No abstract

Although advances in remote sensing have enhanced mapping and monitoring of irrigated areas, producing accurate cropping information through satellite image classification remains elusive due to the complexity of landscapes, changes in reflectance of different land-covers, the remote sensing data selected, and image processing methods used, among others. This study extracted agricultural fields in the former homelands of Venda and Gazankulu in Limpopo Province, South Africa. Landsat 8 imageries for 2015 were used, applying the maximum likelihood supervised classifier to delineate the agricultural fields. The normalized difference vegetation index (NDVI) applied on Landsat imageries on the mapped fields during the dry season (July to August) was used to identify irrigated areas, because years of satellite data analysis suggest that healthy crop conditions during dry seasons are only possible with irrigation. Ground truth points totaling 137 were collected during fieldwork for pre-processing and accuracy assessment. An accuracy of 96% was achieved on the mapped agricultural fields, yet the irrigated area map produced an initial accuracy of only 71%. This study explains and improves the 29% error margin from the irrigated areas. Accuracy was enhanced through post-classification correction (PCC) using 74 post-classification points randomly selected from the 2015 irrigated area map. High resolution aerial photographs of the 74 sample fields were acquired by an unmanned aerial vehicle (UAV) to give a clearer picture of the irrigated fields. The analysis shows that mapped irrigated fields that presented anomalies included abandoned croplands that had green invasive alien species or abandoned fruit plantations that had high NDVI values. The PCC analysis improved irrigated area mapping accuracy from 71% to 95%.

The sustainability of agriculture is dependent on the characterization of project participants. The study investigated selected characteristics of participants in youth agriculture projects and constraints faced and proposed strategies for increased project productivity. Three in four (74%) of the projects were male owned and half (50%) of the owners only had primary education. As for project members, 53.8% were females with 59.3% of them in mixed vegetable and field crop projects. The project members were youthful with 84.4% aged 18-35 (25.3% were 18-25 years old, 25.3% were 26-30 and 33.8% were 31-35). Four in five (78.2%) project members were permanently employed. The projects had constraints that reduced their productivity, and those were mainly: (1) weak relationships with other stakeholders resulting in limited access to information, (2) lack of access to funding, and (3) poor land tenure. To improve productivity: (a) youth projects should be encouraged to form (or be part of) cooperatives, (b) initiatives such as NYDA and Mafisa should be strengthened to be more effective in servicing the youth projects, and (c) traditional authorities should establish committees with clear mandate and guidelines for improved land allocation. Strategies to improve productivity of youth projects should consider the described characteristics of participants in terms of gender, age, education and employment status.

No abstract

The study characterized farming households at three irrigation schemes in Mafefe Area at Lepelle-Nkumpi Municipality under Capricorn District of Limpopo Province and assessed the economic viability of their Water Users Association (WUA). The irrigation schemes were Mashushu, Fertilis and Mantlhane. Heads of household were older at Mashushu (average age=68) followed by Fertilis (59) and finally Manthlane (56). Household sizes ranged between 5 and 6. Some 21.7% of heads of household (37.5%-Mashushu, 20%-Fertilis and 7.7%-Manthlane) had no formal education, half (55%-Fertilis, 50%-Mashushu, and 53.8%-Manthlane) had primary while 25.3% (38.5%-Manthlane, 25%-Fertilis and 12.5%-Mashushu) had secondary education. Household income varied (average R26,991-Manthlane, R24,780-Mashushu, R21,807-Fertilis) across the schemes. The majority (88%) of farmers had ≤ 40% of income from farming. On average, individual farmers made profit in all schemes (R6,654.50-Mashushu, R4,565.59-Fertilis, R5,938.78-Manthlane). Production increased with cost of tillage (p<0.01)and marketing (p<0.05). The cost for operating the WUA was estimated at R15 500 / annum while the income was estimated at R16 700 / annum. The WUA for farmers in the study irrigation schemes would therefore be economically viable.