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- W1447764971 abstract "Soil fertility decline and erratic rainfall are major constraints to crop productivity on smallholder farms in southern Africa. Crop production intensification along with efficient use of chemical fertiliser is required to produce more food per unit area of land, while rebuilding soil fertility. The objective of this thesis was to identify appropriate crop production intensification options that are suitable to the socio-economic and biophysical conditions of selected smallholder maize-based farming systems in southern Africa. Three sites that formed a gradient of intensity of crop and livestock production were selected for the study. Murehwa in Zimbabwe is characterised by the largest intensity followed by Ruaca and lastly Vunduzi both in central Mozambique. In all three sites, maize is a key staple and cash crop. A literature review, field methods based on participatory research, and modelling tools were combined in analysing potential crop production options across an agricultural intensification gradient. A meta-analysis on maize grain yield under rain-fed conditions revealed that conservation agriculture required legume rotations and high nitrogen input use especially in the early years. Reduced tillage without mulch cover leads to lower yields than with conventional agriculture in low rainfall environments. Mulch cover in high rainfall areas leads to smaller yields than conventional tillage due to waterlogging, and improved yields under CA are likely on well drained soils. Crop productivity under conservation agriculture depends on the ability of farmers to achieve correct fertiliser application, timely weeding, and the availability of crop residues for mulching and systematic crop rotations which are currently lacking in southern Africa. An additive design of within-row intercropping was compared to a substitutive design with distinct alternating rows of maize and legume (local practice) under no-till in the Ruaca and Vunduzi communities of central Mozambique. Intercropping increased productivity compared to the corresponding sole crops with land equivalent ratios (LER) of between 1.0 and 2.4. Maize yield loss was only 6-8% in within-row intercropping but 25-50% in the distinct-row option. Relay planting of maize and cowpea intercropping ensured cowpea yield when maize failed thus reduced the negative effects of dry spells. The residual benefits of maize-pigeonpea intercropping were large (5.6 t ha-1) whereas continuous maize (0.7 t ha-1) was severely infested by striga (Striga asiatica). The accumulation of biomass which provided mulch combined with no tillage increased rainfall infiltration. Intensification through legume intercropping is a feasible option to increase crop productivity and farm income while reducing the risk of crop failure especially where land limitation. Cattle manure in combination with chemical fertiliser that included N, P, Ca, Zn, Mn were evaluated for their potential to recover degraded soils and to support sustainable high crop productivity in Murehwa, Zimbabwe over nine years. The experiment was established on sandy and clay soils in two field types. Homefields were close to the homestead and relatively more fertile than the outfields due to previous preferential allocation of nutrients. Maize grain yields in sandy soils did not respond to the sole application of fertiliser N (remained less than 1 t ha-1); manure application had immediate and incremental benefits on crop yields in the sandy soils. A combination of 25 t ha-1 manure and 100 kg N gave the largest treatment yield of 9.3 t ha-1 on the homefield clay soils, 6.1 t ha-1 on clay outfield, 7.6 t ha-1 on sandy homefield and 3.4 t ha-1 in the eighth season. Despite the large manure applications of up to 25 t ha-1, crop productivity and soil organic carbon build-up in the outfield sandy soils was small highlighting the difficulty to recover the fertility of degraded soils. Manure can be used more efficiently if targeted to fields closest" @default.
- W1447764971 created "2016-06-24" @default.
- W1447764971 creator A5074229966 @default.
- W1447764971 date "2013-01-01" @default.
- W1447764971 modified "2023-09-27" @default.
- W1447764971 title "Nuances and nuisances : Crop production intensification options for smallholder farming systems of southern Africa" @default.
- W1447764971 cites W110894812 @default.
- W1447764971 cites W1437390844 @default.
- W1447764971 cites W1486682118 @default.
- W1447764971 cites W1488286531 @default.
- W1447764971 cites W1488574179 @default.
- W1447764971 cites W1490388999 @default.
- W1447764971 cites W1505503746 @default.
- W1447764971 cites W1513066401 @default.
- W1447764971 cites W1529262044 @default.
- W1447764971 cites W1537288856 @default.
- W1447764971 cites W15404912 @default.
- W1447764971 cites W1544660463 @default.
- W1447764971 cites W1553039580 @default.
- W1447764971 cites W1553693322 @default.
- W1447764971 cites W1564977581 @default.
- W1447764971 cites W1582690188 @default.
- W1447764971 cites W1594035775 @default.
- W1447764971 cites W1604927526 @default.
- W1447764971 cites W168949063 @default.
- W1447764971 cites W171613998 @default.
- W1447764971 cites W172639899 @default.
- W1447764971 cites W173291398 @default.
- W1447764971 cites W180336283 @default.
- W1447764971 cites W1822301812 @default.
- W1447764971 cites W1844568697 @default.
- W1447764971 cites W1851187677 @default.
- W1447764971 cites W1855127131 @default.
- W1447764971 cites W1908309684 @default.
- W1447764971 cites W1963480119 @default.
- W1447764971 cites W1966108407 @default.
- W1447764971 cites W1966398159 @default.
- W1447764971 cites W1966904387 @default.
- W1447764971 cites W1967544423 @default.
- W1447764971 cites W1968374818 @default.
- W1447764971 cites W1969148119 @default.
- W1447764971 cites W1970690424 @default.
- W1447764971 cites W1971071892 @default.
- W1447764971 cites W1973561310 @default.
- W1447764971 cites W1974403185 @default.
- W1447764971 cites W1977315162 @default.
- W1447764971 cites W1979036971 @default.
- W1447764971 cites W1981738795 @default.
- W1447764971 cites W1982070737 @default.
- W1447764971 cites W1983965338 @default.
- W1447764971 cites W1984458812 @default.
- W1447764971 cites W1986446761 @default.
- W1447764971 cites W1986643805 @default.
- W1447764971 cites W1986809122 @default.
- W1447764971 cites W1987130928 @default.
- W1447764971 cites W1987500571 @default.
- W1447764971 cites W1988040430 @default.
- W1447764971 cites W1991337102 @default.
- W1447764971 cites W1991726671 @default.
- W1447764971 cites W1991996467 @default.
- W1447764971 cites W1992599498 @default.
- W1447764971 cites W1994916496 @default.
- W1447764971 cites W1995225012 @default.
- W1447764971 cites W1995973654 @default.
- W1447764971 cites W1997059821 @default.
- W1447764971 cites W1999027649 @default.
- W1447764971 cites W1999108911 @default.
- W1447764971 cites W1999615998 @default.
- W1447764971 cites W1999966160 @default.
- W1447764971 cites W2000497775 @default.
- W1447764971 cites W2002467160 @default.
- W1447764971 cites W2003166440 @default.
- W1447764971 cites W2003219879 @default.
- W1447764971 cites W2004631727 @default.
- W1447764971 cites W2005685209 @default.
- W1447764971 cites W2006279803 @default.
- W1447764971 cites W2006795408 @default.
- W1447764971 cites W2007534787 @default.
- W1447764971 cites W2009260090 @default.
- W1447764971 cites W2011680255 @default.
- W1447764971 cites W2013773427 @default.
- W1447764971 cites W2014339233 @default.
- W1447764971 cites W2014503785 @default.
- W1447764971 cites W2015168697 @default.
- W1447764971 cites W2018112236 @default.
- W1447764971 cites W2018539542 @default.
- W1447764971 cites W2019337404 @default.
- W1447764971 cites W2022960916 @default.
- W1447764971 cites W2023044705 @default.
- W1447764971 cites W2025284393 @default.
- W1447764971 cites W2026047931 @default.
- W1447764971 cites W2027013343 @default.
- W1447764971 cites W2028496041 @default.
- W1447764971 cites W2028523972 @default.
- W1447764971 cites W2029576571 @default.
- W1447764971 cites W2029744432 @default.
- W1447764971 cites W2029848914 @default.
- W1447764971 cites W2029855172 @default.
- W1447764971 cites W2031621405 @default.
- W1447764971 cites W2032233367 @default.