Modifications o Agricultural Settings
In order to support agricultural uses of land, many hydrologic modifications
have been made. Many of these modifications make waterways more
vulnerable to pollutants. Should the modifications have been made?
Are there ways to minimize the threats given the existing modifications?
looks very different now than it did when the European settlers
first arrived. Many of the initial changes made by settlers were
made to support agriculture. were drained, prairies
were plowed, and forests were cleared to make way for farm fields.
Once the fields were in place, rivers were straightened, , moved,
constricted by levees, or even wiped out to avoid flooding valuable
crops. Irrigation systems were installed to take water into dry
areas turning them into pockets of profitable land. All of these
modifications changed the natural "plumbing system", or
of the land. Two of the most common modifications
are and agricultural drainage wells.
Puddles may be good for the water and wildlife, but they are
not good for crops. Many Iowa farmers have drained their land using
one of two systems, tiling or agricultural drainage wells.
Tiling is an
underground drainage system that uses "pipes" to collect
water from low lying areas and move it to a waterway. With tiling,
drainage from farm fields shoots directly into waterways, taking
pollutants along with it. Tiled fields cover much of the state of
Iowa, including land with large animal confinements located on or
near it. When accidents happen, manure or farm chemicals have a
straight shot into waterways.
Iowas unique , farmers also rely on agricultural
drainage wells. The wells drain water off the land and directly
into underground , one of the states primary
sources of drinking water. Any pollutant that makes its way into
one of these wells has far-reaching, perhaps irreversible effects.
modifications have made it possible to farm 90% of the land in Iowa,
producing a net profit of over $2.5 million in 2000. No one is suggesting
that all the land should be converted back to its natural state,
but there are some things that can be done to minimize the negative
effects of the .
- Expand programs
that encourage farmers to restore important natural areas.
- Enact laws
to regulate activities on tiled fields and around agricultural
and time farm field chemical and manure applications to reduce