Return to search

Spatial characterisation of natural terroir units for viticulture in the Bottelaryberg-Simonsberg-Helderberg winegrowing area

Thesis (MScAgric) -- University of Stellenbosch, 2001. / ENGLISH ABSTRACT: There is an increasing demand by the consumer for knowledge and understanding of the
origin of each wine produced. This origin is directly linked to the interaction between the
environment and grapevine, and therefore to the terroir. A terroir can be defined as a complex
of natural factors being expressed through the final product and must therefore be studied in
two steps, namely, the identification of relatively homogenous natural terroir units followed
by their ecophysiological characterisation.
The aim of this study was to characterise the Bottelaryberg-Simonsberg-Helderberg
wine growing area according to existing digital information and to identify natural terroir
units. The study area is situated to the southwest of Stellenbosch and covers an area of
approximately 25 000 ha.
Topography is a static feature of the landscape and affects the sunlight interception by a slope,
exposure of a site to winds and drainage of soil water and air. It forms an important
component of the terroir concept and has a strong interaction with the environmental
components of climate and soil. The study area is bordered by mountains and bisected by a
river valley resulting in a large variation in aspect and altitude affecting both spatial and
temporal temperature variability.
There is no doubt as to the important effect of climate on wine character and quality. A
number of indices can be used to describe the regional climate. The study area has a
Mediterranean climate with notable spatial variation of all climatic parameters due to its
complex topography and proximity to the ocean.
The effect of geology on wme character is less clear but appears to act through its
contribution to the physical properties of the soil. In the Bottelaryberg-Simonsberg-
Helderberg study area the geology is complex due to the high degree of tectonic movement
and mixing of parent material. In situ weathering of rocks is seldom the only source of soil
formation. Soil has a number of contributing factors affecting wine character and quality, inter alia, soil
colour, temperature, chemical composition, depth and texture (affecting the water supplying
properties of the soil). It is the last two that appear to have the most significant effect. Soil
depth affects the buffer capacity of the soil to temper climatic extremes and the water supply
has a well-recorded effect on vine growth and functioning. There is a high degree of soil
variation in the Bottelaryberg-Simonsberg-Helderberg study area that is difficult to represent
in soil associations. A pattern of soil distribution, however, can be noticed in relation to
landscape variation.
Terrain morphological units, altitude and aspect were used as pnmary keys for the
identification of natural terroir units. Broad soil categories and geological information were
included at a secondary level. This resulted in 195 units. These natural terroir units will form
the basis for future ecophysiological characterisation in order to determine possible future
cultivar distribution as well as the terroir effect on wine character. / AFRIKAANSE OPSOMMING: Daar is toenemende aanvraag vanaf die verbruiker vir kennis en begrip van die oorsprong van
elke wyn wat geproduseer word. Die oorsprong is direk aan die interaksie tussen die
omgewing en wingerd gekoppel, en daarom ook die terroir. Terroir kan omskryf word as die
kompleks van natuurlike faktore wat in die finale produk uitdrukking vind en studies daarvan
moet dus in twee stappe plaasvind, d.i. die identifisering van relatiewe homogene natuurlike
terroir eenhede gevolg deur die ekofisiologiese karakterisering daarvan.
Die doel van die studie was om die Bottelaryberg-Simonsberg-Helderberg wynproduserende
gebied te karakteriseer, met behulp van bestaande versyferde data en om natuurlike terroir
eenhede te identifiseer.
Topografie is 'n vaste landskapskenmerk en beïnvloed sonligonderskepping deur hellings,
blootstelling van 'n ligging aan wind en die dreinerin~ van grondwater en beweging van koue
lug. Dit is 'n belangrike deel van die terroir konsep en het sterk interaksie met
omgewingsfaktore van grond en klimaat. Die studiegebied word begrens deur berge en is
deursny deur 'n riviervallei, met groot variasie in helling en aspek. Beide hiervan beïnvloed
die ruimtelike- en daaglik-variasies in daaglikse maksimum temperatuur.
Die belangrike effek van klimaat op wynkarakter en kwaliteit is duidelik soos weerspieël deur
die beskikbaarheid van 'n aantal makroklimaatsindekse. Alle klimaatsparameters word deur
topografie beïnvloed. Temperatuur en relatiewe humiditeit word ook deur afstand vanaf die
see beïnvloed. Die studie area het 'n Meditereense klimaat, met merkwaardige ruimtelike
variasie van alle klimaatsparameters.
Die effek van geologie op wynkarakter is minder duidelik, maar het waarskynlik 'n effek op
die fisiese eienskappe van 'n grond. Die geologie in die Bottelaryberg-Simonsberg-
Helderberg studiegebied is kompleks, as gevolg van die hoë graad van tektoniese beweging
en vermenging van moedermateriaal. In situ vorming van gronde uit gesteentes vind selde
plaas: Grond het 'n groot aantal bydraende faktore, wat wynkarakter en -kwaliteit kon beïnvloed,
onder andere, grondkleur, -temperatuur, -chemiese samestelling, -diepte en -tekstuur (wat die
waterleweringsvermoë van die grond bepaal). Dit is veral laasgenoemde twee faktore wat
blykbaar die mees opvallendste effek openbaar. Gronddiepte bepaal die buffer kapasiteit van
die grond om klimaatsuiterstes te kan weerstaan en die waterleweringsvermoë het 'n
alombekende effek op wingerdgroei en funksionering. Daar is 'n hoë graad van grondvariasie
in die Bottelaryberg-Simonsberg-Helderberg studiegebied wat moeilik is om met
grondassosiasies weer te gee. Daar is wel 'n patroon van grond distribusie wat verband hou
met landskapvariasie.
Terrein morfologiese eenhede, hoogte en aspek is gebruik as primêre sleutels vir die
indentifisering van natuurlike terroir eenhede. Globale grondkategorieë en geologiese
inligting is op 'n sekondêre vlak gebruik. Dit het 195 eenhede tot gevolg. Die natuurlike
terroir eenhede sal die basis vorm vir toekomstige ekofisiologiese karakterisering, om die
terroir effek op wynkarakter te kan bepaal.

Identiferoai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/52459
Date04 1900
CreatorsCarey, Victoria Anne
ContributorsArcher, E., Saayman, D., Stellenbosch University. Faculty of AgriSciences. Dept. of Viticulture and Oenology.
PublisherStellenbosch : Stellenbosch University
Source SetsSouth African National ETD Portal
Languageen_ZA
Detected LanguageUnknown
TypeThesis
Format90 p. : ill. (some col.)
RightsStellenbosch University

Page generated in 0.0038 seconds