The world's tropical forests are experiencing
unprecedented rates of clearing and conversion of various forms of
land use.1 Altered cycles of water, energy, carbon and
nutrients, resulting from the changes in Amazonian vegetation cover,
are expected to have climatic and environmental consequences at
local, regional, and global scales.
burned hillside, Santarém, November 1997
photo by D. Deering
To understand these consequences,
enhanced knowledge is needed of the natural forest systems
as well as systems which have already been converted to
various other forms of land use or secondary re-growth.
To this end, the Brazilian scientific community
called for a new multidisciplinary research effort in the early
nineties. A large number of South American, North American and
European research programs, agencies and individual groups have
contributed extensive efforts toward defining an integrated research
program in Brazil.
The Large Scale Biosphere-Atmosphere Experiment in
is an international research initiative led by Brazil. LBA is
centered on two key questions:
How does Amazonia currently function as a regional entity?
How will changes in land use and climate affect the
biological, chemical, and physical functions of Amazonia,
including the sustainability of development in the region and
the influence of Amazonia on Global climate?
The broad goal of the ecological research program is to improve
our understanding of the effects of tropical forest conversion on
ecosystem function and the sustainability of land use. The LBA-ECO
science question that focuses this study is:
How do tropical forest conversion, re-growth, and
selective logging influence carbon storage, nutrient dynamics,
trace gas fluxes, and the prospect for sustainable land use in
The main science objectives that will be used in answering this
question are as follows:
To quantify, understand and model the physical, chemical and
biological processes controlling the energy, water, carbon,
trace gas, and nutrient cycles found within Amazonia and to
determine how these link to the global atmosphere.
To quantify, understand and model how the energy, water,
carbon, trace gas and nutrient cycles respond to deforestation,
agricultural practices and other land use changes, and how these
responses are influenced by climate. As well as to predict the
impacts of these responses both within and beyond Amazonia under
future scenarios of changes in land use and climate.
To determine the exchanges of key greenhouse gases and species
regulating the oxidizing potential between Amazonia and the
atmosphere, and to understand the processes regulating these
To provide quantitative and qualitative information to support
sustainable development and ecosystem protection policies in
Amazonia, in the context of both its regional and global
In LBA, emphasis is given to observations and analyses that will
enlarge the knowledge base for Amazonia in several general areas:
1. Physical Climate
2. Carbon Storage and Exchange
3. Atmospheric Chemistry
4. Land Surface Hydrology and Water Chemistry
6. Land Use and Land Cover
7. Human Dimensions
The LBA-ECO Science Team is pursuing an integrated approach
involving synthesis of past results and data sets, modeling, remote
sensing, Geographic Information System (GIS)-based analyses, new
field observations and process studies, training and education and
synthesis and integration of new results in order to tackle the
LBA-ECO science question.
The results produced by the LBA-ECO Science Team will provide a
new understanding of environmental controls on flows of energy,
water, carbon, nutrients, and trace gases between the atmosphere,
hydrosphere, and biosphere of Amazonia. The results will also
provide a scientific basis for the implementation of policies
regarding the sustainable use of Amazonian natural resources.
1The LBA Science Planning Group. 1996. The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA):
Concise Experimental Plan. (17M pdf) SC-DLO, Wageningen, Netherlands. 44 p.