How do plants that move and spread across landscapes become branded as weeds and thereby objects of contention and control? In a chapter recently published in the International Handbook of Political Ecology, Priya Rangan and I outline a political ecology approach that builds on a Lefebvrian understanding of the production of space, identifying three scalar moments that make plants into ‘weeds’ in different spatial contexts and landscapes.
Just rediscovered a scribbled note from a few days in the “brousse” of New Caledonia late last year. We visited landscapes pounded by grazing, from a 600 ha cattle station turned into a horse farm and gîte in the more wild, mountainous nickel mining country around Thio, to the yellow-grass cattle and goat ranches in the semi-arid rain shadow country of Boulouparis. In these places, I found myself in the company of a variety of familiar thorny and weedy plants like mimosa bush, lantana, and coffee bush. Different bouquets of the same suite of plants decorate pastoral landscapes I’ve encountered in Fiji, Vanuatu, Madagascar, Australia, Reunion… and probably many more places too.
Seeing these ‘old friends’ reminded me of a simple message about biological invasions that does not get enough consideration: it’s not the plant’ fault. The plants themselves – or the plant species – do not really deserve the lables as invasives and weeds. It is us humans that need to be branded: they are there because of us, because of our land uses and Read the rest of this entry »
The baobab, that iconic, majestic, and grotesquely massive roots-in-the-sky tree, teaches us something surprising about “nature”. It demonstrates that what appears to be “natural” has been – for millennia and millennia – also fundamentally “social”, for people have been important dispersal agents of these trees. Researchers like Chris Duvall and Jean-Michel Leong Pock Tsy have shown this for the African baobabs.[1,2] Our recently completed research project, led by Priya Rangan, demonstrates this in multiple ways around the Indian Ocean. Baobabs are such useful and remarkable trees , it is hardly difficult to imagine people not picking up the hard but pleasantly light and fuzzy fruit pods and walking with them.
One part of our project looked at the single species of baobabs found in Australia: Adansonia gregorii, called boab. It grows in the Kimberley region in the northwestern part of the continent. In a study just published in PLoS ONE , we combine evidence from baobab genetics  and Australian Aboriginal languages to show that humans have been the primary agents of baobab dispersal. In particular, we reveal their crucial role in dispersing baobabs inland from now-submerged areas of northwest Australia during the dramatic sea-level rises at the end of the last glaciation. (See also this article in The Conversation as well as Priya’s blog about the study)
A further question is how the baobabs arrived in Australia in the first place. Oceanic dispersal via seed pods floating in currents, several million years ago, remains the most plausible explanation, as our collaborator David Baum has shown . Yet, another one of our baobab collaborators (and veritable Renaissance man) Jack Pettigrew advances an interesting speculative argument about a possible human role in transporting the baobabs, building on evidence from rock art in the Kimberley and in Read the rest of this entry »
In just the span of a decade or two, it seems that nearly all environmental management writing (whether scientific reports, public awareness brochures, or policy briefs) has come to call on the notion of “ecosystem services” to defend the importance of healthy, functioning “natural” systems. What is this concept, where does it come from, what does it mean, and what doors does it open or close?
Is “ecosystem services” the ultimate win-win idea that translates abstract values of a healthy environment into policy-relevant and policy-actionable chunks? Does it allow ecologists and economists to speak the same language, leading to better outcomes for the environment and for the rural (often marginalised) people who manage it? Or is it a tool of the “neoliberalization” of nature, another means by which capitalism penetrates into new terrains, creating new forms of accumulation in the hands of a global elite, further marginalising the poor? Or is it all of this – and more – at the same time?
While a number of plants, animals, and insects in Madagascar have been called ’invasive’, the topic of invasive species has until recently received less attention here than in other island contexts. Some species, often alien to Madagascar and introduced by humans, have expanded their range rapidly and have had both negative and positive effects on landscapes, on native biodiversity, and on livelihoods. Examples include the prickly pear (raketa), the silver wattle (mimosa), and, recently, the Asian common toad (radaka boka). Building on a conceptual approach, my recent paper (link; pdf) in the journal Madagascar Conservation and Development emphasizes the importance of inclusive and deliberative site- and population- specific management of invasive species. The paper analyses three separate concepts commonly used in definitions of invasion: the origin, behaviour, and effects of particular species.
It places these concepts in their broader social and ecological context, with particular attention to local perspectives on invasive species. My co-authors and I illustrate these concepts with numerous Malagasy examples from the literature and our own experiences. Read the rest of this entry »
What role did slaves from Africa and Madagascar play in transporting, spreading, and cultivating new plants in the sugar colonies of Mauritius and Reunion? What can plant names teach us about the lives and landscapes of marginalized people in the past? Read the rest of this entry »
All good things must come to an end, and so it is with my time at the School of Geography and Environmental Science, Monash University, Melbourne.
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