Healthy soil and sustainable growing

["TradingPostPaul" <tradingpost@riseup.net>]

from ISIS Press Release 02/01/08
Greening the Desert
How Farmers in Sahel Confound Scientists
http://www.i-sis.org.uk/greeningTheDesert.php

Scientists are catching up with farmers on how local knowledge and
cooperation can work miracles. Dr. Mae-Wan Ho and Lim Li Ching

Evidence of recovery has been coming from the ground since at least the
beginning of the present century. Fred Pearce reported in the New Scientist
in 2001 on how in Nigeria, Niger, Senegal, Burkina Faso and Kenya,
integrated farming, mixed cropping and traditional soil and water
conservation methods have been increasing per capita food production
several fold, keeping well ahead of population growth [5].

The use of sheep manure for fertiliser gave increased yields for farmers in
Kano, Nigeria. Planting leguminous crops increased nutrient levels in the
soil by fixing nitrogen from the air. Integration of crops and livestock
enhances nutrient cycling; legumes and manure return to the soil what crops
take out. The Kano region is the most agriculturally productive part of the
country, with increased yields of sorghum, millet, cowpeas and groundnuts.

A four-year study in eastern Burkina Faso challenged the assumption that
land is degrading largely due to human activities [6]. It found that
despite declining rainfall since the late 1950s and increasing populations,
there was no evidence of land degradation connected to human activities nor
a decline in food productivity. Conversely, yields of many crops have
risen, and there was no decline of soil fertility over 30 years.

These farmers did not achieve environmental sustainability through a
capital-intensive or high-tech path. In Burkina Faso, the increased yields
of sorghum, millet and groundnuts could hardly be attributable to increased
external inputs, because these crops received little fertilizer and were
cultivated largely with a hand hoe.

The scientists found that farmers have a rich repertoire of soil and water
conservation technologies, such as crop sequencing, crop rotation,
fallowing, weeding, selective clearing, intercropping, appropriate crop and
landrace selection, plant spacing, thinning, mulching, stubble grazing,
weeding mounds, paddocking, household refuse application, manure
application, crop residue application and compost pits. Mechanical
practices include perennial grass strips, stone lines, wood barriers, earth
barriers, brick barriers, stalk barriers, stone bunds, earth bunds and
living hedges.

Perhaps more important than the practices is the selective way they are
used, which vary with different field types, allowing optimal adjustment of
limited labour and inputs to the requirements of different crops and soils.
If land becomes limited, farmers do not need to invent new management
systems; they apply these soil and water conservation practices more
intensively. Farmers also apply land management practices only when and
where needed. Using their knowledge of crops and soils, they treat only the
parts of their field that need particular attention at any one time.

High local population densities, far from being a liability, are actually
essential for providing the necessary labour to work the land, dig terraces
and collect water in ponds for irrigation, and to control weeds, tend
fields, feed animals and spread manure [5]. As population densities
increase, farmers intensify their cooperation systems, grouping to tend
each other’s fields at busy periods, lending and borrowing land,
livestock and equipment, and swapping seed varieties.

People thus invest heavily in creating and maintaining social networks that
share land, labour, seeds, cattle grazing bushland, technologies and cash
[6]. These networks enhance the ability of farmers to farm sustainably and
efficiently by cooperation and reciprocity. They also allow people to
diversify their livelihoods, learn from each other, and minimize risks,
thus avoiding poverty traps.