(Press-News.org) FAYETTEVILLE, AR - Determining and implementing orchard management practices that can improve soil organic matter is one of the primary goals of the USDA's National Organic Program. For producers in the southeastern United States, where interest in small-scale and organically managed orchards is growing, the challenge can be finding combinations of groundcover management systems and organic nutrient sources that can simultaneously improve soil quality. A new research study provides producers in the region with valuable information about effective organic orchard management practices in the Ozarks Highland and similar regions.
During the 7-year study, University of Arkansas researchers evaluated the impacts of groundcover management system and nutrient source on soil quality-related variables such as soil organic matter (SOM), soil bulk density, plant-available water, water-stable aggregation, saturated hydraulic conductivity, and water infiltration in an organically managed apple orchard. The scientists also compared soil quality in an organic apple orchard with those in an adjacent conventionally managed orchard. The orchards were located on highly weathered soil in the Ozark Highlands region of northwest Arkansas.
The scientists tested annual applications of municipal green compost, shredded office paper, wood chips, and mow-blow grass mulch groundcover management systems in combination with composted poultry litter, commercial organic fertilizer, or a nonfertilized control as a nutrient source. "The combinations were implemented to evaluate their ability to alter near-surface soil quality in a newly established, organically managed apple orchard in the Ozark Highlands region of northwest Arkansas," said Curt Rom, corresponding author of the study published in HortScience.
"Our analyses showed that the soil organic matter concentration in the top 10 cm averaged 1.5% across all treatments at orchard establishment in 2006, but by 2012, SOM concentration had increased in all GMS and more than doubled to 5.6% under green compost," the authors said. "Similarly, soil bulk density in the top 6 cm, which averaged 1.34 g·cm-3 among treatment combinations in 2006, decreased in all GMS by 2012."
With regard to fertilizers, green compost applied alone or in combination with commercial fertilizer had the largest estimated plant-available water among all treatment combinations.
Interestingly, analyses showed that many soil quality-related variables measured in the various organic groundcover management systems had "numerically greater values" compared with an adjacent conventionally managed orchard on the same soils.
"Implementation of these groundcover management systems appear to provide apple producers in the Ozark Highlands and similar regions a tangible means of meeting National Organic Program requirements for improving soil quality concurrent with production of certified organic crops," Rom noted, adding that the research findings also have implications for conventionally managed orchards, where maintaining or improving soil quality is a management goal.
INFORMATION:
The complete study and abstract are available on the ASHS HortScience electronic journal web site:
http://hortsci.ashspublications.org/content/50/2/295.abstract
Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at ashs.org
It's not all bad for crow chicks who have to share their nest with an uninvited pushy guest such as a cuckoo youngster. For one, they can sit back and wait for food to arrive while the cuckoo chick does all the begging for nourishment. So says Diana Bolopo of the University of Valladolid in Spain, who led a study into the pros and cons associated with the parasitic relationship of the great spotted cuckoo with the carrion crow. The findings are published in Springer's journal Behavioral Ecology and Sociobiology.
When great spotted cuckoos parasitize and take over magpie ...
This news release is available in German.
Modern, machine-friendly agriculture is dominated by monocultures. One single cultivar - one genotype of a crop species - is cultivated on large areas. Favored cultivars are optimized for high yields and often contain only few natural plant defense compounds. Unfortunately, these extensive monocultures of identical plants can become an ecological wasteland and cause permanent damage to the ecosystem, especially when combined with blanket application of fertilizer and pesticides. Scientists at the Max Planck Institute ...
Researchers from North Carolina State University and the University of Colorado, Boulder, have developed a statistical model that allows them to tell where a dust sample came from within the continental United States based on the DNA of fungi found in the sample.
The primary goal of the research was to develop a new forensic biology tool for law enforcement or archaeologists. "But it may also give us a greater understanding of the invisible ecosystems of microbial life that we know are all around us, but that we don't fully comprehend," says Neal Grantham, a Ph.D. student ...
Adults who have ADHD are much more likely to report they were sexually and physically abused before they turned 16 than their peers without ADHD, according to a new study from researchers at the University of Toronto.
Among women, 34 per cent of those with ADHD reported they were sexually abused before they turned 18. In contrast, 14 per cent of women without ADHD reported that they had experienced childhood sexual abuse. Twice as many women with ADHD reported that they had experienced childhood physical abuse than women without this condition (44% vs 21%).
"These ...
A species of bone-eating worm that was believed to have evolved in conjunction with whales has been dated back to prehistoric times when it fed on the carcasses of giant marine reptiles.
Scientists at Plymouth University found that Osedax - popularised as the 'zombie worm' - originated at least 100 million years ago, and subsisted on the bones of prehistoric reptiles such as plesiosaurs and sea turtles.
Reporting in the Royal Society journal Biology Letters this month, the research team at Plymouth reveal how they found tell-tale traces of Osedax on plesiosaur fossils ...
UCLA researchers have found that 77 percent of California primary care and specialty physicians understand the basics of the Patient Protection and Affordable Care Act and 59 percent support it. The survey, conducted by doctors from the UCLA department of family medicine, was published in the peer-reviewed journal Family Medicine.
Researchers also found that a majority of the 525 doctors surveyed believe ACA will steer the country's health care in the right direction.
The doctors' stance on the law appeared to be closely correlated with their political affiliations ...
New research from New Zealand's University of Otago is providing the most comprehensive picture of the evolutionary history of baleen whales, which are not only the largest animals ever to live on earth, but also among the most unusual.
Most other mammals feed on plants or grab a single prey animal at a time, but baleen whales are famous for their gigantic mouths and their ability to gulp and filter an enormous volume of water and food.
In a paper appearing in the UK journal Royal Society Open Science, Otago Geology PhD graduate Dr Felix Marx and Professor Ewan Fordyce ...
New York, NY--April 15, 2015--A research team led by Shree K. Nayar, T.C. Chang Professor of Computer Science at Columbia Engineering, has invented a prototype video camera that is the first to be fully self-powered--it can produce an image each second, indefinitely, of a well-lit indoor scene. They designed a pixel that can not only measure incident light but also convert the incident light into electric power. The team is presenting its work at the International Conference on Computational Photography at Rice University in Houston, April 24 to 26.
"We are in the middle ...
UNIVERSITY OF CALIFORNIA, BERKELEY'S HAAS SCHOOL OF BUSINESS -CEOs make a lot of money from incentive pay tied to stock performance. Although such schemes help align executives' interests with shareholders, they are not necessarily the best schemes as compared to schemes that rely on trust between board and executives.
"Ironically, the necessary trust is easier to establish when the alternative of using stock-based pay is less powerful. Our research found that government-imposed limits on contingent compensation make stock-based pay a worse alternative, facilitating superior ...
Thermoluminescence is used extensively in archaeology and the earth sciences to date artefacts and rocks. When exposed to radiation quartz, a material found in nature, emits light proportional to the energy it absorbs. Replicating the very low dose of background radiation from natural sources present in quartz is a key precondition for precise and accurate dating results. Italian scientists have now developed a method to control the accuracy of the dose calibrations delivered to the samples during laboratory irradiation with heavy particles, replicating natural radiation ...
