What are the characteristics of these two fields? Forest/fallow land Continuously cropped land.

Forest land Very little or no soil disturbance and plant roots enmesh soil particles to improve soil structure Production and recycling of foliage results in biological activity, humus formation and dark colored top soil with greater number of soil organisms. Tree canopy and litter fall protect soil from the erosive forces of wind and water. Soil remains moist for longer periods after rain Soil remains productively active.

Annual crop fields Soil may be productively dead. Biomass is largely removed, Soil may be tilled several times Reduced soil organism population Soil is much drier. Soil may be productively dead.

Traditionally shifting cultivation was used to simulate forest land conditions to maintain arable land productivity Shifting cultivation is no more feasible because of increased pressure on arable land due to: increased human population and related factors How then can we improve and sustain the productivity of a field such as this one?

Sustainable Food Production Systems Sustainable food production will require the creation of favorable conditions for soil life and the management of OM to ensure a fertile soil in which healthy plants can grow all the time as it is in the forest. - creation of forest land conditions on the arable land through the adoption of CONSERVATION AGRICULTURE

What is Conservation Agriculture? .CA is a farming system that conserves, improves and makes more efficient use of natural resources possible through integrated management of available soil, water and biological resources. This is achieved through a set of principles and practices that aim at sustaining the productivity of a given piece of land in an environmentally friendly and profitable manner

Principles of CA Three key principles Little or no soil disturbance Permanent soil cover Crop rotations/associations

Principles and practices. 1. Little or no soil disturbance No soil inversion, no incorporation of residue Direct seeding through crop/weed residue

Direct seeding - mechanical

Minimal soil disturbance

Principles and practices. 2. Ensure Permanent soil cover Food/Cover crops No burning Mulch

Principles and practices. 3. Practice Crop Rotations/associations Soyabean to be replaced with maize next season Maize to be replaced with soyabean next season

Intercropping

Summary of key features of CA No ploughing, disking or soil cultivation (no turning over of the soil) Crop and cover crop residue stay on the surface No burning of crop residue Permanent crop and weed residue mulch protects the soil Crop rotations, intercropping and cover crops are used to maximize biological controls The closed-nutrient recycling of the forest is replicated on the arable land

Center for No-Till Agriculture Building healthy soil for healthy plants for healthy people

Benefits of CA Economic Agronomic Environmental

Benefits of CA Economic benefits that improve production efficiency Time and labor savings Reduction in costs Higher efficiency

Benefits of CA Agronomic benefits that improve soil productivity Organic matter increase In-soil water conservation Improvement of soil structure and thus rooting zone

Environmental benefits Environmental benefits that protect the soil and make agriculture more sustainable Reduction of soil erosion Improvement of water quality Improvement of air quality Increase in biodiversity

Disadvantages of CA Disadvantages mentioned by some farmers: Equal or slightly lower grain yield during the first year Higher incidence of pest in the first year Sometimes too much mulch cover impedes germination of seeds High cost of equipment change over

Constraints to the adoption of CA Mind-set of the plough and burning Competition for crop residues Social issues – Communal grazing rights Weed control Insufficient fertility amendments Knowledge intensity Land tenure Equipment Excess soil water Time frame Policies Input market linkages

The CA Commandment Prelude “There is nothing wrong with our soil, except our interference” Edward Faulkner From Plowman’s Folly (1943) The commandment Thou shall live from the fruits of the soil. Therefore, thou shall feed, care for and protect thy soil with all thy might.

Center for No-Till Agriculture Building healthy soil for healthy plants for healthy people