An ecological integrity assessment of a Brazilian Atlantic Forest watershed based on surveys of stream health and local farmers' perceptions: implications for management

While ecosystem services provide benefits at various spatial scales, often the decision to conserve an ecosystem lies with the local people. Knowing the perceptions of local landowners of the benefits provided by ecosystem services cannot only help in the design of efficient mechanisms for environmental conservation, but also in achieving the support of these mechanisms by the local stakeholders. In this article we use both standard scientific assessment and the stakeholders' local ecological knowledge in order to acquire information about both the ecological integrity of an Atlantic Forest watershed, and the ecosystem services it provides. In a small-scale case study of the Macabu River watershed in Brazil, we investigated and compared a rapid field assessment of stream ecological integrity with the stakeholders' local environmental perceptions as revealed through interviews. This comparison indicates that the farmers tended to overestimate the ecological integrity of the stream reaches located inside their properties. However, the farmers also showed ecological knowledge about the environment and forests' ecosystem services, such as the maintenance of water supply and suitable climatic conditions. Our results thus indicate that the farmers' perceptions about the environmental impacts and ecological integrity of forest and water are apparently more strongly influenced by direct uses and opportunity costs, representing a market failure of asymmetrical information. Such market failure could be overcome by more fully informing farmers about ecosystem services and possible direct economic advantages of riparian forests.