An article from 2012
Articles
Decline of bees forces China's apple farmers to pollinate by hand
The
decline of wild bees in China threatens more than just its apple and
pear harvests, says pollination expert Dave Goulson.
2
October, 2012
In
the last 50 years, the global human population has nearly doubled,
while the average calories consumed per person has increased by about
30%.
To
cope with the ever growing demand for food, more land has been
brought into agricultural production, mainly by clearing forests, and
farming has become much more intensive. Fertilisers, pesticides, and
development of new plant varieties have allowed farmers to increase
the average yield of food per hectare to increase by 130% in the same
period.
It
is obvious that this pattern cannot go on for ever; we will run out
of forests to clear, and we cannot squeeze ever more food from the
same area of land. There are cracks beginning to show; highly
intensive farming may not be sustainable in the long term.
Globally,
about 75 billion tons of soil is lost every year, washed away or
blown out to sea after ploughing. Three hundred and twenty million
hectares of land have been affected by a build up of salt due to
irrigation practices. Roughly 40% of all agricultural land is now
degraded in one way or another.
The
role of bees and pollinators
Farming
and human health depend upon the ecosystem services provided by wild
organisms; worms, woodlice, millipedes and a host of other creatures
which help with soil formation, forests to produce oxygen, prevent
soil erosion and regulate water flow, birds to eat insect pests,
flies and beetles to break down animal dung, bees and other
pollinators to pollinate crops.
Modern
farming threatens to eradicate these organism, and so undermine
itself.
Pollination
provides one of the clearest examples of how our disregard for the
health of the environment threatens our own survival. About 75% of
all crop species require pollination by animals of some sort, often
by bees, but sometimes by flies, butterflies, birds or even bats.
Crop
pollination by insects has been estimated to be worth $14.6 billion
to the economy of the USA and £440 million a year to the UK. Some
pollination is done by domesticated honeybees, but the bulk of
pollination of most crops is done by wild insects, including many
species of wild bee such as bumblebees.
In
the UK, for example, recent studies suggest that about one-third of
pollination is delivered by honeybees, the rest being carried out by
a range of wild insects. These animals need undisturbed places to
nest, and flowers to feed on when the crops are not flowering.
However,
bee diversity has declined markedly in Europe, with many species
disappearing from much of their former range, and some species going
extinct. The UK alone has lost three species of native bumblebee, and
six more are listed as endangered. Four bumblebee species have gone
extinct from the whole of Europe, and there is good evidence for
similar declines in North America and China.
Pollinating
animals fly in to our fields to pollinate crops from surrounding wild
areas, but if there are no wild areas, or if the crops are doused in
insecticides, then pollination will suffer and yields will decline.
China’s
hand-pollinated orchards
Evidence
from around the world points to falling and increasingly
unpredictable yields of insect-pollinated crops, particularly in the
areas with the most intensive farming. Where crops are grown in vast
fields, there are not enough insects to go around. If insecticides
are sprayed too frequently, then vital pollinators cannot survive.
The
most dramatic example comes from the apple and pear orchards of south
west China, where wild bees have been eradicated by excessive
pesticide use and a lack of natural habitat.
In recent years,
farmers have been forced to hand-pollinate their trees, carrying pots
of pollen and paintbrushes with which to individually pollinate every
flower, and using their children to climb up to the highest blossoms.
This is clearly just possible for this high-value crop, but there are
not enough humans in the world to pollinate all of our crops by
hand.
There
are simple solutions; studies in Europe and North America have found
that planting strips of wildflowers on farms, and leaving patches of
natural vegetation such as forests, can greatly boost pollinator
populations. These practices can also increase populations of natural
predators, decreasing the need for pesticide sprays.
With
a little effort it is perfectly possible to grow food and look after
the environment. In fact, taking a long term view, this is probably
the only way to grow food, for otherwise there is a danger that
farming will collapse.
Without
bees, our diets would be depressingly poor. We would be forced to
survive on wind-pollinated crops; wheat, barley and corn, and little
else. Imagine shops without raspberries, apples, strawberries, peas,
beans, courgettes, melons, tomatoes, blueberries, pumpkins and much
more.
Bees
and other insects have provided free pollination for our crops for
millennia. They will continue to do so if we learn to recognise their
importance and return the favour by providing them with what they
need to survive.
We
need to recognise that the health and wellbeing of our children
depends upon us preserving a healthy environment, and that to do so
requires that we show some respect for the myriad of wild animals and
plants with which we share the world
Dave
Goulson is professor of biological science at Stirling University in
the UK
Co-incidentally I covered this in my interview on access radio today,for what its worth. Another entry in my Facebook note on bee die-offs.
ReplyDeletehttps://www.facebook.com/notes/kevin-hester/bee-die-offs-and-how-they-will-effect-us-read-the-comment-section-for-many-more-/10202929767977885