Harmful Algal Blooms and Worm Holes
With the violent dust bowl of the 1930’s the United States agriculture scene became one of total chaos. The sod busting practices combined with a series of weather patterns created a scenario that was called the worst agricultural disaster in the World to date. Curiously enough, it is being reported that we may be heading for the same scenario again, with the same area receiving less rainfall over a 42 month period than it did during the historic dust bowl of 80 plus years ago. It was because of issues such as water and soil conservation that several practices were begun over time. One such practice became the use of No- till farming practices.
No-till farming practices are not a new idea. The practice is reported to have been used by the Incas and Egyptians so we are in pretty good company! However, it is certain that the extent of No-till practices that we have today has never been experienced as it has been over the past 15 years, according to a Washington Post 2013 article. The United States farmer has been readily adapting the practice. This is in not small part due to the advancement of the Round Up Ready trait for seed that allowed the application of the chemical glyphosate over the growing crop to kill the weeds. To date we several crops that are generally called “Round Up Ready” including corn, soybeans, cotton, sugar beets, alfalfa, and canola. About 88 million acres had such practices used in 2010 and a reported 96 million acres in 2012, about 1/3 of all farm land.
Another late day field scouting session by the Chesapeake Bay. A gorgeous sunset on a gorgeous bay!
The issue of Blue Green Algae and Harmful Algal Blooms have come to the forefront of water quality. Being predominantly a phosphorous driven issue, the agriculture industry is responding to the issue of nutrient management and guidelines are being written by those within the EPA, state government, and NGO’s . I have had the privilege to work with some good people in these efforts. The need for clean, safe drinking water is the most vital of needs for a person, town, or city. With this, we will are seeing changes to the way nutrients are handled that will have deep implications to the ways of fertilizer, supply management, and nutrient handling.
It is because of this event on Lake Erie that work is now coming from Heidelberg University that is rather interesting, logical, and yet surprising. In a nutshell, no-till does a great job at holding soil in place. It allows plant residues to remain on the surface and act as a buffer to absorb the impact of rain while dispersing the energies of erosion when water begins to seek a lower elevation off of banks and hillsides, particularly what is called Highly Erodible Land (HEL). The Sodbuster Act of the 1985 Food Security Act gave guidelines on the best way to maintain such land and protect water in the process. There is no doubt that no- till hold soil, and helps to maintain the soil structure.. ..including soil water holding capacity, and the development of macropores from long-term weather trends, such as drought, as well the work of earthworms.
The Heidelburg Tributary Loading Program is a long term study done by the Heidelberg University. Being the only study of its kind in the entire Great Lakes basin, it has been doing water quality measurements since 1974, collecting in excess of 142, 000 samples. A truly amazing study. What has been found is that total phosphorus loads have decreased, drastically, since 1974. However, the levels from non-point sources have not changed much in the same 40 year period. Yet in the meantime, the adoption of no- till practices has been steadily increasing. Why are farm source phosphorous levels not decreasing? It is being theorized that the cracks, worm holes, and other macropores from the use of long- term no-till practices are allowing the soluble phosphorous to quickly make its way to drain tiles and corresponding streams. Flow charts plotting time and concentrations provide strong circumstantial evidence for this theory.
The adoption of no-till practices has been strong. It is also reported in an earlier referenced text that the adoption of cover crops stood at 10 million acres across the United States. Perhaps we need to shift more of our focus to cover cropping as it will provide active root systems, the use of fallow time soil moisture, and in the process, use more of the soluble phosphorous. Otherwise, may we may need to go back to pulling out the moldboard plow every now and again to break up such quick ways of exit from the soil profile? What goes around may, in fact, come around.
Thank you for reading!