Vegetation and land-use effects on soil properties and water infiltration of Andisols in Tenerife (Canary Islands, Spain)

Andisols are soils with high structural development and aggregate stability, characteristics that play a major role in their high infiltration rate. They are, however, vulnerable to environmental changes, particularly those associated with land use modifications. The present work aims to ascertain the influence of modifications to land use as well as vegetation cover on the steady-state infiltration rate and associated properties of Andisols on the volcanic island of Tenerife (Canary Islands, Spain). Thirty two sites were selected in three categories of land use/vegetation cover (green forest, pine forest and cropped areas). The infiltration rate was studied using a double ring infiltrometer. Other soil properties which influence infiltration – organic matter content, texture, structure, bulk density, water retention capacity and water repellency – were also studied. Infiltration is extremely rapid under green forest (796 mmh− 1) but falls considerably under pine forest (188 mmh− 1) and in formerly cropped soils (67 mmh− 1). The statistical analysis shows that the main soil properties affected by a change in land use/vegetation and which determine infiltration are soil aggregation, structural stability and, to a lesser extent, organic matter and bulk density. Compared to the green forest sites, a notable reduction in soil aggregation, structural stability and organic matter, and an increase in bulk density, are observed in the formerly cropped soils. Although less pronounced, the same tendency is seen also in the pine forest sites when compared to their green forest counterparts. The results confirm the vulnerability of Andisols' soil properties and infiltration to land use modification, while also highlighting the influence of the type of forest cover present.

► We study the effects of land use/vegetation change on infiltration of Andisols.
► Under natural conditions Andisols have a high structure stability and infiltration.
► These soils are highly susceptible to changes in environmental conditions.
► Loss of and even change in forest covers leads to the decrease in infiltration values.
► This change is related in both cases to the drop in soil aggregation and stability.