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The objective of this paper was to identify key site effects on the productivity of Eucalyptus grandis, Eucalyptus dunnii, and Pinus taeda. Forest management units, characterized by similar productivity levels, were identified through chemical and physical soil attributes. Site index and soil data were collected from 27,690 ha afforested area located in Paraná State, Brazil, where soils and vegetation were statistically evaluated. Eucalyptus dunnii site index was the most related to soil attributes. The main factors affecting productivity were pH, clay content, organic matter, and exchangeable P. As for Eucalyptus grandis, productivity was affected by clay and organic matter content. Nevertheless, base saturation affected site index in sandy soils. Pinus taeda productivity was determined by potassium, cation exchange capacity, base saturation, and clay content. The same analysis carried out under a higher mean annual rainfall in Pinus taeda stands provided management units of higher productivity. The consideration of rainfall condition as a stratification criterion in the statistical analyses allowed minimizing the site index variation within each management unit. The results provide support for defining management systems as well as carrying out feasibility studies on species change and land purchase. [ABSTRACT FROM AUTHOR]

This paper presents an approach for estimating aerosol absorption by combining MODIS and MISR data. The approach uses a previously published concept based on combining clear and hazy days to retrieve aerosol absorption. It augments the existing approach by using multi-sensor data to improve the surface characterization and aerosol property retrieval. MODIS data are used to retrieve the aerosol optical thickness, whereas MISR data are first used to determine the surface properties on the clear day, and then to retrieve aerosol absorption on hazy days by using the derived surface properties as the ground boundary condition. The method is applied to two extreme cases of absorption in biomass burning situations: One case over Mongu (South Africa) and the other over Alta Floresta (Brazil). The range of single scattering albedo retrieved values is from 0. 7 to 0. 95. A comparison with AERONET independent estimates shows very good agreement (better than 0. 02 on average) across the whole range. [Copyright &y& Elsevier]