Friday, March 13, 2009
The conventionally preferred farmland is a flat piece of land that has easy access to water and is free of large rocks and boulders. Any variations in a landscape are often removed at great expense to reach this ideal. This is of course due to our preference for using animals and machines for doing the work, and growing single crops over large areas.
In fact, the variations in a landscape are a great asset for creating a rich, productive environment.
In a natural landscape, the variations and gradients in topography, orientation, soil structure, and mineral concentration create a variety of niches where different organisms thrive. Combined with natural cycles (seasons, day and night), these gradients give rise to energy and material fluxes through the landscape. These fluxes further specialize the niches, creating the right conditions for a diverse ecosystem. As we know, biodiversity is at the heart of creating a stable, efficient and productive ecosystem.
In permaculture, these gradients, cycles and patterns are observed and utilized for maximizing biodiversity and for situating plants, buildings, and other structures at the appropriate locations.
Water, often the limiting resource in an ecosystem, is a good example. We already saw how swales and ponds are a good tool for rejuvenating a landscape. They are especially important in Asia and Africa, where highly seasonal rainfall and temperature variations often lead to a marked dry season. Swales and ponds built on a natural slope harvest water with only small changes in the landscape, and make the rainwater available more uniformly through the year. By locating them properly, ponds can also reflect light towards plants, improve humidity, and make the local climate more moderate. Furthermore, swales and ponds create more niches in the landscape by introducing a water content gradient - water, water's edge and moisture gradients in the soil. Once you locate the plants according to their water needs, you don't need to waste energy on irrigation.
Similarly, by studying the patterns of wind, sunlight and natural animal movement, a permaculture site can be optimized to make it not only more productive, but also more habitable for humans, plants, and animals. With all these possibilities, why would you want a featureless land for a farm?