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Editor's
NOTE
In addition to analyzing data from our
research trials and developing new domestic
and international research initiatives,
Don reviews dozens of research studies each
week. He'll present the most interesting
of his findings every week on the web site. |
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Field margins, the areas along the edges of crop fields
that are untilled and characterized by non-crop plant
species, are important both ecologically and often agronomically.
In densely inhabited areas such as many areas of Europe,
field margins are an important part of wildlife habitat.
Farmland bird populations have shown marked declines
in the last 40 years in Britain as a result of agricultural
intensification. If the same studies were carried out
in the US the same conclusion would likely be drawn.
Field margins have been shown to be important foraging
areas for birds, particularly in winter, and can be
managed such that they provide nesting sites as well.
In France, the art of hedge design on the margins of
crop fields is known as bocage, a reflection of its
cultural importance. Field margins can be designed so
that larger wildlife habitat areas can be connected,
so that they function as corridors for migrating wildlife.
Field margins can provide important overwintering sites
and both temporary and permanent habitat for organisms
that are beneficial to agriculture. Important predators
such as carabid beetles and staphylinid beetles and
spiders depend on untilled natural areas such as field
margins. These arthropods are voracious consumers of
crop pests. “Beetle banks”, raised strips
planted with tussock forming grasses within crop fields,
have been promoted in Britain. Beetle banks favor the
recolonization of crop fields by beetles in the spring,
promoting biological control of pests.
Riparian areas, the areas next to waterways, are particularly
important ecologically. Often, the vast majority of
species in an area are concentrated in riparian zones.
These areas are important for filtering out agricultural
nutrients and other chemicals before they reach aquatic
systems. In aquatic systems, agricultural nutrients
become pollutants. Pesticides, even organically certified
ones, when they reach aquatic systems, become hundreds
and even thousands of times more powerful as killing
agents.
The source for this research brief was a special
issue of Agriculture, Ecosystems & Environment (Elsevier
Science) Volume 89, Issues 1-2. The issue is dedicated
to agricultural field margins.
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