9 documents found, page 1 of 1
Improving simulated Amazon forest biomass and productivity by including spatial...
Castanho, Andrea Dde Almeida; Coe, Michael T.; Costa, Marcos Heil; Malhi, Yadvinder Singh; Galbraith, David R.; Quesada, Carlos AlbertoDynamic vegetation models forced with spatially homogeneous biophysical parameters are capable of producing average productivity and biomass values for the Amazon basin forest biome that are close to the observed estimates, but these models are unable to reproduce observed spatial variability. Recent observational studies have shown substantial regional spatial variability of above-ground productivity and bioma...
Pathways for recent Cerrado soybean expansion : extending the soy moratorium an...
Nepstad, Lucy S.; Gerber, James S.; Hill, Jason D.; Dias, Lívia Cristina Pinto; Costa, Marcos Heil; West, Paul C.The Brazilian Soy Moratorium has effectively reduced forest conversion for soybeans in Amazonia. This has come at the expense of the region’s pasturelands, which have increasingly ceded space for compliant soy expansion. The question of extending the policy to the Cerrado, where recent soy expansion has come at the cost of ecologically valuable vegetation, plugs into a wider discussion on how to reconcile compe...
Variação espacial e temporal da precipitação no estado do Pará
Moraes, Bergson Cavalcanti de; Costa, José Maria Nogueira da; Costa, Antonio Carlos Lôla da; Costa, Marcos HeilEstudos sobre a climatologia das precipitações no Estado do Pará são essenciais para o planejamento das atividades agrícolas. A variação da precipitação anual e sazonal no Estado do Pará foi analisada com base em séries históricas de 23 anos (1976-1998) de dados diários de chuva. A análise foi realizada para 31 localidades do Estado do Pará, sendo os resultados representados em mapas com a utilização de técnica...
Mecanismos de controle da variação sazonal da transpiração de uma floresta trop...
Souza Filho, José Danilo da Costa; Ribeiro, Aristides; Costa, Marcos Heil; Cohen, Julia Clarinda PaivaNo presente trabalho foram estudadas a variação sazonal da transpiração, de uma floresta tropical, e sua dependência com fatores bióticos e abióticos. Utilizaram-se dados do projeto CARBOPARÁ, parte integrante do Experimento de Grande Escala da Biosfera-Atmosfera na Amazônia (LBA), coletados na reserva florestal de Caxiuanã, região nordeste da Amazônia. A evapotranspiração total num intervalo de 39 dias para o ...
Effects of large-scale changes in land cover on the discharge of the Tocantins ...
Costa, Marcos Heil; Botta, Aurélie; Cardille, Jeffrey A.Studies that relate changes in land cover with changes in river discharge at the small scale (<1 km2) are abundant. These studies generally indicate that deforestation causes an increase in the annual mean discharge. However, previous studies that evaluated the effects of changes in land cover in larger river basins (>100 km2) usually have not found similar relationships. Here we analyse a 50-year long time ser...
Overview of the large-scale biosphere–atmosphere experiment in Amazonia data mo...
Costa, Marcos Heil; Borak, Jordan S.; Gonçalves, Luis Gustavo Gonçalves de; Saleska, Scott R.; Baker, Ian; Restrepo-Coupe, Natalia; Muza, Michel NobreA fundamental question connecting terrestrial ecology and global climate change is the sensitivity of key terrestrial biomes to climatic variability and change. The Amazon region is such a key biome: it contains unparalleled biological diversity, a globally significant store of organic carbon, and it is a potent engine driving global cycles of water and energy. The importance of understanding how land surface d...
Projections of climate change effects on discharge and inundation in the Amazon...
Sorribas, Mino Viana; Paiva, Rodrigo C. D.; Melack, John M.; Bravo, Juan Martin; Jones, Charles; Carvalho, Leila; Beighley, Edward; Forsberg, BruceClimate change and its effects on the hydrologic regime of the Amazon basin can impact biogeochemical processes, transportation, flood vulnerability, fisheries and hydropower generation. We examined projections of climate change on discharge and inundation extent in the Amazon basin using the regional hydrological model MGB-IPH with 1-dimensional river hydraulic and water storage simulation in floodplains. Futu...
Modelo de otimização dos recursos hídricos para irrigação, conforme a época de ...
Costa, Marcos HeilCoordenação de Aperfeiçoamento de Pessoal de Nível Superior; Propôs-se desenvolver, neste trabalho, um modelo para o consumo de água para fins de irrigação com o objetivo de prever, por meio de simulação, o impacto que teriam diferentes épocas de plantio adotadas pelos irrigantes de toda uma bacia hidrográfica na vazão dos cursos d'água dessa bacia, na época mais seca do ano. O modelo desenvolvido resultados ob...
Nitrogen-use efficiency, nitrous oxide emissions, and cereal production in Braz...
Pires, Marcel Viana; Cunha, Dênis Antônio da; Carlos, Sabrina de Matos; Costa, Marcos HeilThe agriculture sector has historically been a major source of greenhouse gas (GHG) emissions into the atmosphere. Although the use of synthetic fertilizers is one of the most common widespread agricultural practices, over-fertilization can lead to negative economic and environmental consequences, such as high production costs, depletion of energy resources, and increased GHG emissions. Here, we provide an anal...