Hypothesis: Spatial variation in species richness is caused by increased maintenance metabolic costs that increase habitat overlap and decrease species richness. Organisms: Non-volant mammals in North America. Results: The latitudinal gradient in species richness could be completely explained by variation in maintenance metabolic costs. Additional spatial variation in species richness was posit...

Studies of grasslands on specific soil types suggest that different nutrients can limit biomass production and, hence, species composition and number. The Brazilian cerrado is the major savanna region in America and once covered about 2 million km(2), mainly in the Brazilian Central Plateau, under seasonal climate, with wet summer and dry winter. In view of the importance of soil chemical facto...

Studies of grasslands on specific soil types suggest that different nutrients can limit biomass production and, hence, species composition and number. The Brazilian cerrado is the major savanna region in America and once covered about 2 million km, mainly in the Brazilian Central Plateau, under seasonal climate, with wet summer and dry winter. In view of the importance of soil chemical factors ...

forest types mapping, is one of the most necessary elements in the forest management and silviculture treatments. traditional methods such as field surveys are almost time-consuming and cost-intensive. improvements in remote sensing data sources and classification –estimation methods are preparing new opportunities for obtaining more accurate forest biophysical attributes maps. this research co...

introduction: soil organic matter is influenced strongly by vegetation cover and management, therefore it is proposed as the main indicator of soil quality and health. the changes in soil organic matter status occur much more rapidly in the labile pools than in organic c. thus, labile pools can be used as early indicators of changes in total organic matter that will become more obvious in the l...