All 10 provincial governors of the island of Sumatra have agreed to a deal to protect endangered forests, a move that could help control planet-warming emissions, Indonesian authorities said at the World Conservation Congress in Barcelona. When trees in Sumatra are cut down or burned, the soils underneath are exposed, releasing carbon dioxide as peat oxidizes and decomposes. The peat is so deep and plentiful in parts of Sumatra that the prevention of forest clearing could make a significant contribution to lowering greenhouse-gas emissions, according to environmentalists. Hermien Roosita, Indonesia's deputy minister for the environment, said Thursday that the next steps would involve coming up/ with an islandwide conservation plan.