Thesis (MScFor)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The role that forestry plays in climate change mitigation is well recognized by countries that
ratified the Kyoto protocol agreement. Though climate change mitigation strategies provide a
strong incentive to quantify current patterns of forest carbon sources and sinks, this exercise
(carbon accounting) is not as simple as it sounds. This is proven by the vast number of
techniques and methodologies available, from models to softwares programmes created in
response to the need to estimate carbon sequestration.
The study aimed at gaining an understanding of the current carbon sequestration estimation
methodology and models in use by the South African Forestry Industry. A survey was
undertaken amongst forestry industry stakeholders in which 77% of respondents agreed to the
need for a carbon sequestration model for South Africa. This model should have qualities that
the forestry industry and all stakeholders agreed with. .
A search of freely available models and software was conducted. The aim was to find freely
available model(s) that would be readily applicable and adoptable to South African
conditions.
A Multi Criteria Analysis was carried out using “ideal qualities” for a carbon model as
weighting. This resulted in the selection of two models, CASMOFOR and CBM CFS 3,
which obtained the highest sum product total from the analysis. These together with FICAT,
which came as a recommendation from the questionnaire survey, were compared in the
analysis. Carbon values were calculated from yield table volumes by Kotze et al. (2012). A conversion
of these volumes to biomass and carbon was done using Dovey (2009) biomass expansion
factors and a biomass to carbon conversion value of 0.5 g C/g dry matter, following
procedures by Matthews (1993).
The first comparison was made on how the model results related to the yield table estimates
from Kotze et al. (2012). When carbon values were compared per hectare, it was found that
the FICAT model differed significantly from the rest.
A second comparison looked at the models’ prediction of the carbon accumulated in NCT’s
Enon plantation outside Pietermaritzburg. The Hungarian model, CASMOFOR, was the
better predictor as it produced the lowest Mean Squared Error (MSE).
Based on the results from the survey and model analysis a number of recommendations can
be made regarding the current carbon accounting situation in South Africa. One of the main recommendations is that information sharing among the industry’s stakeholders should
improve if the industry is to reach consensus on which methodology to adopt in their business
practices. / AFRIKAANSE OPSOMMING: Die rol wat bosbou speel in klimaatsverandering-bekamping is welbekend onder lande wat die
Kyoto protokol ooreenkoms onderteken het. Alhoewel klimaatsverandering-bekamping
strategieë ‘n sterk aansporing bied om huidige patrone van woudkoolstof bronne en sinkte te
kwantifiseer, is hierdie oefening nie so maklik soos dit klink nie. Die bewys hiervan is die
groot aantal tegnieke en metodes, wat wissel van modelle tot sagteware programme wat
ontwikkel is om koolstofsekwistrasie te meet.
Die doelwit van die studie was om die huidige koolstofsekwistrasie metodes en modelle wat
deur die Suid Afrikaanse Bosbou Bedryf gebruik word, beter te verstaan. ‘n Vraelysopname
is onderneem onder bosbou-industrie deelnemers, waarin 77% van respondente saamgestem
het dat dit nodig is dat Suid Afrika ‘n koolstofsekwistrasie model moet hê. Die model moet
eienskappe hê waarmee die bosbou-industrie en alle deelnemers saamstem.
‘n Soektog na vrylik beskikbare koolstofmodelle en sagteware programme is onderneem. Die
doelwit was om modelle te vind wat geredelik aangepas kan word vir Suid Afrikaanse
toestande. ‘n Multi-kriteria analise is uitgevoer met die “ideale eienskappe”vir ‘n
koolstofmodel as gewigte. Die resultaat was die seleksie van twee modelle, CASMOFOR en
CBM CFS 3, wat die hoogste telling in die ontleding behaal het. Hierdie modelle, tesame met
FICAT, wat aanbeveel is deur respondente van die vraelys opname, is vergelyk in ‘n
ontleding. Koolstofwaardes is bereken vanaf opbrengstabelle wat deur Kotze et al. (2012) ontwikkel is.
Die omsetting van hierdie volumes na biomassa en koolstof is gedoen deur Dovey (2009) se
biomassa uitbreidingsfaktore en ‘n biomassa na koolstof omsettings faktor van 0.5 g C/g
droëmassa te gebruik (Matthews, 1993). In die eerste vergelyking van die modelle is gekyk
hoe die modelle vergelyk met koolstof berekeninge vanaf die Kotze et al. (2012)
opbrengstabelle. Wanneer koolstofwaardes per hektaar vergelyk word is gevind dat FICAT
beduidend verskil van die ander modelle. In ‘n tweede vergelyking is gekyk na hoe die
modelle die koolstof wat in NCT se Enon plantasie buite Pietermaritzburg versamel is,
voorspel. Die Hongaarse CASMOFOR model was die beste voorspeller. Anders as die
FICAT en CBM CFS 3 modelle het dit die laagste Gemiddelde Vierkante Fout gehad.
Na gelang van die resultate van die vraelysopname en die modelontleding kan ‘n aantal
aanbevelings gemaak word oor die huidige koolstofberekening situasie in Suid Afrika. Een van die hoof aanbevelings is dat die uitruil van inligting tussen industrie deelnemers moet
verbeter as die bedryf eenstemmigheid oor die metode van koolstofberekening wil bereik.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/86247 |
| Date | 04 1900 |
| Creators | Ndalowa, Dan |
| Contributors | Ham, Cori, Ham, Hannel, Stellenbosch University. Faculty of AgriSciences. Dept. of Forest and Wood Science. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
| Format | 90 p. : ill. |
| Rights | Stellenbosch University |
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