May 17, 2016

The Epitome of Sustainability

Found this little gem of info on "the epitome of sustainability" - multistrata agroforestry.
Multistrata agroforestry systems go by many names – food forests, edible forest gardens, tropical homegardens, and more. What they have in common is their structure – multiple layers of vegetation, typically one or more layers of trees, with further layers of shrubs, vines, herbaceous species, and often fungi and/or livestock.

These “agroforests” can be at a tiny backyard scale or big enough to cover 50-70% of entire islands. Contemporary commercial examples include coffee and cacao under nitrogen-fixing shade trees. Multistrata systems go back 13,000 years in Java, and today are practiced on an estimated 100 million hectares globally (247 million acres), mostly in the humid tropics. Home-scale systems appear quite viable in cold climates, but models of commercial cold-climate hard to find – in deed development of such systems is one of our goals.

Scientists have called tropical homegardens “the epitome of sustainability” and have identified many benefits of these systems:
  • Multistrata agroforestry systems sequester outstanding amounts of carbon – some as high as 40 tons per hectare per year (t/ha/yr). This compares extremely favorably with often-recommended carbon farming strategies like no-till (0.3 t/ha), “regenerative organic” annual crops (2.3), and managed grazing (0.3). Some even sequester carbon at faster rates than adjacent natural forest!
  • Tropical homegardens have the highest levels of biodiversity of any human land management technique. For example, Mesoamerican homegardens average 348 species per hectares (149/acre).
  • In some cases these systems produce more food than monocultures – sometimes much more! For example, in Brazilian oil palm monocultures, oil yields average 5 t/ha. Polycultures of oil palm, with the addition of fruiting vines, nitrogen-fixing trees, and other elements, produce 8.7 t/ha of oil, plus the additional products!

The source of this quote and the image mashup above are Eric Toensmeier and Jonathan Bates of Paradise Lot blog. They are the guys who have done it. They have years of experience having created or helped create several permaculture food forests. See their 2013 book, for example: Paradise Lot: Two Plant Geeks, One Tenth of an Acre, and the Making of an Edible Garden Oasis in the City

Eric Toensmeier's next book is about carbon sequestration potential of multistrata agroforestry systems.

UPDATE: The new book is already out in March. It's called "The Carbon Farming Solution: A Global Toolkit of Perennial Crops and Regenerative Agriculture Practices for Climate Change Mitigation and Food Security". Paul Hawken says the book "describes the foundation of the future of civilization."