Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Efficiency of irrigation practices for table grapes in the Hex River Valley

Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2008.

Saved in:
Bibliographic Details
Main Author: Eustice, Tarryn
Other Authors: Hoffman, J. E.
Format: Thesis
Language:English
Published: Stellenbosch : University of Stellenbosch 2008
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613739543429120
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