In the context of food-security in the world's rain forest zones, I wish to draw to your attention the work of Inga Foundation(IF)'s Land for Life Program in Central America. Since 2012, IF has been extending a model agroforestry livelihood as an alternative to slash-and-burn subsistence agriculture. At the heart of the four-component model lies lies the agroforestry technique known as alley-cropping (a-c) (aka: hedgerow intercropping) using trees of the genus Inga. This technique was proven scientifically during 16 years of research and development by researchers in the University of Cambridge, working in both Central America and Cambridge.
This series of projects (1986-2002) investigated the ecology of slash-and-burn (s-b) agriculture in rain forests and, taking lessons from the functioning of the tropical rain forest itself, developed and tested a number of bare-soil and a-c techniques vis a vis their ability, or lack of ability, to sustain the production of basic grains (maize and beans grown in rotation). The only system to emerge successfully from 7 years' rigorous trials was a-c using Inga spp.; with the caveat that it be supplemented by small additions of rock-phosphate. IF was founded in 2007 to implement these findings with target families in northern Honduras. IF's present program began in 2012; aiming to recruit 40 families per year to an integrated agroforestry model enabled by Inga a-c, but including less intensively-managed agroforest systems for the production of tropical fruits and fine timber.
Further experimentation by IF in this program led to the successful use of Inga a-c supplemented, not only, by rock-phosphate, but also, by Dolomitic lime and K-Mag. This combination of mulch from the Inga and supplementary minerals yielding P, Ca, K, Mg, S and other micro-nutrients, has proved itself unique in restoring to fertility soils degraded by decades of repeated s-b. We know of no other system capable of this.
Soils in the world's tropical rain forest zones are typically highly-weathered and leached; such Ultisol-Oxisol soil types comprise two thirds of the available soil areas in these zones. Achieving food-security and climate-resilience on them is paramount in today's world. Today IF has just under 500 families implementing Inga a-c and related systems. None have reverted to s-b since adoption and all have transformed their nutrition and livelihoods with these systems. The Inga a-c system has proved itself resilient to climatic extremes, including prolonged drought and violent storms. In the 2019 drought, the only farmers taking crops of basic grains were those using the Inga system. The deep Inga mulch conserved soil moisture beneath it.
A full account of the history of the Cam projects and IF's present program can be found here:
Hands, M.R. (2021)
"The search for a sustainable alternative to slash-and-burn in the world's rain forests: The Guama Model and its implementation".
Royal Society Open Science. Vol. 8: Issue 2.
The Royal Society. London.
https://doi.org/10.1098/rsos.201204
先生 Mike Hands