Although genetically modified crops are getting so much flak today, there seems to be some instances where they may provide some positive benefits in some areas related to farming and the environment. According to an article on the sciencedaily website, a team of researchers found out that genetically modified herbicide tolerant crops may have helped reduce herbicide runoff in watersheds and improve water quality in a four-year span.
A four-year study conducted by soil scientists Martin Shipitalo and Lloyd Owens, and agricultural engineer Rob Malone at the USDA-ARS’s North Appalachian Experimental Watershed near Coshocton, OH, aimed to compare the relative losses of residual and contact herbicides when applied at normal rates. Both types of herbicides were applied to seven small watersheds that was planted with genetically modified Liberty Linked corn and Roundup Ready soybean. Residual herbicides are the type of herbicides more commonly used for most organic crops while contact herbicides began its use with the introduction of genetically modified herbicide resistant crops.
The researchers noted that losses of contact herbicides were usually much less in surface run-off than for those areas where residual herbicides were used as a percentage of the amount of herbicide that was used. When averaged for all the soybean crop years, glyphosate runoff was about one half that of alachlor and one seventh of metribuzin, two of the residual herbicides that can be replaced by the contact herbicide Roundup. In the same study, another contact herbicide, glufosinate (Liberty) has an average runoff loss one fourth that of atrazine, a type of residual herbicide for corn crops that it can replace.
Residual herbicide runoff in different bodies of water has been a constant problem in areas of the country where farming is practiced. These residual herbicides find their way in nearby rivers, streams and lakes as well as water reservoirs and build up concentrations that can exceed drinking water standards. This poses a problem if those bodies of water are also used as sources of drinking water. This contamination can lead to increased costs when treating the water supply and may even result for the need to look for alternative sources of water supply.
The study showed that replacing residual herbicides with that of contact herbicides while planting genetically modified herbicide tolerant crops may help avoid contaminating watersheds and water supply sources from excessive herbicide surface runoffs.
Source: American Society of Agronomy. "Herbicide-tolerant Crops Can Improve Water Quality." ScienceDaily 23 April 2008. 23 April 2008 .