Longitudinal analysis of a long-term conservation agriculture experiment in Malawi and lessons for future experimental design
R. M. Lark,Ivy Sichinga Ligowe,Christian Thierfelder,N. Magwero,W. Namaona,Keston Njira,I. Sandram,Joseph G. Chimungu,Patson C. Nalivata +8 more
TLDR
In this article, a longitudinal analysis of 10 years of data from the Chitedze Agriculture Research Station in Malawi was performed to understand the joint effects of variations between the seasons and particular contrasts among treatments on yield of maize.Abstract:
Resilient cropping systems are required to achieve food security in the presence of climate change, and so several long-term conservation agriculture (CA) trials have been established in southern Africa – one of them at the Chitedze Agriculture Research Station in Malawi in 2007. The present study focused on a longitudinal analysis of 10 years of data from the trial to better understand the joint effects of variations between the seasons and particular contrasts among treatments on yield of maize. Of further interest was the variability of treatment responses in time and space and the implications for design of future trials with adequate statistical power. The analysis shows treatment differences of the mean effect which vary according to cropping season. There was a strong treatment effect between rotational treatments and other treatments and a weak effect between intercropping and monocropping. There was no evidence for an overall advantage of systems where residues are retained (in combination with direct seeding or planting basins) over conventional management with respect to maize yield. A season effect was evident although the strong benefit of rotation in El Nino season was also reduced, highlighting the strong interaction between treatment and climatic conditions. The power analysis shows that treatment effects of practically significant magnitude may be unlikely to be detected with just four replicates, as at Chitedze, under either a simple randomised control trial or a factorial experiment. Given logistical and financial constraints, it is important to design trials with fewer treatments but more replicates to gain enough statistical power and to pay attention to the selection of treatments to given an informative outcome.read more
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Increasing zinc concentration in maize grown under contrasting soil types in Malawi through agronomic biofortification: Trial protocol for a field experiment to detect small effect sizes.
Lester Botoman,Lester Botoman,Patson C. Nalivata,Joseph G. Chimungu,Moses W Munthali,Elizabeth H. Bailey,E. Louise Ander,R. Murray Lark,Abdul-Wahab Mossa,Scott D. Young,Martin R. Broadley +10 more
TL;DR: This trial protocol describes a field experiment which aims to assess the potential of agronomic biofortification to improve the grain Zn concentration of maize, the predominant staple crop of Malawi.
Journal ArticleDOI
Performance of Push–Pull Technology in Low-Fertility Soils under Conventional and Conservation Agriculture Farming Systems in Malawi
Saliou Niassy,Mawufe Komi Agbodzavu,Bester Tawona Mudereri,Donwell Kamalongo,Ivy Sichinga Ligowe,Girma Hailu,Emily Kimathi,Zwide D. Jere,Nathan Ochatum,Jimmy O. Pittchar,Menale Kassie,Zeyaur R. Khan +11 more
TL;DR: In this paper , a focus group discussion was conducted to evaluate the performance of push-pull technology in low-fertility soils and two farming practices, minimum-tilled conservation agriculture practice (CA), and conventionally tilled practice (CP), in contrasting agroecological zones at the Chitedze, Mbawa, and Chitala stations in Malawi.
Journal ArticleDOI
Conservation Agriculture Affects Grain and Nutrient Yields of Maize (Zea Mays L.) and Can Impact Food and Nutrition Security in Sub-Saharan Africa
Yamdeu Joseph Hubert Galani,Ivy Sichinga Ligowe,Martin Kieffer,Donwell Kamalongo,A M Kambwiri,Pamela Kuwali,Christian Thierfelder,Andrew J. Dougill,Yun Yun Gong,Caroline Orfila +9 more
TL;DR: In this paper , the authors assessed the grain yield, macro-and micronutrient mineral content, and nutrient yield of eight maize varieties grown in Malawi, and how these are affected by conservation agriculture (CA) practices over two seasons.
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The effect of water deficit and livestock stocking density on soil organic carbon stocks in Namibia
TL;DR: In this paper , the influence of water deficit and livestock stocking density on soil carbon stocks was assessed, and the results showed that the impacts of a changing climate and changes in the intensity of grazing must be considered together to predict effects on the soil organic carbon stock.
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The effect of water deficit and livestock stocking density on soil organic carbon stocks in Namibia
TL;DR: In this article, the influence of water deficit and livestock stocking density on soil carbon stocks was assessed, and the results showed that the impacts of a changing climate and changes in the intensity of grazing must be considered together to predict effects on the soil organic carbon stock.
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