Effects of land-use change on some properties of tropical soils — An example from Southeast Mexico V. Geissen a, ⁎, R. Sánchez-Hernández a,c , C. Kampichler b , R. Ramos-Reyes a , A. Sepulveda-Lozada a , S. Ochoa-Goana a , B.H.J. de Jong a , E. Huerta-Lwanga a , S. Hernández-Daumas a a El Colegio de la Frontera Sur, Unidad Villahermosa,Tabasco, Mexico b Universidad Juárez Autónoma de Tabasco, Div. Acad. De Ciencias Biol, Mexico c Universidad Juárez Autónoma de Tabasco, Div. Acad. De Ciencias Agropecuarias, Mexico abstract article info Article history: Received 22 May 2008 Received in revised form 19 January 2009 Accepted 17 March 2009 Available online 28 April 2009 Keywords: Land use Tropical soils Organic carbon Acidity Nutrients Soil compaction We studied the effects of land-use and land-cover changes on physical and chemical properties of soil in tropical South-East Mexico. In the study area of about 5500 km 2 , the dominant land use is pastureland (Pa seasonal agriculture (TA), fruit plantations (FP), sugarcane, (SC) secondary (SF) and primary forest (PF) and other not specified land-use types (undefined). From 1988 to 2003 severe deforestation took place and pastureland increased by 179% while primary forest decreased to 17% of the initial area. Based on topographic and soil maps we selected 176 sampling sites covering the combinations of topography and soil type. In 2005, we took soil samples in each selected site from two soil depths (0–20 cm and 20– 40 cm). We analyzed fertility parameters like pH, texture and contents of organic carbon, total nitrogen and available phosphorus. Furthermore, we measured soil resistance against penetration in layers of 5 cm down to a depth of 40 cm. We estimated land-use changes between 1988 and 2005 using digital land-use maps derived from satellite and aerial photography interpretation. We compared soil properties of different soil types, soils under different current land use and under the influence of land-cover changes. Gleysols, Vertisols, Regosols, Luvisols and Leptosols showed clay to clay loam texture, whereas Cambisols were characterized by sandy clay loam texture. All soil groups in the study region were slightly acidic with pH (KCl) values between 5.3 and 6.2. Furthermore, they neither showed significant differences in available P content nor in C/N ratio. However, the investigated soil associations displayed different organic carbon and total nitrogen contents in the upper 20 cm depth. Soils under different current land use did not show any significant differences with respect to available phosphorus, organic carbon, total nitrogen and C/N ratio whereas the pH value was significantly higher under seasonal agriculture than under pasture. Land-use changes between 1988 and 2003 did not significantly influence the contents of available phosphorus and organic carbon or the C/N ratio. However, total nitrogen was significantly higher in soils which were changed from forest in 1988 to seasonal agriculture in 2003 (F-TA) than in soils changed from forest to pastureland (F-Pa) or from pasture to forestland (Pa-F). Furthermore, soils under land-use change F-TA were less acidic in both depths than soils under Pa-F, TA-Pa, or which remained pastureland over the whole time (Pa-Pa). Soils in pastureland were significantly more compacted in all layers than soils used for seasonal agriculture. Soils that were used for pastureland already in 1988 showed significantly higher compaction than most of the other soils. We conclude that land-use change in a period of 15 years did not lead to chemical soil degradation. However, permanent pastureland leads to a severe compaction of soils. © 2009 Elsevier B.V. All rights reserved. 1. Introduction In the last decades severe land-use changes occurred in tropical countries, due to increasing population and their demand for food resources (Houghton et al., 1991; Houghton, 1994; Ojima et al., 1994; Lambin et al., 2001). Forest land is rapidly converted into agriculture or pastureland. Land-use conversion may cause important changes in soil physical and chemical characteristics and can affect soil fertility, increase soil erosion or cause soil compaction (Neill et al., 1997; SEMARNAT, 2002a). The effect of the conversion of forest land into pastureland on soil organic matter is variable, in some cases an increase has been reported for certain locations (De Moraes et al., Geoderma 151 (2009) 87–97 ⁎ Corresponding author. E-mail address: vgeissen@web.de (V. Geissen). 0016-7061/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.geoderma.2009.03.011 Contents lists available at ScienceDirect Geoderma journal homepage: www.elsevier.com/locate/geoderma