Friday, January 7, 2011

A Brief Discussion of Agriculture Adaptation

The continuing increase of surface temperatures catalyzed by human driven climate change has lead some individuals to question the future of the current system of monoculture agriculture. When considering the weather related events of 2010, especially the heat wave in Russia, such questioning seems appropriate; however, it is also reasonable that individuals are overreacting to those events. One problem with the psychology of a number of individuals that correctly acknowledge human driven global warming is the incorrect association of all severe weather events with global warming.

Throughout history a number of extreme weather and other geological events occurred before any significant human driven global warming could have been an influencing element. Certainly in the future there will be a warmer environment with a higher probability of extreme or multiple standard deviation weather events due to global warming, but to attribute the occurrence of all extreme weather events as a result of global warming is inappropriate. The same can be said of assuming the entire collapse of the current annual monoculture agricultural system within the next decade simply because of one extreme heat wave event; such a mindset may in fact do more to damage the credibility of global warming than to push ‘on-the-fence’ individuals to action.

However, despite the inappropriate overreaction to the demise of the monoculture agricultural system, the future shift in climate will place more pressure on that system and if this pressure is not properly addressed then there will be significant problems. Sadly a number of individuals address these potential problems by suggesting a move away from monoculture to a more niche system without addressing why monoculture is used in the first place. To most that wish to replace monoculture it would be reasonable to suggest that their rationalities involve the belief that monoculture is used solely to increase profit margins for major agribusinesses and the general unsustainability of monoculture as currently practiced. While true, the profit margin increase is largely derived from an increase in planting and harvest efficiency. This efficiency allows for more effective scale-up, a greater production level and the capacity to feed more people.

Regardless of any sustainability issues the world population could never have climbed as high as it has without this particular method of agriculture. There is a debate to whether a more organic methodology can produce equivalent yields to a monoculture methodology on a single given plot of land, but there is no effective debate regarding whether a more organic methodology can match the total yield per input of monoculture on a replacement scale. Basically this debate breaks down to some arguing that organic or permiculture methods can produce the same average yield on 1 acre of land as monoculture, but no one is reasonably arguing that organic or permiculture can produce the same average yield on 10 acres of land as monoculture at similar cost.

That lack of large-scale efficiency from other methods is the looming problem for those wanting to replace monoculture with another methodology for as it currently stands such a replacement will either increase the total cost per yield or decrease the total yield with either result more than likely increasing food price. A decrease in yield will not only raise food price, but also reduce total food availability which would increase the number of malnourished or starving individuals in the world. This rarely mentioned by its supporters drawback to non-monoculture agriculture in addition to the total cost and effort required from switching from a high intensity monoculture methodology to a non-monoculture methodology should drive individuals to ask what can be done, if anything, to salvage the current system over simply scrapping it for something else.

So what are the real problems facing monoculture in the future? The number one problem will be continued access to ample supplies of water. Taking the United States as an example, in 2000 40% to 65% (depending on whether thermo-electric power is counted) of freshwater used the United States is directed towards irrigation as a theoretical necessity to supply enough food for the populous.1 This level of water use has not declined significantly since and no major environmental study attempting to discern global resource allotment signals that water supplies will increase in a beneficial and control manner. In a vast majority of regions either water supplies will decrease increasing the probability for more drought or water supplies will increase at a much faster rate than can be naturally controlled increasing the probability of flooding and crop damage. Neither result is useful for the general supply structure for any form of agriculture be it the current monoculture system or an alternative.

One reason such a large amount of water is required for irrigation is due to the annual nature of harvesting; most crops that are currently used in monoculture do not have the opportunity to establish deep root systems which disallows ‘reaching’ for natural deep water aquifers and reduces effective retention of human supplied water. However, once again that lack of a root system becomes a sticking point because if a methodology like permiculture is established in effort to facilitate the production of deeper root system to reduce both water and nitrate use, harvesting yields are reduced over the same amount of land used.

It stands to reason that there is a reasonable chance that after a sufficient period of time the conversion from monoculture to permiculture would result in similar yields, but again the period of time required for this transition and the total effective size ceiling is unclear. At present a better strategy to address water use than convert directly to a new agricultural methodology would be to change the current irrigation method. Most farmland currently uses either flood or spray irrigation1 which uses more water than drip irrigation in part because the more immature root system cannot process it all and in part because some water is inherently wasted through evaporation in effort to ensure enough for the entire crop; overall the only rational reason why flood irrigation is used over drip irrigation is cost, the significance of which lessens with every passing year.

Flood irrigation also causes a problem with run-off. The unutilized water typically collects nitrogen compounds as it runs off the edges of the farmland. If this run-off ends up in a larger river/stream it can be taken to a larger body of water where the nitrogen and other organic compounds facilitate algae growth leading to dead-zones. So regardless of what agriculture methodology is utilized, one of the most important steps in preparing for a warmer future is to change the irrigation technique most commonly used from flood or spray irrigation to drip irrigation. Some may argue that spray irrigation is the preferred irrigation technique, but the key issue is water conservation and drip irrigation uses less water on average than spray irrigation due to less evaporation and general water exposure.

Changing temperature patterns derived from climate change is the second most important issue in the evolution of agriculture systems. Most of the attention that is given to agriculture adaptation is derived from this element. Interestingly most of the adaptation measures suggested are quite high-tech and/or extreme such as genetically engineering heat and drought resistant strains. What is somewhat unknown is how many low-tech solutions have been proposed for addressing increases in average surface temperatures in high yield agriculture regions possibly because they are not ‘sexy’ enough to receive significant attention. For example something as simple as a tarp held aloft over crops should reduce the total negative influence of the increased temperatures. This tarp could also reduce heavy rain and wind exposure during growth and after harvesting which would aid yield quality and reduce after-harvest erosion probability respectively. Also due to the ‘grounding’ nature of ozone, a tarp may even offer some protection from increasing tropospheric ozone concentrations.

One low-tech solution could involve incorporating a drip irrigation system with a tarp at a declining angle of approximately 8-9 degrees (one side of the tarp elevated to 40 ft and the other elevated to 10 ft on a field with a length of 1 acre should do) could reduce temperatures, collect rain water and protect from heavy rain and wind exposure at nominal cost. Without an enclosed system the crops would receive some exposure from the x-axis on a given y-axis (slanted rain and winds originating below the height of the tarp), but the overall exposure should be significantly reduced. The one outstanding question with such a strategy would be ensuring that the crops received enough exposure to light; thus the tarp would have to be somewhat transparent and brief testing would have to be carried out to measure any significant drop-off in growth rate.

Some argue that future shortages in oil and gas will be significant problems. This contention is true only if society continues to depend on outdated methodologies. Based on supply structure, to be concerned about a dwindling supply of natural gas, which in an agriculture environment would be largely devoted to fertilizer production, seems alarmist. Some of the top food producing countries in the world, the United States, Canada and Russia all have ample supplies of natural gas that most experts content would last for centuries. Granted potential environmental problems stemming from fracking may slow exploration of new supplies, but if recent history is any indication industry is rarely stopped from doing what they want by environmentalists. Overall fertilizer production is much more likely to face a phosphate shortage (another possibility that drives more fear than it should) than a natural gas shortage, but neither is very likely in the near future.

A supply shortage of oil is much more real because oil prices have already begun climbing as the global economy comes out of the recession. In 2008 a rapid spike in oil prices, partially aided by speculation on futures, gave the world a brief glimpse of the future if oil continues to drive agriculture harvest and transport. The important element to note about 2008 is that most of the food riots in developing countries were not necessarily caused by a lack of absolute supply, but instead more by a lack of acquisition potential where food prices rose to a point out of reach of most individuals. One solution to the potential oil supply shortage and the projected corresponding increase in price would be the development of a solar powered combine and other harvesting machinery. Solar power would work well because of the high potency and availability of sunlight in the more crop heavy environments. The design of such equipment would not require any exotic technology or techniques because of similarities to solar power cars; these heavy farm implements would simply require more electricity due to the higher power demands.

The final major issue regarding agriculture is soil degradation. One of the chief arguments against annual monoculture is the progressive loss of high-quality topsoil due to various tilling techniques and empty field erosion. There are two significant elements in soil loss; first the loss of nitrogen compounds requiring the use of nitrogen-replenishing fertilizer and second the loss of the soil itself. Loss of the soil typically stems from erosion events which are most prominent immediately after a harvest in an annual monoculture system because of the ‘nakedness’ of the soil.

The most viable strategy to reduce the potency of these erosion events is to not remove all of the crops from the plot in the same harvest period. This is one point argued by most permiculture supporters when highlighting the benefits of permiculture. However, the problem with this solution is a significant loss of total yield, which reduces total available supply leading to price increases. Another possible solution to these loss of soil events would be to protect the soil after harvest by reducing exposure to water and wind elements. The above mentioned tarp cover idea would accomplish this goal and would probably reduce overall soil loss due to erosion.

Another strategy that is widely suggested to stem nitrogen compound loss in soil outside of fertilizer use is to rotationally plant nitrogen fixing crops like legumes in between normal crop rotations. This method has earned widespread acceptance and is frequently used in smaller organic plots. However, once again the question of scale and quantity rears its head as planting these legumes in fields that primarily run corn, wheat, soybeans, etc. reduce growing time for these crops. High-quality micromanagement with specific planting timetables can alleviate this problem by extending the growing season to accommodate both sets of crop rotations. However, it still remains to be seen how effective such a strategy would be in placement of large-scale annual monoculture farms. Fortunately a near-future nitrogen shortage seems unlikely, which gives farms time to introduce more natural nitrogen replenishment techniques. To those that believe farms will be hesitant to develop these techniques based on past experience one method of motivation may to be instill a small, but steadily increasing tax on fertilizer.

It is unfortunate when individuals decry current infrastructure and yet suggest a replacement that does not address the core problems of that current infrastructure, thus not actually solving the problem. This reality tends to be the result with individuals that proclaim their personal niche replacement to annual monoculture, focusing on the problem of monoculture and not effectively analyzing how their solution succeeds or fails to correct these problems and whether or not that solution creates its own problems.

The most important issue regarding the future of agriculture is the acknowledgement that barring a miracle food production will be done in a warmer world. Once that reality is accepted then effective analysis must be made regarding potential solutions. This analysis should first start by focusing on making changes that will address the four previously mentioned points from above with as little infrastructure change as possible to easy mass scale-up change. For those individuals that prefer a new agriculture methodology over annual monoculture, they need to show that not only can that replacement method replicate annual monoculture yields on small plots, but can also replicate annual monoculture yields over the whole system in addition to the future problems faced by annual monoculture.

1. United States Geological Survey Website. 2000.

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