Conservation Agriculture 

Conservation Agriculture (CA) is a term encompassing farming practices which have three key characteristics: 1. minimal mechanical soil disturbance (i.e. no tillage and direct seeding); 2. maintenance of a mulch of carbon-rich organic matter covering and feeding the soil (e.g. straw and/or other crop residues including cover crops); and 3. rotations or sequences and associations of crops including trees which could include nitrogen-fixing legumes. There are currently some 117 million hectares (about 8 percent of global arable cropland) in such systems worldwide, increasing by about 6 million hectares per year (www.fao.org/ag/ca). They cover all agro-ecologies and range from small to large farms. CA offers climate change adaptation and mitigation solutions while improving food security through sustainable production intensification and enhanced productivity of resource use.

Country examples of conservation agriculture

In Uzbekistan, where monocropping of cotton is common place, FAO has contributed to enhance the productivity of cotton through CA including no-till, diversification (rotation with wheat and grain legumes) and selected cover crops. This involved the establishment of demonstration plots and training in soil water dynamics, organic matter improvement and related soil stability measures, methodologies and techniques. The technologies introduced during the project in Tashkent resulted in improved soil quality, crop development and yields. The project also showed that farmers were willing to use the CA practices step by step with a well-tested crop rotation system.

In Egypt, CA was introduced in the rice-cropping systems of the Nile Delta, where more than 50 percent of the 3-5 million tones of rice straw residues produced annually are burnt in the field as a practical means of disposal. Rice in rotation with berseem (a forage legume) or wheat achieved yields under CA equal to those grown under conventional practices with savings in time, energy (fuel) and labour needed for land preparation and crop management. The project also demonstrated the advantages of CA practices for weed control, crop water consumption and improvement of soil conditions for crop development.

Farmers in Lesotho have been able to boost agricultural yields and increase food production by adopting CA. The practice, locally known as likoti, also contributes to combating soil erosion and to enhancing fertility. The socio-economic and environmental benefits help poor households to rehabilitate and strengthen their livelihood capital base and ultimately help rural communities to build system resilience in the face of widespread poverty and increasing vulnerability that affect the country. Results show that attending appropriate training is a crucial prerequisite for the correct adoption of likoti. However, training is more effective when trainers pursue true participation and when social capital among farmers is stronger. Further important determinants of adoption are the level of education and the economic incentives provided to vulnerable households (Silici 2010).

In Lempira, Honduras, farmers moved from a traditional slash and burn system to the Quesungual system. This CA system uses trees and mulch. An economic analysis of this transition showed that during the first two years maize and sorghum yields were about equal to those obtained with the traditional slash and burn system. From the third year, however, their yields increased, in addition, the system provided the farmer with firewood and posts, which gave an extra value to the production. Because of the increased production of maize, the quantity of stover increased as well; this could be sold as livestock fodder. Additionally, from the first year onwards, the farmer could rent out the land for livestock grazing, because of the increased biomass production. Usually this was done for two months. The application of the Quesungual system not only meets the household subsistence needs for fruit, timber, firewood and grains, but also generates a surplus which can be sold providing an additional source of income.

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last updated:  Thursday, December 30, 2010