In‐field Rainwater Harvesting: Mechanical Tillage Implements and Scope for Upscaling

Abstract

Around the world there is a large difference in crop yields between those obtained by commercial and subsistence farmers. There are many biophysical and socio‐economic reasons for this yield gap. With regard to in‐field rain water harvesting (IRWH), it is considered that crop yields in smallholder farms could be significantly improved by mechanizing the land as part of an IRWH tillage approach. This paper therefore presents the findings of a study that assessed the implements and procedures for applying IRWH. It involved the development of ridge and puddle ploughs. The subsistence farmers who evaluated the performance of the implements were generally satisfied with them. A five‐step procedure was developed for the application of the implements, and valuable lessons were learned with the first large‐scale demonstration of IRWH on croplands. Against the background of these positive results, the scope for upscaling was also explored. It was estimated that IRWH can probably be applied on millions of hectares in sub‐Saharan Africa, and particularly in the Southern African Development Community. Mechanization of IRWH should potentially contribute towards improving food security in sub‐Saharan Africa. Copyright © 2012 John Wiley & Sons, Ltd.

Integrated crop water management might sustainably halve the global food gap

“…Indicated 'low', 'ambitious', and 'max' pointer scenarios derive from the combination of each irrigation scenario with the respective SMC and WH intensity (defined in section 2.1.5), all for the time period 1980 to 2009. capital(Studer and Linger 2013, Falkenmark et al 2001, Mati et al 2007), addressing those in detail is beyond the scope of this broad-scale study of biophysical potentials. Although case studies show that often only 10%-20% of the land is unsuitable for WH and SMC adoption(Barron et al 2015, Kahinda et al 2008, van Rensburg et al 2012…”

Rainwater harvesting and conservation tillage increase maize yields in South Africa

“…The mechanization of in-field rainwater harvesting would be ideal on croplands compared to small areas of the homestead gardens. Anderson andvan Rensburg et al (2012) have attempted to address the mechanization of the in-field rainwater harvesting technique.…”

In-Field Rainwater Harvesting Tillage in Semi-Arid Ecosystems: I Maize–Bean Intercrop Performance and Productivity

“…A moldboard plow was used for cultivation, followed by disking to loosen the soil and for easy construction of the basin, ridge, and runoff structures. The first step in the construction of the IRWH structure was to determine the basin to runoff strip width (Van [14]. In this study, a 2:1 basin to runoff strip width was used, as recommended by Botha et al [11], Botha et al [23], and Tesfuhuney et al [24].…”

“…However, there are some limitations to this practice. For instance, the water that can be collected can be lost through evaporation due to the high evaporative demand [7,[14][15][16]. Intercropping is an old practice that has been used by smallholders to maximize land-use efficiency [17,18].…”