Les forêts tropicales contiennent dans leur biomasse aérienne un stock de carbone important à l’échelle de la planète. Mesurer ce stock et comprendre son fonctionnement permet de mieux saisir les enjeux liés à sa protection, sa destruction ou sa modification, ainsi que son rôle dans le cycle du carbone et les mécanismes climatiques globaux. Dans le cadre des problématiques économiques et écologiques liés au climat, les forêts sont progressivement prises en compte dans les programmes internationaux de mesures visant à réduire l’impact anthropique sur le climat (Protocole de Kyoto, 1998 ; Accord de Copenhague, 2009). L’intégration des forêts dans les mécanismes financiers liés au marché du carbone est clairement envisagée dans les années à venir (marché de carbone « d’origine forestière »).L’estimation de la biomasse aérienne d’une parcelle de forêt inventoriée nécessite l’utilisation successive de plusieurs modèles. Dans ces parcelles, le diamètre et l’espèce de chaque arbre sont renseignés. Ensuite, ces parcelles sont utilisées comme références pour l’extrapolation spatiale des valeurs de biomasse. Cette extrapolation repose souvent sur le traitement de signaux aériens (avions, satellites). Il est aussi possible d’utiliser covariables environnementales (climat, géologie, …).L’incertitude associée à l’estimation de la biomasse d’une région est le résultat de toutes les incertitudes associées à ces différents processus. Les connaissances actuelles ne nous permettent pas de quantifier cette incertitude. L’objectif de la thèse est de développer une méthodologie d’estimation de la biomasse qui permette la propagation des incertitudes ainsi que l’identification des sources de cette incertitude.Modèle de hauteur : Nous proposons un nouveau modèle de hauteur pour les forêts tropicales. Les paramètres de ce modèle ont un sens écologique et peuvent être prédits par des variables décrivant le peuplement sur lequel il est appliqué. Nous avons utilisé les données des projets Amalin et Bridge et sélectionné 42 parcelles réparties en Guyane dans lesquelles le diamètre et la hauteur de chaque arbre ont été mesurés.Modèle de densité de bois : Un modèle à été conçu pour associer à chaque espèce une distribution de densité de bois et non une valeur fixe. Nous avons utilisé les données du projet Bridge dans lequel la densité de bois a été mesurée sur 2504 arbres représentant 466 espèces.Modèle de biomasse: Nous avons montré par une analyse de sensibilité que les incertitudes des prédictions de hauteur et de densité de bois n’avaient qu’une part négligeable dans l’incertitude des prédictions de biomasse. L’amélioration de la précision de ces modèles n’est donc pas une priorité. En revanche, le modèle de hauteur peut être une source de biais.Modélisation spatiale : Les modèles développés ont été appliqués à différents réseaux de parcelles couvrant bien la zone littorale guyanaise : inventaires papetiers de l’ONF, réseau Guyafor, projet Amalin… Les prédictions de biomasse de ces parcelles sont utilisées dans un modèle spatiale. Nous produisons ainsi une carte de biomasse guyanaise associée à une carte de l’incertitude de cette estimation. / Tropical forest yield and important part of the aerial vegetation carbon stock on earth. Measuring and understanding this stock distribution is crucial for the management of the tropical forests facing the actual environmental challenges (REDD+, carbon market).Aerial Biomass estimation of forest census plots requires few models depending on the precision of the inventory: diameter models, height models, wood density models. Spatial extrapolation between census plots relies on aerial data (satellite measurements, images) or ground-based data (geology, altitude).The uncertainty of the estimation of a region’s biomass is the result of the uncertainty brought by all these models. The aim of the thesis is to develop models and methods to estimate the biomass of a region while propagating the uncertainties. This is applied to the neo-tropical forest of French Guiana (South America, Guianas Plateau).

In the 1980s, the meadows around Senotín in southern Bohemia were drained by subsurface pipe drainage. After considerable drought in 1992, this area was subjected to extensive research. In 1995, a part of the drained area was revitalized. The drainage pipeline was interrupted by seven clay screens, over four of them country lanes and shallow depressions were built. The research of this site was realized after revitalization and focused on the water regime of the soil and on the physical, chemical and biological properties of the soil. This thesis describes the state of water regime, physical and chemical parameters of soil in undrained, drained and revitalized areas 20 years after revitalization and compares them with data from research performed in the past. The rainfall and runoff data was measured in the catchment area, and soil samples were collected in the regular network. Research has shown that between 1998 and 2014 there has been a reduction in river runoff. However, a more detailed data analysis has identified the vegetation transpiration as the main factor. There has been no increase in soil retention or soil moisture. None of the investigated soil parameters on the revitalized area (bulk density, carbon and nitrogen content, C:N ratio, pH, and conductivity of the aqueous extract) is...

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Les sols sont la principale composantede l’écosystème terrestre et le plus grand réservoir de carbone organique sur Terre, étant très réactifs aux perturbations humaines et aux changements climatiques. Malgré leur importance dans les réservoirs de carbone, la dynamique du carbone des sols est une source importante d'incertitudes pour les prévisions climatiques futures. Le but de la thèse était d'explorer différents aspects d’études du carbone des sols (mesures expérimentales, modélisation et évaluation de bases de données) à différentes échelles spatiales (de l'échelle d'un profil à l'échelle globale). Nous avons souligné que l'estimation des stocks globaux de carbone du sol est encore assez incertaine.Par conséquent le rôle du carbone des sols dans la dynamique du climat devient l'une des principales incertitudes dans les modèles du système terrestre utilisés pour prédire les changements climatiques futurs. La deuxième partie de la thèse porte sur la présentation d'une nouvelle version du modèle IPSL-Land Surface appelé ORCHIDEE-SOM, intégrant la dynamique du 14C dans le sol. Plusieurs tests effectués supposent que les améliorations du modèle devraient se focaliser davantage sur une paramétrisation dépendante de la profondeur,principalement pour la diffusion, afin d'améliorer la représentation du cycle global du carbone dans les modèles de surface terrestre, contribuant ainsi à contraindre les prédictions futures du réchauffement climatique. / Soils are the major components ofthe terrestrial ecosystems and the largest organiccarbon reservoir on Earth, being very reactive tohuman disturbance and climate change. Despiteits importance within the carbon reservoirs, soilcarbon dynamics is an important source ofuncertainties for future climate predictions. Theaim of the thesis was to explore different aspectsof soil carbon studies (Experimentalmeasurements, modeling, and databaseevaluation) at different spatial scales (from thescale of a profile to the global scale). Wehighlighted that the estimation of the global soilcarbon stocks is still quite uncertain.Consequently, the role of soil carbon in theclimate dynamics becomes one of the majoruncertainties in the Earth system models (ESMs)used to predict future climate change. Thesecond part of thesis deals with the presentationof a new version of the IPSL-Land SurfaceModel called ORCHIDEE-SOM, incorporatingthe 14C dynamics in the soil. Several tests doneassume that model improvements should focusmore on a depth dependent parameterization,mainly for the diffusion, in order to improve therepresentation of the global carbon cycle inLand Surface Models, thus helping to constrainthe predictions of the future soil organic carbonresponse to global warming.

Comparing the future state of natural capital and ecosystem services with quantitative scenarios  is essential in the decision-making process for a sustainable management of forest landscapes. In Sweden, an intensified forest management will likely be necessary to meet future demands of woody biomass as a source of bioenergy and building materials. At the same time an intensified forest harvest can cause conflicts with goals  for biodiversity conservation and reduce the amount of carbon being stored the forest. This study conducted a scenario analysis to evaluate how different types of forest management would affect changes in carbon stock between the above ground biomass in a Swedish forest and the biomass harvested from the forest. Potential conflicts between the harvesting scenarios and the in Sweden critically endangered White-backed Woodpecker (Dendrocopos leucotos) was also evaluated. The White-backed Woodpecker can be seen as an umbrella species, which means that there are about 200 other endangered plant and animal species that depend on the same kind of forest environments and could therefore be a measure of the state of the forest biodiversity in Sweden.  The forest landscape model LANDIS-II was used to simulate vegetation dynamics in species composition, age structure and biomass while considering disturbances only from harvesting. The simulation had a 100-year timeframe and used initial conditions gathered from a previous case study done in Sweden. The IPCC’s representative concentration pathway 4.5 was used to simulate impact from climate change. A business as usual scenario was simulated along with an intensified harvesting scenario and a conservation scenario to evaluate the impact on carbon sequestration in the aboveground  biomass  and the impact on the White-backed Woodpecker  habitat  between different forest management scenarios. The change in the stored and harvested carbon was calculated using the Carbon Stock Change Method and by comparing the initial biomass values with the values from the last ten years of the simulation. A habitat suitability score was made with respect to two key habitat requirements for the White-backed Woodpecker (1) the fraction of deciduous trees in the forest; and (2) the age structure of the forest.   From the result it was found that the carbon stock change in the forest was relatively stable for all the simulated scenarios during the 100-year period. The forest carbon stock for the intensified harvesting scenario was 1.04 of the initial carbon stock of the simulation while business as usual was 1.08 and the conservation scenario 1.10.  A conservation scenario would therefore be preferable if the forest landscape is to be used mainly as a carbon sink. If biomass extraction is to be increased to meet future demands for bioenergy and woody products, it should be noted that the intensified harvesting led to a 23.6 increase of the initial biomass harvest values while business as usual had a 4.2 increase and the conservation scenario a 3.1 increase. The result also suggests that increasing the proportions of deciduous and old forest to recreate  the White-backed Woodpecker’s preferred habitat require considerable time and effort and cannot likely be achieved with the current business as usual scenario nor with the intensified harvesting or conservation scenarios simulated in this study. Thus, a more ambitious and targeted restoration effort is needed if the species is to be preserved.   How the forest should be sustainably managed in the future depends on which interests takes priority in decision-making. However, a forest landscape model can provide valuable information throughout the management process so that more informed decisions can be made while also saving  time, money and resources better used elsewhere. / Att jämföra det framtida tillståndet för naturkapital och ekosystemtjänster med kvantitativa scenarier är väsentligt i beslutsprocessen för en hållbar förvaltning av skogslandskap. I Sverige kommer sannolikt ett intensifierat skogsbruk att bli nödvändigt för att möta framtida krav på biomassa till bioenergi och byggmaterial. Samtidigt kan en intensifierad skogsavverkning orsaka konflikter med målet att bevara biologisk mångfald och öka mängden kol lagrad i skogen. Denna studie genomförde en scenarioanalys för att utvärdera hur olika typer av skogsskötsel påverkar i kolbalansen i en svensk skog och mängden biomassa som avverkas från skogen. Potentiella konflikter mellan skogsskötsel och den i Sverige kritiskt hotade vitryggiga hackspetten (Dendrocopos leucotos) utvärderades också. Den vitryggiga hackspetten kan ses som en paraplyart, vilket innebär att det finns cirka 200 andra hotade växt- och djurarter som är beroende av samma sorts skogsmiljöer, och den kan därför vara ett mått på tillståndet för den skogsknutna biologiska mångfalden i Sverige. Skogslandskapsmodellen LANDIS-II användes för att simulera vegetationsdynamik för artsammansättning, åldersstruktur och biomassa samtidigt som man beaktade störningar endast från avverkning. Simuleringen gjorde för en 100-årsperiod och använde initiala förutsättningar från en tidigare fallstudie gjord i Sverige. IPCC:s representativa koncentrationsväg 4.5 användes för att simulera påverkan från klimatförändringar. Ett "business as usual"-scenario simulerades tillsammans med ett intensifierat avverkningsscenario och ett bevarandescenario för att utvärdera påverkan på kolbindning i den stående biomassan och påverkan på habitat för vitryggig hackspett mellan olika skogsskötselscenarier. Förändringen i det lagrade kolet beräknades med hjälp av ”Carbon Stock Change”-metoden och genom att jämföra de initiala biomassavärdena med värdena från de senaste tio åren av simuleringen. Ett habitatlämplighetspoäng gjordes med avseende på två viktiga habitatkrav för vitryggig hackspett (1) andelen lövträd i skogen; och (2) skogens åldersstruktur. Av resultatet visade det sig att kolförrådets förändring i skogen var relativt stabil för alla de simulerade scenarierna under 100-årsperioden. Skogens kollager för det intensifierade avverkningsscenariot var 1,04 av simuleringens initiala värden medan ”business as usual” var 1,08 och bevarandescenariot 1,10. Ett bevarandescenario vore därför att föredra om skogslandskapet främst ska användas som kolsänka. Om biomassautvinningen ska ökas för att möta framtida krav på bioenergi och träprodukter bör det noteras att den intensifierade avverkningen ledde till en ökning med 23,6 av de initiala skördevärdena för biomassa medan ”business as usual” hade en ökning med 4,2 och bevarandescenariot med 3,1. Resultatet tyder också på att en ökning av andelen lövskog och gammal skog för att återskapa vitryggig hackspetts föredragna habitat kräver avsevärd tid och ansträngning och sannolikt inte kan uppnås med det nuvarande scenariot med ”business as usual” eller med de intensifierade avverknings- eller bevarandescenarierna som simuleras i detta studie. Det behövs alltså en mer ambitiös och målinriktad restaureringsinsats om arten ska bevaras. Hur skogen ska skötas hållbart i framtiden beror på vilka intressen som prioriteras i beslutsfattandet. En skogslandskapsmodell kan dock ge värdefull information under hela skötselprocessen så att mer informerade beslut kan fattas samtidigt som det sparar tid, pengar och resurser som kan användas bättre på annat håll.

Biomass and carbon stock of the natural forests in Vietnam are still not clear due to limitation of knowledge and financial. In this paper, the results of estimating biomass and carbon stocks of the natural forests at Me Linh Biodiversity Station are shown. There are two forest types in this study: the forest vegetation restored after shifting cultivation (vegetation type I) and the forest vegetation restored after clear cutting exploitation (vegetation type II). As the results, the estimated biomass of the forest vegetation restored after shifting cultivation is 86.80 ton.ha-1 and the estimated biomass of the forest vegetation restored after clear cutting exploitation is higher, about 131.59 ton.ha-1. The carbon stock in plants was about 43.40 ton.ha-1 of vegetation type I and 65.79 ton.ha-1 of vegetation type II. The carbon storage in soil of vegetation type I is 79.01 ton.ha-1 and vegetation type II is 99.65 ton.ha-1. Hence, the total of carbon stock in forest vegetation I and II are accounted by 122.41ton.ha-1 and 165.44 ton.ha-1, respectively. In general, it can be pointed out that the naturally recovering secondary forest at Me Linh Station is the secondary young forest with the low economic value due to shortly restored process (about 10-20 years), the flora is not rich and abundant, and there are only commonly pioneer and light demanding tree species. / Sinh khối và trữ lượng các bon của rừng tự nhiên ở Việt Nam vẫn ít được quan tâm của do hạn chế về kiến thức và tài chính. Trong bài báo này, chúng tôi đưa ra kết quả của việc ước lượng sinh khối và tổng hợp các bon của các thảm thực vật rừng thứ sinh phục hồi tự nhiên tại Trạm Đa dạng Sinh học Mê Linh, tỉnh Vĩnh Phúc- Việt Nam, nơi có loại hình thảm thực vật chính, đó là thảm thực vật phục hồi sau nương rẫy (kiểu thảm thục vật I) và thảm thực vật phục hồi sau khai thác kiệt (kiểu thảm thực vật II) nhằm mục đích đánh giá tiềm năng của rừng thứ sinh tại khu vực nghiên cứu. Sinh khối của thảm thực vật phục hồi sau nương rẫy là 86,80 tấn/ha. Sinh khối của thảm thực vật phục hồi sau khai thác cao hơn, đạt 131.59 tấn/ha. Lượng các bon hấp thu trong đất của thảm thực vật I là 79,01 tấn/ha và thảm thực vật II là 99,65 tấn/ha. Như vậy, tổng lượng các bon được hấp thu trong mỗi loại hình thảm thực vật trên là: 122,41 tấn/ha (thảm thực vật I) và 165,14 tấn/ha. Nhìn chung, rừng thứ sinh phục hồi tự nhiên tại Trạm Đa dạng Mê Linh chủ yếu là rừng non thứ sinh, ít có giá trị kinh tế do quá trình phục hồi diễn ra ngắn (khoảng 10-20 năm) nên thành phần thực vật nghèo nàn, không phong phú, thành phần chính chủ yếu là các cây gỗ tiên phong, ưa sáng.

O serviço ecossistêmico de regulação climática global (SERCG) ofertado pelas florestas é reconhecido pelo seu papel crucial na mitigação da mudança climática. Tais ecossistemas atuam como sumidouros de carbono atmosférico por meio do CO2 sequestrado e armazenado nos tecidos vivos dos vegetais. Porém, processos de continuo desmatamento afetam negativamente a capacidade desses ecossistemas em ofertar o SERCG, especialmente em florestas tropicais que possuem alto potencial de ofertar o serviço e sofrem forte pressão devido ao desenvolvimento agroindustrial. As paisagens atlânticas brasileiras são exemplos dessa condição, em especial no estado de São Paulo, onde a vegetação natural foi primordialmente convertida em pastagens e silvicultura. Avaliar e gerenciar os estoques e fluxos de serviços dos ecossistemas em paisagens espacialmente heterogêneas constitui um dos principais desafios da ciência da sustentabilidade da paisagem. Frente a esse contexto, o presente estudo tem o objetivo de avaliar os estudos sobre a valoração ecológica do SERCG da floresta tropical e analisar a oferta deste serviço em paisagens atlânticas pressionadas pela atividade pecuária. Inicialmente, investigamos as tendências e lacunas que envolvem a pesquisa dos atributos biofísicos do SERCG nas florestas tropicais e subtropicais na escala pan-tropical através de uma revisão sistemática da literatura sobre o tema nos últimos 20 anos, de acordo com uma abordagem exploratória qualitativa. Constatamos que as estimativas de estoque de carbono das florestas tropicais apresentam alta variabilidade, que os fatores de influência mais recorrentes sobre o SERCG na literatura são as mudanças no uso da terra e a riqueza de espécies e que o SERCG possui maior número de relações de sinergia que de trade-off com outros SEs. Em um segundo momento, analisamos a oferta do serviço de regulação em paisagens atlânticas do Vale do Paraíba do Sul (SP), considerando o processo de substituição de floresta nativa por campo antrópico. Levantamos dados em campo para o cálculo de biomassa acima do solo de fragmentos florestais em diferentes estágios sucessionais e em campo antrópico, e transformamos esses dados em estoques de carbono. Os dados subsidiaram os cálculos de SERCG para 16 paisagens que tinham diferentes proporções de áreas de floresta e campo. Também avaliamos a influência da configuração da paisagem sobre a produção de biomassa dos remanescentes florestais. Obtivemos valores de estoque de carbono de 16,9±7,25 MgC há-1 para a floresta inicial, 34,8±12,05 MgC ha-1 para floresta intermediária-avançada e 0,53±0,26 MgC ha-1 para campo antrópico. Identificamos que a distância ao fragmento mais próximo diminui a biomassa das florestas em estágio inicial, enquanto a área média dos fragmentos localizados em um raio de 500 m ao redor do fragmento amostrado aumenta a biomassa das florestas em estágio intermediário-avançado. Destacamos o fato de que as paisagens avaliadas com > 40% do território florestado possuem um diferencial na contribuição da oferta do SERCG, devido ao aumento em número e área de fragmentos de floresta em estágio intermediário-avançado. Apesar do contraste entre a contribuição dos pequenos fragmentos em estágio inicial e os de estágio mais avançado, a ocorrência dos primeiros implica em uma maior oferta do SERCG em escala de paisagem. Ademais, a conservação desses fragmentos não só influenciaria na oferta do serviço de regulação climática, mas também na oferta de outros com os quais apresenta relações sinérgicas / The global climate regulation ecosystem service (GCRES) provided by forests is recognized for its crucial role in mitigating climate change. These ecosystems act as sinks of atmospheric carbon by sequestering and stocking CO2 in the living tissues of plants. However, continuous deforestation processes decreases its capacity to supply GCRES, especially in tropical forests which have high potential to provide the service and suffer strong pressure due to agroindustrial development. Brazilian Atlantic landscapes are examples of this condition, especially in the state of São Paulo, where natural vegetation was primarily converted into cattle pastures and forestry. Assessing and managing ecosystem services stocks and flows in spatially heterogeneous landscapes is one of the major challenges of landscape sustainability science. In this context, our objective is to evaluate the studies on the ecological valuation of GCRES in tropical forest and to analyse the supply of this service in Atlantic landscapes pressured by livestock activity. Initially, we investigated the trends and gaps that involve the biophysical attributes of GCRES in tropical and subtropical forest at a pan-tropical scale through a systematic review of the literature on the subject in the last 20 years, according to a qualitative exploratory approach. We found that (1) estimates of carbon stock from forests show high variability; (2) the most recurrent factors that influence on GCRES are land use and species richness; and (3) GCRES has a greater number of synergy relations with other SEs compared to trade-off relations. Secondly, we analysed the supply of the regulation service in Atlantic landscapes of the Paraiba do Sul Valley (SP, BR), considering the process of replacing native forest by pasturelands. We collected field data to calculate pasture and forest fragments aboveground biomass at different successional stages, and transformed these data into carbon stocks. This data subsidized the calculations of GCRES supply for 16 landscapes that had different proportions of forest and pasture areas. We also evaluated the influence of landscape configuration on forest remnants biomass production. We found carbon stock values of 16.9 ± 7.25 MgC ha-1 in initial forest, 34.8 ± 12.05 MgC ha-1 in intermediate-advanced forest and 0.53 ± 0.26 MgC ha-1 in cattle pastures. We identified that the distance to the nearest fragment decreases the early-stage forest biomass, while the average area of fragments located within a radius of 500 m around the sampled fragment increases the intermediate-advanced stage forest biomass. We highlight the fact that the evaluated landscapes with more than 40% of forested area have a differentiated contribution to the SERCG supply due to the increase in number and area of intermediate-advanced stage forest fragments. In spite of the contrast between the contribution of small fragments in the early stages and those of more advanced stage, the presence of the former implies a greater supply of SERCG at the landscape scale. In addition, the conservation of these fragments would not only influence the supply of the climate regulation service, but also the supply of other services with which it has synergistic relations

Existe grande demanda pelo etanol de cana-de-açúcar. Para suprir essa demanda, uma forma é o aumento de produtividade pelo etanol de 2ª geração proveniente da palha. A remoção dessa palha pode alterar atributos químicos e físicos do solo. O objetivo deste trabalho foi caracterizar o solo e avaliar os impactos da manutenção de diferentes quantidades de palha de cana-de-açúcar nos atributos químicos e físicos do solo. O experimento foi conduzido próximo a Capivari - SP na unidade Bom Retiro (BR) e próximo a Valparaiso - SP na unidade Univalem (UV). O tipo de solo de cada área experimental foi, respectivamente, Latossolo Vermelho distrófico típico e Argissolo Vermelho-Amarelo distrófico típico. O delineamento utilizado foi blocos ao acaso com seis tratamentos e quatro repetições. Os tratamentos testados foram as seguintes quantidades de palha em Mg ha-1 de massa de matéria seca: BR (0; 3,4; 7,8; 13,0; 16,6; 15,6) e UV (0; 4,2; 8,7; 15,1; 18,9; 23,3). Foram avaliados atributos químicos e físicos tais como teor e estoques de carbono, fracionamento da matéria orgânica dos solos, pH e resistência do solo à penetração. As camadas avaliadas foram diferentes na caracterização (0-10; 10-20; 20-30; 30-40; 40-50; 50-60; 60-80 e 80-100 cm) e após 1 ano de efeito da palha (0-5 e 0-10 cm). Os resultados demonstraram que os solos não apresentavam variações significantes nos teores de macronutrientes e C no momento de implantação dos experimentos, indicando que dentro de cada área experimental o solo era homogêneo e, portanto, adequado para implantação do experimento. Transcorrido um ano de experimento, as diferentes quantidades de palha não alteraram os teores de C (independente da profundidade avaliada) e nem a distribuição das frações da MOS. Desta forma, conclui-se que os efeitos da retirada da palhada de cana-de-açúcar nos atributos químicos e físicos do solo, se existirem, serão expressos em um tempo maior de condução do experimento. Essa consideração pode ser colocada também para pH e resistência à penetração / Globally, there is increasing demand for sugarcane ethanol. To meet this demand, one way is to increase productivity by 2nd generation ethanol using sugarcane straw as feedstock. Straw removal management can change the chemical and physical soil properties. The aim of this study was to characterize the soil and assess the impacts of maintenance of different amounts of sugarcane straw on soil chemical and physical properties. Two experiments were conducted near Capivari - SP in Bom Retiro mill (BR) and close to Valparaiso - SP in Univalem mill (UV). The soil type of each experimental area was, respectively, a Rhodic Kandiudox (USDA Soil Taxonomy) and a Kanhaplic Haplustults (USDA Soil Taxonomy). The experimental design used was a randomized blocks with six treatments and four replications. The treatments were the following amounts of straw in Mg ha-1 of dry matter: BR (0, 3.4, 7.8, 13.0, 16.6, 15.6) and UV (0, 4 2, 8.7, 15.1, 18.9, 23.3). Soil chemical and physical attributes were assessed, such as content and carbon stocks, fractionation of soil organic matter, pH and soil resistance to penetration. Soil sampling was performed for the 0-10; 10-20; 20-30; 30-40; 40-50; 50-60; 60-80 and 80-100 cm layers in the soil characterization (base line) and after 1 year of effect of straw, soil was sampled at 0-5 and 0-10 cm depth. Our results showed that the soils had no significant variation in the macronutrient and C contents and C at the time of implantation of the experiments, indicating that the soil in each experimental area was homogeneous and therefore suitable for implementation of the experiment. After one year of experiment, different amounts of straw did not alter the contents of C (regardless of the assessed depth) nor the distribution of SOM fractions. Thus, we concluded that the effects of the sugarcane straw removal on soil chemical and physical attributes, if any, it should be expressed in a long-term experiment

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-10-05T17:00:06Z No. of bitstreams: 1 DISSERTACAO-RICARDOSOARES2007.pdf: 894553 bytes, checksum: 7aed12a6e12903185b48ce61f91107a2 (MD5) / Made available in DSpace on 2017-10-05T17:00:06Z (GMT). No. of bitstreams: 1 DISSERTACAO-RICARDOSOARES2007.pdf: 894553 bytes, checksum: 7aed12a6e12903185b48ce61f91107a2 (MD5) / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / Existe o consenso de que as Terras Pretas de Índio (TPI) Amazônicas são extremamente eficientes em reter grandes quantidades de Matéria Orgânica do Solo (MOS), e por longo tempo. Porém, os efeitos sobre as Substâncias Húmicas e as Frações Físicas do Solo nestes ambientes tropicais, assim como o estado de agregação influenciado pela MOS de origem pirogênica são pouco conhecidos. O objetivo deste trabalho foi avaliar as alterações na agregação de solos antropogênicos e na distribuição das frações orgânicas do solo de origem Antropogênica e não Antropogênica, do Estado do Amazonas, Brasil. Este estudo foi realizado em cinco argissolos sob florestas secundárias de diferentes idades, sendo dois solos caracterizados como TPI, e os restantes argissolos convencionais. Os resultados mostraram que o solo de uma das áreas de TPI (P02) apresentou os maiores valores de agregados estáveis em água, pouco diferindo estatisticamente da outra área amostrada de TPI (P01). O solo da área P02 foi o que apresentou os maiores: Diâmetro Médio Ponderado (DMP), Diâmetro Médio Geométrico (DMG), Índice de Estabilidade de Agregados (%IEA) e a porcentagem de agregados maior que 2.00 mm, indicando que o maior tempo de pousio, proporcionou um incremento no tamanho dos agregados e na qualidade estrutural do solo. Quanto ao Carbono Orgânico Total (COT), ao se comparar as cinco áreas (P01, P02, P03, P04 e P05), constatou-se a hegemonia das TPI’s em reter mais MOS, do que em solos não antropogênicos, o que é corroborado pelos estoques de carbono. O Fracionamento Químico da MOS mostrou-se eficaz na diferenciação do tipo de solo, verificando-se um maior teor do carbono da fração Humina no solo de TPI da área P02, pouco diferindo estatisticamente da área P01. As distribuições do peso das Frações Leves também diferiram significativamente entre os tipos de origem do solo. As áreas de TPI apresentaram os maiores valores da Fração Leve Livre e Intra-Agregado quando comparadas com as áreas não antropogênicas, demonstrando haver uma maior proteção física das Frações Leves neste sistema. O conteúdo de carbono e nitrogênio Total das frações leves foram maiores nas áreas de TPI, do que nas áreas não antropogênicas. A área P02 foi a que apresentou a melhor qualidade ambiental e menor estado de degradação, devido à qualidade e quantidade da MOS nela contida. / There is consensus that the black soils of Amazonian known as Terras Pretas de Índio (TPI) are extremely efficient in retaining great quantities of soil organic material (SOM), for long periods of time. However, various important characteristics of TPIs are little known: the distribution of organic matter between humic fractions, and between physical fractions, as well as any change in state of soil aggregation due to SOM of pyrogenic origin. The object of this work is to evaluate and compare the states of aggregation and the distributions of organic fractions in soils of anthropogenic (TPI) and non anthropogenic origin from the State of Amazonas, Brazil. This study was made using soil samples from five areas of the soil type classified as "argissolo" under Brazilian soil classification, two of them TPIs and three which exhibited no evidence of anthropogenic alteration. One of the TPIs (P02) had greater proportions of aggregates stable in water and the other TPI (P01) was little different, statistically, from this. The P02 soil aggregates had the greatest pondered mean diameter (PMD), geometric mean diameter (GMD), fraction with diameter > 2mm, and aggregate stability index (%ASI), indicating that a greater undisturbed time had led to this greater structuring. The TPIs had much higher total organic carbon contents (TOCs) than the other soils, a result which was corroborated by their determined carbon stocks. Chemical fractionation of organic matter also distinguished the TPIs from the other soils, the humin fraction being higher in the TPIs, especially P02. Physical fractionation also showed differences in the distribution of organic matter. The TPI soils had higher fractions of free light material and intra-aggregate light material, compared with the non anthopogenic soils, demonstrating that protection of organic matter was greater in the TPI soils. The carbon and nitrogen contents of the light fractions from the TPIs were greater than those of the comparison soils. The P02 soil exhibited the best environmental quality, principally because of its high SOM content.

Existe grande demanda pelo etanol de cana-de-açúcar. Para suprir essa demanda, uma forma é o aumento de produtividade pelo etanol de 2ª geração proveniente da palha. A remoção dessa palha pode alterar atributos químicos e físicos do solo. O objetivo deste trabalho foi caracterizar o solo e avaliar os impactos da manutenção de diferentes quantidades de palha de cana-de-açúcar nos atributos químicos e físicos do solo. O experimento foi conduzido próximo a Capivari - SP na unidade Bom Retiro (BR) e próximo a Valparaiso - SP na unidade Univalem (UV). O tipo de solo de cada área experimental foi, respectivamente, Latossolo Vermelho distrófico típico e Argissolo Vermelho-Amarelo distrófico típico. O delineamento utilizado foi blocos ao acaso com seis tratamentos e quatro repetições. Os tratamentos testados foram as seguintes quantidades de palha em Mg ha-1 de massa de matéria seca: BR (0; 3,4; 7,8; 13,0; 16,6; 15,6) e UV (0; 4,2; 8,7; 15,1; 18,9; 23,3). Foram avaliados atributos químicos e físicos tais como teor e estoques de carbono, fracionamento da matéria orgânica dos solos, pH e resistência do solo à penetração. As camadas avaliadas foram diferentes na caracterização (0-10; 10-20; 20-30; 30-40; 40-50; 50-60; 60-80 e 80-100 cm) e após 1 ano de efeito da palha (0-5 e 0-10 cm). Os resultados demonstraram que os solos não apresentavam variações significantes nos teores de macronutrientes e C no momento de implantação dos experimentos, indicando que dentro de cada área experimental o solo era homogêneo e, portanto, adequado para implantação do experimento. Transcorrido um ano de experimento, as diferentes quantidades de palha não alteraram os teores de C (independente da profundidade avaliada) e nem a distribuição das frações da MOS. Desta forma, conclui-se que os efeitos da retirada da palhada de cana-de-açúcar nos atributos químicos e físicos do solo, se existirem, serão expressos em um tempo maior de condução do experimento. Essa consideração pode ser colocada também para pH e resistência à penetração / Globally, there is increasing demand for sugarcane ethanol. To meet this demand, one way is to increase productivity by 2nd generation ethanol using sugarcane straw as feedstock. Straw removal management can change the chemical and physical soil properties. The aim of this study was to characterize the soil and assess the impacts of maintenance of different amounts of sugarcane straw on soil chemical and physical properties. Two experiments were conducted near Capivari - SP in Bom Retiro mill (BR) and close to Valparaiso - SP in Univalem mill (UV). The soil type of each experimental area was, respectively, a Rhodic Kandiudox (USDA Soil Taxonomy) and a Kanhaplic Haplustults (USDA Soil Taxonomy). The experimental design used was a randomized blocks with six treatments and four replications. The treatments were the following amounts of straw in Mg ha-1 of dry matter: BR (0, 3.4, 7.8, 13.0, 16.6, 15.6) and UV (0, 4 2, 8.7, 15.1, 18.9, 23.3). Soil chemical and physical attributes were assessed, such as content and carbon stocks, fractionation of soil organic matter, pH and soil resistance to penetration. Soil sampling was performed for the 0-10; 10-20; 20-30; 30-40; 40-50; 50-60; 60-80 and 80-100 cm layers in the soil characterization (base line) and after 1 year of effect of straw, soil was sampled at 0-5 and 0-10 cm depth. Our results showed that the soils had no significant variation in the macronutrient and C contents and C at the time of implantation of the experiments, indicating that the soil in each experimental area was homogeneous and therefore suitable for implementation of the experiment. After one year of experiment, different amounts of straw did not alter the contents of C (regardless of the assessed depth) nor the distribution of SOM fractions. Thus, we concluded that the effects of the sugarcane straw removal on soil chemical and physical attributes, if any, it should be expressed in a long-term experiment