The past decade has seen a scramble among governments, trans-national corporations and private investors to negotiate expansive claims, leases and deals on land around the world for agricultural cultivation, grazing, timber, water, mining and industry. Investigative journalists and NGOs began reporting on these activities with particular urgency after 2008, when a spike in food prices triggered a rush for agricultural assets.
‘Land grabbing’ is the term for abrupt changes in rights to, and use of, large geographical areas. Counter-investment for environmental conservation has been dubbed ‘green grabbing’. Variants extend to economic zones in the oceans.
Associated with resource discoveries, territorial disputes, frontier expansion and colonialism throughout history, land grabbing is hardly new. What is new is the speed at which the technologically enabled grabbers are changing entire landscapes – particularly in places where industrial agriculture is established in environments that, if not untouched by humans, have co-evolved with social and cultural practices over time.
Land grabs that initiate wholesale shifts to extractive resource uses are capable of catalysing unnaturally rapid – and in many cases, irreversible – environmental transformations across vast spatial scales. Take, for example, the Dust Bowl catastrophe around the turn of the 20th century, which stripped topsoil from across the US Midwest following a government-sponsored derby for homestead land to encourage settlement and conversion of the Great Plains to agricultural production.
Scale is one trait that puts land grabbing on a par with geoengineering, a term typically defined as an intentional alteration to planetary-scale processes. Geoengineering is synonymous with technological responses to global warming that either remove carbon dioxide from the atmosphere or reduce the amount of solar radiation the Earth absorbs. But geoengineering can also include human activities that intentionally modify such large areas that, cumulatively, those activities unintentionally affect how the Earth’s natural systems function.
‘Mega-projects’, from the Panama Canal and the Dutch Delta Plan to the Three Gorges Dam, are examples of individual, strategic geoengineering interventions. But many modifications are the collective result of otherwise unorganised activities. Consider the global effect that small and medium-sized dams have had on catchment hydrology, river ecology and the pathways by which terrestrial sediments eventually reach marine sinks. Another example is evident in the mechanised and chemical agricultural practices of the Green Revolution, which continue to co-opt land cover, nutrient fluxes and energy demands.
This spectre of unintended consequences is something else that land grabbing and geoengineering have in common. Climate geoengineering raises fundamental questions regarding the risks, unknowns and ethical concerns associated with altering the Earth’s atmosphere. These include the non-local effects of local actions, time lags between when an intervention occurs and when its repercussions manifest, challenges in deriving regional predictions from global trends, and the broad ramifications of potentially unilateral decision-making.
The quandaries associated with land grabbing are similar. Research shows that agriculture, deforestation, ex-urban development and mining affect the systems that shape the Earth’s surface, but in ways that make future systemic changes – and geopolitical responses to those changes – difficult to predict.
It isn’t so far-fetched to suggest that grabbed landscapes might ultimately exhibit their own chemical and stratigraphic signature in the geology of the Anthropocene. In terms of mass per year, humans move a greater quantity of earth material – rocks and dirt – through agriculture and land clearing, mining and highway and housing construction than the combined quantity moved by rivers, glaciers, hill slopes, wind and waves. What’s more, the amount we move has increased exponentially over time.
Sedimentary evidence suggests that there have been three global pulses of soil erosion synchronous with agricultural expansion – during the second millennium BCE, between the 16th and 19th centuries, and after the Second World War. Yellow River sediments in China reflect episodic population booms, frontier surges and agricultural intensification over four millennia. Increased sediment load from land uses in Spain during the classical empires pushed the Ebro Delta seaward into the Mediterranean. Cores from marshes and estuaries in the northeastern USA show a spike in sedimentation rates concurrent with colonial-era deforestation.
If we want to gain insights into Earth’s future, we need to understand better how our manipulation of its surface functions as a geomorphic force.
This story was published in the July 2014 edition of Geographical Magazine