I previously mentioned that I have little knowledge of the ocean as I grew up in the Prairies. My understanding of crop science and farming is, however, probably more extensive than the average person’s. Despite this, my grandparents only taught me about conventional farming.
Photo of my grandparent’s farm in Sturgeon County, Alberta. Photo from Samantha Kluthe
Organic farming is gaining more and more popularity with consumers. USA Today reports that the organic food sales hit $43 billion in 2016. It’s important to be aware of organic farming benefits with respect to our global energy crisis. I am interested in how organic farming differs to conventional methods in terms of energy consumption, and if it is a viable alternative in meeting the global food demand.
Whole Foods Market in Union Square. Whole Foods has a large influence in the organic food market. Photo from Aspersions.
I found a study on the energy efficiency of organic and conventional crop production with respect to two crop rotations. Researchers from the Universities of Manitoba and Saskatchewan discovered a significant interaction between rotation and management systems with respect to efficiency (output energy/input energy). Organic farming methods paired with integrated crop rotations are the most energy efficient. The energy input was 50% less in organic methods compared to conventional farming.
Crop rotation is the method by which farmers switch the type of crop they are growing on the same section of land every year. It seems counterintuitive to not always plant the crop with the highest selling price, but it leaves farmers with higher long-term yields. Although not as valuable, incorporating a legume-based field allows farmers to decrease their chemical fertilizer usage as nitrogen is naturally fixed. Weeds and insects are also discouraged as each new crop disrupts their life cycles and comes with its own biological variation.
The study took data from twelve years of farming with combinations of grain-based rotation and integrated rotation with conventional and organic styles of management. Grain-based rotations used wheat, peas and wheat flax (WPWF) as crops. Wheat alfalfa and alfalfa flax (WAAF) were the crops of the integrated rotation.
Figure 1. The total and output energy from 4 different farming styles. WPWF: Grain-based rotation, WAAF: Integrated rotation, C: conventional production, O: organic production. Data is from Hoeppner et. al (2006). Figure created by Elizabeth Porter.
Crop management and rotation style affect energy output independently. Figure 1 shows that integrated crop rotation produces a much larger output than grain-based. The alfalfa is able to fixate nitrogen, consequently suppressing weeds. The large difference in output energy is also because the crop types in WPWF and WAAF result in seeds and whole plants, respectively.
Figure 1 shows that the energy input is higher for conventional farming, regardless of crop rotation. This is because of the addition of fertilizer and pesticide to fields which increases fuel and machinery use.
The researchers concluded that organic farming is a much more energy efficient management system than conventional. It seems that it should be the direction that agriculture should step towards to prepare for the future energy crisis. However, the energy output is also higher for conventional style crops (Figure 1). It seems unlikely that organic farming will be able to keep food needs met, especially with the ever-rising global population.
From this, I am confident that scientists are headed in the right direction, but am still wary about spending 47% more on organic foods….
