Sowing strips of flowering plants has only ‘limited’ effect on pollination
Currently, in the UK, farmers receive extra subsidies for planting ‘pollinator-friendly’ strips of land next to crops, these are called ‘field margins’ or ‘set-aside’.
Conservationists have hailed these areas as a significant contribution to conservation effort.
Let us hope that those responsible for management of biodiversity conservation, indeed, the stewards of our ecosystems, are held to natural standards that benefit all species reliant on the ecosystem.
New research from Lund University in Sweden shows that the effect of the sown flower strips on pollination is limited and cannot compensate for the advantages of a varied landscape.
Many pollinating insects benefit from a small-scale agricultural landscape with pastures, meadows and other unploughed environments. In landscapes dominated by arable land, they lack both food and nesting places. Sown flower strips can increase the availability of food for pollinating insects, and are therefore assumed to benefit pollination.
Researchers at the Centre for Environmental and Climate Research at Lund University have studied how pollination varies in different agricultural landscapes, by placing pots with either wild strawberry or field bean in field borders. Plants that were placed in a small-scale agricultural landscape, with pastures and other unploughed environments, were better pollinated than plants in landscapes dominated by arable land.
The researchers also investigated how sown flower strips – flower plantings which farmers often create to benefit pollinators – affected pollination in the different landscape types. In landscapes dominated by arable fields, pollination increased adjacent to the flower strip. A few hundred metres further away, however, the sown flower strips had no effect on the pollination of wild strawberry and field bean. In more small-scale agricultural landscape, the sown flower strips instead reduced pollination of adjacent plants, likely because the increased amount of flowers resulted in competition among flowers for pollinating insects.
Researcher Lina Herbertsson said: “In our study, pollination was highest in small-scale agricultural landscape, with pastures, meadows and other unploughed habitats. Wild bees are important pollinators and manage better in a landscape with a lot of field borders and other unexploited environments. In intensively farmed landscapes, where such environments have disappeared, we can increase pollination, at least in the immediate vicinity, by sowing flowering plants to attract pollinating insects.”
Farmers can receive financial support to implement measures that promote biodiversity, some of which may also benefit pollinating insects. An evaluation is currently underway of the EU’s common agricultural policy, CAP, which among other things regulates the support for greening measures, aimed at reducing the climate impact of European agriculture and promoting biodiversity in the agricultural landscape.
She added: “Our study underlines the importance of carefully designing measures intended to increase biodiversity, in order to achieve the desired effect. The same measure could have a different impact in different places. If we want to increase pollination in varied agricultural landscapes, it seems to be a better strategy to restore and maintain pastures and meadows, and to manage field borders in a way that favours the local flora, rather than adding sown strips of flowering plants.”
Meanwhile, 29 wildlife organisations from across Europe have made a joint submission to the pollinator initiative consultation put out by the 28 member European Union.
It is estimated that 84% of EU crop species and 78% of wildflower species rely on insect pollination. The ecosystem service provided to the EU by pollinators is valued at €22 billion per year. Pollinators provide an excellent indicator of the health of our environment and underpin essential services.
The big area of common ground is developing a full EU Pollinator Strategy in collaboration with Member States to deliver:
- Remaining areas of wildflowers, semi-natural meadows, and existing High Nature Value agriculture maintained, supported and promoted.
- B-Lines/BeeLines enabling pollinators and other wildlife to disperse effectively and providing the conditions for populations to recover.
- Agri-environment schemes successfully deliver habitat for priority pollinator species.
- Pollinator species and habitats listed in the Habitats Directive in FCS.
- EU pesticide approval process and subsequent risk management ensures pollinator safety.
Matt Shardlow, chief executive of Buglife, who coordinated the response, said. “It was very pleasing to find such strong commonality of thought and support for pollinator across such a wide range of European charitable organisations. Hopefully, the EU will respond favourably to these ideas and help coordinate action to ensure the future of our pollinators.”
Full list of signatories: Buglife – The Invertebrate Conservation Trust, Butterfly Conservation Europe, Friends of the Earth Europe, Vlinderstitchting (Dutch Butterfly Conservation), Environmental Justice Foundation, River of Flowers, Conchological Society, Bumblebee Conservation Trust, Freshwater Habitats Trust, Wildlife Trusts, Client Earth, Wildfowl and Wetland Trust, Mammal Society, Save Butterfly World, Pollinis, A Rocha, Edinburgh Entomological Club, People’s Trust for Endangered Species, Plantlife, British Arachnological Society, RSPB, Bijenstichting (Dutch Bee Conservation), Badenoch & Strathspey Conservation Group, Amateur Entomologists’ Society, SOS Polinizadores (SOS Pollinators), Federation of Irish Beekeepers’ Associations, Vilde bier i Danmark (Danish Association for Native Bee Conservation), British Dragonfly Society, Butterfly Conservation
Further reference – Science Direct
Lina Herbertsson, researcher
Centre for Environmental and Climate Research, CEC, at Lund University
Tel: + 46 702-96 42 55