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Archive | July, 2014

Soil Fertility: 16 Methods to Understand

soil organisms cultivate the soil

In nature, organisms cultivate the soil.

Soil fertility and sustainable agriculture practitioners know that most soils today need their health and vitality rebuilt. In times past, nature built healthy, vital soils, and there is value in copying nature in rebuilding soil health. However, we cannot afford to take millions of years to do so as nature did — we need intelligent intervention. Cultivation, grazing, composting, soil conservation, green manuring, soil testing, soil remineralization, fertilizer priorities, fossil humates, and visual soil assessment all play a role in establishing self-regenerative, self-sufficient, fertile soils.

The biological activities at the basis of self-regenerative soil fertility occur at the surfaces of soil particles where minerals come into contact with water, air, and warmth. It is at these surfaces that biological activities provide nitrogen fixation and silicon release. Continue Reading →

Avoiding Sunlight May Backfire

Avoiding Sunlight May BackfireExposure to ultraviolet (UV) radiation from sunlight is often cited as a cause of skin melanomas; however, research from Sweden suggests that low vitamin D levels caused by avoiding sunlight may be just as dangerous. The research, published in the Journal of Internal Medicine, found that women who avoid sun exposure are at an increased risk of skin melanomas, with a two-fold increased mortality rate compared to those with the highest sun exposures. The finding is the result of a longitudinal cohort study involving 29,518 Swedish women over 20 years.

This article appears in the July 2014 issue of Acres U.S.A.

Healing the Soil with Organic Methods

Healing Soil With Organic MethodsRodale Institute has launched a global campaign to generate public awareness of soil’s ability to reverse climate change, but only when the health of the soil is maintained through organic regenerative agriculture. The campaign calls for the restructuring of our global food system with the goal of reversing climate change through photosynthesis and biology. The white paper, “Regenerative Organic Agriculture and Climate Change: A Down-to-Earth Solution to Global Warming,” is the central tool of the campaign. If management of all current cropland shifted to reflect the regenerative model as practiced at the research sites included in the white paper, more than 40 percent of annual emissions could potentially be captured. If, at the same time, all global pasture was managed to a regenerative model, an additional 71 percent could be sequestered.

This article appears in the July 2014 issue of Acres U.S.A.

Mitigating Nitrogen Pollution with Eco-Farming

Fighting Nitrogen PollutionChemical compounds containing reactive nitrogen are major drivers of air and water pollution worldwide, and hence of diseases like asthma or cancer. If no action is taken, nitrogen pollution could rise by 20 percent by 2050 in a middle-of-the-road scenario, according to a study published by scientists of the Potsdam Institute for Climate Impact Research. Ambitious mitigation efforts, however, could decrease the pollution by 50 percent. The analysis is the very first to quantify this. “Nitrogen is an irreplaceable nutrient and a true life-saver as it helps agriculture to feed a growing world population — but it is unfortunately also a dangerous pollutant,” says Benjamin Bodirsky, lead-author of the study. In the different forms it can take through chemical reactions, it massively contributes to respirable dust, leads to the formation of aggressive ground-level ozone and destabilizes water ecosystems.

This article appears in the July 2014 issue of Acres U.S.A.

Gut Microbiota Linked to Autism

autism-spectrum-disorderChildren with autism spectrum disorders (ASD) have significantly different concentrations of certain bacterial-produced chemicals, called metabolites, in their feces compared to children without ASD. “Most gut bacteria are beneficial, aiding food digestion, producing vitamins, and protecting against harmful bacteria. If left unchecked, however, harmful bacteria can excrete dangerous metabolites or disturb a balance in metabolites that can affect the gut and the rest of the body, including the brain,” said Dae-Wook Kang of the Biodesign Institute of Arizona State University. Increasing evidence suggests that children with ASD have altered gut bacteria. In order to identify possible microbial metabolites associated with ASD, Kang and his colleagues looked for and compared the compounds in fecal samples from children with and without ASD. They found that children with ASD had significantly different concentrations of seven of the 50 compounds they identified.

This article appears in the July 2014 issue of Acres U.S.A.

Crop Nutrients Fall as CO2 Rises

greenhouse-growingAt the elevated levels of atmospheric CO2 anticipated by around 2050, crops that provide a large share of the global population with most of their dietary zinc and iron will have significantly reduced concentrations of those nutrients, according to a new study led by the Harvard School of Public Health published in Nature. Given that an estimated 2 billion people suffer from zinc and iron deficiencies, the reduction in these nutrients represents the most significant health threat ever shown to be associated with climate change.

Some previous studies of crops grown in greenhouses and chambers at elevated levels of CO2 revealed nutrient reductions, but those studies were criticized for using artificial growing conditions. Experiments using free air carbon dioxide enrichment (FACE) technology became the gold standard as FACE allows plants to be grown in open fields at elevated levels of CO2, but those prior studies had small sample sizes and have been inconclusive.

Researchers analyzed data involving 41 cultivars (genotypes) of grains and legumes from the C3 and C4 functional groups (plants that use C3 and C4 carbon fixation) from seven different FACE locations in Japan, Australia and the United States. The level of CO2 across all seven sites was in the range of 546-586 parts per million (ppm). They tested the nutrient concentrations of the edible portions of wheat and rice (C3 grains), maize and sorghum (C4 grains) and soybeans and field peas (C3 legumes).

The results showed a significant decrease in the concentrations of zinc, iron and protein in C3 grains. For example, zinc, iron and protein concentrations in wheat grains grown at the FACE sites were reduced by 9.3 percent, 5.1 percent and 6.3 percent respectively, compared with wheat grown at ambient CO2. Zinc and iron were also significantly reduced in legumes; protein was not.

This article appears in the July 2014 issue of Acres U.S.A.