Forest-to-pasture conversion influences on soil organic carbon dynamics in a tropical deciduous forest
Por:
García-Oliva F., Casar I., Morales P., Maass J.M.
Publicada:
1 ene 1994
Resumen:
On a global basis, nearly 42% of tropical land area is classified as tropical deciduous forest (TDF) (Murphy and Lugo 1986). Currently, this ecosystem has very high deforestation rates; and its conversion to cattle pasture may result in losses of soil organic matter, decreases in soil fertility, and increases in CO2 flux to the atmosphere. The soil organic matter turnover rate in a TDF after pasture conversion was estimated in Mexico by determining natural abundances of13C. Changes in these values would be induced by vegetation changes from the C3 (forest) to the C4 (pasture) photosynthetic pathway. The rate of loss of remnant forest-soil organic matter (fSOM) was 2.9 t ha-1 year-1 in 7-year-old pasture and decreased to 0.66 t ha-1 year-1 by year 11. For up to 3 years, net fSOM level increased in pastures; this increment can be attributed to decomposition of remnant forest roots. The sand-associated SOM fraction was the most and the silt-associated fraction the least depleted. TDF conversion to pasture results in extremely high rates of loss of remnant fSOM that are higher than any reported for any tropical forest. © 1994 Springer Verlag.
Filiaciones:
García-Oliva F.:
Centro de Ecología, Universidad Nacional Autónoma de México, AP 70-275, México, CP 04510, D.F., Mexico
Casar I.:
Instituto de Física, Universidad Nacional Autónoma de México, CP 04510, México, AP 20-364, D.F., Mexico
Morales P.:
Instituto de Física, Universidad Nacional Autónoma de México, CP 04510, México, AP 20-364, D.F., Mexico
Maass J.M.:
Centro de Ecología, Universidad Nacional Autónoma de México, AP 70-275, México, CP 04510, D.F., Mexico
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