Archive for the ‘Organic farming’ Category

Wisconsin study shows decisions on pasture use and feed management affect GHG emissions

American researchers have created a study to compare the effects of feeding strategies and the associated crop hectares on the greenhouse  gas emissions from certified organic dairy farms in Wisconsin.

According to a Science Daily report on the work (HERE) consumer demand for organic milk in the US recently surpassed the available supply. Sales of organic products reached US$35 billion in 2014 and continue to rise.

As farms convert  to organic production to meet demand, feeding strategies will need to be adapted to meet USDA National Organic Programme requirements.

Agriculture accounts for around 9% of total US greenhouse gas (GHG) emissions.

The US dairy industry has committed to a 25% reduction of GHG by 2020 relative to 2009. By varying diet formulation and the associated crop production to supply the diet, farmers can affect the quantity of GHG emissions of various feeding systems.

The study to compare the effects of feeding strategies and the associated crop hectares on GHG emissions of certified organic dairy farms was developed by researchers from the University of Wisconsin-Madison.

“Herd feeding strategies and grazing practices influence on-farm GHG emissions not only through crop production, but also by substantially changing the productivity of the herd,” lead author Di Liang said.

“Managing more land as pasture, and obtaining more of the herd feed requirements from pasture, can increase the GHG emissions if pasture and feed management are not optimised to maintain milk production potential.”

The authors identified four feeding strategies that typified those used on farms in Wisconsin, with varying degrees of grazing, land allocated for grazing, and diet supplementation. A 16-year study was used for robust estimates of the yield potential on organically managed crop land in southern Wisconsin as well as nitrous oxide and methane emissions and soil carbon.

Production of organic corn resulted in the greatest nitrous oxide emissions and represented about 8% of total GHG emission;. Corn also had the highest carbon dioxide emissions per hectare.

Emissions decreased as the proportion of soybeans in the diet increased, because soybeans require less nitrogen fertilization than corn grain.

More intensive grazing practices led to higher GHG emission per metric tonne. But  allowing cows more time on pasture resulted in lower emissions associated with cropland. Manure management and replacement heifers accounted for 26.3% and 20.1% of GHG emissions.

Based on their findings, the authors determined that a holistic approach to farm production is necessary. Organic dairy farms with well-managed grazing practices and adequate levels of concentrate in diet can both increase farm profitability and reduce GHG emission per kilogram of milk.

“Consumers often equate more dependence on pasture with environmentally friendly farming, but this study demonstrated that low milk production per cow is a major factor associated with high GHG emission,” said Journal of Dairy Science Editor-in-Chief Matt Lucy.

“Managing both pasture and supplementation to increase milk production per cow will substantially reduce GHG emissions.”

Factors such as dairy cow breed and non-production variables may also have an effect on GHG emissions on organic dairy farms. Thus, future studies are needed in this area to elucidate the effects of grazing management and feeding systems.

With more research, however, crop and milk production, GHG emissions, and farm profitability can be optimised on organic dairy farms.

 

Organic not the only ingredient in recipe for sustainable food production

A new UBC study published in Science Advances finds organic thinking alone is not necessarily better for humans and the planet.

Organic is often proposed a holy grail solution to current environmental and food scarcity problems, “but we found that the costs and benefits will vary heavily depending on the context,” said Verena Seufert, a researcher at the Institute for Resources, Environment and Sustainability (IRES).

Seufert and her co-author, Navin Ramankutty, Canada Research Chair in Global Environmental Change and Food Security at UBC, analysed organic crop farming across 17 criteria such as yield, impact on climate change, farmer livelihood and consumer health.

It is the first study to systematically review the scientific literature on the environmental and socioeconomic performance of organic farming, not only assessing where previous studies agree and disagree, but also identifying the conditions leading to good or bad performance of organic agriculture.

Two factors that are top of mind for many consumers are synthetic pesticide use and nutritional benefits of organic. Seufert and Ramankutty argue that in countries like Canada where pesticide regulations are stringent and diets are rich in micronutrients, the health benefits of choosing organic may be marginal.

“But in a developing country where pesticide use is not carefully regulated and people are micronutrient deficient, we think that the benefits for consumer and farm worker health may be much higher,” said Ramankutty, professor at IRES and the Liu Institute for Global Issues at UBC.

Another important measure of the sustainability of farming systems is the yield of a crop. To date, most studies have compared the costs and benefits of organic and conventional farms of the same size, which does not account for differences in yield.

Previous research has shown the yield of an organic crop on average is 19 to 25 per cent lower than under conventional management. Seufert and Ramankutty find that many of the environmental benefits of organic agriculture diminish once lower yields are accounted for.

“While an organic farm may be better for things like biodiversity, farmers will need more land to grow the same amount of food,” said Seufert. “And land conversion for agriculture is the leading contributor to habitat loss and climate change.”

The findings suggest that organic alone cannot create a sustainable food future. The authors nevertheless conclude it still has an important role to play. Buying organic is one way that consumers have control over and knowledge of how their food is produced since it is the only farming system regulated in law.

“We need to stop thinking of organic and conventional agriculture as two ends of the spectrum,” said Seufert.

Instead, consumers should demand better practices for both so the world’s food needs can be met in a sustainable way.

Study of 74,000 bottles looks into whether organic wines taste better

Britain’s Daily Telegraph says a new study of wines shows it really is worth going natural.

The researchers from the University of California trawled through the expert reviews for more than 74,000 wines which appeared in the three of the world’s best wine-rating magazines, the newspaper reports.

They discovered that organic wines – which are labelled as ‘ecocertified’ in the US – scored an average of 4.1 points higher than their non-organic counterparts, our of a score of 100.

The academics speculate that adopting organic practices and banishing pesticides allows microbes in the soil to flourish, which enhances the flavour of grapes and give a truer representation of the ‘terroir’ or the natural environment of the vine.

Growing grapes without fertilisers also reduces yield, which may improve quality because the vine needs to ripen a smaller amount of fruit, and so the juice becomes more concentrated, and tastier.

To determine the quality of organic versus non-organic wines, the team studied 74,148 wines from California, which were of vintages between 1998 and 2004, from 3,482 vineyards.

They examined reviews from three respected publications; the Wine Advocate, Wine Enthusiast and Wine Spectator.

The study looked at more than 30 grape varieties including Cabernet Sauvignon, Chenin Blanc, Merlot, Pinot Noir, Sangiovese, Semillon and Zinfandel.

The Daily Telegraph headline says “Study of 74,000 bottles shows organic wine really does taste better”.

The study and the title of the report – “Does Organic Wine Taste Better? An Analysis of Experts’ Ratings” – are somewhat less emphatic.

The abstract says:

Our results indicate that ecocertification is associated with a statistically significant increase in wine quality rating. Being ecocertified increases the scaled score of the wine by 4.1 points on average.

The researchers acknowledges their study “is not without limitations”.

First, they focused on the California wine industry. Perceptions about ecocertification may vary according to the institutional context in which they are implemented and the specific standards of ecocertification.

Second, although they were able to gather a comprehensive database of wine ratings from the major wine experts, there is still some uncertainty about the evaluation process and how much the wine experts actually know about the wine before tasting it. Further research involving blind wine tasting to better isolate the effect of organic certification is suggested.

Third, because of the limited number of ecocertified wines, the researchers classified all types of ecocertified wines together. There might be quality differences among the three different types they did not account for, and future research could investigate such differences.

The Daily Telegraph quotes lead author Professor Magali Delmas, of the UCLA Institute of the Environment.

She said there is littler consensus as to whether ecocertified (or organic) wines are associated with worse, similar or better quality than their traditional counterparts.

“Our results indicated that the adoption of wine ecocertification has a significant and positive effect on wine ratings.

“The results are interesting because they contradict a general sentiment that ecolabeled wines are of lower quality.”

Susy Atkins, the wine columnist for the Sunday Telegraph’s Stella magazine said drinkers should consider looking out for the organic label.

“There will always be good and bad organic wines, but generally it implies good use of the land and a viticulturist who really cares about their vines,” she said.

“The problem can be that it often pushes the price up because organic growing is quite labour intensive.

“But it is very good for the land. You visit an organic vineyard and there are insects flying around, and birds singing and it feels like an entirely different experience.”

Several recent reviews suggest organic food is neither tastier nor more nutritious than traditionally farmed produce.

In 2012 Stanford University’s Centre for Health Policy did the biggest comparison of organic and conventional foods and found no robust evidence for organics being healthier.

A follow-up review by The Norwegian Scientific Committee for Food Safety similarly reported that organic food was not more nutritious.

New study finds clear differences between organic and non-organic milk and meat

Organic milk and meat contain around 50% more beneficial omega-3 fatty acids than conventionally produced products, new research has shown.

Key findings are set out in a press release from Newcastle University.

• both organic milk and meat contain around 50% more beneficial omega-3 fatty acids than conventionally produced products

• organic meat had slightly lower concentrations of two saturated fats (myristic and palmitic acid) that are linked to an increased risk of cardiovascular disease

• organic milk contains 40% more conjugated linoleic acid (CLA)

• organic milk contains slightly higher concentrations of iron, Vitamin E and some carotenoids

• conventional milk contained 74% more of the essential mineral iodine and slightly more selenium

An international team of experts led by Newcastle University, in the United Kingdom, reviewed 196 papers on milk and 67 papers on meat.

It found clear differences between organic and conventional milk and meat, especially in terms of fatty acid composition, and the concentrations of certain essential minerals and antioxidants.

Publishing its findings in the British Journal of Nutrition, the team say the data show a switch to organic meat and milk would go some way towards increasing our intake of nutritionally important fatty acids.

The study showed that the more desirable fat profiles in organic milk were closely linked to outdoor grazing and low concentrate feeding in dairy diets, as prescribed by organic farming standards.

The two new systematic literature reviews also describe recently published results from several mother and child cohort studies linking organic milk, dairy product and vegetable consumption to a reduced risk of certain diseases. This included reduced risks of eczema and hypospadias in babies and pre-eclampsia in mothers.

The press release relates to two papers published in the same journal on the same day –

  • “Higher PUFA and omega-3 PUFA, CLA, a-tocopherol and iron, but lower iodine and selenium concentrations in organic bovine milk: A systematic literature review and meta- and redundancy analysis”. Carlo Leifert et al. British Journal of Nutrition
  • “Composition differences between organic and conventional meat; a systematic literature review and meta-analysis”. Carlo Leifert et al. British Journal of Nutrition.

Researchers to see if oregano can reduce methane in cow burps

Researchers from Aarhus University in cooperation with Organic Denmark and a number of commercial partners will be examining whether the addition of organic oregano to cattle feed can reduce the production of methane in the rumen and thus emissions of methane gas.

They hope to show that methane emissions from dairy cows can be reduced by up to 25 per cent by adding oregano to the feed.

Oregano – especially the species Greek oregano (Origanum vulgare ssp hirtum) – is known for its high content of essential oils and its antimicrobial effect. The plant is a natural tool for reducing methane production in the rumen, says project manager and Senior Researcher at the Department of Food Science, Kai Grevsen.

Researchers initially will test the effect of supplementing with oregano on rumen- and intestinal-fistulated dairy cows in special methane chambers. They will also examine how the cows react to different amounts of oregano. The feeding with oregano will then be tested in practice on a number of organic dairy farms producing milk for ‘Naturmælk’ (organic dairy).

The four-year project moreover will investigate how best to grow organic oregano and whether to process the plant either as hay or silage.

To succeed with the oregano project in practice, it is essential to develop  a product that has both a high yield and a high concentration of essential oils, Grevsen says.

Developing an organic farming concept and breeding new varieties with higher concentrations of the oils, will be necessary too.

The climate will be the main beneficiary of the project if it is successful. But the researchers hope the project will also benefit arable and dairy farmers.

Previous studies indicate that oregano can improve the milk’s fatty acid composition, and the project participants will therefore be researching this aspect as well as the milk’s flavour.

Another hope is that the research will pave the way for a number of new products that can be sold on the basis of their climate-friendliness, targeting environmentally conscious consumers.

“We know that the market for dairy products is characterised by an increasing willingness to pay more for milk with special qualities or values, especially organic, and we hope that in the project we will have a good and balanced dialogue with consumers about the climate and cattle production,” says Grevsen.

“It’s also important to remember that the project is relevant not only for organic milk producers. Should the results be positive, they can be implemented on all cattle farms, conventional and organic, so there is a really large potential.”

The project is financially supported by the Green Development and Demonstration Programme under the Ministry of Environment and Food of Denmark and by the cattle and milk levy funds.

Project partners are the departments of Food Science and Animal Science at Aarhus University, Organic Denmark, Naturmælk, dairy farmers Frode Lehmann, Günther Lorenzen and Laust Stenger, and the commercial growers Urtefarm and Sunny.

The project is led by Senior Researcher Kai Grevsen from the Department of Food Science in collaboration with Senior Researcher Peter Lund from the Department of Animal Science, both from Aarhus University, and by Else Torp Christensen from Organic Denmark.

 

 

Major study documents nutritional and food safety benefits of organic farming

The largest study of its kind has found that organic foods and crops have a suite of advantages over their conventional counterparts.

The benefits include more antioxidants and fewer, less frequent pesticide residues, according to a media release from Washington State University.

The study looked at 343 peer-reviewed publications comparing the nutritional quality and safety of organic and conventional plant-based foods, including fruits, vegetables and grains.

The study team applied sophisticated meta-analysis techniques to quantify differences between organic and non-organic foods.

Continue reading

Organic agriculture is found to pollute groundwater

Researchers from Ben-Gurion University of the Negev (BGU), using specialised monitoring technology, have determined that intensive organic agriculture can cause significant pollution from nitrate leaching into groundwater.

Information provided by American Associates, Ben-Gurion University of the Negev, says public demand has led to the rapid development of organic farming in recent years to provide healthy food products that are free of chemical additives and to reduce industrial and groundwater pollution worldwide.

But according to the paper published in the Hydrology and Earth System Sciences journal, intensive organic matter using composted manure prior to planting resulted in significantly higher groundwater pollution rates compared with liquid fertilisation techniques through drip irrigation.

Continue reading