In what situations do the practices of small-scale family farmers lead to increased tree cover, particularly on a continent better known for land degradation and deforestation? Research on the “forest transition”, a pattern where net deforestation is replaced by a net gain in forest cover, has so far avoided much mention of Africa. In contrast, it is historically documented in western Europe, eastern North America, east Asia, and seemingly underway in parts of Latin America and Southeast Asia. This research tends to focus on factors such as economic modernisation, rural abandonment, urbanisation, or even globalisation as driving forces of the forest transition. Two recent studies I contributed to focus instead on Africa – one in West Africa, one in Madagascar – and on transitions brought about by rural farmers. Read the rest of this entry »
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. Read the rest of this entry »
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 »
Just launched: a new website called Trans-Plants that asks “what can we learn about humans through plant movements, weeds, and invasive aliens?” It is a joint venture between Priya Rangan, Christian Kull, and their collaborators on three ARC-funded research projects and on all the activities that have spun-off from there.
The thorny bush Lantana camara, with its attractive pink, yellow, and orange flowerlets, covers vast areas of forest understory, fallow lands, and hedges in the hilly mountains fringing the southern end of Karnataka state, India. These upland areas are also home to several marginalized cultural groups (‘scheduled tribes’, or ‘indigenous people’) as well as a diversity of wildlife – elephants, tigers, bears, gaur, three kinds of deer, monkeys, boars, wild dogs, leopards. On our recent scoping trip to the Biligiri Ranganaswamy Hills some four hour south of Bangalore, we discovered that there were at least three ways one could talk about the lantana situation, each following familiar tropes: as a story of invasion, of dispossession, or of creative redemption. Read the rest of this entry »
Oil palm gets all the attention, but what about acacia? Oil palm has become synonymous with deforestation in Indonesia and resulting losses of orang-utan habitat, increased carbon emissions, and unhealthy smoke haze. But equally large areas of peatland are being converted to pulp and paper plantations of tropical salwood wattles like Acacia crassicarpa and A. magnum, trees that now cover many millions of hectares in South East Asia. In Riau province, Sumatra, the two big pulp mills (operated by Asia Pulp and Paper [APP] and Asia Pacific Resources International Ltd [APRIL]) have around 75 and 45 per cent (respectively) of their pulp plantations located on peatland. The ways in which such forestry concessions have been granted and implemented have inspired dramatic protests: 28 residents of the Meranti Islands in Riau Province stitched their lips shut while demonstrating in front of government buildings in Jakarta (Jakarta Post; Transparency Int.). Read the rest of this entry »