African
governments and regional organisations like SADC increasingly
undertake efforts to address challenges such as poverty,
food insecurity, destruction of natural resources, and HIV/AIDS,
and the general stagnation of economic development. It becomes
obvious that agricultural development has been neglected
over the past decades, despite the clear evidence, that
broad-based agricultural development provides an effective
means for both reducing poverty and accelerating economic
growth. (FAO and World Bank, 2001). While per capita food
production has been raised in Asia and Latin America with
in the last decades, it is still declining in Sub-Saharan
Africa (IFAD, 2001). There are many reasons for this development.
But it is obvious that the farming systems in most parts
of Africa are not sustainable, they are no longer adapted
to a changing natural and socio-economic environment. They
are characterised by extremely low yields, exploitation
of natural resources ("soil mining") and increasing labour
input. Only a drastic change of farming systems, a turn
towards a more sustainable management of soils and an increased
labour productivity can improve the situation. Conservation
tillage, which has revolutionised the farming systems
in Latin America within the last decade, may offer a solution
to Sub-Saharan Africa, too.
Conventional
farming practices, especially burning of crop residues and
fallow vegetation, intensive hoeing or ploughing, and lacking
restitution of organic matter and plant nutrients, result
in soil degradation. Declining soil fertility linked to
lower water infiltration and storage results in declining
yields, increased vulnerability of crops to droughts, and
hence food insecurity and increasing poverty. This threatening
development calls for a radical change in the way farming
is done. What is required are farming systems, which imitate
tropical ecosystems, i.e., protect soils from rapid degradation,
are more productive, and in the same time reduce drudgery
especially of women and children.
Conservation
tillage responds to these requirements. This production
system provides the means that can prevent further destruction
of precious soils, increases rainwater use efficiency and
labour productivity, thereby ensuring higher and more stable
yields while it reduces production costs (especially the
energy input for tillage).
Conservation
tillage or farming is distinguished from other forms of
agricultural practices by the following three principles.
In order to gain the full benefit all three principles have
to be applied and build into the system. The three principles
are:
Minimum
disturbance of soil
Maintenance
of soil cover
Rotation
of crops
Minimum
disturbance of soil:Soil is a living organism and
has therefore to be treated as such. Soil disturbance through
tillage - opening up, loosening and inverting - destroys
soil organisms by exposing them to solar radiation and rapid
drying of the soil. The opening of the soil creates favourable
air and temperature conditions, which enhances the decomposition
of soil organic matter. With most soils inherently low in
cation exchange capacity, organic matter assures overriding
importance in the storage of nutrients in the soil. Therefore,
without sufficient quantities of organic matter in the soil,
even the efficiency and effectiveness of mineral fertilizers
is greatly reduced.
Practical
options include direct planting through mulch, using special
implements or minimum tillage where just a planting line
(furrow) is opened with a tine implement, or a planting
station with a hand hoe.
Maintenance
of a soil cover:Soils need to be protected against
the impact of raindrops, the speed of wind and the heat
of solar radiation by a cover of crop residues or cover
crops. Soil cover effectively reduces soil erosion by water
and wind. It impedes the loss of precious rainwater water
by run-off, allowing increased water infiltration and reduced
evaporation. Soil cover leads to a low and stable soil temperature
- overheating during daytime is prevented, as is rapid cooling-off
after sunset. Soil cover ultimately results in a more favourable
environment, also beneficial to soil organisms. Practices
such as burning of crop residues are juxtaposed to this
principle.
Crop
rotation: A suitable crop rotation, that combines
cereals and legumes helps in the management and maintenance
of rich soil nutrient regime and helps in the prevention
of the possible build up of pests, diseases and weeds.
Purpose of the African
Conservation Tillage Network
The
Network aims at facilitating identification, dissemination
and promotion of tillage systems and techniques that preserve
the fertility of the soil-water resource base, at the same
time offering sustainable high yields and high incomes.
To stimulate exchange
of information and experiences among researchers, extensionists
and farmers to facilitate wider accessibility to successful
CT technological options.
To encourage formation
of national CT networks in order to promote an institutional
and policy environment conducive for the dissemination
of conservation tillage practices.
To lobby for CT
at local, regional, national and international level.
Regional
focus: The Network started with a general focus on south-eastern
Africa. Working links exist to institutions in West and
North. The aim is, to expand ultimately covering the whole
of Africa.
Linkages:
ACT works closely with many national programmes, organisations,
networks and international organisations (e.g. FAO, SIDA/RELMA,
ATNESA, DMC, CIRAD) engaged in the promotion of conservation
tillage.
Major
activity focus: In partnership and liaison with in-country
organisations, and projects, the Network will:
Stimulate in-country
and international networking
Promote establishment
of national conservation tillage networks
Set up databases
accessible to members on relevant literature, institutions
and persons, and other technical aspects such as cover
crops/green manure, CT implements
Publish a quarterly
newsletter
Initiate and support
thematic working groups, field days and other awareness
programmes/activities
Test and compare
CT technologies and dissemination approaches with farmer
groups in selected pilot regions
Lobby for CT at
all relevant levels
Prepare training/educational
materials for dissemination into schools and institutions
Contact
the Secretariat for more information on any of these activity
areas.
National
Conservation Tillage Networks and in-country partners
form the basis of ACT.
The
Network Secretariat: is based at CIRAD Zimbabwe in Harare.
The secretariat, headed by a Regional Co-ordinator undertakes
the day-to-day co-ordination of ACT activities including
mobilisation of resources for the implementation of planned
activities.
The
Steering Committee: composed of 12 members drawn from
stakeholder groups guides the Network in policy matters.
Network
funding: The network secretariat and network activities
are at present funded by the German Government and technically
supported by GTZ. Some specific activities are funded by
network partners. In the long term, the Network aims to
self-finance its operations from membership fees and contributions
from partners.
The
Steering Committee is the policy governing body of the Network.
It is composed of persons from national institutions, regional
networks, the private sector, international research institutes
and development agencies. The Director of the implementing
agency and the Network Coordinator are ex-officio members.
Currently
the committee is composed of the following:
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