Hindawi Publishing Corporation ISRN Soil Science Volume 2013, Article ID 348905, 12 pages http://dx.doi.org/10.1155/2013/348905 Research Article Carbon and Water in Upper Montane Soils and Their Influences on Vegetation in Southern Brazil M. B. Scheer, 1,2 G. R. Curcio, 2 and C. V. Roderjan 3 1 Research and Development Assistance (APD/DMA), SANEPAR, Curitiba, PR, Brazil 2 Brazilian Agricultural Research Corporation (Embrapa Florestas), Colombo, PR, Brazil 3 Federal University of Paran´ a (UFPR), Curitiba, PR, Brazil Correspondence should be addressed to M. B. Scheer; mauriciobs@sanepar.com.br Received 25 November 2012; Accepted 3 January 2013 Academic Editors: P. Conte and W. Ding Copyright © 2013 M. B. Scheer et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Considering the many environmental functions of the upper montane soils, the aims of this study were (1) to verify if the soils of upper montane forests and grasslands of Caratuva Peak (1850 m a.s.l.) have similar characteristics to those found in other highlands in southern and southeastern Brazil; (2) to reinforce the geomorphological and pedological factors that impose the establishment of each type of vegetation in these highlands; and (3) to estimate potential soil carbon stocks and potential soil water retention. Folic and haplic histosols were found in the grasslands, and dystrophic regosols were found in the forests. Te soils were dystrophic, extremely acidic, and saturated with Al and total organic carbon. In contrast to the grasslands, the upper montane forests were prevalent in valleys and subjected to morphogenetic processes resulting in soils that contained thicker mineral horizons. Te grasslands occupied ridges and divergent convex ramps, and the pedogenetic processes in these regions promoted thicker histic horizons. Te potential water retention capacities were high and strongly related to the high porosities of histic horizons associated with the gleyic horizons. In particularly, the carbon stocks were two- to three-fold higher than those found in soil ecosystems from the same latitude but lower altitude. 1. Introduction Soil organic matter, which accumulates to a depth of 1 meter, weighs approximately 1500 × 10 15 g (Pg = petagrams) and constitutes the majority of continental organic carbon [1, 2]. Considering the soil surrounding native vegetation, Brazil stocks 5% of the global carbon reservoir [1], indicating that a single country can signifcantly infuence global carbon fuxes [3]. According to published studies [4–7], stock levels of below ground carbon increase concomitantly with higher altitudes. In southern Brazil, carbon stock levels of isolated soils can be two to three-fold greater in high altitudes compared to low altitudes from the same latitude [7]. Since the upper montane soil horizons include histic and humic horizons, they play an important role in the immobilization of carbon and regulation of hydric fuxes [8– 10]. Te vast accumulation of organic matter in these environ- ments originates from a lack of decomposition by microbes owing to unfavorable conditions, such as low temperature, high humidity, low respiration, lack of available nutrients, and high exchangeable Al concentrations [9–11]. Moreover, the organic matter is highly humifed and forms relatively stable organometallic complexes, predominantly with Al and Fe that serve as poor substrates for decomposition by microorganisms [9, 11–13]. Te humic substances contribute to the sustainability of these ecosystems by increasing their nutrient contents and increasing their capacity for cation exchange and water reten- tion. In turn, the ecosystem recycles carbon matter through above- and below-ground litterfall of developing vegetation [9, 10]. During rainy periods, the upper montane soils mini- mize erosion by becoming waterlogged and draining slowly; thus, regulating the hydric fuxes to the headwaters of the river basins [10, 14, 15]. In dryer periods, upper montane soils collect water from horizontal precipitation (water present in clouds) that commonly occurs in upper montane forests