A seminar organized by the Nairobi Stock Exchange suggested that “sorghum, cassava, soy beans, palm oil and Jathropha curcas, are the five crops that will run agri-business this century.” Be afraid. Be very afraid.
The GlobWetland project uses remote sensing and GIS to address the threats faced by the world’s wetlands. Do we know how many crop wild relatives are found in wetlands? Or even how threats to wetlands affect genetic diversity in adjacent agricultural areas? I think plant genetic resources people and the ecosystem conservation crowd need to link up a bit more, and I can’t help thinking that wetlands might be pretty good meeting ground.
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?
The latest Nature has a paper on mapping endangered animal species in a couple of different groups and relating what might be called “extinction threat hotspots” to “biodiversity hotspots.” The paper is getting a lot of media attention, for example here and here. Perhaps not surprisingly, the two types of hotspots do not match up, so a focus solely on protecting biodiversity in the well-known global hotspots is perhaps not going to be as effective as one might wish. No word on whether someone is doing similar work on plants, but I wouldn’t be at all surprised if the results were to turn out similar. But what about crops? I can think up theoretical arguments why centres of genetic diversity of crops might also be at particular risk from genetic erosion, but as for empirical data the problem is that information on genetic erosion tends to be anecdotal and patchy.
According to this article, the number of date palms in Morocco has declined from 15 million at the end of the 19th century to 4.5 million now, mainly due to desertification. That has to have had some effect on genetic diversity, and I’m willing to bet there are data out there on the numbers of varieties at different times in the past.