Your search found 3 records
1 van Koppen, Barbara; Nhamo, Luxon; Cai, Xueliang; Gabriel, M. J.; Sekgala, M.; Shikwambana, S.; Tshikolomo, K.; Nevhutanda, S.; Matlala, B.; Manyama, D. 2017. Smallholder irrigation schemes in the Limpopo Province, South Africa. Colombo, Sri Lanka: International Water Management Institute (IWMI). 36p. (IWMI Working Paper 174) [doi: https://doi.org/10.5337/2017.206]
Irrigation schemes ; Small scale systems ; Smallholders ; Social aspects ; Gender ; Water resources ; Water quality ; Infrastructure ; Rehabilitation ; Seasonal cropping ; Farmland ; Marketing ; Poverty ; Irrigated land ; Land tenure ; Land ownership ; Soils ; Vegetables ; Farmers ; Utilization ; State intervention / South Africa / Limpopo Province
(Location: IWMI HQ Call no: IWMI Record No: H048142)
(2 MB)
A survey of 76 public smallholder irrigation schemes in the Limpopo Province was jointly conducted by the International Water Management Institute (IWMI), Department of Agriculture, Forestry and Fisheries (DAFF), South Africa, and the Limpopo Department of Agriculture and Rural Development (LDARD), as part of the ‘Revitalization of Smallholder Irrigation in South Africa’ project. About one-third of those schemes was fully utilized; one-third partially utilized; and one-third not utilized in the winter of 2015; however, no single socioeconomic, physical, agronomic and marketing variable could explain these differences in utilization. Sale, mostly for informal markets, appeared the most important goal. Dilapidated infrastructure was the most important constraint cited by the farmers. The study recommends ways to overcome the build-neglect-rebuild syndrome, and to learn lessons from informal irrigation, which covers an area three to four times as large as public irrigation schemes in the province.
2 Nhamo, Luxon; van Dijk, R.; Magidi, J.; Wiberg, David; Tshikolomo, K.. 2018. Improving the accuracy of remotely sensed irrigated areas using post-classification enhancement through UAV [Unmanned Aerial Vehicle] capability. Remote Sensing, 10(5):1-12. (Special issue: Remote Sensing for Crop Water Management). [doi: https://doi.org/10.3390/rs10050712]
Irrigated sites ; Remote sensing ; Unmanned aerial vehicles ; Land use mapping ; Land cover mapping ; Satellite imagery ; Landsat ; Farmland ; Vegetation index ; Crops / South Africa / Limpopo Province / Venda / Gazankulu
(Location: IWMI HQ Call no: e-copy only Record No: H048752)
(2.23 MB) (2.23 MB)
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%.
3 Mpandeli, S.; Nhamo, Luxon; Moeletsi, M.; Masupha, T.; Magidi, J.; Tshikolomo, K.; Liphadzi, S.; Naidoo, D.; Mabhaudhi, T. 2019. Assessing climate change and adaptive capacity at local scale using observed and remotely sensed data. Weather and Climate Extremes, 26:100240. [doi: https://doi.org/10.1016/j.wace.2019.100240]
Climate change adaptation ; Assessment ; Remote sensing ; Drought ; Rain ; Temperature ; Water stress ; Resilience ; Risk reduction ; Strategies ; Smallholders ; Farmers ; Agricultural production ; Heat stress ; Vegetation index / South Africa / Limpopo / Capricorn
(Location: IWMI HQ Call no: e-copy only Record No: H049413)
https://www.sciencedirect.com/science/article/pii/S2212094719301380/pdfft?md5=07c6303aa103fe96c44be00ac162f087&pid=1-s2.0-S2212094719301380-main.pdf
https://vlibrary.iwmi.org/pdf/H049413.pdf
https://vlibrary.iwmi.org/pdf/H049413.pdf
(4.02 MB) (4.02 MB)
Climate variability and change impacts are manifesting through declining rainfall totals and increasing frequency and intensity of droughts, floods and heatwaves. These environmental changes are affecting mostly rural populations in developing countries due to low adaptive capacity and high reliance on natural systems for their livelihoods. While broad adaptation strategies exist, there is need to contextualise them to local scale. This paper assessed rainfall, temperature and water stress trends over time in Capricorn District, South Africa, using Standardized Precipitation Index, Thermal Heat Index, and Normalised Difference Vegetation Index (NDVI) as a proxy of water stress. Observed rainfall and temperature data from 1960 to 2015 was used to assess climatic variations, and NDVI was used to assess water stress from 2000 to 2019. Results show a marked increase in drought frequency and intensity, decreasing rainfall totals accompanied by increasing temperatures, and increasing water stress during the summer season. Long-term climatic changes are a basis to develop tailor-made adaptation strategies. Eighty-one percent of the cropped area in Capricorn District is rainfed and under smallholder farming, exposing the district to climate change risks. As the intensity of climate change varies both in space and time, adaptation strategies also vary depending on exposure and intensity. A combination of observed and remotely sensed climatic data is vital in developing tailor-made adaptation strategies.
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