pollinator populations fall. Three basic viewpoints from which bee loss impact can
be analyzed and extrapolated are as follows:
1. Direct crop yield reduction
2. Economic impacts
3. Human health impacts
4.3.1 Direct Crop Yield Reduction
One approach to calculating the impact of pollinator loss is by measuring crop output
and land use in relation to what we know about pollinator dependency and yield
improvements. Just like prior yield improvement studies, however, it is important to
remember that different crops in different regions rely on pollinators to different
extents.
In a 2009 study attempted to estimate global crop losses should animal pollination
fail. Using extensive 1961–2006 data from the Food and Agricultural Organization
of the United Nations, pollination dependency was calculated for 87 important
crops. Though about 75% of flowering crops benefit from pollinators to varying
degrees, only 10% depend fully on pollinators for seed and fruit production; these
dependent crops account for an estimated 2% of global agricultural production by
2009. If those crops with the highest pollinator dependency failed due to lack of
pollination, global crop production would decrease by an estimated 8%.
However, the 8% crop impact is merely an estimate of a direct reduction and does
not represent economic or nutritional effects, so the given calculation is an abstraction. As it turns out, indirect negative impacts can be significant. If the yield of a land
unit is reduced, then more land would be turned over to agriculture, resulting in yet
more pollinator habitat loss and other related ecological threats. The estimated
increase in cultivated land area necessary to compensate for the production deficit
was several times higher than normal, especially in the developing world, which
already supports two-thirds of global agricultural land [33].
A 2013 study centered in the European Union approached the problem with a
different method and reached a different conclusion. Instead of calculating pollinator
dependency of individual crops, scientists assessed “relative pollination potential,”
which is the relative potential or capacity of an ecosystem to support crop pollination. When insects begin foraging, their host ecosystems or “land cover” such as
forest edges have the potential to increase yields of adjacent pollinator-sensitive
crops; this potential represents the wild pollinator’s economic value and can be
measured as yield contribution or the cost savings when compared to replacing with
managed honey bees. Using existing foraging data of wild bees with short flight
distances, pollination potential was linked to regional European crop production
statistics. Representing data limited to those pollinating insects with short foraging
distances, the crop production deficit was estimated to be 2.5%. However, as more
data of species with increased flight range were added to the map, pollination
potential would increase up to 25%.
1 Understanding, Conservation, and Protection of Precious Natural Resources: Bees
29
be analyzed and extrapolated are as follows:
1. Direct crop yield reduction
2. Economic impacts
3. Human health impacts
4.3.1 Direct Crop Yield Reduction
One approach to calculating the impact of pollinator loss is by measuring crop output
and land use in relation to what we know about pollinator dependency and yield
improvements. Just like prior yield improvement studies, however, it is important to
remember that different crops in different regions rely on pollinators to different
extents.
In a 2009 study attempted to estimate global crop losses should animal pollination
fail. Using extensive 1961–2006 data from the Food and Agricultural Organization
of the United Nations, pollination dependency was calculated for 87 important
crops. Though about 75% of flowering crops benefit from pollinators to varying
degrees, only 10% depend fully on pollinators for seed and fruit production; these
dependent crops account for an estimated 2% of global agricultural production by
2009. If those crops with the highest pollinator dependency failed due to lack of
pollination, global crop production would decrease by an estimated 8%.
However, the 8% crop impact is merely an estimate of a direct reduction and does
not represent economic or nutritional effects, so the given calculation is an abstraction. As it turns out, indirect negative impacts can be significant. If the yield of a land
unit is reduced, then more land would be turned over to agriculture, resulting in yet
more pollinator habitat loss and other related ecological threats. The estimated
increase in cultivated land area necessary to compensate for the production deficit
was several times higher than normal, especially in the developing world, which
already supports two-thirds of global agricultural land [33].
A 2013 study centered in the European Union approached the problem with a
different method and reached a different conclusion. Instead of calculating pollinator
dependency of individual crops, scientists assessed “relative pollination potential,”
which is the relative potential or capacity of an ecosystem to support crop pollination. When insects begin foraging, their host ecosystems or “land cover” such as
forest edges have the potential to increase yields of adjacent pollinator-sensitive
crops; this potential represents the wild pollinator’s economic value and can be
measured as yield contribution or the cost savings when compared to replacing with
managed honey bees. Using existing foraging data of wild bees with short flight
distances, pollination potential was linked to regional European crop production
statistics. Representing data limited to those pollinating insects with short foraging
distances, the crop production deficit was estimated to be 2.5%. However, as more
data of species with increased flight range were added to the map, pollination
potential would increase up to 25%.
1 Understanding, Conservation, and Protection of Precious Natural Resources: Bees
29