wildlife?
(Oral and Poster)
Thijs Fijen
, Jeroen Scheper
, David Kleijn
SEE PEER REVIEW
Although agriculture depends critically on biodiversity-based ecosystem services such as insect pollination, conservation of biodiversity in agricultural landscapes has seen little uptake by the agricultural sector. We argue that this is largely because we lack knowledge on the relative importance of pollination compared to conventional agricultural inputs. Using the real-world variation in pollination and agricultural management of 36 commercial leek seed production fields in France and Italy, we show that the benefits of having more wild pollinators is at least as large as the benefits of management enhancing plant quality. Although the bulk of the pollination services was delivered by a few abundant bumblebee species, a diverse pollinator community replaced, or complemented these dominant species, depending on the crop variety. We furthermore show that crop yields are equally large, or even larger with 50% less agricultural inputs, and are consistently larger with more pollinator visits. Both the dominant and the scarce crop pollinators were positively correlated with cover of semi-natural habitats and the regional pollinator species pool, illustrating the benefit of conserving natural elements in agricultural landscapes. However, the dominant crop pollinators were largely absent in the landscape just prior to leek flowering, possibly because they are specialized in exploiting mass-flowering (crop) plants. Identifying where these important pollinators acquire their resources in agricultural landscapes throughout their flight period is essential to convince the agricultural sector to conserve biodiversity in agricultural landscapes and how to take measures.
INTRO: The effects of insect-pollination on crop yield and quality can be as high as the effects of conventional production inputs. This is probably emphasized in areas where pollination service is most insufficient due to the negative effects of conventional intensive agriculture on pollinator populations. This study demonstrates the benefits of good insect-pollination in leek seed production. The results show that use of agricultural inputs could be reduced without compromising yield. Pollination service can also be enhanced by increasing the cover of natural and semi-natural habitats in agricultural landscapes. The results help convincing farmers and all agricultural sector of the importance of conserving pollinators.
MERITS: The results that show the benefits of good insect-pollination for crop yield are very important in convincing policy-makers and farmers of the need for change in agriculture. The study was conducted in 36 fields, which is a good sample size. Monitoring of pollinator species and flower visits provides interesting details about the complementarity among pollinator species, and about the changes in their abundance during summer. The abstract is clear and well-written.
CRITIQUE: The abstract is short (much longer abstracts are allowed) and tell very little about the methods of the study. I would be interested to know at least in which country the study was done. Besides pollinator visitation data from leek fields, you had data on pollinators in the landscapes surrounding the fields. From what habitats this data is, and how it was collected? Little more details about the methods would make this a perfect abstract.
DISCUSSION: It would be interesting to know if insect-pollination affected also yield quality. As you studied seed production, the effects of good pollination on seed germination would be most relevant.