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Irrigation Systems:

make the right choice A pivot may seem like the ultimate solution, but it may be costly.

Irrigated agriculture plays a mayor role in the livelihoods of nations all over the world and although irrigation is one of the oldest known agricultural techniques, improvements are still being made in irrigation practices and methods. In this article Felix Reinders of the Agricultural Research Council: Institute for Agricultural Engineering in South Africa discusses different irrigation systems and the principles involved in choosing the correct system.

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rrigation is practiced on more than 300 million hectares in the world and it produces more than 40% of the food and fibre. On the African continent the area covered under irrigation is 13 million ha, which is 6% of the total cultivated area of the continent. Of this, almost 50% is concentrated in Northern Africa and about 75% are in five countries viz, South Africa, Egypt, Morocco, and Sudan. With an irrigation system it is also important that it must be used properly and that sound irrigation practices must be exercised to optimise yields. Irrigation implies that water is applied artificially to supply in the crop’s needs and the utilisation and management of the water must therefore be optimised from the dam wall releases, through the river or canal conveyance, on-farm storage and distribution and in-field application up to root zone storage. Classification of irrigation systems Various irrigation systems are available on the market today. They vary in terms of individual components and cost, and generally they can be classified into three groups.

The groups are: - Flood irrigation systems by which water that flows under gravitation is applied to the farm lands. This includes basin, border, furrow and short furrow. - Mobile irrigation systems which move over the farm land under its own power while it irrigates. This Irrigation group

include centre pivot, linear and travelling gun. - Static systems include all systems that remain stationary while water is applied. We distinguish between two types: - Sprinkler by which water is supplied above ground by means of sprinklers or sprayers. This includes permanent or portable systems such as quickcoupling, drag-line, hop-along, big gun, side-roll and boom irrigation systems. - Micro irrigation which includes micro-sprayers, mini-sprinklers and drip irrigation systems. Selecting an irrigation system Selecting an irrigation system for a site is not always straightforward, but Irrigation System

Flood Border Basin Furrow Short furrow Mobile Centre pivot Linear Travelling gun Static Sprinkler: Permanent Portable: Quick-coupling Dragline Hop-along Boom Side-roll Big gun Micro: Micro sprayers Mini sprinklers Drip

ProAgri Zambia 01

October 2015

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ProAgri Zambia 01

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