1. What is the problem/issue being addressed?
The ALPHA (Assessing Legacies of Past Human Activities) project assesses how human activities and land use practices that have occurred over the past hundreds or thousands of years result in changes in that persist in the landscape and are manifested in modern forests. We are particularly focused on Amazonian rainforests, which were previously thought to be pristine and have a light human footprint prior to European arrival to the American continent in AD 1492. Archaeological data collected over the past several decades have shown that this is not the case. In some regions of Amazonia, indigenous people had complex and thriving societies. They were modifying soils, cultivating crops, burning forests, and changing the abundances of many types of plants. In some cases, these activities changed the landscape to the point that they are still evident in today's forests. These changes of the past may affect our understanding of modern ecology in one of the most biodiverse and culturally diverse places in the world.
2. Why is it important for society?
Amazonia holds approximately 15% of Earth's biodiversity and 17% of terrestrial carbon stocks. Because these forests are so vast and hold so much carbon, they are important components of global carbon models that predict how atmospheric CO2 levels will change in upcoming decades to centuries. These models current assume that Amazonian forests are in equilibrium and are not changing. However, past human activities and their legacies may result in forests that are still undergoing successional change, which could greatly affect carbon dynamics. The ALPHA project is looking to determine the successional stage of forests that are measured for biodiversity and carbon, so that researchers can understand whether or not these forests are in equilibrium or still undergoing successional change. This also makes the outcomes of the ALPHA project relevant for all of society.
The ALPHA project and its outcomes will also provide important data that can be used locally in Amazonia. Land rights of indigenous people are currently being questioned and threatened in many regions. Our data can show that indigenous people have lived on these lands for hundreds or thousands of years before Europeans came to the continent, and these types of data can be used in currently policy decisions regarding the land rights and ownership of indigenous people in certain areas.
3. What are the overall objectives?
The overall objectives of the ALPHA project are to generate data on the types, timing, duration, and locations of past human activities in Amazonian forests, and how/whether these activities leave signals that are still present in modern forests. We also aim to link these findings with current ecological and biogeographical patterns and processes documented in Amazonian forests over the last several decades. We aim to integrate past and modern ecology because what we observe and monitor today is usually dependent on processes that have occurred in the past, particularly in systems where individual trees live for hundreds of years - much longer than modern observations can see.
