Poisson boundary of the discrete quantum group

We identify the Poisson boundary of the dual of the universal compact quantum group Au(F) with a measurable field of ITPFI (infinite tensor product of finite type I) factors.

Salinisation in irrigated agriculture in Pakistan: mistaken predictions

This paper revisits data and information that was collected through field studies by the International Irrigation Management Institute (IIMI) in Pakistan in the early 1990s. Analysis of available data led in 1996 to the publication of an IIMI research report (Kijne, 1996) whose main conclusion was that current cropping intensities and groundwater usage in Pakistan's irrigated agriculture were not sustainable. Ten years on there is no evidence that this prediction came true and the paper questions why those predictions were wrong. Based on more recent field data and information, the water and salt balances for one of the experimental sites are recalculated. Reasons for the mistaken predictions include: lack of understanding of farmers' reactions to signs of salinity in their fields, insufficient knowledge of the actual groundwater usage and underestimating the leaching fractions. The difficulty in accurately determining the actual leaching fraction from easily measurable field parameters affects the prediction of salt accumulation in the soil. The conclusion that current practices are all right is conditional on maintaining sufficient downward fluxes in the soil profile. The paper ends with some general reflections on predictions for the future.