About My Health Careers Internship MedBlogs Contact us
Medindia LOGIN REGISTER
Advertisement

Nitrogen Fertilizers Deplete Not Enrich Organic

by Medindia Content Team on October 31, 2007 at 6:17 PM
Font : A-A+

Nitrogen Fertilizers Deplete Not Enrich Organic

A new study by scientists from the University of Illinois contradicts the generally accepted theory that nitrogen fertilizers benefit the soil by building up organic carbon.

As part of their study, the team analyzed samples for organic carbon in the soil to identify changes that have occurred since the onset of synthetic nitrogen fertilization in 1955.

Advertisement

Findings revealed that after nearly five decades of massive inputs of residue carbon ranging from 90 to 124 tons per acre, all of the residue carbon had disappeared.

There had been a net decrease in soil organic carbon that averaged 4.9 tons per acre and regardless of the crop rotation, the decline became much greater with the higher nitrogen rate, said Saeed Khan from the UoI.
Advertisement

"It is truly fortunate that researchers over the past 100 years have been diligent in collecting and storing samples from the U of I Morrow Plots in order to check how management practices have affected soil properties," said Khan.

Co-researcher Tim Ellsworth said they were quite surprised to find that corn growth and yields had been about 20 percent lower during the past 50 years for the north (continuous corn) than for the south (corn-oats-hay) end of the Morrow Plots, despite considerably greater inputs of fertilizer nitrogen and residues.

The Morrow Plots are America's oldest experimental field.

Study co-author Charlie Boast, also from the University of Illinois, said that findings were consistent with previous studies showing a consistent decline in organic carbon in fertilized soil.

"In numerous publications spanning more than 100 years and a wide variety of cropping and tillage practices, we found consistent evidence of an organic carbon decline for fertilized soils throughout the world and including much of the Corn Belt besides Illinois," said Boast.

Study co-author Richard Mulvaney said the findings had troubling implications for corn production due to the widespread use of yield-based nitrogen recommendations since the 1970s.

"The one- size-fits-all approach was intended to minimize the risk of nitrogen deficiency as insurance for high yields. Unfortunately, the usual result is over-fertilization because of the assumption that the fertilizer supplies more nitrogen than the soil. The opposite is true in most cases, and especially for the highly productive soils of the Corn Belt that receive the highest nitrogen rates," he said.

"The rates have been progressively inflated over the years by yield increases from agricultural advances such as better varieties and higher populations," added Khan.

The study, "The Myth of Nitrogen Fertilization for Soil Carbon Sequestration" appears in the November/December 2007 issue of the Journal of Environmental Quality.

Source: ANI
VEN/C
Advertisement

Advertisement
News A-Z
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Advertisement
News Category
What's New on Medindia
Cochlear Implants may Consequently Drive Hearing Loss
E-cigarettes Use Linked to Erectile Dysfunction
Memory Loss - Can it be Recovered?
View all

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
Organic Foods Azotemia (High Blood Nitrogen Levels) 

Recommended Reading
Organic Foods
Organic Foods are produced by the 'natural method', without the use of chemicals like pesticides, ....
Azotemia (High Blood Nitrogen Levels)
Azotemia is a condition characterized by high blood nitrogen levels, leading to acute renal failure....

Disclaimer - All information and content on this site are for information and educational purposes only. The information should not be used for either diagnosis or treatment or both for any health related problem or disease. Always seek the advice of a qualified physician for medical diagnosis and treatment. Full Disclaimer

© All Rights Reserved 1997 - 2021

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use