Since 2007 The Natural Capital Project has worked in the Eastern Arc Mountains with an international team of scientists and policy experts to analyze threatened ecosystem services and develop measures to conserve their value to people. Valuing the Arc is a research and policy program working to improve knowledge of the ecosystem services provided by the Eastern Arc Mountains of Tanzania, of their contribution to human welfare, and to find solutions to managing these services in a sustainable way. In doing so, this research aims to provide critical information to policy-makers in Tanzania and contribute to the wider field of ecosystem services research.

The program of work, as a whole, is focused on quantifying, mapping and valuing the key ecosystem services that flow from the Eastern Arc Mountains. This comprises a number of modules:

The Eastern Arc is a chain of ancient mountains covered by rain forests and grasslands in Tanzania and Kenya. Scientists believe that the forest has survived on the Eastern Arc Mountains for over 30 million years, and were once connected to the forests of the Congo Basin and West Africa. Neighboring mountains are much younger, for example Kilimanjaro is estimated to be about 1-2 million years old.

At least 200 vertebrates are of conservation concern and around 500 plant species are strictly endemic to these mountains. These are mainly found in the forest habitats. Estimates suggest that more than 70% of the original forest cover has been destroyed and only about 4,000 sq km of forest remain on the mountains. Most of the forest has been lost in the past 100 years due to conversion to farmland, unsustainable timber harvesting and uncontrolled fires.

Conserving these forest habitats is very important for the global community and for the people of Tanzania. Most of the remaining forests are within government forest reserves. These government forest reserves are poorly funded and have few staff, however they provide the mainstay for conservation in the area. Since 1998 local people often supported by civil society organizations have been increasingly involved in the management of the Eastern Arc forests.

For further information see www.easternarc.or.tz and www.easternarc.org. Related Projects - Valuing Ecosystems in the Virungas Landscape The Albertine Rift Conservation Society (ARCOS) Network is using InVEST outputs to garner government and stakeholder support for ecosystem service and biodiversity conservation in the Virungas landscape, which covers significant areas of Uganda, Rwanda and Democratic Republic of Congo. Their project has involved quantifying and valuing ecosystem services and examining tradeoffs between a Business as Usual (BAU), Green, and Market-driven scenarios. In its next phase, project implementers will promote new incentives for conservation using economic valuations of important ecosystem services.

The ARCOS network promotes collaborative conservation action and information-sharing across the entire Albertine Rift, stretching through six countries in east and central Africa and housing thousands of unique plants and animals. Its work preserving key ecosystems has earned the organization a 2012 MacArthur Award for Creative and Effective Institutions.

Measuring, Modeling and Mapping Ecosystem Services in the Eastern Arc Mountains of Tanzania

Brendan Fisher, R. Kerry Turner, Neil D. Burgess, Ruth D. Swetnam, Jonathan Green, Rhys E. Green, George Kajembe, Kassim Kulindwa, Simon L. Lewis, Rob Marchant, Andrew R. Marshall, Seif Madoffe, P.K.T.