Global warming and climate change in Amazonia: Climate-vegetation feedback and impacts on water resources

Abstract

the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) has resulted in an unprecedented international effort to understand the functioning of the vegetation of Amazonia and its interaction with the atmosphere and hydrosphere. As a result, Amazonia is now almost certainly the best studied major tropical forest region of the world, although our journey to a comprehensive understanding of the functioning of this system is only just beginning. Some of the key questions that LBA asked in relation to the vegetation and soils of Amazonia included the following: (1) How does the structure and functioning of Amazonian forests vary across the region; what factors drive this variation? (2) How much carbon is stored in Amazonian vegetation and soils; is this carbon store increasing or decreasing in response to contemporary environmental change? (3) How does the supply of nitrogen, phosphorus, and other nutrients affect Amazonian forests and the viability and sustainability of management practices after conversion of forest to other land uses? (4) How does Amazonian vegetation respond to seasonal, interannual, and long-term drought? (5) What role does Amazonia play in global climatic teleconnections and in the budgets of the major atmospheric trace gases? (6) How are Amazonian forests changing, and how will they change in response to climate change? In this introduction, we provide a brief overview of the major themes discussed in this section. We do not introduce the chapters in sequence but rather when appropriate to our narrative.