The report writes answers this question on page 12:

Although poverty in urban areas is substantial and increasing, global poverty is still predominantly a rural phenomenon. Some 75 percent of the poor live in rural areas despite the global trend toward urbanization. Even in 20 years, 60 percent of the poor are expected to live outside of cities (IFAD 2001:15). Providing a route out of poverty for these rural residents will remain a priority for national governments and the international community for decades to come (Reed 2001:13; World Bank 2003:1).

In addition, while urban ecosystems such as parks, waterways, and green spaces provide important services, it is rural ecosystems that provide the bulk of the goods and services on which humans depend for survival. The forest areas, fisheries, grasslands, agricultural fields, and rivers that provision both urban and rural residents, be they poor or rich, exist primarily in rural areas, and this is where most ecosystem governance and management occurs. However, even as we focus on rural ecosystems and the rural poor, we recognize the intimate connection between the urban and rural spheres. Much urban poverty, for example, begins as rural poverty, exported from the countryside through rural-to-urban migration. Working for a healthier rural economy thus helps address urban poverty too, by lessening this migration. At the same time, the rural and urban economies are deeply intertwined, particularly through the flow of remittances from the city back to family members in the country. In fact, being able to tap into such remittances is often one of the dividing lines between poverty and sufficiency, and modern rural economies could hardly function without this net flow of income out of urban areas. In the end, then, we realize that addressing rural poverty has an important urban dimension as well. Urban and rural poverty can never be completely disentwined.

The article states:

Support is growing for the idea of linking aid with environmental protection. A new report proposes that enabling local communities to manage natural resources is the key to tackling poverty. In response, development experts are calling for a more scientific approach to deciding how aid money should be spent.
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One solution, suggests the report, is for development agencies to focus on wealth created when people work together to manage local ecosystems. During the past decade, for example, communities in Fiji have reversed a decline in marine catches by confining fishing to restricted areas. In northern Tanzania, land reforms helped villagers band together to succeed where overseas agencies had failed, reforesting around 3,500 square kilometres of badly degraded land that now provides fuel and food.

But the report includes few such successes. “If you tried to find 50 more you couldn’t,” says Lash. Organizations such as the World Bank do not consider the ‘ecosystem services’ that underpin the successful case studies, he says.

“That’s a correct and important point,” says Jeffrey Sachs, director of the Earth Institute at Columbia University in New York. If ecosystem services are not taken into account, he says, aid agencies go on supporting such schemes as fisheries that raise incomes in the short term but reduce community resources as fish stocks shrink.

Sachs adds that development agencies fail to involve researchers in schemes that focus on ecosystem services. “There is lots of good science available, but very little is tapped for public policy,” he says. “We have two cultures. Most people who have trained in economics are not trained in science.”

Scientific input, say the few researchers who have taken part, can help people see if changes are working and test out future options.

In KwaZulu-Natal, South Africa, for example, scientists helped local women design experiments to assess the ecological impact of different clam-harvesting strategies.

“The point is for scientists to help communities gather the information they need to manage their marine resources better, rather than telling them what to do,” says Bill Aalbersberg, an applied ecologist at the University of the South Pacific in Fiji, who helped communities monitor the impact of no-catch zones.

Some development agencies say they are taking the message on board. The UK Department for International Development, for example, last year appointed a chief science adviser and announced plans to increase its research budget by more than £50 million (US$90 million) to £135 million in 2007. It says it is working with environmental organizations such as the WWF to ensure that the work it supports involves local stewardship of natural resources.

Those people will move to urban areas and will get rich.