Les capacités de réserve cérébrale représentent les capacités de résilience du cerveau face à différents processus lésionnels comme ceux induit par la maladie d’Alzheimer (MA). Plusieurs hypothèses ont été proposées afin d’expliquer ce mécanisme. Les deux concepts les plus validés sont celui de la réserve cérébrale faisant référence au substrat cérébral et la réserve cognitive faisant référence à la fonctionnalité cérébrale. Les données épidémiologiques puis d’imagerie ont permis d’identifier des expériences de vie associées à de meilleures capacités de réserve cérébrale. Le niveau d’études, la profession exercée et la pratique d’activités de loisirs sont ainsi des indicateurs du niveau potentiel de capacités de réserve d’un sujet. L’objectif général de ce travail de thèse avait pour objectif de mieux caractériser les relations entre ces indicateurs et les capacités de réserve cérébrale. Tout d’abord, nous nous sommes intéressés à la relation entre ces expériences de vie et le substrat cérébral à partir de données d’imagerie recueillies au cours du suivi de la cohorte des 3 cités à Bordeaux. Nous avons ainsi montré que seul le niveau d’éducation était associé à des différences de volume de substance grise et de substance blanche entre les sujets de haut et bas niveau d’études. Par ailleurs, les sujets de haut niveau d’études présentaient une progression moindre en hypersignaux de substance blanche au cours du suivi de la cohorte des 3 cités indépendamment de la présence de facteurs de risque cardiovasculaires. Le niveau d’étude semble avoir une place non négligeable dans la constitution des capacités de réserve cérébrale et aussi bien dans la réserve cognitive que la réserve cérébrale. Ceci explique le rôle protecteur du niveau d’études vis à vis du risque de démence. Dans un 3ème travail, nous nous sommes servis de cette relation particulière entre le niveau d’études et la démence afin d’illustrer comment un facteur social peut être un facteur de maladie chronique liée à l’âge et comment en le modifiant, on peut éventuellement modifier la survenue de cette maladie. Enfin, nous nous sommes intéressés à la relation entre la pratique d’activités de loisirs au cours de la retraite et le risque de démence à partir des données de la cohorte Paquid. La pratique de jeux de société est associée à un moindre risque de démence mais le lien fort avec la cognition ne permet pas d’éliminer une causalité inverse. Cependant, un engagement plus important dans la pratique d’activités de loisirs au cours de la retraite est associé à un risque moindre de démence équivalent à des sujets ayant toujours pratiqué des activités. Des essais d’intervention permettraient de confirmer l’effet bénéfique de la pratique d’activités de loisirs sur la cognition et le risque de démence. / The brain reserve capacities represent the resilience of the brain to cope against different pathological processes such as Alzheimer's disease (AD). Several hypotheses have been proposed to explain this mechanism. The two most validated concepts are the brain reserve referring to brain volume and cognitive reserve referring to brain function. Epidemiological and imaging data helped identify life experiences associated with better brain reserve capacities. Thus, the education, occupation and practice of leisure activities are recognized as proxies of the brain reserve capacities. The main objective of this thesis aimed to better characterize the relationship between these proxies and the brain reserve capacities. First, from brain imaging data collected during follow-up of the three cities cohort of Bordeaux, we examined the relationship between life experiences and brain volume. Only the education was associated with differences in gray and white matter volume. In addition, highly educated subjects had a smaller progression of white matter hyperintensities during the follow-up of this cohort independently of the presence of cardiovascular risk factors. Education seems to have a significant role in the formation of brain reserve capacities in both cognitive reserve and brain reserve. This explains the protective role of educational level against dementia. In a third work, we used this particular relationship between educational level and dementia to illustrate how a social factor can be a factor of a chronic disease related to aging and can modify the occurrence of this disease. Finally, we are interested in the relationship between the practice of leisure activities during retirement and the risk of dementia from data of Paquid study. The practice of playing board games is associated with a lower risk of dementia, but the strong link with cognition not eliminates reverse causality. However, a greater engagement in the practice of leisure activities in retirement is associated with a lower risk of dementia similar to subjects who always practiced activities. Intervention trials could confirm the beneficial effect of the practice of leisure activities on cognition and dementia risk.

Master of Science / Department of Biological and Agricultural Engineering / Donghai Wang / Biomass torrefaction is an important preprocessing step in improving biomass quality, specifically in terms of physical properties and chemical composition. The objective of this research was to study effects of torrefaction as a pretreatment method on chemical and elemental compositions and thermal properties of Conservation Reserve Program (CRP) biomass. Most CRP grasslands are a mixture of native grasses, and in the state of Kansas, species including indiangrass, big bluestem, little bluestem, sideoats grama, and switchgrass comprise a majority of CRP grounds. Pure forms of big bluestem biomass were analyzed and compared with a mixture of the species that make up CRP lands. Two strategies for torrefaction were tested: one with a pre-dry step and one without. After torrefaction, big bluestem and CRP biomass showed an increase in energy density, making the biomass more attractive as a biofuel source than raw biomass. Big bluestem also showed slightly higher calorific values than that of CRP biomass. The torrefaction process had a significant effect on chemical composition and elemental composition of the biomass. Carbon content increased and oxygen content decreased as torrefaction temperature increased. Glucan and xylose decreased and lignin increased as torrefaction temperature increased. Pre-drying biomass before torrefaction is beneficial to torrefaction of biomass with high moisture content because moisture removal leads to less dry matter loss while maintaining the same calorific value.

Master of Science / Department of Family Studies and Human Services / Bronwyn Fees / Since the September 11th, 2001, terrorist attacks on the United States, a large number of service members have deployed multiple times to active combat zones as a result of U.S. involvement in the global war on terrorism. Army National Guard and Army Reserve families may find these deployments challenging as they are often isolated by living in civilian communities and have limited access to military support services and networks. Adolescents who live in these families may be particularly vulnerable as the stressors of parental deployment are layered on top of the normative stressors of adolescent development. This report will examine the challenges that adolescents and their families experience as a result of parental deployment. Additionally, protective factors that can help mitigate those challenges will also be discussed. Finally, Bronfenbrenner’s bioecological theory will be used as a framework to identify ways in which parents, schools, communities, and the U.S. Army can support adolescents, thus helping them to positively cope with parental deployment.

The subject of the diploma thesis is financial analysis of commercial insurance company. The diploma thesis is separated into two parts - theoretical and practical. The theoretical part describes financial analysis in general - users of information, sources of information, methods of financial analysis and then the attention is aimed to the specificity of insurance companies - accounting statements, methods and special ratios of financial analysis. The practical part is focused on the financial analysis of concrete insurance company.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Masters in Science. Johannesburg, September 2017. / Sable antelope numbers have been declining in protected areas of South Africa and they are listed as Vulnerable in the National Red List Assessment. In Kruger National Park, since 1986, the abundance of sable antelope has declined from 2240 to just under 400 individuals in 2014, making them at risk of local extirpation. The aim of the study was to explore some of the possible explanations, not explored before, for sable antelope (Hippotragus niger) perceived decline in the Kgaswane Mountain Reserve (KMR), in the North-West Province of South Africa. I therefore looked at assessing sable antelope use of space in relation to ‘high risk’ areas as determined by distances to fences, campsites and roads; determining the seasonal variations in the nutritional status of sable antelope; estimating calves recruitment, survival and population sex ratio. To achieve these objectives two sable antelope heifers were collared in the reserve, one from the ‘vlei’ herd and one from the ‘woodland’ herd. Both herds avoided ‘high risk’ areas, especially areas close to camping huts. The herds made little use of areas where there was lots of human movement. I expected the herds to utilise areas close to fences, especially after security burns along the perimeter of the park, but that was not the case as these areas were little utilised. Both herds preferred the tall grassland type of vegetation. As expected both herds utilised burnt areas and the woodland herd used these areas more than the vlei herd. Faecal crude protein and faecal phosphorus values during the dry season were higher compared to a previous study in KMR, which seems to suggest that currently the sable population in KMR is doing better compared to 2002-2003. Since 2011 until 2014, there were a total of 34 calves born with 15 missing after the study but only one mortality recorded. Therefore the reasons for the missing calves are still unclear. The best way to monitor survival of populations for long term studies would be to mark individuals in a population but unfortunately this was impossible for this study. I expected more females to be born as compared to males and this was not the case as there were more males (20) born than females (14), further indicating that potentially currently the population is doing better than in the past. / MT2018

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science, Johannesburg, South Africa 2017 / Concerns exist over the continual decline of marula trees (Sclerocarya birrea subsp. caffra) as a result of African elephant (Loxodonta africana) impact and a lack of recruitment and regeneration. One strategy of protecting adult marula trees is the usage of elephant mitigation methods. This study took place in Jejane Private Nature Reserve (JPNR), a protected area which recently opened up to the Greater Kruger National Park and had not had elephants in over 100 years. The aim of the study was to investigate the changes to the marula population structure in JPNR three years after the migration of elephants to the area due to fence removal, and to test whether African honeybees (Apis mellifera subsp. scutellata) could be used as a mitigation method for elephant impact on marula trees. A previous size-class survey had been done on a sample of JPNR’s marula population in 2009, prior to the fence removal in 2013. A resurvey of these trees was used to assess the elephant-induced impact and mortality levels on the marula trees and to compare these levels to previously recorded impact and mortality levels on marula trees in the Kruger National Park (KNP). Marula seed predation levels and seedling recruitment were also assessed to address recruitment concerns. The resurveyed marula population had declined by 23.8% post-elephant migration, with the highest annual mortality rates (AMR) and impact scores recorded for trees in the 5 - 11 m height classes. Impact scores on marula trees in JPNR were higher than impact scores recorded on KNP marula trees. Only two marula seedlings were found across all transects, with evidence of high seed predation on marula endocarps. JPNR displayed an adult-dominated marula population with a lack of regeneration, possibly due to a lack of fire which has increased available shelter for seed predators such as small mammals. African honeybees were then used to investigate their effectiveness as an elephant mitigation method and to compare this method against wire-netting (a method experimentally used to prevent ring-barking by elephants). Fifty active beehives were hung from 50 marula trees, with another 50 dummy (inactive) beehives hung from branches on the opposite ends of each beehive tree’s main stem. Fifty additional marula trees were wire-netted and a further 50 were used as control trees. Elephant impact on all 150 trees was measured prior to the addition of treatments and post-treatment addition for nine months. 54% of the control trees received some form of elephant impact, in comparison to 28% of the wire-netted trees and only 2% of the beehive trees. Wire-netting protected marula trees against bark-stripping, but did not prevent elephants from breaking branches. Beehives proved highly efficient at mitigating all forms of elephant impact. The financial cost and maintenance required for the beehive mitigation method is greater than that of wire- netting, but the beehives can provide honey and pollination services as an additional benefit. The results of this study illustrate that African honeybees can be used as an effective non-lethal mitigation method for elephant impact on marula trees and are a viable strategy to reduce human-elephant conflict in South Africa’s protected areas. / MT 2017

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, 2016. / Resource selection by animals is a hierarchical process, reflecting the spatio-temporal heterogeneity in biotic and abiotic environmental conditions and resources. In savannah ecosystems, the availability and nutritional quality of forage resources across the seasonal cycle constitute two of the main drivers of feeding choices, seasonal movements, and, ultimately, population dynamics of large herbivores. As a consequence of the increasing insularisation of protected areas in southern Africa, the understanding of the ecological requirements of confined populations of nomadic ungulates constitutes a crucial issue for their management. The study aimed at determining the effects of forage quality and availability across the seasonal cycle on the home range occupation and resource selection by eland in an insular-like protected area, the Kgaswane Mountain Reserve (KMR) in South Africa. I focused on three spatio-temporal scales of selection: seasonal home range selection over the available landscape; habitat selection within the seasonal home range; and selection for plant species included in the diet. The main objectives at the scales of landscape and habitat selection were: 1) to determine the extent and location of the seasonal home ranges utilised by collared adult female eland in the KMR, in order to identify the seasonally favoured resource units within the available landscape; and 2) to determine the influence of environmental drivers, including the seasonal variation in forage quality and abundance, on resource selection by eland at the two different scales. Four adult female eland were fitted with GPS collars, over the course of two years. The extent and location of annual and seasonal home ranges were estimated using a-LoCoH. The influence of environmental factors, including vegetation-type, burnt areas, and NDVI, on landscape- and habitat-scale selection of used locations at peak feeding times over available scattered points was tested using mixed-effects logistic regression models. Despite the small size of the KMR, eland occupied spatially distinct dry and wet season ranges. The dry season ranges were smaller than their wet season counterparts, and During the dry season, seasonal ranges were small, and were located in moderate to very green (as indicated by NDVI values) woodland areas in respect to the available landscape. Eland selected for dry grassland, wet grassland, and open shrubland (associated with low NDVI levels) during the wet season, when they coalesced into a nursery herd and occupied a relatively large home range. The selective use of burnt areas over the available landscape units was mostly restricted to the wet season, after a green herbaceous flush had been prompted by rainfall events. Within the seasonal home ranges, eland preferentially foraged on burnt woodland and open shrubland, where re-growth of woody plants was also available. The study animals also selected for locations characterized by low vegetation greenness and biomass as a consequence of the concentration of foraging activities in open areas where low-lying browse was accessible. At the smallest scale considered for this study, the two main objectives were: 1) to determine the changes in the use of vegetation types and burnt areas during foraging activities between two different seasons; 2) to determine forage selection at the plant species scale, as influenced by the phenophase of grasses and browse. In March-April 2015 (wet-early dry transition season) and July-August 2015 (mid-dry season), feeding sites of eland were located through both VHF-tracking and scanning from vantage points. Characteristics of used feeding sites were only descriptively addressed, and included vegetation type, burning, canopy cover, and soil catenal position. The greenness and basal cover of plant species were also recorded. Availability, acceptance, and dietary contribution for each species were calculated for the two seasons, while the influence of phenological traits on plant species selection was investigated through mixed-effects logistic regression models. Woody plants were consumed in larger proportions than grasses and herbaceous forbs during the entire study period. Woody forbs and shrublets such as Lippia javanica and Athrixia elata were particularly favoured. Eland targeted species offering high proportions of green leaves. During the wet-early dry transition, the deciduous Vangueria parvifolia was particularly selected for, while the consumption of evergreen species, including Searsia lancea, increased during the dry season. Most of the observed grazing took place on flushing burns during the wet-early dry transition. The decline in grass consumption was paralleled by a considerably lowered use of the burns and of the dry grassland during the dry season, as also reflected by collars data. The results indicated that eland in the KMR adjusted their landscape and habitat selection in response to spatio-temporal variations in the availability and quality of food resources. During the wet season, flushing burns provided accessible green forage to nursery herds. Conversely, evergreen woody plants probably represented a crucial resource for eland during the limiting dry season, when herbaceous plants were mostly dormant and foliage on deciduous species was unavailable. Therefore, environmental heterogeneity at different spatial scales likely constitutes a key factor for the persistence of eland populations in small, fenced reserves. / LG2017

[pt] Nos últimos anos no Brasil algumas modificações paramétricas foram implementadas na Previdência Social para tentar diminuir o crescente déficit entre os pagamentos de benefícios e o recebimento de contribuições. Nesse trabalho, Previdência Social é estudada sob um ponto de vista diferente: ao invés de uma análise focada apenas nos déficits atuais, utiliza-se a reserva de benefícios concedidos como uma forma de medir o impacto futuro das atuais regras de concessão de aposentadorias e pensões. Dependendo dos parâmetros utilizados, o valor da reserva supera o PIB real de 2005. O resultado também mostra que decisões sobre o aumento real do salário mínimo têm impacto bastante significativo nos gastos com benefício da Previdência Social. / [en] In the last few years the Brazilian Government had implemented some parametrical changes to the Social Security System so to try to diminish the growing deficit in between its benefits and contribution. In this work, the Social Security is studied under a different point of view: instead of looking at nowadays deficits, the necessary reserve to benefits already under payment will be calculated, so as to measure the future impact on the political decisions which are made today. Depending on the assumed parameters, the value of this reserve can be bigger than the GDP in 2005. This result shows also how the real value increase of the minimum wage impacts significantly this reserve.

Introdução: O processo de envelhecimento reprodutivo ocorre em virtude do declínio progressivo na quantidade e qualidade de óvulos que se inicia após a puberdade, se mantém ao longo da menacme, com redução gradual da fertilidade, e termina na menopausa, caracterizada pelo esgotamento do número de folículos e, consequentemente, da reserva ovariana funcional (ROF). A vida pré-natal constitui um importante período para o desenvolvimento dos órgãos genitais internos femininos e mudanças nessa fase podem ter repercussões futuras: quando o feto é submetido a condições adversas intrauterinas, mecanismos metabólicos e endócrinos de adaptação podem mudar o eixo metabólico pós-natal predispondo a certas doenças na vida adulta. Com base nesses dados, postulou-se que condições desfavoráveis de vida intrauterina que poderiam se refletir com alterações do peso ao nascer (PN) poderiam levar à reprogramação de genes envolvidos no controle da ROF e que talvez nascer pequeno para idade gestacional (PIG) ou grande (GIG) possibilitaria a interferência com a ROF estimada por meio das concentrações séricas do hormônio antimülleriano (AMH). Objetivos: O objetivo deste estudo foi avaliar a relação do PN com a ROF, estimada por meio da concentração sérica do AMH em mulheres na menacme com 34 a 35 anos de idade. Pacientes e Métodos: Trata-se de um estudo transversal aninhado a uma coorte de mulheres que nasceram no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP-USP), no período de 01 de junho de 1978 e 31 de maio de 1979. O desfecho primário avaliado foi a concentração sérica de AMH, um marcador da ROF, e sua correlação com o PN, divididos em três grupos: PIG, adequado para a idade gestacional (AIG) e GIG. Resultados: Das 274 pacientes incluídas no estudo, 19 foram classificadas como PIG, 238 como AIG e 17 como GIG. As concentrações médias de AMH não foram significativamente diferentes (p=0,11) entre mulheres na menacme nascidas PIG, AIG e GIG (2,14 ng/mL, 2,13 ng/mLe 2,57 ng/mL, respectivamente). Conclusão: Não se observou diferença nas concentrações séricas de AMH entre mulheres nascidas PIG, AIG e GIG avaliadas entre 34 e 35 anos de idade. A casuística avaliada permitiu detectar ou descartar uma grande diferença entre os grupos (effectsize de 0,7). Dessa forma, evidenciou-se que o PN não apresenta grande influência sobre a ROF, estimada pelas concentrações séricas do AMH, em mulheres na menacme, entre 34 e 35 anos de idade. Caso novos estudos evidenciem que diferenças pequenas ou moderadas nas concentrações séricas do AMH possam apresentar relevantes repercussões clínicas em mulheres nesta faixa etária, outras pesquisas serão necessárias, sendo os dados do presente estudo úteis para o cálculo amostral. / Background: The reproductive aging process occurs by a progressive decline in the quantity and quality of oocyte, starting after pubertal onset, remaining through menacme with gradual reduction of fertility and ends with menopause, which is the depletion of ovarian follicles and hence the depletion of functional ovarian reserve (FOR). Prenatal life corresponds to a critical window for the development of female internal genitalia and changes at this stage may have future repercussions: when the fetus is submitted to intra uterine adverse conditions, adaptive metabolic and endocrine mechanisms will change the metabolic axis in the postnatal period thereafter predisposing to several diseases in adulthood. Based on this correlation, we postulate that unfavorable conditions of intrauterine life that could reflect on birth weight (BW) could lead to the reprogramming of genes involved in the control of FOR and that maybe being born small for gestational age (SGA) or large for gestational age (LGA) could interfere with the FOR estimated through serum concentrations of Anti-Müllerian hormone (AMH). Objective: To investigate the relationship between BW and ROF estimated through AMH serum concentration in menacme women with 34-35 years old. Patients and Methods: This is a prospective birth cohort assessing all women who were born in Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP-USP) between June 1, 1978 and May 31, 1979. The primary endpoint was to evaluate serum AMH concentration, a marker of FOR and its correlation with BW divided into three groups: SGA, adequate for gestational age (AGA) and LGA. Results: Out of the 274 patients included in the study: 19 were classified as SGA, 238 as AGA, and 17 as LGA. The average of AMH concentrationwas not significantly different (p=0.11) among women in reproductive age born SGA, AGA and LGA (2.14 ng/mL, 2.13 ng/mL, and 2.57 ng/mL respectively. A variance analysis between the three groups and OR did not find a significant different between them (p=0.11). Conclusion: There was no difference in serum AMH concentration in women born SGA, AGA and LGA with 34 to 35 years old. This sample also allowed to detect or rule out a major difference between the groups (effect size of 0.7). In conclusion, BW does not have a great influence on FOR, estimated through serum AMH concentration in menacmewomen, between 34 and 35 years old. If new studies show clearly that small or moderate differences in serum AMH concentration could impact clinical outcomes in women at this age, further studies will be needed, and the data of this study could be useful for sample size calculation.

A Floresta Amazônica é palco de um grande número de atividades de desflorestamento, como a mineração artesanal, agropecuária e comércio de madeira. A fim de se ter uma diminuição dos impactos ambientais, os órgãos fiscalizadores têm tentado regular estas atividades e orientá-las para métodos de operação mais responsável. Este trabalho descreve a iniciativa por meio do monitoramento dessas áreas de floresta localizadas perto dessas regiões de desmatamento, porque os elementos fundamentais, tais como a biomassa e acúmulo de carbono das árvores podem ser adequadamente monitorados contra distúrbios ocasionais trazidos por essas atividades. A atual abordagem padrão na Amazônia é monitorar todas as árvores da floresta dentro de uma área chamada de transecto, também designado como inventário florestal, mantendo um registro rigoroso de seu comportamento e crescimento. No entanto, essas atividades são restritas às áreas de controle que estão localizados em regiões estratégicas e não representam toda a área a ser monitorada. Esta pesquisa explora uma nova metodologia baseada na geoestatística e destinada a otimização da amostragem, estendendo-se para o estudo de áreas florestais muito maiores, mantendo a utilização dos recursos humanos unitária inalterada, e, ao mesmo tempo, aumentar a superfície das áreas de estudo e a manter a confiança nos resultados. A metodologia proposta permite a seleção da Reserva Legal - RL, a ser feita de acordo com a distribuição real de acumulação de carbono da floresta, em vez de confiar na utilização de área percentual proposta por lei e no senso comum de proprietários / órgãos fiscalizadores. Esta metodologia foi aplicada na Floresta Nacional de Tapajós (FLONA Tapajós), no Estado do Pará, Brasil, utilizou-se de conjunto de dados disponíveis, para otimizar as amostras e monitorar a capacidade da floresta de armazenar carbono. A presente metodologia pretende contribuir para uma diminuição do custo das atividades de monitoramento por unidade de área, aumento da precisão para localização RL, e simplificação dos procedimentos através da aplicação de um conjunto de ferramentas de fácil utilização. Os resultados mostraram que a aplicação de estudos geoestatísticos para determinação de RL é um procedimento viável, pois a estrutura do variograma se mantém mesmo com a amostragem sofrendo uma diminuição randômica de até 50% da área de cobertura vegetal, conseguindo manter o mesmo resultado da amostragem na totalidade da cobertura vegetal. / The Amazon Rainforest is the scene of a large number of deforestation activities such as artisanal mining, agriculture and timber trade. For the purpose of have reduced environmental impacts, regulatory agencies have attempted to regulate these activities and direct them towards more responsible methods of operation. This paper describes the initiative by monitoring these forest areas located near these regions of deforestation, because the core elements, such as biomass and carbon accumulation of the trees can be adequately monitored against occasional disturbances brought by these activities. The current standard approach in the Amazon is to monitor all the trees of the forest within an area called the transect, also designated as forest inventory, keeping a strict record of their behavior and growth. However, these activities are restricted to control areas that are located in strategic regions and do not represent the whole area to be monitored. This research explores a new methodology based on geostatistics and designed to optimize the sampling, extending the study of much larger forest areas, keeping unchanged the use of human resources unit, and at the same time increase the surface areas of study and to maintain confidence in the results. The proposed methodology allows the selection of the Legal Reserve - RL, to be made according to the actual distribution of carbon accumulation in the forest, instead relying in using area percentage proposed by law and common sense of proprietary / regulatory agencies. This methodology was applied in the Tapajós National Forest (FLONA Tapajós), State of Pará, Brazil, we used the data set available, to optimize the sample and monitor the forest\'s ability to store carbon. This methodology intends to contribute to reducing the cost of monitoring activities per unit area, increased precision for location RL, and simplifying procedures by applying a set of easy to use tools. The results showed that application of geostatistical studies for determination of RL is a viable procedure, because the structure of the variogram is maintained even with a random sampling suffering decreased to 50% of the area of vegetation, even managing to keep the sampling result the total vegetation cover.