Abstract

Agroforestry associated with water harvesting was evaluated in field experiments conducted in central Chile, 1996–2008. Soil fertility parameters, such as soil organic matter (SOM), soil reaction (pH), total nitrogen (NT), total phosphorus (PT) and total potassium (KT) contents were measured for five different treatments: control (C), agroforestry (A), agroforestry with water harvesting (AR), woody perennial (W) and woody perennial with water harvesting (WR). Acacia saligna was used as the woody perennial component. Treatments, including Acacia saligna (A, AR, W and WR) increased SOM and NT stocks over time compared with the control, probably due to higher SOM and N inputs from the litter and root turnover. The treatments with water harvesting (AR and WR) showed the highest SOM and NT contents by 2008, suggesting that this practice had positive effects on water infiltration rates and soil water content in the soil, important parameters in the process of root turnover. However, there were no significant differences in other soil parameters, such as pH, PT and KT, perhaps due to the short study time, and soil spatial and temporal variability between treatments.