Emelie Healy of FAO’s Land and Water Development Division has a mailing recently on the PPGIS discussion list saying that FAO has updated their dams database of Africa by overlaying with Google Earth. There is an online interactive map on this page and you can download the data as well from the FAO’s GeoNetwork data downloading service by entering “dams” in the free text line. They have also recently updated their irrigated areas map. You can find maps of the latest data and an interactive map as well as downloads here. And speaking of water, more than half of the world’s lakes are facing serious problems caused by agricultural activities, according to a paper presented at the 11th International Living Lakes Conference. Which probably feeds back on agriculture in complicated ways. Anyway, I would guess that the effect of dams and new irrigation schemes on local wild biodiversity is usually negative, but is that necessarily always the case also for agro-biodiversity? I suspect so, but is there a possibility that at least sometimes existing crop genetic diversity is simply displaced a bit geographically or ecologically within the same general area and augmented by new crop genetic diversity adapted to the new conditions?