Governments from around the world will arrive in Nagoya, Japan next week for the high-level ministerial segment of the Convention on Biological Diversity (CBD) meeting. Their task is daunting. Even the modest target set in 2002 of reducing the rate of biodiversity loss by 2010 has proved beyond the reach of current strategies. But rather than wringing their hands over the tide of species loss that has swept the planet, delegates should turn their attention to the root cause of the problem: the ways in which we meet our need for food.

What does food supply have to do with conserving species? Everything. It is a leading factor in the five principal pressures causing biodiversity loss (habitat change, overexploitation, pollution, invasive species and climate change).

While producing food relies on harvesting nature's bounty, food production often degrades the very ecosystems it depends on. The Brazilian Amazon, for example, provides critical water and climate regulation services that the region's agricultural sector depends upon for its survival. Yet one-fifth of the Brazilian Amazon has been deforested, primarily by farmers and ranchers.

Delegates at the conference face a paradox. Dramatic increases in food production over the past 50 years have supported significant improvements in human wellbeing, but at the same time have diminished Earth's diversity and capacity to provide ecosystem services (including fish, food, freshwater, pollination, and water regulation).

The Amazon, for example, could reach a tipping point due to deforestation, where it dies back and changes into savanna-like vegetation. The reduction in rainfall would devastate efforts to raise crops and cattle in the region.

Adding to the challenge, population growth and rising per capita incomes are expected to double the demand for food in the next 40 years, according to the UN's food and agriculture chief, Jacques Diouf. To devise a successful new strategy to preserve the diversity of life on Earth, the CBD needs to take a quantum leap in its partnership with food producers, to change how the world achieves food security, before ecosystems reach critical tipping points in the face of ever growing demands for food and a changing climate.

The new 2020 global biodiversity strategy under discussion at Nagoya must focus first and foremost on reducing the pressure of food production on biodiversity and ecosystems. Three key strategies can help meet the goal of maximising use of existing land for food and minimising further ecosystem loss.

• Restore degraded lands

Globally, over 1bn hectares of land is believed to have restoration potential. Restoring even a small part of this for food production would help reduce pressure on natural ecosystems. In Indonesia, for example, the World Resources Institute (WRI) is seeking to develop a scalable model for diverting new oil palm plantations that would otherwise replace virgin forests on to degraded land.

• Increase productivity on existing farmland

While intensification doesn't immediately come to mind when thinking about conservation, it is nevertheless a key strategy to reduce stress on natural ecosystems. We need to deploy proven technologies that use ecosystem services much more efficiently such as new varieties of seeds, drip irrigation, integrated pest management and conservation agriculture.

• Manage demand for food

Opportunities for managing demand for food include promoting the use of vegetable protein over meat, reducing food waste – estimated to be around 40% of food produced in the United States – and advancing certification programmes and other types of incentives for sustainable food production. For example, Fairtrade is paying Afghan farmers almost double the going rate for providing raisins that meet environmental criteria such as the sustainable use of water – and making a viable business of it.

The proposed 2011-2020 strategic plan that ministers will be discussing in Nagoya does include some targets to address the destructive impacts of food production - such as reducing pollution from nutrient run-off and promoting sustainable farm management. But a much greater and more holistic effort is needed. Too much of the strategy takes a "remove-the-impacts" approach, a recipe for repeating the disappointment of not meeting the 2010 targets to reduce biodiversity loss.

If, by 2050, the world celebrates success in providing food security and in navigating ecological tipping points, it will be because of the ingenuity of farmers and conservationists, agricultural experts and ecologists in finding ways of learning and acting together.

• Janet Ranganathan is vice-president for science and research at the WRI. Frances Irwin is a former associate in WRI's institutions and governance programme