000			03225nam a22002897a 4500
001			G91373
003			MX-TxCIM
005			20240517185738.0
008			240517s2009 ii ||||| |||| 00| 0 eng d
040			_aMX-TxCIM
041			_aeng
090			_aCIS-5478
100	1		_aWall, P.C. _8INT0255 _93735 _gSustainable Intensification Program
245	1	0	_aStrategies to overcome the competition for crop residues in Southern Africa : _bsome light at the end of the tunnel
260			_aNew Delhi (India) : _b4th World Congress on Conservation Agriculture, _c2009.
340			_aComputer File Printed
520			_aMost small-holder farmers in southern Africa rely on maize as their staple food and manage mixed crop/livestock systems where maize is the major crop and maize residues provide a vital source of livestock feed during the dry season when grazing areas are limited. Conservation agriculture on the other hand relies on ground cover with crop residues to achieve its potential to increase crop yields under rainfed conditions and increase soil health and system sustainability. The competition between the soil and animals for the scarce crop residues thus has become a major point for discussion and often disagreement. However, most analyses of total farm productivity during a transition to conservation agriculture from tillage-based agriculture assume that all of the farm will be converted to the new system in a relatively short period of time. This strategy, while conceptually simple, also results in the maximum competition for residues, and as a result tends to force a decision against CA before its promise of increased yields and system sustainability can be achieved. If the farm is converted gradually to CA, then competition is less, the farmer can learn to manage the new system properly under his/her conditions, and soil degradation on the farm can gradually be reverted while crop productivity increases. The reduced risk of crop failure with CA also allows diversification of crops on the farm, and may include the production of forage crops with markedly better nutritional quality than cereal crop residues. Using examples from farmer managed plots in southern Africa the paper will explore the effects on total productivity. However, there are other difficulties with surface residue retention, principally communal grazing rights after harvest and the prevalence of wild fires or bush fires. Both of these need to be taken into account and while the farmer can control aspects of the solution, overcoming the problems will involve important policy decisions at the community and district levels.
546			_aText in English
591			_a0903
650		7	_91064 _aCrop residues _2AGROVOC
650		7	_aConservation agriculture _92619 _2AGROVOC
650		7	_aSmallholders _91763 _2AGROVOC
651		7	_2AGROVOC _91954 _aSouthern Africa
711	2		_928220 _aWorld Congress on Conservation Agriculture _n(4th : _d4-7 February 2009 : _cNew Delhi, India)
773	0		_dNew Delhi (India) : 4th World Congress on Conservation Agriculture, 2009. _gp. 65-70 _tWorld Congress on Conservation Agriculture; 4: Innovations for improving efficiency, equity and environment _wG91363
942			_cCPA _2ddc _n0
999			_c6258 _d6258