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Chlordecone was applied between 1972 and 1993 in banana fields of the French West Indies. This resulted in long-term pollution of soils and contamination of waters, aquatic biota, and crops. To assess pollution level and duration according to soil type, WISORCH, a leaching model based on first-order desorption kinetics, was developed and run. Its input parameters are soil organic carbon content (SOC) and SOC/water partitioning coefficient (K(oc)). It accounts for current chlordecone soil contents and drainage water concentrations. The model was valid for andosol, which indicates that neither physico-chemical nor microbial degradation occurred. Dilution by previous deep tillages makes soil scrapping unrealistic. Lixiviation appeared the main way to reduce pollution. Besides the SOC and rainfall increases, K(oc) increased from nitisol to ferralsol and then andosol while lixiviation efficiency decreased. Consequently, pollution is bound to last for several decades for nitisol, centuries for ferralsol, and half a millennium for andosol.

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means, electronic or mechanical, including photocopying, recording, or any informa on storage and retrieval system, without permission in wri ng from the publisher. S S : V Z M Water fl uxes in the subsurface of forested and agricultural ecosystems vary spa ally across wide ranges because of several interconnected phenomena. On the one hand, subsurface environments are o en highly heterogeneous. On the other hand, infi ltra on water is o en distributed unevenly due to aboveground intercep on and redistribu on of rainfall by the plant canopy. These phenomena have important hydro-ecological consequences because they signifi cantly aff ect groundwater recharge and nutrient leaching. Field experiments involving subsurface lysimeters and tensiometers were performed to quan fy the spa al distribu on of fl uxes in an Andisol under a banana plant (Musa acuminata Colla).Wick lysimeters were installed at a depth of 70 cm at several loca ons with respect to the banana stem to measure the spa al distribu on of subsurface water fl uxes. Collected experimental data were simulated using the HYDRUS so ware package, which numerically solves the Richards equa on describing three-dimensional variably saturated water fl ow in the subsurface. Spa ally distributed drainage fl uxes were well reproduced with the numerical model. Due to the impact of stemfl ow, drainage volumes under the banana stem were up to six mes higher than in the row downstream from the stem, as well as between rows, as these areas were sheltered from direct rainfall by the banana leaves and received only throughfall.