Author: Luigi Guarino

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How fast will this climate change be anyway?

ResearchBlogging.orgWell, in terms of distance along the Earth’s surface, about 400 m per year on average, ranging from 80 m per year in mountainous regions to 1.26 km per year in deserts. That’s according to a new paper in Nature by Loarie et al. 1 Compare that with figures of postglacial migration rates of <100 m per year for some trees. Here’s a map of the speed of temperature change by biome from the Nature paper (click to enlarge).

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And here’s the “persistence time” for protected areas in different biomes, i.e. the diameter of protected areas divided by the climate velocity.

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The persistence time — which is how long it takes for the current climate to cross a protected area — exceeds 100 years for only about 8% of protected areas. And that, dear reader, is why we need protected areas that are larger and more connected. Oh, and genebanks.

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Indigenous vs exotic trees in Kenya

I promised to reveal a silver lining to the black cloud of my mother-in-law’s forced felling of part of the eucalypt plantation she’s been tending and coppicing forever, her main source of firewood, so here goes. The sight of the newly bare patch of land made her start looking around for a source of seedlings for replanting, and a coincidental visit by some old friends of mine got her thinking that maybe she should go indigenous. At least partly, anyway. Eucalypts are too fast-growing to give up altogether. Her visitors were Lex Thomson and Randy Thaman, who I worked with in the Pacific, and were in Kenya for the International Agroforestry Congress. They noticed a few Prunus africana trees around her place, and told her about its potential. Lex has since left a comment about this on an earlier blog post of mine.

Anyway, after some searching around, Hilda (for that is her name) came across Mr Douglas Ndirangu Kirichu’s nursery at a place called Lari Forest Station in Uplands Division, a short drive along a passable dirt road from her farm. Mr Kirichu runs the Kimotu Environmental Group. He has about a hundred people who collect seeds from the surrounding forest, which he then raises to seedlings and sells, for KSh 30 each (that’s about USD 0.50). Apparently there’s a law that a community can only graze their animals in the forest if they also have a nursery raising indigenous tree seedlings for replanting. So that’s what Mr Kirichu’s group does. To the tune of about 30,000 seedlings when we visited him. 2

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In addition to Prunus africana (mueri in Kikuyu), Mr Kirichu (that’s him on the left in the picture below) also has muna (Aningeria), mutamayo (Olea), mukoe (Dombeya), pondo and mukima (not sure what these are — maybe someone out there can help me?).

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So we bought a couple of each, of course. And Hilda got a dozen mueri to start off her plantation.

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And we planted them both up at the farm (thanks, GK!) and down in Nairobi. Maybe that made the holiday carbon neutral?

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Nibbles: Vavilov on couscous, Molecular studentships, Goat genetics, Svalbard Global Seed Vault, Sweet potato, New Agriculturist, Vietnam and CC, Liberian ag research, Cuisine

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Re-inventing the genebank. Not.

ResearchBlogging.orgJeffrey Walck and Kingsley Dixon 3 have a piece on genebanks in December’s Nature entitled “Time to future-proof plants in storage.” 4 It says some important things, but in a way that suggests that nobody has thought of them before, or has done anything about it, which I think needs to be countered. 5 The article is behind a paywall, alas.

Here’s the crux of Walck and Dixon’s beef.

At low temperatures, seeds can remain viable for hundreds if not thousands of years. Herein lies the problem: such seeds are literally frozen in time, a snapshot of the genetic diversity of a species at a particular point. Attempts to revive a seed in future habitats very different from those in which it developed could be doomed to failure. A germinating seed is genetically programmed to respond to a precise interplay of temperature and moisture that determines the climatic conditions in which it can best develop. In an environment that lacks the right temperature and moisture balance — which is likely to be disrupted by climate change — a seed will either fail to germinate or the seedling will perish soon afterwards (see Fig. 1).

What are their suggestions for getting around this problem? Here’s a summary:

    1. Harvest as much genetic diversity as possible, including at the edge of species ranges, and at different points in time. And harvest large quantities of seed whenever possible.
    2. Screen the plants for their adaptation to different environments. “For instance, subjecting seedlings to increased temperatures could allow the selection of those with higher heat tolerance.”
    3. Use climate models to identify areas where different populations will be best adapted. “…climate change will alter the home range of a species, so restorers can be sure to reintroduce seeds in places that will match their particular germination requirements.”
    4. “Policy-makers must get involved too: a comprehensive international agreement is required to coordinate the collection of genetic material, particularly for cross-border wild species.”

So, that would be collect properly, evaluate, match seeds to environments and put in place an international policy infrastructure. Doh! I really can’t see anything in that list that genebanks are not already trying to do. Can you? Maybe they’re not doing it as well as they might, and certainly the policy environment is still not ideal, but there’s surely nothing particularly new about these recommendations. Sure, it is always useful to remind a community about best practices, but it would have been nice to point out that genebank managers around the world know what these are, and are in fact trying to follow them.

If they had wanted to suggest something that isn’t already in place, why didn’t they mention the pressing need for a comprehensive global information system? Now that would be an improvement. And yes, we — and they — are working on it.

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Millions Fed

That’s the title of an IFPRI project funded by the Gates Foundation which aims to document success stories in agricultural development. We mentioned it here before, when it was just being launched. There are a couple of agrobiodiversity examples among the case studies, including maize in Africa, mungbean in Asia and diet diversification in Bangladesh.