Agro-climatic characterization of Lesotho for dryland maize farming was performed
using temperature and rainfall indices in a GIS environment. The temperature and rainfall
meteorological parameters were patched for missing data using the UK method for the
maximum and minimum temperatures. Missing daily rainfall data was patched using the
inverse distance method. Statistical evaluation of the patching methods showed good
performance. The spatial distributions of different temperature variables and indices were
mapped. Important meteorological parameters were the frost occurrence (first day, last
day and duration) and monthly and seasonal heat units. The onset of frost is early
(March) over the highland areas while the low- lying areas onset can be as late as June.
The last day of frost over the low- lying areas is mostly in August and on the other hand,
the highlands last day of frost is in November/December at some places. Rainfall
interpolation was done using the kriging method of the geostatistical analyst. Important
aspects mapped include monthly averages, seasonal amounts, annual amounts and
number of days of high daily rainfall. Wet season (October to April) rainfall was high
(>800mm) over the north to northeastern parts of the country while some areas over the
east and southern parts received less than 500mm of seasonal rainfall.
Climatic potential of maize under dryland farming in Lesotho was investigated using five
climatic suitability indices namely: probability of receiving heat units of greater than
1500GDD, probability of a frost-free growing season, probability of seasonal rainfall of
more than 500mm, probability of 15-day dry spells during December to February and the
slope of an area. For each of the above parameters a coverage layer was prepared in GIS
environment and the layers were overlaid to obtain the agroclimatic suitability map of
maize in Lesotho. The districts of Butha Buthe, Leribe and Berea are shown to have areas
which are highly favorable for maize cultivation under dryland farming while the
unsuitable areas are mostly over the high- lying areas (Mokhotlong, Thaba Tseka and
Qachaâs Nek) together with other parts of the southern lowlands.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ufs/oai:etd.uovs.ac.za:etd-08232005-104915 |
| Date | 23 August 2005 |
| Creators | Moeletsi, Mokhele Edmond |
| Contributors | Prof S Walker, Dr CH Barker |
| Publisher | University of the Free State |
| Source Sets | South African National ETD Portal |
| Language | en-uk |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.uovs.ac.za//theses/available/etd-08232005-104915/restricted/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to University Free State or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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