Current approaches to agroecology were strongly promoted by the International Assessment on Agricultural Knowledge, Science and Technology for Development (IAASTD) process. `Agroecology’ was a major feature of reports from a host of NGOs on the IAASTD. One of the surprising and unacceptable outcomes of the IAASTD process was not its general content, but in the way its content has been selectively cited, paraphrased, and even twisted, to support factional interests.
The IAASTD report continues to claim that the basic paradigm of agroecology “…is that the more similar the agricultural, forestry and cattle-farming ecosystems are to the natural ecosystem the more sustainable are medium- and long-term production and other environmental services, such as the recycling of nutrients, carbon sequestration in soils, and water percolation, detoxification, regulation and storage”. Perhaps so, but agroecology then insists on biodiverse agroecosystems only, in the apparent belief that natural ecosystems are all biodiverse (and would collapse if not biodiverse).
Real ecologists know that this is not so: there are many stable monodominant plant systems providing ecosystem properties – for example, mangroves and turtle-grass vegetation around tropical shores. The irony of an insistence on crop diversity is that major Old World cereals (rice, wheat, rye, oats and barley) all were domesticated from monodominant vegetation of their immediate wild relatives and all now, especially rice, need no intercropping to succeed. Crop monocultures are directly based on apparently rock-solid but monodominant natural vegetation. The exception is maize with no monodominant wild relative. Interestingly, maize is the crop that among the cereals is the most useful in intercropping – for example, the noted maize/bean/squash intercrop.
This natural monodominance is an ecological fact but will never ever be accepted by those agroecologists claiming that crop agroecosystems must be biodiverse in a mimic of nature. This is simply wrong.
Even for forestry, monodominance of wild species is found: successful plantations word-wide of teak, Caribbean pine and Eucalyptus and other species are based on monodominant natural vegetation. Janzen in 1974 suggested that the existence of monodominant tropical forest “falsifies the dogma that diversity is mandatory for ecosystem stability in highly equitable climates”: plant ecologists should know this.
Real agroecology must be based on real ecological facts, rather the dogma that more biodiversity is always better.
Dave Wood