Pacific silver fir (Abies amabilis (Dougl. ex Loud.) Forbes) is an important timber crop species in coastal forests of B.C. Its range extends from sea-level to almost timberline, and from the hypermaritime region on the west coast of Vancouver Island to the subcontinental region on the leeward side of the Coast Mountains. With this relatively wide climatic amplitude, a large variability in the height growth pattern of Pacific silver fir can be expected, since climate is considered to be the most influential determinant of the trajectory of height over age of forest trees. This variability, however, is not reflected in the height growth curves and site index tables used to estimate Pacific silver fir site index, since the curves and tables were developed from low-elevation stands on Vancouver Island. Consequently, when these curves and tables are applied to high-elevation or submaritime stands, we get biased estimates of site index. Accurate estimates of site index are necessary for accurate yield predictions. Furthermore, they are essential for making rational decisions about whether to cut the forest in situations where potential tree growth is marginal, such as in high-elevation forests.

In BC, it is required that harvested areas be regenerated with a mixture of tree species whenever appropriate to the site. This policy is based upon the assumption that increases in stand productivity, reliability, and/or biodiversity can be achieved in mixed-species stands. However, the knowledge justifying this policy is at best incomplete. Differences in forest productivity of mixed-species stands have been attributed mostly to competition. However, an increasing number of studies are providing evidence to support alternate theories, in which positive plant interactions play a major role. Positive plant interactions are divided into two components: (i) competitive reduction through structural and physiological differences in above and below ground structures, and (ii) facilitation through any positive effect on the growing environment of one plant species by another. These theories have yet to be tested in forest ecosystems. The objectives of this study, with respect to naturally established, unmanaged, second-growth stands of western hemlock (Hw) (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Cw) (Thuja plicata Donn ex D. Don in Lamb.), and their mixtures, were: (1) to review the mechanisms of positive plant interactions and their potential to occur in these mixtures, and (2) to compare the productivity of these three stand types, using relative and absolute yield.

Western larch (Larix occidentalis Nutt.) is a locally important species in the Nelson Forest Region, and to a lesser extent, in the Kamloops Forest Region. Its range extends from west of the Rockies to Okanagan Lake, and north to Salmon Arm, in the IDF, ICH, MS, and ESSF biogeoclimatic zones. Prior to this study, the site index curves developed for western larch in western Montana were used to model height and estimate site index in British Columbia. It has been suggested that these curves may not adequately reflect the height growth patterns of western larch in BC. Differences could arise from genetics, different methods of selecting sample trees, or climatic differences. The objective of this project was to produce accurate height growth models for western larch in BC.

Accurate and reliable predictions of site index (height of dominant trees at a reference age, usually 50 years at breast-height) for timber crop species is essential for silvicultural site-specific decision making. Site index can be predicted from site quality once the relationship between site index and site quality has been quantified. Site quality is defined as the sum of all environmental factors affecting the biotic community, such as the factors directly influencing the growth of vascular plants (light, heat, soil moisture, soil nutrients, and soil aeration). Since these factors vary greatly in time, indirect estimates of site quality have widely been used as predictors for site index in various multiple regression models. Trembling aspen (Populus tremuloides Michx.) is the most widely distributed broadleaf species in British Columbia, especially in the Boreal White and Black Spruce (BWBS) biogeoclimatic zone. Growing this species for sustainable timber production requires a good understanding of its productivity attributes and accurate predictions of its growth. This extension note presents (1) relationships between trembling aspen site index and some indirect measures of site quality, and (2) site index prediction models using the indirect measures of site quality as predictors.

Height growth models of coastal low- and mid-elevation Pacific silver fir, low-elevation white spruce, and low- and midelevation lodgepole pine have been used for predicting productivity of subalpine fir, Engelmann spruce, and lodgepole pine, respectively. These models, however, are biased in predicting height growth of high-elevation subalpine fir, Engelmann spruce, and lodgepole pine. To improve this situation, 329 sample plots (165 for subalpine fir, 90 for Engelmann spruce, and 74 for lodgepole pine) were located throughout the Engelmann Spruce-Subalpine Fir (ESSF) zone. Stem analysis was carried out on three dominant trees in each 0.04 ha sample plot. For each study species, a height growth model was developed on the data from two-thirds of the sample plots using the conditioned Chapman-Richards’ function; the model was validated using the remaining one-third of the sample plots.

A simplified process-based model simulating growth and water use in forest plantations was utilised to predict the growth of Pinus elliottii in South African forest plantations. The model is called 3-PG (Physiological Principles in Predicting Growth) and predicted the growth of trees by simulating physiological processes that determine growth and water use, and the way trees are affected by the physical conditions to which they are subjected, and with which they react. Pinus elliottii growth data recorded in 301 sample stands around South Africa were sourced from forestry companies. A selection procedure reduced the number of stands to 44, where 32 were used to parameterise 3-PG and 12 were reserved for testing the final model parameters. This was accomplished by matching model output to observed data. All stand simulations were initialised at age four years and continued to the maximum age of recorded growth. A provisional set of parameter values provided a good fit to most stands and minor adjustments of the specific leaf area (σ), which was assigned a value of 5 m2.kg-1, were made, bringing about an improved fit. The predictions of mean DBH, Height, and TPH were relatively good, achieving R2 of 0.8036, 0.8975, and 0.661 respectively, while predictions of stem volumes were worse (R2 =0.5922, n=32). The 3-PG model over-predicted DBH in 20 stands, while modelled volume predictions improved substantially in thinned stands (R2 =0.8582, n=14) compared to unthinned stands (R2 =0.3456, n=18). The height predictions were generally good producing an R2 =0.8975. The final set of 3-PG parameter values was then validated against growth data from the 12 independent stands. The predictions of mean DBH, Height, and TPH were relatively good, achieving R2 of 0.8467, 0.7649, and 0.9916 respectively, while predictions of stem volumes were worse (R2 =0.5766, n=12). The results of this study demonstrated the potential for 3-PG to respond to many growth factors and to predict growth and water use by trees with encouraging realism. Patterns of changing leaf area index (L) over time, responses to drought, and annual evaporation patterns all look realistic. Consequently, 3-PG is judged to have potential as a strategic forestry tool. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

Exotic pine plantations are a major landuse within the coastal lowlands of southeast Queensland, extending from close to the shoreline to the hinterland ranges. These plantations are within a sub-tropical climatic zone, and in most years, the summers are appreciably wetter than the winters. This terrain, in general, has been highly weathered and the soils are poor in nutrients. Environmental factors such as the climate, topography and weathering profile (including soil) are found to be important controls on vadose zone hydrology, which, in turn, has a great impact on tree growth and consequently on the design of management practices. This research project takes a holistic approach to investigate the influence of these environmental factors at different scales, and is designed to fulfil the following objectives: (1) To build a spatial model of forest productivity for the entire Tuan Toolara State Forest (TTSF), southeast Queensland, by analysing the spatial patterns of many environmental variables that may have controls on soil water distribution. (2) To determine how some of these environmental factors are responsible for the development of water-logging and soil salinisation by examining in detail an area of low site index that is severely affected by these two processes. (3) To develop a model to assess the risks of water-logging spatially and temporally. A multiple regression model was constructed to predict the forest productivity (measured by the value of site index, the average dominant tree height at 25 years of age). The independent variables were derived from a digital elevation model (elevation, slope, curvature, hillshade, flow accumulation and distance to streams), γ-ray spectrometry (potassium, thorium and uranium), and interpolated rainfall. The model explained up to 60% of the variance in the site indices and produced predictive maps of site index for two species: P. elliottii Engelm. and Queensland hybrid, a P. elliottii × P. caribaea Morelet hybrid. The model also identified the lowest site index area at the northern Tuan State Forest (NTSF), likely due to a greater risk of water-logging and salinisation. The NTSF area is of low relief and, therefore, the focus has been on the vertical controls of deep weathering profile. The methodology included setting up a network of groundwater bores screened at different depths within the weathering profile, characterising the profile (mineralogy, EC, and pH) and the groundwaters within it (water levels, physico-chemical parameters, major and minor ions). It is found that water-logging is caused by perched groundwater formed on top of the ferricrete or mottled saprolite after prolonged rainfall. Localised salinisation is related to the discharge of brackish groundwater occurring within the mottled saprolite. The deep aquifer within the coarse saprolite is fresh and not responsible for salinisation, a situation that differs from many other settings in Australia. The ability of using the Soil and Water Assessment Tool (SWAT) computer model to simulate soil water balance and to assess the risks of water-logging was tested in a selected catchment in the TTSF. The model successfully simulated stream flow at 2 weirs for a period of 6 years; the achieved R2 were 0.752 and 0.858, respectively. Long-term simulation for a 30-year period showed that there are pronounced seasonal patterns in rainfall and evapotranspiration as well as in soil water. For mature plantation with slopes of 3-15%, the mean annual duration of water-logging ranged from 161 days in the humus podzols, to 110 days in the gleyed podzolic, and to 90 days in the yellow podzolics. The outcomes of this research suggest that forest management can be strongly supported by understanding the impacts of these environmental factors (e.g. climate, topography and weathering profile) on vadose zone hydrological processes; the selection of optimum approach will depend on the research objective or purpose. The models and analytical tools that were developed or tested here have the potential to be successfully applied elsewhere if the input data are available.

There are considerable expenditures by government and private forest industry to enhance the growth of forests and reduce time required for crop rotation. The effectiveness of some of these treatments is dependent on site productivity. In addition, as responsible stewards of the forest resource and habitat, it is important that the state of forests are actively monitored, especially in the face of a changing climate and increased rates of disturbance. This dissertation reports on the development of a method for estimating and mapping forest productivity. The Shawnigan Lake thinning and fertilization forest installation, established in 1971 by CFS, was selected as the study site largely for its rich mensuration history. Square treatment plots were 0.04ha in area and included two thinning levels (1/3 & 2/3 of the basal area), two fertilization treatments (224kg & 448kg N/ha) with repeated fertilizations and macronutrient experiments (S, P) and control plots. A sample of plots was selected for high precision ground based lidar reference surveys. In September of 2012 a multi-sensor airborne survey of SLP was conducted that collected high-density lidar (up to ~70pnts/m2) and VNIR imaging spectroscopy. A thorough empirical radiometric calibration was conducted in addition to a spatial calibration at the Victoria International Airport. A combination of area based height percentile, point density ratios and statistical moments with individual lidar tree metrics including height distribution and proximity metrics were generated. Topographic metrics were also generated from the lidar ground classified point cloud. A library of spectral indices was computed from the imaging spectrometer data, with an emphasis on those indices known to be associated with vegetation health. These metrics were summarized to the plot level for a coarse scale regression analysis. A control survey and ground based lidar was used to facilitate an individual tree based fine scale of analysis, where reference data could unambiguously be matched to airborne collected data through the projected positions. Regression analysis was conducted applying the best subset regression with exhaustive feature selection search criteria and included a critical evaluation of the resulting selected features. Models were investigated considering the data source and in combination, that is, lidar metrics were considered independent of spectroscopy as well as the converse, and lidar metrics in combination with spectral metrics. The contribution of this study is the revelation that existing area based point cloud metrics are highly correlated, potentially noisy and sensitive to variations in point density, resulting in unstable feature selection and coefficients in model building. The approach offered as an alternative is the gridded lidar treetops method, which is evidently lacking within the literature and which this study overwhelmingly advocates. Additionally, the breadth and diversity of metrics assessed, the size and quality of the reference data applied, and the fine spatial scale of analysis are unique within the research area. This study also contributes to the knowledge base, in that, productivity can be estimated by remote sensing technologies. The use of gridded generalizations of the individual tree approach reduced estimation errors for both structural and productivity attributes. At the plot-level, crown structure and crown health features best estimated productivity. This study emphasizes the dangers of empirical modeling; at the even-aged SLP installation, growth is strongly tied to structure and the extrapolation to other sites is expected to provide biased values. It is my perspective that physical lidar structural models of the dominant and co-dominant crown classes be used to augment spatially explicit tree and stand growth models. In addition, direct measures should be obtained by multi-temporal lidar surveys or as an alternative photogrammetric point clouds after an initial lidar survey to quantify growth and aid in calibrating growth models. / Graduate

O 3-PG (Physiological Principles in Predicting Growth) é o modelo ecofisiológico mais difundido no setor florestal para a predição de crescimento de florestas. Este modelo estima o crescimento florestal com base na radiação fotossinteticamente ativa absorvida pelo dossel, convertida em carboidratos, e alocada nos compartimentos da floresta (folhas, tronco, galhos e raízes), fundamentados na dinâmica dos processos biológicos e suas interações com o clima e solo. No entanto, após quase 15 anos de existência do 3-PG unido a evolução em pesquisa florestal, é possível detectar alguns pontos no modelo com potencialidade para aprimoramento. O objetivo geral desta tese foi aprimorar o modelo 3-PG e aplicá-lo no zoneamento da produtividade em florestas de Eucalyptus plantadas no nordeste do estado de São Paulo. Os objetivos específicos foram: i) aprimorar o modelo para retenção máxima de água no solo; ii) para queda de folhedo; iii) calibrar e validar o modelo 3-PG usando os pares de parcelas gêmeas; iv) determinar o modificador de fertilidade (FR) do 3-PG usando análise química do solo; v) zonear a produtividade real estimada do Eucalyptus no nordeste do estado do São Paulo; vi) determinar os fatores de restrição da produtividade nestas áreas. Para tanto, utilizou-se de dois projetos de pesquisas instalados na empresa International Paper do Brasil: projeto BEPP (Brasil Eucalyptus Produtividade Potencial) e projeto Parcelas Gêmeas de Inventário. O projeto BEPP foi utilizado para o aprimoramento do modelo em relação à retenção de água e queda de folhedo. Para tanto, utilizou-se de dois tratamentos: o tratamento fertilizado irrigado e o tratamento controle (fertilização tradicional sem irrigação). A quantidade máxima de água no solo adotada pelo modelo, antes considerada como um valor constante, passou a variar segundo a dinâmica de crescimento e exploração do sistema radicular. Esta modificação melhorou a estimativa de biomassa do tronco. No aprimoramento do modelo para a queda de folhedo, ajustou-se quatro modelos: linear; logístico; não lineares e modelo combinado. Todos proporcionaram melhores estimativas da taxa de queda de folhedo do que a função atualmente adotado pelo 3-PG com destaque para o modelo combinado, o qual representou duas fases da queda de folhedo: antes e após o fechamento do dossel. Usando os 113 pares de parcelas gêmeas, verificou-se que 63% responderam à fertilização após 48 meses de instalação do experimento, com ganho médio de 12% em produtividade. Com estas parcelas gêmeas foi possível calibrar e validar o modelo 3-PG para a produtividade atingível e real, com adequada precisão. O FR foi correlacionado à somas de bases do solo (Ca, Mg e K), as quais explicaram as maiores respostas à fertilização, sendo possível determinar uma equação para este modificador. Após a calibração e validação e adequações do modelo foi possível zonear a produtividade real do nordeste do estado de São Paulo. O déficit de pressão de vapor e água no solo foram os fatores que mais limitaram o crescimento do Eucalyptus nesta área. / The 3-PG (Physiological Principles in Predicting Growth,) is the most widespread ecophysiological model in the forest sector to predict the forest growth. It is driven by intercepted radiation with the maximum canopy quantum efficiency, which is limited by the temperature, vapour pressure deficit, available soil water, stand age and site fertility, assimilating the carbon into the forest; supported by physical and ecophysiological processes. However, after almost 15 years of development and use, associated by new scientific knowledge in forest research, some improvement in this model can be done, such as: soil water content and litterfall rate. The objectives of this thesis were improve the 3-PG model and zone the real productivity of Eucalyptus plantation in northeast of São Paulo State. The specifics objectives were: i) improve the 3-PG model regarding water soil content; ii) regarding litterfall; iii) calibrate and validate the 3-PG model using the twin-plot experimental design; iv) determine the fertilization modifier (FR) using soil chemical analysis; v) zoning the real productivity for Eucalyptus plantation in northeast of São Paulo State; and vi) determine the main growth constraints. Aiming these objectives, two main research projects were used: BEPP project (Brasil Eucalyptus Produtividade Potencial) and the Twin-plot of inventory. The BEPP was used to improve the 3-PG model for water soil content and litterfall. Two treatments were used: fertilized plus rainfed and extra fertilized plus irrigation. The water soil content had a constant value and was replaced by a dynamic value, changing with root growth and exploratiion depth with the age. This modification improved the stem biomass production estimatives by the model. For the litterfall improvement, 4 functions were fitted (linear, logistic, non linear and mixed). All of those had better performance in estimating the litter fall than the original 3-PG equation, highlighting the mixed model that could represent before and after canopy closure. Using 113 pairs of twin-plots, 63% of those responded the extra fertilization after 48 months, the production gain was 12%. The twin-plots were used to calibrate and validate the 3-PG model for attainable and real productivity resulted in adequated accuracy for stem biomass estimation. The FR could be associated with chemical analysis, and sum of bases (Ca, Mg and K) were used to fit an FR equation. After calibration and valitadation of the 3-PG model, were possible to zone the real productivity in northeast of São Paulo; the two main constraints of productivity for those area were vapour pressure deficit and soil water.

The planting of large areas with exotic species is a consequence of the evolution of an entire industrial structure; it aims to meet the demand for forest products. The use of these species requires knowledge on the techniques of soil preparation, fertilization, weed competition, and residue management and harvest intensity, among others. The objective of this study was to evaluate aspects of biogeochemical cycling of nutrients in Eucalyptus dunnii established in a watershed located in the Pampa biome, municipality of Alegrete/RS in area belonging to Stora Enso S.A. The following parameters were evaluated monthly: the rainfall, within and outside the forest stand, litterfall deposition, the total biomass and the output of nutrients by runoff from the watershed. Precipitation was sampling through twelve collectors of internal precipitation, twelve collectors solution resulting from stemflow and three external collectors. The runoff was sampling with aid of container for water collection of 500 ml, made in the spillway of a flume. Sampling of litterfall was obtained through sixteen collectors of 0.5 m² of floor area, to evaluate the fractions of leaves and miscellany, in addition, sixteen areas of collecting thick branches. The determination of biomass occurred after the cutting of twelve trees, considered representative of four diameter classes, with the excavation of their respective roots. The rainfall within the forest stand, litterfall deposition and biomass were evaluating in four installments. The rainfall, biomass production and litterfall and the output of ecosystem nutrients by runoff were evaluating for quantity, the concentration of elements and the contribution thereof. It was founded that the total rainfall was 1385.28 mm yr-1 corresponding to the average of 2012 and 2013 value and the internal precipitation was 91.4% and the stemflow was 1.3%, where 7.61% were intercepting by the canopy. The annual effective precipitation was 1242.69 mm, corresponding to approximately 90% of the local rainfall. It has been found that the interaction of rain with the results in the leaching of surface of the tissue, increasing in 421% the concentration of K, 24.0% the concentration of Ca and 185% the concentration of Mg. In the internal precipitation, the order of predominance was Cl > K+ > SO4- > Ca²+ > Mg²+ and the stemflow, in the order of predominance was K+ > Cl > Mg²+ > Ca²+ > SO4- . The total biomass of the stand was 67.49 Mg ha-1, with a decreasing sequence of accumulation of biomass: wood stem > root > trunk bark > branches > leaves. The total quantity of nutrients in kg ha-1, was: 211.51 of N; 22.12 of P; 199,88 of K; 39,70 of Ca; 86.42 of Mg and 25.05 of S; and the micronutrients in g ha-1, was 562.57 of B; 401.46 of Cu; 9913.28 of Fe; 31877.82 of Mn and 766.96 of Zn. There was accumulation of Mn in biomass components, in addition that the highest concentrations of nutrients are in the tissues of the canopy. The average litterfall production was 7.0 Mg ha-1 yr-1. The forming material of the litterfall consists of sheets, contributing the majority of the deposition (64.3%) followed by twigs (17.5%), thick branches (10.2%) and miscellaneous (7.9%), being Ca the most representative element into leaves, twigs and boughs, presenting only in the miscellaneous fraction, less than N. The P and S elements reported the lowest concentrations. The total transfer of macronutrients was 163.0 kg ha-1 and micronutrients was 9.7 kg ha-1, the macronutrient levels found in litterfall followed the descending order Ca > N > K > Mg > S > P and micronutrient followed the descending order of Mn > Fe > B > Zn > Cu. Three harvesting systems were simulated, completely tree above the ground; wooden trunk + bark and stem wood only. In all simulations, the balances were positive. The total retention of crop residues on the forest site can provide a higher percentage of return of nutrients to the soil. The weight of the harvest Eucalyptus dunnii Maiden, planted in sandy soil and low fertility affected, albeit positively, differently biogeochemical cycling of nutrients / O plantio de grandes áreas com espécies exóticas é uma consequência da evolução de toda uma estrutura industrial, que tem como objetivo atender a demanda por produtos florestais. O uso destas espécies exige conhecimentos quanto às técnicas de preparo de solo, adubação, mato-competição, além de manejo de resíduos e intensidade de colheita, dentre outras. O objetivo deste trabalho foi avaliar aspectos da ciclagem biogeoquímica de nutrientes em um povoamento de Eucalyptus dunnii, estabelecido em uma microbacia hidrográfica localizada no bioma Pampa, município de Alegrete/RS, em área pertencente à empresa Stora Enso S.A. Os seguintes parâmetros foram avaliados mensalmente: a precipitação pluviométrica, dentro e fora do povoamento, a deposição de serapilheira, biomassa total, além da saída de nutrientes por deflúvio da microbacia hidrográfica. A precipitação foi amostrada por meio de doze coletores de precipitação interna, doze coletores de solução decorrente do escorrimento pelo tronco e por três coletores externos ao plantio florestal. O deflúvio foi amostrado com auxílio de recipientes de 500 ml para coleta de água, realizada no vertedouro com uma calha tipo flume. A amostragem da serapilheira foi obtida por meio de dezesseis coletores de 0,5 m² de área útil, para avaliação das frações folhas e miscelânea, além de dezesseis parcelas de coleta de galhos grossos. A determinação de biomassa ocorreu a partir da derrubada de doze árvores, consideradas representativas de quatro classes de diâmetro, junto da escavação das respectivas raízes. A precipitação dentro do povoamento, a deposição de serapilheira e a biomassa foram avaliadas em quatro parcelas. A precipitação, a produção de biomassa e de serapilheira e a saída de nutrientes do ecossistema por deflúvio, foram avaliadas quanto à quantidade, a concentração de elementos e ao aporte dos mesmos. Constatou-se que a precipitação total foi de 1.385,28 mm ano-1, valor correspondente à média de 2012 e 2013, já a precipitação interna foi 91,4% e o escorrimento pelo tronco foi 1,3%, sendo que 7,61% foram interceptados pelo dossel. A precipitação efetiva anual foi 1.242,69 mm, correspondendo a aproximadamente 90% da precipitação pluviométrica local. Verificou-se que a interação da chuva com as copas possibilitou a lixiviação de metabólitos presentes na poeira atmosférica depositada na superfície dos tecidos, aumentando em 421% a concentração de K, em 24,0% à concentração de Ca e em 185% a concentração de Mg. Na precipitação interna, a ordem de predominância foi Cl- > K+ > SO4- > Ca²+ > Mg²+ e para o escorrimento pelo tronco a ordem de predominância foi K+ > Cl- > Mg²+ > Ca²+ > SO4-. A biomassa total do povoamento foi de foi de 67,49 Mg ha-1, com sequência decrescente de acúmulo de biomassa: madeira do tronco > raiz > casca do tronco > galhos > folhas. A quantidade total de macronutrientes, em kg ha-1, foi de: 211,51 de N; 22,12 de P; 199,88 de K; 39,70 de Ca; 86,42 de Mg e 25,05 de S; e a de micronutrientes, em g ha-1, foi de 562,57 de B; 401,46 de Cu; 9.913,28 de Fe; 31.877,82 de Mn e 766,96 de Zn. Houve acúmulo de Mn nos componentes da biomassa, além de que as maiores concentrações de nutrientes estão nos tecidos das copas. No entanto, a maior quantidade de biomassa encontra-se na madeira. A produção de serapilheira média foi de 7,0 Mg ha-1 ano-1. O material formador da serapilheira é constituído por folhas, contribuindo com a maior parte da deposição (64,3%) seguida por galhos finos (17,5%), ramos grossos (10,2%) e miscelânea (7,9%), sendo Ca o elemento mais representativo nas frações folhas, galhos finos e galhos grossos, apresentando-se apenas na fração miscelânea, inferior ao N. Os elementos P e S apresentaram as menores concentrações. A transferência total de macronutrientes foi de 163,00 kg ha-1 e de micronutrientes foi 9,73 kg ha-1, teores de macronutrientes encontrados na serapilheira apresentaram a seguinte ordem Ca > N > K > Mg > S > P e os teores de micronutrientes seguiram a ordem decrescente de Mn > Fe > B > Zn > Cu. Foram simulados três sistemas de colheita: árvore inteira; madeira do tronco+casca e somente madeira do tronco. Em todas as simulações os saldos foram positivos. A permanência total dos resíduos da colheita no sítio propiciou um maior percentual de retorno de macronutrientes ao solo. O peso da colheita do Eucalyptus dunnii Maiden, plantado em solo arenoso e de baixa fertilidade natural afetou, ainda que positivamente, de forma diferenciada a ciclagem biogeoquímica dos nutrientes.