Trabalho EAD ECNONOMIA

VARIAÇÃO SAZONAL DE TEMPERATURA E UMIDADE EM SOLOS SOB FLORESTA, MANGUEZAL E PASTAGEM NA AMAZÔNIA.

José Ricardo Santos de Souza;(1)
Julia Clarinda Paiva Cohen; (1)
Regina Célia dos Santos Alvalá;(2)
Fábio Roberto de Miranda Costa; (1)
Luiz Alves dos Santos Neto; (1)
Sidney Figueiredo de Abreu (1)

ABSTRACT: Soil temperatures were measured, using thermistor sondes placed at 5, 20 and 50 cm depth, beneath mangrove, natural pasture and native forest areas, in eastern Amazonia. The Soils volumetric moisture contents, within the upper 30 cm layer, at the same pasture and forest sites, were also monitored by reflectometer probe sensor systems. The experimental sites were selected along a 500 km transect parallel to the equator, within a latitudinal zone, between 0 and 2 degrees south.
Incident radiation fluxes and precipitation were simultaneously monitored by automatic weather stations installed on towers, for this experiment. These data showed that, the climatic regimes at all three monitoring sites were similar and largely impacted by the arrival the ITCZ, which sets the transition between their local dry and rainy seasons.
Forty one months of data were analyzed to determine the monthly averages and hourly average behavior of the two soil physical variables mentioned above. The results show that, besides the seasonal variations of precipitation and incident radiation fluxes, which in large part control the soils moisture and temperature; the vegetation coverage of these ecosystems, plays an important role in the wide range of observed variability of their soils physical variables.

RESUMO: Temperaturas de solos foram medidas por sondas de termistores instaladas a 5, 20 e 50 cm de profundidade, sob áreas de manguezal, pastagem natural e floresta nativa, no leste da Amazônia. Os conteúdos volumétricos de umidade dos solos na camada de 30 cm de profundidade, nos sítios de pastagem e floresta, também foram monitorados, por sondas de reflectômetro. Os