Wednesday, March 11, 2009
One of the major differences in conventional agriculture and natural ecosystems is in the number and complexity of components. Conventional agriculture is a fairly simple and linear system with very few components and pathways. In contrast, natural ecosystems are highly complex with hundreds, if not thousands of active components (microbes, insects, plants, animals) as well as numerous pathways through the system for energy and materials.
The needs of each component in a natural ecosystem are fulfilled by the outputs of multiple components, and in return, each provides multiple useful inputs for others. Furthermore, each need can often be fulfilled through multiple pathways. These needs are not only material requirements like nutrients and water, but also environmental requirements, like the right amount of sunlight, humidity, pest control, pollination and physical support.
This complexity has two direct benefits -
- Since everything is useful for something else, there is no 'waste' in the system, increasing energy and resource use efficiency.
- Due to multiple pathways for fulfilling each need, removal of a few components does not debilitate the system.
In permaculture, such complexity is intentionally designed into the system, creating a "food forest" with as many as 500-600 plant species, a few domesticated animal species, and attracting a large number of beneficial wild insects and birds. With this approach, a permaculture farm can produce an abundance of food practically throughout the year, without any chemical or mechanical inputs, and requiring far less labor than a conventional farm.
We need to shift our point of view significantly to realize how this is possible - we know that managing a farm with five plant species takes work. Managing a farm with fifty productive plant species will probably take even more work. What is perhaps a little un-obvious is that a farm with hundreds of plant species, a number of animal, and numerous insect and bird species can be completely self regulating and self sufficient, provided the components are chosen well to work together with each other and the local climate and landscape:
On a related note, the BBC series 'Natural World' recently showed the documentary A Farm for the Future, produced by wildlife film maker Rebecca Hosking:
Realising that all food production in the UK is completely dependent on abundant cheap fossil fuel, particularly oil, [Rebecca] sets out to discover just how secure this oil supply is.If you're in the UK, you can watch this program on the internet. Otherwise, it may be available on your local BBC channel.
Alarmed by the answers, she explores ways of farming without using fossil fuel. With the help of pioneering farmers and growers, Rebecca learns that it is actually nature that holds the key to farming in a low-energy future.