The United Nations Food
and Agriculture Organization (FAO) today highlighted the publication of a new
study that quantifies, for the first time, how much crop yields depend on the
work of bees that unknowingly fertilize plants as they move from flower to
flower.
In doing so, the agency says bees may have a key role to
play in improving the production of some two billion smallholder farmers
worldwide and ensuring the food security and nutrition of the world's growing
population.
"What do cucumbers, mustard, almonds and alfalfa
have in common?" asked FAO in a press release. "On the surface, very
little; but there is one thing they share: they all owe their existence to the
service of bees."
The agency notes that for centuries, this tiny striped
helper has labored the world's fields without winning much recognition for its
many contributions to food production. Wild bees, in particular, seemed doomed
to slog in the shadow of their more popular cousin - the honeybee - whose day
job of producing golden nectar has been far more visible and celebrated.
But
FAO says bees of all stripes are finally getting their moment in the sun. The
paper, published in the magazine Science, makes the case that
ecological intensification - or boosting farm outputs by tapping the power of
natural processes - is one of the sustainable pathways toward greater food
supplies.
Food security strategies worldwide could therefore
benefit from including pollination as integral component, experts say.
"Our research shows that improving pollinator
density and diversity - in other words, making sure that more and more
different types of bees and insects are coming to your plants - has direct
impact on crop yields," said Barbara Gemmill-Herren, one of the FAO
authors of the report.
"And that's good for the environment and for food
security," she stressed, adding that it is beneficial to actively preserve
and build habitats in and around farms for bees, birds and insects to live
year-round.
Focus on developing countries
In the field study
coordinated by FAO, scientists compared 344 plots across Africa, Asia and Latin
America and concluded that crop yields were significantly lower in farming
plots that attracted fewer bees during the main flowering season than in those
plots that received more visits.
When comparing high-performing and low-performing farms
of less than two hectares, the outcomes suggest that poorly performing farms
could increase their yields by a median of 24 per cent by attracting more
pollinators to their land.
The research also looked at larger plots and concluded
that, while those fields also benefited from more pollinator visits, the impact
on yields was less significant than in the smaller plots - probably because
many bees have a harder time servicing large fields, far from their nesting
habitat. But a diversity of bees, each with different flight capacities, can
make the difference.
This suggests that bee diversity offers benefits both for
small-holder farmers in developing countries, and for larger farms.
Why it matters
The research comes
at a time when wild bees are threatened by a multitude of factors and managed
bee populations can't keep up with the increasing number of plots that grow
pollination-dependent crops.
Climate change poses yet another problem: "Bees will
struggle with the higher temperatures," explained Nadine Azzu, Global
Project Coordinator in FAO's Plant Production and Protection Division, who also
worked on the report. "Plus, flowers in some parts of the world are now
opening at different times than they used to, and the bees are not there to
pollinate," she said.
This means finding ways to keep pollinators buzzing
around the farm year-round is becoming even more important.
Previously unstudied
Pollinators - such as bees, birds and various types of
insects that fly, hop or crawl from one flower to another - have for centuries
been the invisible helpers of farmers worldwide.
Different types of bees have distinct tastes and roles to
play in the food system. Bumble bees, for example, are one of the few types of
bees that can successfully pollinate tomatoes, which heavily rely on buzz
pollination to bear fruit.
Honey bees, in turn, are important because they are the
least picky in their choice of flowers- and there are many of them, in each
hive, even though their more discerning wild bee cousins are more effective in
fertilizing the plants they're attracted to.
The study shows that for smallholdings, crop yield
increased linearly with increased visits to the flowers that were being
tracked. Pollination was the agricultural input that contributed the greatest
to yields, beyond other management practices.
This holds promise for one of the major agricultural
challenges of our time: How to help smallholders produce more without hurting
the environment.
How
to attract bees
The report also found that attracting pollinators to
farms is not as easy as planting for the season and waiting for them to arrive.
Maintaining habitat and forage resources all year long is
key to wooing pollinators and keeping them on the land for longer periods of
time. This can be done by planting different trees and plants that flower at
different times in the year, for example.
Maintaining flowering hedge rows around the farm, and
mulch on the ground that bees can hide under, are additional recommended
tactics to attract them, as is reducing the use of pesticides.
The key to getting the best yields probably lies in a mix
of managed pollination services - that is, installing bee hives in plots at
flowering time - and wild pollination, experts say.
And the latter will require farmers and policy makers to
take a closer look at the ecosystems that surround farms.
"The take away from our study is that bees provide a
real service and should be taken into account when we plan food security
interventions," said Ms. Azzu. "And the best part is: their service
is free."
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