Document: RUI-3-69-40

Soil responses to land-use change on Citlaltepetl Volcano, Mexico.

RUIZ-FONT, A.* ^1,2, L.VILLERS-RUIZ ² and M.A.ROJAS-VILORIA ²

CICATA-IPN, Puebla, México. ¹
UNAM, México, D.F., México ²
UNAM, México, D.F. , México ³

Abstract:
This work evaluated the land use changes and the soil chemical differences in western slope Citlaltepetl volcano (5610 m) forests, specifically in the area between 2500 and 4000 m. The vegetation is coniferous forest (fir and pine) and mixed forest (oak-pine). Agricultural use is mainly rain-fed corn, potato and bean crops. The forest cover was reduced by 1,044 ha (2.2% per year)over a 20 year-old period (1975-1995), in an area extended of 50,000 ha. Forest vegetation was selectively sampled using field plots of 500 m². The physical-chemical horizon "A" properties in forest soil (fir, pine and mixed forest) and the agricultural soils which had been forests, were assessed. The greatest decrease in organic matter (60% lost) occurred in agricultural soils formerly covered by fir forest. The least affected agricultural soils were formerly mixed forest (27% decrease in organic matter). Total nitrogen was most reduced in previously mixed forest agricultural fields (45% loss), while previously pine forest agricultural soils lost only 35% total N. Significant differences in the physical-chemical properties were observed between forests and agricultural soils resulting from the impact of land use changes.

Keywords: Citlaltepetl volcano Mxico; land use change; agricultural and forest soil properties

This abstract is being presented at: 3:30 PM in session:
AGROECOLOGY