Informing Equitable Water and Food Policies through Accurate Spatial Information on Irrigated Areas in Smallholder Farming Systems

Accurate information on irrigated areas’ spatial distribution and extent are crucial in enhancing agricultural water productivity, water resources management, and formulating strategic policies that enhance water and food security and ecologically sustainable development. However, data are typically limited for smallholder irrigated areas, which is key to achieving social equity and equal distribution of financial resources. This study addressed this gap by delineating disaggregated smallholder and commercial irrigated areas through the random forest algorithm, a non-parametric machine learning classifier. Location within or outside former apartheid “homelands” was taken as a proxy for smallholder, and commercial irrigation. Being in a medium rainfall area, the huge irrigation potential of the Inkomati-Usuthu Water Management Area (UWMA) is already well developed for commercial crop production outside former homelands. However, information about the spatial distribution and extent of irrigated areas within former homelands, which is largely informal, was missing. Therefore, we first classified cultivated lands in 2019 and 2020 as a baseline, from where the Normalised Difference Vegetation Index (NDVI) was used to distinguish irrigated from rainfed, focusing on the dry winter period when crops are predominately irrigated. The mapping accuracy of 84.9% improved the efficacy in defining the actual spatial extent of current irrigated areas at both smallholder and commercial spatial scales. The proportion of irrigated areas was high for both commercial (92.5%) and smallholder (96.2%) irrigation. Moreover, smallholder irrigation increased by over 19% between 2019 and 2020, compared to slightly over 7% in the commercial sector. Such information is critical for policy formulation regarding equitable and inclusive water allocation, irrigation expansion, land reform, and food and water security in smallholder farming systems.

Innovation Meets Tradition in the Sheep and Goat Dairy Industry

Small ruminants, such as sheep and goats, are mostly raised in smallholder farming systems widely distributed throughout the world [...]

Gliricidia sepium (gliricidia).

G. sepium is an extremely versatile, fast-growing, nitrogen-fixing agroforestry tree that is adaptable to a wide range of humid and sub-humid climates and soil conditions including moderately acid and infertile. It is extremely easy to propagate and manage in a wide diversity of different smallholder farming systems to provide a multiplicity of high quality products and services and is a true multipurpose tree. It is one of the commonest and best-known trees in Central America and now has a pantropical distribution cultivated in villages, farms, backyards and along fence lines, paddy bunds, roadsides and terrace boundaries. It is probably the most widely cultivated multipurpose agroforestry tree after Leucaena leucocephala (Simons and Stewart, 1994) and has become increasingly popular due to the problems caused to Leucaena by the psyllid defoliator, Heteropsylla cubana. However, its value and benefits are not universally accepted as there is still debate over the quality of G. sepium forage.