Carbon dynamics in aboveground coarse wood biomass of wetland forests in the northern Pantanal, Brazil

International audienceThis is the first estimation on carbon dynamics in the aboveground coarse wood biomass (AGWB) of wetland forests in the Pantanal, located in Central Southern America. In four 1-ha plots in stands characterized by the pioneer species Vochysia divergens Pohl (Vochysiaceae) forest inventories (trees ?10 cm diameter at breast height, DBH) have been performed and converted to predictions of AGWB by five different allometric models using two or three predicting parameters (DBH, tree height, wood density). Best prediction has been achieved using allometric equations with three independent variables. Carbon stocks (50% of AGWB) vary from 7.4 to 100.9 Mg C ha?1 between the four stands. Carbon sequestration differs 0.50?4.24 Mg C ha?1 yr?1 estimated by two growth models derived from tree-ring analysis describing the relationships between age and DBH for V. divergens and other tree species. We find a close correlation between estimated tree age and C-stock, C-sequestration and C-turnover (mean residence of C in AGWB)

Faciologia e análise tectônica de materiais de origem dos solos de Tabuleiros Costeiros no litoral Norte da Bahia.

O presente trabalho estudou os elementos faciológicos, arquiteturais, morfogenéticos e os reflexos da neotectônica no Grupo Barreiras, através de várias secções geológicas, análises de fotografias aéreas, imagens de satélite e de radar. O estudo mostra que os principais litofácies que compõem o Barreiras na região são os conglomerados maciços sustentados por lama (Cmf), conglomerados maciços sustentados por clastos (Cmc), arenitos lamosos conglomeráticos maciços (Alcm), arenitos lamosos conglomeráticos com estratificação cruzada (Alce), arenitos lamosos maciços (Alm) e argilitos maciços (Agm). A presença dos elementos arquiteturais fluviais canais (CH), finos de transbordamento (FF), fluxos gravitacionais de sedimentos (SG) e formas de leito arenosas (SB) indicam que os sedimentos do Grupo Barreiras são oriundos de sistemas fluviais entrelaçados e os depósitos ocorreram sob condições climáticas mais secas, em duas fases distintas, intercaladas por um clima úmido. Depois da deposição o Grupo Barreiras foi afetado por reflexos da tectônica, os quais podem ser inferidos pela direção preferencial das drenagens, anomalias das drenagens, padrão de drenagem dendrítico/paralelo, retangular e treliça, vales em forma de "U" com talvegues chatos, presença de basculamentos de blocos e vales dissimétricos. O trabalho desenvolvido dá subsídios para um melhor entendimento da gênese e evolução dos solos e do relevo na região, isto porque os litofácies e a neotectônica afetam a drenagem superficial e interna, condicionando processos intempéricos, pedológicos e morfodinâmicos

Dendê uma opção de cultivo para áreas degradadas na Amazônia.

O cultivo de dende surge como opcao para exploracao na Amazonia, tendo em vista sua adaptacao as condicoes edafoclimaticas da regiao. Esta cultura, com vida util de 25 anos, inicia sua producao aos quatro anos, tem produtividade media de 4t/oleo/ha/ano - 6t/oleo/ha/ano, colheita durante o ano todo, ausencia de entressafra, demanda expressivo contigente de mao-de-obra, fixando, dessa maneira, o homem na zona rural. Buscando apoiar e incentivar a expansao da cultura, a EMBRAPA-CPAA e o IRHO implantaram, no Amazonas, varios ensaios, objetivando desenvolver um programa de melhoramento, para a obtencao de material mais produtivo e melhor adaptado as condicoes da regiao. A producao media experimental de cachos aos quatro anos de idade variou de 12t/ha. Atualmente, EMBRAPA/CIRAD produzem sementes comerciais para atender os dendeicultores da regiao

Age-related and stand-wise estimates of carbon stocks and sequestration in the aboveground coarse wood biomass of wetland forests in the northern Pantanal, Brazil

In this study we use allometric models combined with tree ring analysis to estimate carbon stocks and sequestration in the aboveground coarse wood biomass (AGWB) of wetland forests in the Pantanal, located in central South America. In four 1-ha plots in stands characterized by the pioneer tree species Vochysia divergens Pohl (Vochysiaceae) forest inventories (trees ≤10 cm diameter at breast height, D) have been performed and converted to estimates of AGWB by two allometric models using three independent parameters (D, tree height H and wood density). We perform a propagation of measurement errors to estimate uncertainties in the estimates of AGWB. Carbon stocks of AGWB vary from 7.8±1.5 to 97.2±14.4MgC ha-1 between the four stands. From models relating tree ages determined by dendrochronological techniques to C-stocks in AGWB we derived estimates for C-sequestration which differs from 0.50±0.03 to 3.34±0.31MgC ha-1 yr-1. Maps based on geostatistic techniques indicate the heterogeneous spatial distribution of tree ages and C-stocks of the four studied stands. This distribution is the result of forest dynamics due to the colonizing and retreating of V. divergens and other species associated with pluriannual wet and dry episodes in the Pantanal, respectively. Such information is essential for the management of the cultural landscape of the Pantanal wetlands. © Author(s) 2011

Isolation of endophytic fungi in environments with and without traces of mercury contamination, Pantanal of Mato Grosso.

The mining activity in Mato Grosso is an economic source for many cities, especially in Poconé, where this activity is responsible for significant change in the landscape and the contamination of the ecosystem by mercury. This results in serious damage to biota enhanced by bioaccumulation capacity. Mercury is toxic to all organisms, however, some microorganisms have innate or acquired tolerance to metal. Therefore, our hypothesis is based on the premise that plants in contaminated environments with mercury harbor a specific community of endophytic fungi, therefore, variations in the colonization frequency of the endophytes in these plants are expected, when compared to places without contamination

Capacity resistance of endophytic fungi the mercury.

Contamination of biological systems by mercury represents a global concern, given the difficulty of degradation, persistence and potential toxicity of this metal in the environment. Remediation strategies of soils contaminated with mercury are required and the use of microorganisms as bioremediation agents is fully justified, in particular, the various mechanisms of tolerance to heavy metals allocated to them, particularly for fungi arising from various chemical processes, such as transformation valence, intra and extracellular precipitation and oxidation. Our hypothesis is that endophytic fungi isolated from areas contaminated by mercury present higher resistance to this metal