Wicking bed – a new technology for adapting to climate change

 

The Copenhagen conference has shown the difficulties of reaching international agreement on climate change.  The political and technical obstacles are discussed in ‘climate change – obstacles to agreement’.

This shows that it is virtually impossible to cut emission on a global basis.  Even if it were possible to cut emission it does not solve the problem of global warming. The emissions are still there and accumulating. We need the technology of removing carbon from the atmosphere.

We are already suffering from damage to our soils making food production more uncertain. Erratic rainfall resulting from climate change will make food production even more difficult.. This is discussed in ‘food production and climate change’

 We need a new approach, with new technologies, which will lead to a sustainable but still affluent society.

 We are focusing too hard on reducing emission and ignoring the obvious alternative solution to climate change.  Plants already absorb 30 times all man made emission.  See plants absorbing carbon.  Yet the carbon that is absorbed is rapidly returned to the atmosphere.  By changing our agricultural system, for example by adopting the wicking bed technology, we capture carbon which is locked in the soil and make food production better able to cope with more erratic rainfall.

Changing our agricultural system so it becomes a net absorber of carbon, which is captured in the soil, is essential if we are to manage climate change and have stable food production

These two aspects of absorbing carbon and stabilizing food production are totally entwined, they cannot be separated.

This document aims to provide information to our political leaders on how to mitigate climate change and adapt our food production to the more erratic rainfall.


 

Climate change – obstacles to agreement

 

Copenhagen shows the great difficulty in reducing carbon emissions.

In the developed countries there appears be widespread support for reducing emission but the practical problems are immense.  A modern city is very different to the traditional village where food and most supplies are obtained locally. We have an entire infrastructure, city layout and technology based on readily available energy and transport.

Energy demand can be reduced by improving efficiency. Introducing non fossil energy sources such as solar and wind power will further help, but not on the scale required to achieve the cuts necessary.

The situation in the so called developing countries is even more difficult.  These countries do not comprise a homogeneously poor population. This is why I prefer to call them hybrid societies.  China for example leads the world in certain areas of technology, has a significant affluent middle class population - bigger than most other countries and yet has a large population who operate in a peasant economy with a low standard of living.

 China has of course long moved out of the ranks of the so called developing countries, but look at a country like Ethiopia which has a public image of being a very poor country.  It is true there are many people living in a state of poverty but there is also a significant middle class with many local owned and run manufacturing companies. They have either gained their skills by working in multi-national companies or by western companies offering a package of machinery, training and sometimes capital (or at least deferred payment).

 These countries comprise a privileged minority - who enjoy a standard of affluence not unlike the developed countries - and a majority who are at the subsistence level. These poorer people are struggling to achieve the affluence of their richer cousins.  Modern information technology is ubiquitous in even the most remote corners of the world.  The poor are informed of their poverty. In practice this creates a pressure which is impossible to resist. It would also be highly unethical.

We just have to accept that emissions from these hybrid or developing countries are going to continue to grow as more people enter the ranks of the more affluent class. The developed countries simply cannot cut back their emission sufficiently to compensate for the growth of emissions in the hybrid (developing countries).

This article is not meant to be a comment on political systems, only to discuss the obstacles to adoption of a global agreement.  For legislation to be passed in countries such as Australia and the US it has to pass through two levels, for example in Australia the house of representatives which is controlled by the Government of the day and the Senate, which is a house of review and can be controlled by the opposition.

In both Australia and America the opposition takes a short term economic position saying that legislation should not be passed if this results in the local industry being disadvantaged in comparison with the hybrid (so called developing countries) who have not as yet passed legislation to curb emissions

As these countries, particularly China, are so rapidly expanding it is virtually impossible for them to cut their absolute level of emissions.  China’s position that it will reduce emission per unit of gross national product is the only the practical option for them.

However if the opposition parties in Australian and the US feel that this is still disadvantaging the local industry they can block legislation, even though the Government of the day is trying to pass legislation.

This is a major hurdle which will not be overcome easily. 

 

 

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Food production and climate change

 

 

The world’s population grows exponentially but despite many people fears there has been no overall food shortage.  Far from being in short supply there is an overall abundance of food and the amount of food wasted runs into billions of dollars each year. Food production has continued to outpace population basically because of wider use of fertilizers, better genetics and plant breeding and the wider use of irrigation.

Despite the short term success they lead to long term degradation of our ecological resources, particularly the destruction of soil structure.

Many people, like me, have been concerned that these agricultural systems are unsustainable in the long term and have worked to develop food production systems which are genuinely sustainable.

In the long term these sustainable practices, largely based on building up soil quality, can be economic but in the short term there is a financial cost.  Typically growers are under great price pressure and cannot afford this short term cost of change.  The result is that unfortunately these sustainable techniques have only been adopted by ecologically sensitive growers with financial resources. 

 The wicking bed system stores significantly quantities of water and reduces water use, in some cases by up to 50%.  This reduces the frequencies of irrigations and in the case of rain fed crops increases the length of productive growth after a rain.

The moist conditions inside a wicking bed are conductive to the growth of mycelium (the network of long hyphae which form fungi).  This network of hyphae adds structure to the soil increasing its water holding capacity.

They can also be symbiotic to the plants roots. The mycorrhizal fungi may actually penetrate the root system, effectively extending the reach of the root many times and increasing the capacity of the plant to extract water and nutrients from the soil.

 

 

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Plants absorbing carbon dioxide

 

Plants absorb 30 times all man made emission.  This is a huge absorption of carbon dioxide. At first sight this would indicate that carbon levels should be dropping – yet they are rapidly rising – so what has gone wrong?

Unfortunately most of the carbon absorbed by plants goes straight back into the atmosphere.

 Plant materials are complex organic molecules which are readily degraded to simpler molecules, such as carbon dioxide.  This happens from a number of mechanisms.  The combination of UV light and oxygen in the atmosphere is highly destructive to these complex organic molecules.

Agricultural and forestry waste left on the surface and exposed to sunlight quickly breaks down to return carbon dioxide to the atmosphere.

 If they are not broken down by UV light there are likely to be decomposed by bacteria working in aerobic conditions.  These aerobic bacteria will release large amount of carbon dioxide back into the atmosphere.

In other words plants absorb large amounts of carbon but most is returned to the atmosphere.  It is often said that the largest emitter of carbon is coal fired electricity generation followed by close seconds such as farming and transport.

This is not true, the largest source of carbon entering the atmosphere, by far is the break down of plant material. Some 97% of the carbon entering the atmosphere is from degrading plant material.  The level of carbon in the atmosphere is a dynamic situation with carbon continuously entering and leaving the atmosphere. 

People often make the mistake of thinking of carbon as a static problem e.g. we should strive to take carbon out of the atmosphere and permanently store it. This has led to the mistaken view that forestry is storing carbon in the soil - mistaken, because the carbon is not permanently stored.

We should think of the atmosphere as a giant lake with carbon, like water, pouring in and out.  If there is more carbon pouring in the level will rise and if there is more carbon pouring out the level will drop.

Man made emission are a relatively small part of this carbon flow which is dominated by the natural extraction and return of carbon from the plants.  Man has upset the balance by increasing carbon emission and reducing the ability of plants to remove carbon.

 The critical issue is the rate at which carbon is being extracted versus the rate at which it is returned. 

A tropical rain forest rapidly absorbs carbon from the atmosphere, but carbon is equally rapidly returned.  Any carbon that may be captured in the soil is quickly washed away by the heavy tropical rain, so the system is close to being in balance with only a small reduction in atmospheric carbon.

A temperate forest, with a lower and more seasonal rainfall, on the other hand has a much slower rate of decomposition so there is time for the micro organisms to capture carbon into the soil, so there will be a reduction of carbon in the atmosphere. 

Every molecule will eventually return to the atmosphere but the rate of return will be  less than the rate of capture so the system is not in equilibrium and the balance of the carbon ends up captured in the soil.  Individual molecules will be entering and leaving the soil, may be at a fairly rapid rate, but there will still be a net increase in the total carbon in the soil. They are different molecules but still the net volume will be increasing.

Modern agriculture has of course changed the carbon balance and land that was once forest that has been converted to agriculture increasing the rate at which carbon is returned to the atmosphere so the net volume of carbon in the soil will be reduce over time.  Modern agriculture is a major net emitter of carbon. This is bad for the climate and bad for food production.

The technology of reducing the rate at which the plant based carbon returns to the atmosphere must be one of the most important technologies for safeguarding our future, yet it remains in a scientific backwater.

Bacteria and fungi both degrade dead organic material, but in very different ways. 

Bacteria are very effective at degrading soft organic material but have difficulty in digesting the hard material particularly the lignin in wood.

They can generate ionic bonds (Van de Waal forces) between the organic material and the soil particles which assist in retaining the carbon in the soil.

Anaerobic bacteria can release significant amounts of carbon dioxide and methane back into the atmosphere.  Anaerobic bacteria lead to lower green house emissions.

Bacteria are microscopic with no cohesion between individual bacteria. 

Fungi are very different. They send out hyphae to form a complex network of mycelium which can be huge.  In fact the largest living creature on the earth is a fungus.  This network reinforces the soil giving it mechanical strength which helps the soil resist wind and water erosion.  It also increases the pore size so the soil can hold more water.

The hyphae inject powerful enzymes into the organic material which can decompose even the hardest of woods.  They can also dissolve soil particles, even rocks, to release minerals for plant use.

Certain fungi form beneficial or symbiotic relationships with plants (mycorrhizal fungi).  The area or spread of the fungi is far greater than the roots of the plants increasing the nutrient supply to the plant.  Some fungi actually enter the root system and in return for minerals receive sugars from the plant.

 Fungi also stabilize the carbon in the soil, even their body mass, which is largely carbon, is significant and fungi can live for hundreds of years.

Whether the problem is looked on as a way of increasing food production or of absorbing carbon into the soil for long periods of time fungi play a crucial role.

Wicking beds can be used to capture the carbon captured by plants and retain in the soil.  Fungi are the most effective method of converting plant material into carbon in the soil. This retained carbon improves the soil, increasing the water holding capacity and making nutrients more available to the plant.

Fungi are particularly sensitive to water content,

Wicking beds provide this high humidity environment in which fungi flourish and can be part of that critical chain of converting carbon into soil. Special versions of the wicking bed have been developed to capture carbon within an agricultural system.

We have the technology now. Of course it can still be refined, as any technology can, but we have simple methods that work well right now.  Technology is not a problem.

The immediate problem is that the actions of individual farmers are determined (in the main) by short term economic considerations.  There needs to be a fundamental shift in the attitude of society and Governments away from seeing food production as just another economic commodity to be traded around the world and to regard the farm as a community asset to provide us with food security in the long term and to manage the climate.  This has to be given real meaning by Government action.

The immediate problem is there is no structure - legislative or preferably financial incentives - to make this happen.

Governments and the International community need to set up a system of financial incentives whatever the method, trading schemes, tax incentives, subsidies or whatever scheme is preferred. Farmers cannot be expected to make the changes so they can absorb carbon without some reward for their efforts and expenditure..

 

The costs would be well below other schemes such as carbon sequestration at the power stations.  In any case sequestration only reduces the rate at which carbon is emitted and does nothing to remove carbon from the atmosphere.

The wicking bed is a new generation of agricultural system which is more productive, improves water use and can capture carbon from the atmosphere to stabilize climate change and to improve soil quality.