Category: GIS

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Dams, lying links, and databases

A post on e-agriculture about information resources related to water in agriculture allows me to update, on the occasion of World Water Day, a piece we had here some years back. The links in that old post of ours no longer point to the things they used to, but if readers are still interested in that African dams database they can now find it elsewhere. Alas, I couldn’t get the Google Earth file to work, but if you do the work-around from the Excel file you get the map below. I’ll reiterate my original questions, to which I have no better answer now than four years ago, alas:

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?

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Training manual for GIS analysis of agrobiodiversity data

Great to see “Training Manual on Spatial Analysis of Plant Diversity and Distribution” finally out, courtesy of Bioversity International. Well worth the wait, and not just because I get called a pioneer in it. Congratulations to Xavier Scheldeman and Maarten van Zonneveld for addressing a very important need.

This manual has been published as a result of the increasing number of requests received by Bioversity International for capacity building on the spatial analysis of biodiversity data. The authors have developed a set of step-by-step instructions, accompanied by a series of analyses, based on free and publically available software: DIVA-GIS, a GIS programme specifically designed to undertake spatial diversity analysis; and Maxent, a species distribution modelling programme. The manual does not aim to illustrate the use of each individual DIVA-GIS and Maxent command/option, but focuses on using GIS tools to help answer common questions relating to the spatial analysis of biodiversity data. Throughout the manual, the importance of proper sampling is stressed; however, it is beyond the scope of the document to elaborate on sampling theories. The manual also does not discuss the statistical analysis of diversity data in detail; instead, when statistical methods and programmes are mentioned in the text, the reader is referred to alternative reference materials for further information.

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Yemen spatial data online, sort of

For what it’s worth, I have enormous admiration for IFPRI and its products. Not that they give a damn about that, but I just want to get it out of the way before slamming them. First, the news item on a new interactive atlas of food security in Yemen doesn’t have a link to the new interactive atlas of food security in Yemen. Not to worry, though, Google is your friend, ((Especially if they grant you a Google Earth pro license. Thanks, guys!)) and it’s not all that difficult to find the relevant page on the IFPRI website. But then the new interactive atlas of food security in Yemen turns out to be nice enough as to content, but highly frustrating to use. No way to download or export maps. I had to get the thing below (showing barley cultivation, for the record) through a screen grab. Yuch.

And no way to mash up the results with other stuff. Like, for example, barley accessions in Genesys. Which in contrast you can export in a number of ways.

Oh, sure, there are some words of explanation, if not excuse:

The online version does not require installing software but it is more limited in the sense that the underlying data cannot be accessed by the user (unlike in the case of the download of the data package).

But I don’t believe it would be that difficult to allow some sort of exporting online. Maybe I’m wrong. Someone tell me, please.

So, anyway, two maps which cry out to be looked at together, for example in Google Earth, and no way of doing so, at least that I can see. As I say, very frustrating. Who do I complain to? There someone in the CGIAR to whom I can go with a query about spatial data, right? Isn’t there?

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