Back to basics - Organic Farming

As we have seen, the modernization of agriculture has come with many environmental implications in the quest to feed our growing population throughout the anthropocene. Many argue that we should revert back to old-fashioned agricultural practices to reduce the environmental damage. This would involve a change from intensive monoculture systems, which are heavily reliant on inputs of natural resources, to smaller scale organic agriculture with less external inputs to supply local demands, using more natural forms of energy inputs.

         In organic agriculture, chemical fertilizers and pesticides are not used. Complex crop rotations are used to protect against pests and animal manure is used as a natural fertilizer, legumes are planted to fix nitrogen rather than using chemical fertilizers. The Soil Association state ‘Organic farming offers the best, currently available, practical model for addressing climate-friendly food production. This is because it sequesters higher levels of carbon in the soil, is less dependent on oil-based fertilisers and pesticides and confers resilience in the face of climatic extremes.’

Pimentel et al (2005) report on a Rodale Institute farming trial, which compared organic and conventional farming over 22 years. The main conclusions from the trial reveal that:

–           Fossil fuel energy inputs were 30% lower in organic practices.

–           Soil organic matter was higher in organic systems, this helped conserve soil and water resources, which were beneficial in drought years, this is important for the future with climate change.

–           Nitrogen was higher in organic systems which highlights the success of legume cover crops over chemical fertlisers.

–           Crop rotations and over cropping successfully reduced soil erosion, pest problems and pesticide use in organic practices.

–           Use of livestock waste as fertilizer reduced pollution as well as the use of chemicals.

–           Organic plots had higher biodiversity, which contributes to a healthy ecosystem and reduces the need for chemical fertilizers and pesticides.

         Through the successes seen in the organic plots throughout the study, Pimentel et al (2005) suggest that in order to make our food production more sustainable we should incorporate some organic practices into our conventional systems.

         Organic agriculture wont stop our reliance on natural resources but it is using them in a more sustainable way. Organic farming technology can help make farming more sustainable and ecologically sound, but it is heavily debated whether organic agriculture can produce high enough yields at affordable prices to feed the world.

Can Genetic Modification Save the World?

            Genetic modification (GM) is often marketed as the solution to our global food crisis. GM crops are sold on the basis of their economic and environmental benefits through increasing yields and greater food production with lower production costs, compared with conventional crops.

            A Royal Society report ‘Reaping the Benefits’ (2009), supports the use of GM crops. The report confirms that GM can provide control of pests and weeds through use of disease-resistant crops that can minimize the use of chemical pesticides and herbicides. They also suggest that GM crops enable no-till agriculture, which can reduce soil erosion and fossil fuel use and drought tolerant seeds can be used to provide resilience to climate change. Thus the report states that ‘Britain's future food sustainability depends on employing some form of GM to increase yields’.

            The Royal Society fully support the notion that technological advances have provided us with the potential to use scientific solutions to feed the world. The report indicates that the problem of food security for our growing population is so serious that we should try anything we can, to solve the problem, and that this will not be possible without the use of GM.

            Alternatively, a group of NGOs, coordinated by environmentalist Vandana Shiva, produced a report on the role of genetically modified organisms (GMO) in increasing food production (Global Citizens' Report on the State of GMOs, 2011). The report reveals that the way that genetic modification is marketed as the solution to the world’s food crisis is highly misleading. Shiva boldly states that genetic engineering has failed to increase the yields of a single food crop but instead, it has increased the growth of superweeds.

            The NGO report indicates that weeds are becoming resistance to herbicides and pesticides, through the transfer of herbicide resistance to weeds, resulting in the development of super weeds and super pests. Shiva (2011) gives examples of this in India, China, the US, Argentina and Brazil and describes it as failed technology, as GM crops have not increased the control of pests and weeds, they have actually reduced it. This has resulted in an increase in the requirement of pesticides.

            Evidence suggests that some GM crops actually have reduced yields when herbicides are not applied therefore GM crops can increase our reliance on herbicides. Some believe, that the biotech industry is forcing us into a more chemical dependent agricultural system. Shiva (2011)  states that any benefits of GM crops are outweighed by the negative impacts associated with increased use of pesticides.

            These two reports from different reputable actors puts great uncertainty in the fate of GM crops as a solution to sustainable food production for the future. For some, it seems like the ideal solution for increased yields and resistance to pests and weeds, whereas others see the problems of the uncertainty associated with the use of new technology and ideas. As the Global Citizens' Report on the State of GMOs reveals, technology and nature do not always interact as expected and as a result, GM crops could create a food production system ever more reliant on natural resources. 

            Whether we go ahead with GM food production or not is a highly important decision, as co-existence between GM and conventional crops is not possible due to genetic pollution and contamination of conventional crops which is impossible to control (Shiva, 2011). Therefore the Royal society report admits that we need a lot more investment in research into sustainable agriculture before we go ahead and fully implement GM practices. 

This is a obviously a very brief overview of the debates associated with Genetic Modification, so check out the two reports in more detail if you're interested.

I quite like this cartoon I found on another blog.

Modern Agriculture: The Cause? Or the Solution?

This video clearly states that technology has a large role to play in the solution and that old fashioned methods wont produce enough to feed the world. However, I am skeptical, as technology has not helped to reduce the environmental impact so far, it has in fact worsened it. Therefore I don't see how this simplistic video can state that 'with careful stewardship of the earth' modern agriculture is the solution.... its just not that simple! However, it does nicely highlight the issues associated with government policy and how these need to change in order to produce enough food sustainably. 

Global food systems must be transformed ‘on industrial revolution scale’

The existing food production system clearly isn’t working as millions of people are still malnourished and the environmental impact of food production is not sustainable – as this blog has shown.

‘1 billion are going hungry, 1 billion are lacking crucial vitamins and minerals from their diet and another billion are "substantially overconsuming”’ (Guardian, 2011).

This Guardian article 2011 highlights the need for a change in agricultural practices as shown in the Global Food and Farming Futures report, from the Government office for science. The article nicely sums up how, with our current practices, the world cannot feed itself without destroying the environment, therefore we have no option but to make a change.

We have three main issues – an expanding population to feed, which requires  a change in the unsustainable nature of the exploitation of our natural resources as well as consideration for the impacts associated with climate change – as agriculture is a large contributor of green house gasses. These issues highlight the urgency of the problem.

            The main conclusion is that farmers need to grow more food at a smaller cost to the environment – but unfortunately this is easier said than done and as a result, the report comes to the conclusion that no single solution exists.

            The report states that the solution must involve reducing food waste and spreading our existing knowledge to developing countries. As well as the incorporation of organic agriculture, although the report states that this shouldn’t be the main strategy, as they don’t believe that organic agriculture can meet future demands without huge changes in peoples diets (I will address this in a later post). The report also states that technological advances should be considered such as genetically modified crops and cloned livestock and that they shouldn’t be excluded on ethical or moral grounds. They also highlight that government policy has a large role to play in changing global food systems as the government have been criticized for suggesting that technology holds the solution, many believe it will take a lot more than that!

Have a read of the Guardian article and let me know what you think… should we put our faith in technology and go for GM or should we go back to the small scale organic production of the past, after all, it was a technological revolution that got us into this mess in the first place. Can technology get us out of it again?

Why are we using up our natural resources feeding livestock?

A 2006 United Nations, Food and Agricultural Organization report has brought to light many of the problems associated with the production of meat. Increased wealth has lead to changes in food preferences, which has resulted in increased consumption of meat. During the past 40 years global per capita meat production has increased more than 60% (Tilman et al 2002). Livestock products now provide one third of humanity’s protein intake and global production of meat is projected to more than double from 1999 to 2050 with our growing population (UN, 2006). The report states that the livestock sector emerges as one of the most significant contributors to the most serious environmental problems, on a local and global scale. The meat industry contributes heavily to problems of land degradation, climate change, air pollution, water shortage and pollution and loss of biodiversity.

5 reasons why you should become a vegetarian!         

• The livestock sector is responsible for 18% of greenhouse gas emissions measured in CO2 equivalent (this is a higher share than transport). The largest share of this comes from land use change, especially deforestation (UN 2006).
• Overgrazing by cattle for meat degrades land and reduces soil productivity. Livestock production accounts for 70% of all agricultural land and 30% of the land surface of the planet. This includes the vast amount of land required to grow feedcrops for cattle which has resulted in huge amounts of deforestation (UN 2006).
• The livestock sector accounts for over 8% of human water use, mostly for the irrigation of feedcrops (UN 2006).
• The production of 1kg of meat requires between 3 and 10kg of grain, which requires vast amounts of land and many natural resources for growth (Tillman et al 2002). Therefore for the same input of resources you get a much smaller output compared to eating the grain directly, making the system less efficient.
• Meat eating adds a trophic level to the food chain and energy is lost with each trophic level, meaning that meat eating is less energy efficient than vegetarianism. Therefore meat eating increases depletion of earths natural resources (Tillman et al 2002).

Therefore increased meat consumption is not helping in the quest to feed the world’s growing population within the world’s environmental limits. 

Coastal Eutrophication – The impact of Agriculture in Chesapeake Bay

Over the past 300 years, Chesapeake estuary in mid-Atlantic USA has been converted from natural forests and wetlands into agricultural fields and urban development. Brush (2009) took sediment cores from the estuary, dating back 14,000 years ago, to look at the effects of these changes.

Sediment, nitrogen, pollen, diatom, and seed profiles from sediment cores suggest that prior to disturbance, the nitrogen cycle of this area consisted of a balance between biological nitrogen fixation and denitrification (Brush, 2009). This balance was maintained while small agricultural settlements were developed. However as land use changed to incorporate more intensive farming to support a growing population, this balance was disturbed. As agriculture grew and became more intensive, wetlands were drained, land was deforested and streams were channelized to reduce flooding of agricultural land and chemically produced nitrogen fertilizers were used to farm less fertile, marginal land. Changes to the landscape vegetation, hydrology and geochemistry resulted in a reduced denitrifying capacity of the area. This resulted in increased nitrogen loadings into the estuary, which lead to coastal eutrophication.

This diagram was produced to highlight the changes in the area over time. It is evident that many changes occurred as the population increased and with the onset of intensive agriculture (Brush, 2009).

The diagram shows how pollen types reflect the changes in land use. Sedimentation rates also increase as land was cleared for agriculture. These changes led to a shift from a benthic dominated system to planktonic dominated system, due to lack of light in the water column, which was further reduced by continued Planktonic algal growth. The increase in fertilizer purchases was mirrored by nitrogen fluxes in the sediment column. Through the process of eutrophication, this eventually led to the deep waters becoming anoxic and productivity declined (Brush, 2009).

Brush (2009) highlights how coastal eutrophication in Chesapeake Bay has significantly reduced coastal shellfish and fishery resources (especially oyster farming as shown in the diagram), which are important food sources for humans. Therefore in an attempt to feed the growing population of Chesapeake Bay through intensive agriculture, other valuable natural food resources were destroyed, and so far, all efforts to return Chesapeake Bay to its natural state have failed.

Ecosystem services as natural resources

Defra defines ecosystem services as ‘what nature gives us - Nature provides us with the very essentials of life. It gives us clean air and water; enables us to produce and gather food, fuel and raw materials from the land and sea; regulates our climate; stems flood waters and it filters pollution’. Ecosystem services provide us with natural resources. However, intensive agriculture can put many of these at risk (Tilman et al., 2002).

SOIL - plays vital roles in biogeochemical cycles and the water cycle. They provide nutrients, which enables plant growth and they play a part in flood control, and water filtration among many other processes. ‘Since 1945 approximately 17% of vegetated land has undergone human-induced soil degradation and loss of productivity’ (Tilman et al., 2002). Monocultures and continuous cropping remove nutrients from the soils and reduce soil organic matter, which reduces the stability and fertility of the soil. The reduction of this ecosystem service then results in larger fertilizer and irrigation requirements.

FORESTS- ecosystem services include - minimizing flooding, moderating regional climate, removing atmospheric carbon dioxide and aiding regeneration of fertile soils (Tilman et al., 2002). Greater food demands has led to deforestation to increase land available for agriculture. With continued population growth this will continue, with most deforestation in developing countries, which will have a major impact on the extent of tropical forests and the ecosystem services they provide (Eickhout et al 2006).

BIODIVERSITY – is vital to the maintenance of all ecosystem services. One of the main services provided by biodiversity is disease and pest resistance (Tilman et al., 2002). As previously explained, monocultures remove these protective ecosystem services. Pesticides are therefore used to reduce this problem. However, they have many adverse affects. Rachel Carson’s book silent spring explains the problems associated with increased use of chemical pesticides including the problems associated with non target species ingesting pesticides. Especially the toxic side effects of organochloride insecticides (DDT), which fueled the green revolution. The high persistence of DDT means it moves up the food chain causing more severe effects at successive trophic levels (Krebs et al. 1999). Pesticides can therefore lead to reduction of biodiversity by affecting non-target species and therefore further reduction in ecosystem services. Pollination and seed dispersal by insects and birds are vital ecosystem services that are vulnerable to destruction due to the use of pesticides. These losses would have direct adverse affects to agriculture.

FRESHWATER – has many obvious ecosystem services including water for human consumption, irrigation, power and transport. However, the use of fertilizers and pesticides in agriculture jeopardizes these ecosystem services by causing eutrophication (Eickhout et al., 2006). As shown in this very simplistic but informative video…

In turn eutrophication will reduce the availability of freshwater and the ecosystem services it provides for agriculture.

It is clear that maintaining ecosystem services is crucial for sustainable agricultural production and this is vital if we are to meet the demands of food production in the future. Some ecosystem services such as pollination or control of pests are of direct benefit to the farmer but others may be beneficial to people in general, therefore less care is taken over their preservation. Tilman et al. (2002) state that ‘Agriculturalists are the principle managers of global ‘usable’ lands’. This highlights the great control farmers have over our ecosystem services and therefore our natural resources.