“NGOs don’t mobilise people, desperation mobilises people,” said a Cambodian land activist as he related the experience of Boeung Kak villagers who were driven off their land by their own government to make way for corporate profiteering.

Such stories were abundant from all corners of the world this week at the World Social Forum in Dakar, Senegal. The forum, which celebrated its 10th anniversary this year, attracted representatives from civil society organisations, social movements and unions from more than 123 countries. Present among them were land rights activists and small farmers, who came to relate and decry the unfettered grabbing of their land.

Land grabbing emerged as the hot topic in this year’s forum. The phenomenon is defined as taking possession of and/or controlling a scale of land for commercial or industrial agricultural production, which is disproportionate in size in comparison to the average land holding in the region. Stories from Madagascar, Democratic Republic of Congo, Mali, India, Brazil and Mozambique illustrate that the phenomenon is widespread and the consequences can be dire. Land investments from overseas to secure food supplies and biofuels, speculation and resource extraction are the major drivers of this phenomenon.

Speaking through a megaphone under a plastic tent, peasant leaders from Mali exposed the acquisition of plots in their village by the Libyan government, which built a 40-metre long canal through their community. The canal runs through their traditional pastoral grazing land, cultivated plots and even their cemetery. “Not even our dead could rest in peace,” said the representative from Afrique Verte, a local NGO monitoring the issue.

In a world where the commoditisation of resources has become the norm, it is not surprising that communities are losing their most precious assets to the highest bidder. The spectre of a hungry world is being used to push the agenda for industrial agriculture, but in reality, the majority of the land is used for producing animal feed and agrofuels, as well as land speculation, rather than food crops. A World Bank report on land acquisitions shows that only 37% of this land is used to grow food.

Land has become one of the hottest commodities in the world market, particularly in sub-Saharan Africa, where 70% of the global grabbing took place from 2006 to 2009, according to the World Bank. Buyers prefer land that is easy to acquire and fairly fertile, with access to water resources. As most governments desire foreign direct investment in the elusive pursuit of a narrowly defined “economic growth”, the optimal transaction almost always comes at the expense of small farmers. .

Small family farms are considered economically “inefficient” because their yields feed their communities and not the global market. But family farms actually have higher productivity per hectare than their larger counterparts. Nevertheless, investment in them has been reduced in the last 20 years in favour of industrial farming.

In my home country of Brazil, we have seen the disastrous effects of this large-scale agricultural development model, where half of agricultural production is going to soy and sugar cane, to feed animals and cars, not people. Brazil went from 8% to 35% of global trade in soy in the decade to 2005, but this comes at the cost of deforestation of the Amazon, displacement of traditional communities and a massive rural exodus to urban slums. Yet it is the small farmer that feeds Brazil, with 60% of the food consumed nationally coming from family farms, according to the 2006 Agricultural Census.

Inherent in this predicament is the commodification of land, which stems from the neoliberal development model that drives policymakers. The very architecture of this global governance and economic system must be challenged and reformed. The time has come to reinvest in the kind of agriculture that actually feeds people. The notion that small farmers are unproductive renders them invisible; their contributions to their communities and local development go unrecognised and with that they go on tightening their belts, one notch at a time.

Land rights activists here at the World Social Forum call for global agriculture to work for people, upholding the right to food, supporting land reform that recognises customary rights and invests in small-scale production. We demand that our governments assume their responsibility to us, their constituents. Our needs should drive their actions, not a quixotic quest for corporate investment returns that have little chance of feeding the world’s poor.

• This article was amended on 14 February 2011. In the sixth paragraph, “Africa” was corrected to “sub-Saharan Africa” and “International Food Policy Research Institute” was changed to “World Bank”, which was the source of the statistic. “The 90% increase in soy production in the last decade in Brazil comes at the cost of deforestation” in the eighth paragraph was changed to “Brazil went from 8% to 35% of global trade in soy in the decade to 2005, but this comes at the cost of deforestation”.