Resumen

CARVAJAL, Andrés F; FEIJOO, Alexander; QUINTERO, Heimar  y  RONDON, Marco A. Soil Organic Carbon in Different Land Uses of Colombian Andean Landscapes. R.C. Suelo Nutr. Veg. [online]. 2009, vol.9, n.3, pp. 222-235. ISSN 0718-2791.  doi: 10.4067/S0718-27912009000300005.

The relationship between changes in land use and soil carbon and nitrogen was assessed in Alcalá (Colombian coffee growing region), between 900 and 1600 m. Soils are Argiudolls and Melanudands and sampling units were defined according to the altitudinal gradient. Carbon and nitrogen content, C:N ratio, bulk density and 13C and ¹⁵N abundances were measured. Significant differences (p < 0.05) were found due to altitude effect, differentiating the high zone by high C (37.06 -42.88 t ha^-1), N (3.12-3.86 t ha^-1) and C: N (11.17-11.97), low bulk density (0.56-0.65 g cm^-3) and ¹⁵N abundance (4.59-5.15 %o). Fallow and monocultures stored more carbon in deeper layers of the soil, while most preserved sites showed low C, N contents. The ¹³C in land uses ranged between -25.18%o and -21.17 %o, indicating that carbon was fixed mainly by C₃ plants. It was concluded that land use changes affect C stocks, due to practices like chemical fertilization; and Alcalá soils have high potential for ecosystem services related with edaphic carbon capture.

Palabras clave : carbon sequestration in the Andes; land use changes; stable isotopes.