Sustainability of the soybean industry relies on the growth of new industries and the continued improvement of seeds for utilization. Grower adoption and growth of the edamame industry has been slow in part due to insufficient information on its potential profitability and marketability. As such, the first and second objectives of this thesis aimed at 1) determining production costs of hand-harvested fresh edamame enterprise and 2) exploring consumer willingness-to-pay (WTP) for fresh, local, organic, and "on-the-stalk" marketed edamame. Sucrose, raffinose, and stachyose sugars hold tremendous implications for utilization of soybean seeds in livestock, soyfood, and probiotics industries. Current sugar phenotyping methods using high-performance liquid chromatography (HPLC) are costly and inefficient. Therefore, the third objective of this study was to develop calibrations to predict sugar content using near-infrared reflectance spectroscopy (NIRS). Results showed that labor accounted for 72% of production costs for edamame pods, which largely limits its profit potential. Mean WTP for fresh and local edamame exceeded their frozen and non-local counterparts by 94 and 88 cents, respectively. In addition, mean WTP for organic edamame exceeded non-GMO edamame by 33 cents. Pro-environmental attitudes appeared to be a consistent driver of WTP these three attributes. Meanwhile, a 40-cent discount for "on-the-stalk" edamame compared to pods indicates convenience may also be a factor in edamame marketability. Calibration development for sucrose and stachyose was successful, with R2cal, R2cv, RMSEC, and RMSECV of 0.901, 0.869, 0.516, and 0.596, and 0.911, 0.891, 0.361, and 0.405, respectively. Alternative methods should be investigated for quantification of raffinose. / Master of Science / Sustainability of the soybean industry relies on the growth of new industries and the continued improvement of seeds for utilization. Grower adoption and growth of the edamame industry has been slow in part due to insufficient information on its potential profitability and marketability. As such, the first and second objectives of this thesis aimed at 1) determining production costs of hand-harvested fresh edamame and 2) exploring relative marketing potential of fresh, local, organic, and "on-the-stalk" edamame. Sucrose, raffinose, and stachyose sugars hold tremendous implications for utilization of soybean seeds in livestock, soyfood, and probiotics industries. Current methods of quantifying sugar are costly and time inefficient. Therefore, the third objective of this study was to develop prediction models to estimate sugar content using near-infrared reflectance spectroscopy (NIRS). Results showed that labor accounted for 72% of production costs for edamame pods, which largely limits its profit potential. Fresh and local edamame showed considerable marketing potential over frozen and non-local edamame. In addition, organic edamame showed marginal marketing benefit over non-GMO. Pro-environmental attitudes were an important driver of these results. Meanwhile, on-the-stalk edamame shows poor marketing potential, likely due to preference for convenience of food preparation in the U.S. NIRS prediction models for sucrose and stachyose showed strong predictive accuracy and low error, suggesting potential for implementation. The prediction model for raffinose, however, remained poor.

Thesis (MScAgric)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: Near infrared reflectance spectroscopy (NIRS) was evaluated as a tool to predict the chemical composition of ostrich meat, mutton and feedstuffs. Seventy-three calibrations were developed. NIRS analyses were conducted on an InfraAlyzer 500 spectrophotometer between 1100 and 2500 nm wavelengths. Near infrared reflectance calibrations were developed for (i) the proximate chemical composition of ostrich meat; (ii) the proximate chemical and mineral composition of mutton; (iii) the chemical composition and digestibility of lupins, full-fat canola and the determination of alkaloids in lupins; (iv) the chemical composition and digestibility of winter grains and maize; (v) the chemical composition and digestibility of cereal hay, cereal straw, wheat stubble and alfalfa-grass/hay mixtures. The chemical composition of different types of winter grain produced in the Western Cape area of South Africa, as well as the chemical composition and digestibility of winter grain hay and straw produced in a Mediterranean rainfall area were also determined. Near infrared reflectance spectrometry proved to be successful for the prediction of crude protein (CP) and fat in both animal species, as well as for ash and dry matter (DM) in freeze-dried mutton. Accurate calibrations were also developed for certain minerals (K, P, Na, Mg, Fe and Zn). Calibrations proved to be accurate for all the relevant chemical constituents in lupins, as well as the DM, CP and fat calibrations in full-fat canola. The alkaloid calibration showed potential although more samples should be included for a more accurate calibration. Winter grain calibrations were accurate for fat, acid detergent fibre (ADF), in vitro organic matter digestibility (IVOMD), lysine and methionine. All chemical composition calibrations of maize, except for ash, were accurate for future prediction. Chemical composition calibrations of wheat stubble and alfalfa-grass hay mixtures resulted in prediction with similar or slightly higher accuracy than calibrations reported in the literature. The calibrations developed for cereal hay and straw were not suitable for prediction purposes. Possible reasons were discussed to explain these inaccurate calibrations. Variation shown between different types of cereal grain (2-row barley, 6-row barley, oats, wheat and triticale) accentuated the need for the analysis of different batches of grain produced under different conditions for use in animal feed. The chemical composition and digestibility of winter grain straw and hay were also obtained. These values provide a database for calculation of inclusion levels of these feedstuffs in animal diets. These investigations showed the NIRS to be a successful and rapid tool for the prediction of the chemical composition of ostrich and lamb meat and locally produced feedstuffs. / AFRIKAANSE OPSOMMING: Naby infrarooi refleksie spektroskopie (NIRS) is geëvalueer as 'n metode om die chemiese samestelling van volstruis- en skaapvleis, asook voedingsgewasse te voorspel. Drie en sewentig kalibrasies is ontwikkel. NIRS ontledings is gedoen met ‘n InfraAlyzer 500 spektrofotometer tussen die golflengtes 1100 en 2500 nm. Naby infrarooi refleksie kalibrasies is ontwikkel vir (i) die basiese chemiese samestelling van volstruisvleis; (ii) die basiese chemiese en minerale samestelling van lamsvleis; (iii) die chemiese samestelling en verteerbaarheid van lupiene en volvet kanola en die bepaling van alkaloïede in lupiene; (iv) die chemiese samestelling en verteerbaarheid van wintergrane en mielies; (v) die chemiese samestelling en verteerbaarheid van graanhooie, graanstrooie, koringstoppels and lusern-gras/hooi mengsels. Die chemiese samestelling van verskillende tipes wintergrane wat in die Wes-Kaap omgewing van Suid-Afrika geproduseer word, sowel as die chemiese samestelling en verteerbaarheid van wintergraanhooi en –strooi wat geproduseer word in ‘n Mediterreënse reënval omgewing, is ook bepaal. Naby infrarooi refleksie spektrofotometrie was suksesvol in die voorspelling van ru-proteïen (RP) en vet in beide dierspesies, sowel as vir die bepaling van as en droë materiaal (DM) in gevriesdroogde lamsvleis. Akkurate kalibrasies is ook ontwikkel vir sekere minerale (K, P, Na, Mg, Fe en Zn). Kalibrasies ontwikkel vir die chemiese samestellings komponente in lupiene is reg deur die bank akkuraat, sowel as die DM, RP en vet kalibrasies vir volvet kanola. Die alkaloïed kalibrasie het goeie potensiaal getoon, alhoewel meer alkaloïedmonsters benodig word vir ‘n akkurate kalibrasie. Wintergraan kalibrasies was akkuraat vir vet, suurbestande vesels (SBV), in vitro organiese materiaal verteerbaarheid (IVOMV), lisien en metionien. Al die chemiese komponent kalibrasies vir mielies, behalwe die een vir as, was akkuraat vir toekomstige bepalings. Chemiese komponent kalibrasies vir koring stoppels en luserngras/ hooi mengsels het akkuraatheid getoon wat gelyk, of effe beter, is as kalibrasies wat in die literatuur opgeteken is. Kalibrasies ontwikkel vir graanhooie en graanstrooie was nie geskik vir voorspellingsdoeleindes nie. Moontlike redes vir die onakkurate kalibrasies is volledig bespreek. Variasie gevind tussen verskillende tipes wintergrane (2-ry gars, 6-ry gars, hawer, koring en korog) het die behoefte beklemtoon vir ontledings van grane geproduseer onder verskillende omgewingstoestande vir gebruik in dierevoeding. Die chemiese samestelling en verteerbaarheid van wintergraanstrooi en –hooi is ook bepaal. Hierdie waardes verskaf ‘n databasis vir berekening by insluiting van hierdie voergewasse in diererantsoene. Hierdie ondersoek het bewys dat NIRS ‘n suksesvolle en vinnige metode is vir die voorspelling van die chemiese samestelling van volstruis- en lamsvleis en plaaslik geproduseerde voergewasse.

Near infrared reflectance spectroscopy (NIRS) and geostatistical techniques were used to predict diet quality of sub-Saharan African (SSA) livestock, and to create cokriged estimated diet quality maps for cattle across a landscape. Rations of native vegetation were stall-fed to cattle (Bos indicus), sheep (Ovis aries), and goats (Capra hircus) to generate diet-fecal pair data. Trials were conducted in Ethiopia, Kenya, Uganda, Tanzania, and Ghana. Historical data from Ethiopia, Nigeria, and Niger were included. Diet samples were analyzed for crude protein (CP%), and digestible organic matter (DOM%), while feces were scanned for NIR spectra. NIRS equations were developed from data using modified partial least square (MPLS) regression. Coefficients of determination (R2) of CP for cattle, sheep, and goats were 0.92, 0.95, and 0.97, with corresponding standard errors of calibration (SEC) being 0.90, 0.79, and 0.80, respectively. Standard errors of cross validation (SECV) for CP were 1.12%, 1.08%, and 1.03% for cattle, sheep, and goats, respectively. R2 and SEC values for DOM were 0.88, 0.94, 0.94 and 2.82%, 1.68%, and 2.65%, for cattle, sheep, and goats, respectively. Corresponding SECV values for DOM were 3.26%, 2.07%, and 3.30%, respectively. The statistics reported were within the acceptable limits for NIRS calibrations. The results indicate that dietary CP and DOM of free-ranging SSA livestock can be predicted with the same precision as that of conventional wet chemistry methods. The cattle equation was used to predict cattle fecal samples collected, from February to August 2000, from selected households located within the northern Ghana savanna. The predicted CP% and DOM% were used with Normalized Differential Vegetation Index (NDVI) data, and cokriging technique to create diet quality maps for March and July 2000 for the northern Ghana savanna. Cross validation results indicated a moderate capability of cokriging to estimate predicted CP% for March (r2 = 0.687, SEp = 1.736) and July (r2 = 0.513, SEp = 1.558). Cokriged-estimated DOM value for July was above average (r2 = 0.584, SEp = 3.611), while March DOM% estimation was rather poor (r2 = 0.132, SEp = 3.891). The techniques of cokriging and creation of diet quality maps were moderately successful in this study.

Near infrared reflectance spectroscopy (NIRS) and geostatistical techniques were used to predict diet quality of sub-Saharan African (SSA) livestock, and to create cokriged estimated diet quality maps for cattle across a landscape. Rations of native vegetation were stall-fed to cattle (Bos indicus), sheep (Ovis aries), and goats (Capra hircus) to generate diet-fecal pair data. Trials were conducted in Ethiopia, Kenya, Uganda, Tanzania, and Ghana. Historical data from Ethiopia, Nigeria, and Niger were included. Diet samples were analyzed for crude protein (CP%), and digestible organic matter (DOM%), while feces were scanned for NIR spectra. NIRS equations were developed from data using modified partial least square (MPLS) regression. Coefficients of determination (R2) of CP for cattle, sheep, and goats were 0.92, 0.95, and 0.97, with corresponding standard errors of calibration (SEC) being 0.90, 0.79, and 0.80, respectively. Standard errors of cross validation (SECV) for CP were 1.12%, 1.08%, and 1.03% for cattle, sheep, and goats, respectively. R2 and SEC values for DOM were 0.88, 0.94, 0.94 and 2.82%, 1.68%, and 2.65%, for cattle, sheep, and goats, respectively. Corresponding SECV values for DOM were 3.26%, 2.07%, and 3.30%, respectively. The statistics reported were within the acceptable limits for NIRS calibrations. The results indicate that dietary CP and DOM of free-ranging SSA livestock can be predicted with the same precision as that of conventional wet chemistry methods. The cattle equation was used to predict cattle fecal samples collected, from February to August 2000, from selected households located within the northern Ghana savanna. The predicted CP% and DOM% were used with Normalized Differential Vegetation Index (NDVI) data, and cokriging technique to create diet quality maps for March and July 2000 for the northern Ghana savanna. Cross validation results indicated a moderate capability of cokriging to estimate predicted CP% for March (r2 = 0.687, SEp = 1.736) and July (r2 = 0.513, SEp = 1.558). Cokriged-estimated DOM value for July was above average (r2 = 0.584, SEp = 3.611), while March DOM% estimation was rather poor (r2 = 0.132, SEp = 3.891). The techniques of cokriging and creation of diet quality maps were moderately successful in this study.

Le développement de variétés performantes de blé dur (Triticum turgidum durum) doit prendre en compte la corrélation négative entre rendement et teneur en protéines (GPC). Une meilleure compréhension de ce phénomène nécessite une connaissance de l'élaboration des composantes de ces variables. Au cours de cette thèse nous nous sommes focalisés sur l'étude du déterminisme de paramètres foliaires pendant le remplissage du grain (morphologie, résorption d'azote/senescence) ainsi que leurs relations avec les caractéristiques post-récolte (rendement, GPC). La population d'étude est constituée de 282 lignées recombinantes issues d'un croisement demi-diallèle entre quatre lignées élites. Les données proviennent d'expérimentations menées en milieu contrôlé (3 expérimentations) et en plein champ (2 essais).En milieu contrôlé, plusieurs variables (teneur en azote, masse surfacique) ont été prédites par spectrométrie infrarouge à raison de mesures régulières au cours de la période d'intérêt. La résorption d'azote de la dernière feuille a été modélisée pour chaque génotype dont les paramètres ont été analysés. Un lien négatif fort a été établi entre la date d'initiation de la résorption (t0) en temps thermique post-floraison et sa durée et un lien positif entre cette date clé et le poids individuel des grains. A l'échelle de la parcelle, le suivi dynamique de la senescence par la mesure d'évolution d'un indice de végétation, le NDVI (Normalized Difference Vegetation Index) a montré une relation forte entre vitesse d'évolution de la senescence et son ordonnée à l'origine, suggérant que la fin de la senescence était un phénomène très contraint dans les conditions environnementales de plein champ.En absence de stress azoté, l'analyse des 4 géniteurs a montré que des combinaisons linéaires de paramètres foliaires permettaient d'expliquer environ 2/3 des variations de la production en grains d'un épi et de la GPC. En considérant l'ensemble de la population, les effets antagonistes d'une résorption tardive sur la production de grains et la teneur en protéines ont été établis. Une carence en azote appliquée post-floraison provoque une résorption précoce et longue, ce qui semble d'avantage affecter la GPC que le rendement. Une carence en azote appliqué pré-floraison réduit la quantité d'azote disponible dans les feuilles drapeau (et par conséquent leur potentiel photosynthétique) ainsi que le nombre de grains alors que les apports tardifs en azote réalisés dans ce traitement vont retarder la résorption donc augmenter le poids individuel des grains et la GPC. L'analyse génétique en modèle mixte a permis de prendre en compte un apparentement entre lignées, calculé grâce aux pedigrees ou aux marqueurs. Ces deux estimateurs de l'apparentement sont très fortement corrélés ; l'ordonnée à l'origine de la relation (0.3) pouvant être interprétée comme une mesure de l'identité par état de la population de base à partir de laquelle les géniteurs sont issus. Par conséquent, les variances additives issues d'un apparentement marqueurs sont systématiquement supérieures à celles d'un apparentement pedigree. Les valeurs d'héritabilité des variables étudiées caractérisant la morphologie de la feuille drapeau à floraison et des paramètres de résorption d'azote sont du même ordre de grandeur que celles du rendement d'un épi et de la teneur en protéines des grains.En conclusion, nous discutons des stratégies de sélection autour de la corrélation négative rendement/GPC en lien avec la résorption d'azote et la senescence, de l'intérêt de l'utilisation du modèle dit « animal » pour les analyses génétiques et la recherche de QTL. / Performing cultivar development of durum wheat (Triticum turgidum durum) have to take in consideration the negative correlation existing between yield and grain protein content (GPC). A best comprehension of this phenomenon needs the knowledge of these variables elaboration. During this thesis, we focused on the study of foliar parameters determinism during the grain filling (morphology, nitrogen resorption/senescence) and their relations with post-harvest parameters (yield, GPC). The population was formed of 282 recombinant lines coming from a half-diallel cross between 4 elite lines. Data are from experimentations on controlled environment (3 experimentations) and on field (2 experimentations).In controlled environment, various variables (nitrogen content, mass area) were predicted using near-infrared spectroscopy and performing regular measures during the period of interest. Nitrogen resorptions of the last leaf were modeled for each genotype and parameters were analyzed. A strong negative correlation was established between the resorption initiation date (t0) in thermal time post-flowering and its duration and a positive correlation was established between t0 and the grain individual weight. At the plot scale, the dynamic monitoring of senescence through measures of NDVI (Normalized Difference Vegetation Index) evolution showed a strong relation between the senescence evolution rate and its intercept, suggesting the senescence end was a very constraint phenomenon in field.Without nitrogen stress, the analysis of the 4 genitors indicated that linear combinations of foliar parameters could explain around 2/3 of one-spike grain production and GPC variations. Considering the entire population, the antagonist effects of a late resorption on grain production and on the GPC were established. A post-flowering nitrogen stress causes an early and long resorption which seems to affect more GPC than yield. A pre-flowering nitrogen stress reduces nitrogen quantity available in flag leaves (and consequently their photosynthetic potential) and the grain number whereas late nitrogen inputs of this environment delay resorption and raise grain individual weight and GPC.The genetic analysis in mixed model allowed taking into account relatedness among lines, calculated with pedigrees or markers. Those 2 relatedness estimators are strongly correlated; the regression intercept (0.3) can be interpreted as an identity-by-state measure of the base population from which genitors are derived. Consequently, additive variances from a marker-relatedness model are always superior to additive variances form a pedigree-relatedness model. Heritability values of the study variables (flag leaf morphology and nitrogen resorption parameters) have the same order of magnitude than those of one-spike yield and GPC.Field experimentations allowed highlighting the flag leaf weight as a contributor organ to yield and GPC. Nitrogen balance showed a link between post-flowering nitrogen fluxes and nitrogen available at flowering. Genotype-phenotype association's research was realized through a simple-marker analysis for all the experimentations and a Composite Interval Mapping analysis only for data obtained in greenhouses. A stable QTL was detected on the 3 controlled environments for t0. QTL comparison on controlled environment QTL and field QTL highlighted various area containing QTL on certain chromosomes: an area of foliar nitrogen content at flowering QTL on the 1A, an area of GPC QTL, Thousand Kernel Weight (TKW) QTL and grain number QTL on the 2A, an area of foliar morphology QTL on the 2B, an area of TKW QTL on the 3B and an area of senescence variables QTL on the 7B.In conclusion, we discuss about breeding strategies around the negative correlation yield/GPC in relations with nitrogen resorption and senescence and about the interest to use the “animal” model for genetic analysis and QTL research.

Les sols constituent le premier réservoirterrestre de carbone organique et jouent ainsi un rôleclé pour limiter le réchauffement climatique. Les solsurbains représentent 3% du territoire mondial etl’urbanisation est la première cause de changementd’affectation des sols. L’augmentation rapide dessurfaces artificialisées a entraîné un intérêt croissantquant à la capacité des sols urbains à stocker ducarbone. Les travaux de thèse ont visé à comprendrela contribution des sols urbains au stock global decarbone organique et à proposer une méthodestandardisée pour son suivi. Les recherches ont aussiporté sur l’étude de la stabilité du carbone organiquedes sols urbains et la modélisation de la dynamique dece carbone. Une base de données a été construite àpartir de données disponibles au niveau national, puisde mesures supplémentaires acquises dans trois villes françaises.Le stock de carbone des sols ouverts est similaireentre les villes, et équivalent voire supérieur enprofondeur, à celui des sols forestiers environnants.Ce stock dépend plus particulièrement du mode degestion des espaces verts urbains, et de l’histoire dusite. Ainsi, les sols urbains ouverts sont caractériséspar une forte proportion de matières organiqueslabiles sur 0-44 cm de profondeur. Au contraire, lessols scellés présentent des stocks de carbone trèsfaibles. Ils sont caractérisés par une forte proportionde matières organiques stables dont l’évolution(stockage ou minéralisation) dépend de l’état dedormance microbienne. Un modèle conceptuel de ladynamiq / Soils are the largest terrestrial pool oforganic carbon and thus play a key role in mitigatingclimate change. The urban soils account for 3% of theworld’s territory and urbanization is currently theprimary cause of land use change. The increase ofartificial areas have led to a growing interest in theurban soil ability to store organic carbon. This workaimed to understand the contribution of urban soils tothe global organic carbon stock and to propose astandardized method for its monitoring. The researchalso focused on studying the stability of organic carbonin urban soils and modeling its dynamics. A databasewas built using data available at the French territorylevel as well as using additional measurements acquired in three French cities.The organic carbon stock in urban open soils aresimilar between cities, and equivalent, or even higherin depth, than that of surrounding forest soils. Thestock in open soils is particularly dependent upon themanagement methods of the urban green spaces,and on the specific site history. Thus, open urban soilsare characterized by a high proportion of labileorganic matter at 0-44 cm depth. Conversely, sealedsoils have very low carbon stocks. They arecharacterized by a high proportion of stable organicmatter whose evolution (storage or mineralization)depends on the dormant state of the microbialcommunities. A conceptual model of carbon dynamicsfor these two soil types has been developed. Finally,recommendations for optimizing carbon monitoringand urban soil management have been proposed

No description available.

To produce high quality paper, lignin should be removed from the pulp. Quantification of lignin concentrations using standard wet chemistry is accurate but time consuming and costly, thus not appropriate for a large number of samples. The ability of hyperspectral remote sensing to predict foliar lignin concentrations could be utilized to estimate wood lignin concentrations if meaningful relationships between wood and foliar chemistry are established. LAI (leaf area index) is a useful parameter that is incorporated into physiological models in forest assessment. Measuring LAI over vast areas is labour intensive and expensive; therefore, LAI has been correlated to vegetation indices using remote sensing. Broadband indices use average spectral information over broad bandwidths; therefore details on the characteristics of the forest canopy are compromised and averaged. Moreover, the broadband indices are known to be highly affected by soil background at low vegetation cover. The aim of this study is to determine foliar and wood lignin concentrations of Eucalyptus clones using hyperspectral lignin indices, and to estimate LAI of Eucalyptus clones from narrowband vegetation indices in Zululand, South Africa Twelve Eucalyptus compartments of ages between 6 and 9 years were selected and 5 trees were randomly sampled from each compartment. A Hyperion image was acquired within ten days of field sampling, SI and LAI measurements. Leaf samples were analyzed in the laboratory using the Klason method as per Tappi standards (Tappi, 1996-1997). Wood samples were analyzed for lignin concentrations using a NIRS (Near Infrared Spectroscopy) instrument. The results showed that there is no general model for predicting wood lignin concentrations from foliar lignin concentrations in Eucalyptus clones of ages between 6 and 9 years. Regression analysis performed for individual compartments and on compartments grouped according to age and SI showed that the relationship between wood and foliar lignin concentration is site and age specific. A Hyperion image was georeferenced and atmospherically corrected using ENVI FLAASH 4.2. The equation to calculate lignin indices for this study was: L1R= ~n5il: A'''''y . 1750 AI680 The relationship between the lignin index and laboratory-measured foliar lignin was significant with R2 = 0.79. This relationship was used to calculate imagepredicted foliar lignin concentrations. Firstly, the compartment specific equations were used to calculate predicted wood lignin concentrations from predicted foliar lignin concentrations. The relationship between the laboratorymeasured wood lignin concentrations and predicted wood lignin concentrations was significant with R2 = 0.91. Secondly, the age and site-specific equations were used to convert foliar lignin concentration to wood lignin concentrations. The wood lignin concentrations predicted from these equations were then compared to the laboratory-measured wood lignin concentrations using linear regression and the R2 was 0.79 with a p-value lower than 0.001. Two bands were used to calculate nine vegetation indices; one band from the near infrared (NIR) region and the other from the short wave infrared (SWIR). Correlations between the Vis and the LAI measurements were generated and . then evaluated to determine the most effective VI for estimating LAI of Eucalyptus plantations. All the results obtained were significant but the NU and MNU showed possible problems of saturation. The MNDVI*SR and SAVI*SR produced the most significant relationships with LAI with R2 values of 0.899 and 0.897 respectively. The standard error for both correlations was very low, at 0.080, and the p-value of 0.001. It was concluded that the Eucalyptus wood lignin concentrations can be predicted using hyperspectral remote sensing, hence wood and foliar lignin concentrations can be fairly accurately mapped across compartments. LAI significantly correlated to eight of the nine selected vegetation indices. Seven Vis are more suitable for LAI estimations in the Eucalyptus plantations in Zululand. The NU and MNU can only be used for LAI estimations in arid or semi-arid areas. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.