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Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2008.
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| Other Authors: | |
| Format: | Thesis |
| Language: | English |
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Stellenbosch : University of Stellenbosch
2008
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| _version_ | 1867613739543429120 |
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| access_status_str | Open Access |
| author | Eustice, Tarryn |
| author2 | Hoffman, J. E. |
| author_browse | Eustice, Tarryn Hoffman, J. E. |
| author_facet | Hoffman, J. E. Eustice, Tarryn |
| author_sort | Eustice, Tarryn |
| collection | Thesis |
| dc_rights_str_mv | University of Stellenbosch |
| description | Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2008. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/3090 |
| institution | Stellenbosch University (South Africa) |
| language | English |
| last_indexed | 2026-06-10T12:40:56.191Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2008 |
| publishDateRange | 2008 |
| publishDateSort | 2008 |
| publisher | Stellenbosch : University of Stellenbosch |
| publisherStr | Stellenbosch : University of Stellenbosch |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/3090 Efficiency of irrigation practices for table grapes in the Hex River Valley Eustice, Tarryn Hoffman, J. E. Fey, M. V. University of Stellenbosch. Faculty of Agrisciences. Dept. of Soil Science. Irrigation efficiency Leaching Table grapes Irrigation scheduling Dissertations -- Soil science Theses -- Soil science Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2008. In order to produce table grapes of export quality economically, irrigation must be practised conservatively without adversely affecting the crop. To use water as conservatively as possible effective irrigation scheduling practices must be applied. The highest water use efficiency (WUE) is only possible if irrigation scheduling practices lower the amount of water applied, while at the same time they increase the yield. The first aim of this project is to investigate whether current irrigation practices make efficient use of water by comparing irrigation requirements determined using theoretical models with actual irrigation applied for two seasons (2005/6 and 2006/7). Secondly, the effect of cumulative irrigation on the chemical status of soil in 16 blocks was investigated to establish whether nutrient leaching as a result of differential water use may have had an influence on yield. Six blocks (three dripper and three microsprinkler blocks) were selected and irrigation requirements were determined using evaporation pan calculations, SAPWAT and Vinet and compared with actual irrigation applications. Furthermore, a yield-irrigation index (kg/m3) and an income-irrigation index (R/m3) were determined for each of the six blocks and compared. To investigate the effect of cumulative water use on the chemical status of the soils of 16 blocks, soil samples were taken and analysed for pH (1M KCl), EC (1:5); soluble cations and anions (Ca, Mg, Na, K, SO4, NO3, and Cl), ammonium acetate extractable cations (Ca, Mg, Na and K) and micro elements (Zn, Fe, Mn, Cu and B). The irrigation requirements predicted by the different irrigation scheduling methods are variable. For Vinet, the irrigation requirement determined for microsprinkler irrigation is much higher than that determined using the evaporation pan or SAPWAT approaches. Comparison of the irrigation applied to each of these blocks does not clarify whether any irrigation scheduling takes place. Results showed a relationship between the yield-irrigation index and income-irrigation index. It has not however been verified whether this relationship is statistically significant. Masters 2008-06-12T12:49:01Z 2010-06-01T09:06:00Z 2008-06-12T12:49:01Z 2010-06-01T09:06:00Z 2008-03 Thesis http://hdl.handle.net/10019.1/3090 en University of Stellenbosch application/pdf Stellenbosch : University of Stellenbosch |
| spellingShingle | Irrigation efficiency Leaching Table grapes Irrigation scheduling Dissertations -- Soil science Theses -- Soil science Eustice, Tarryn Efficiency of irrigation practices for table grapes in the Hex River Valley |
| title | Efficiency of irrigation practices for table grapes in the Hex River Valley |
| title_full | Efficiency of irrigation practices for table grapes in the Hex River Valley |
| title_fullStr | Efficiency of irrigation practices for table grapes in the Hex River Valley |
| title_full_unstemmed | Efficiency of irrigation practices for table grapes in the Hex River Valley |
| title_short | Efficiency of irrigation practices for table grapes in the Hex River Valley |
| title_sort | efficiency of irrigation practices for table grapes in the hex river valley |
| topic | Irrigation efficiency Leaching Table grapes Irrigation scheduling Dissertations -- Soil science Theses -- Soil science |
| url | http://hdl.handle.net/10019.1/3090 |
| work_keys_str_mv | AT eusticetarryn efficiencyofirrigationpracticesfortablegrapesinthehexrivervalley |