Coupled Social and Natural Drivers of Deforestation and Ecosystem Change
at the Amazon Cropland Frontier
The Amazon forest faces an uncertain future and may be nearing a “tipping point” because deforestation, the spread of fire and a drying climate create a series of synergistic effects that lead to more clearing, forest degradation and “savannization,” or the replacement of moist rainforest vegetation with a more fire-prone savanna. Human decision-making at the deforestation frontier plays a critical role in these feedbacks by shaping Amazon land use and land management—which in turn dictates the nature and extent of environmental change and impacts at local and regional scales. In the last decade, forest clearing for cropland, primarily soybeans, has emerged as a major driver of deforestation across the southern Amazon (Nepstad et al. 2006). This introduces a new dynamic and set of influences into the array of causes of deforestation. This is because large farmers depend on access to financing in ways small farmers often do not and because large farms produce a product that is tightly tied to highly global commodity markets. The emergence of large crop farms in the Amazon also presents new opportunities for management of deforestation and associated environmental impacts precisely because of these links to larger market forces.
We propose to develop a multidisciplinary social science/natural science research group to investigate: (1) how this important new class of Amazon landowners and land managers makes decisions about land use and land management and (2) how those decisions are connected to key environmental responses such as decreased water quality, air pollution, soil erosion and greater risk of fire damage to remaining forests. We will focus on the southern Amazon agricultural frontier in the Brazilian state of Mato Grosso where a number of us have active (but not yet integrated) social science or natural science research programs. This activity will last one year. It will advance the integration of social and natural sciences at Brown by drawing researchers from five departments (Sociology, Economics, Geological Sciences, Ecology and Evolutionary Biology and the MBL’s Ecosystems Center). The targeted outcomes of our working group will be: (1) a research proposal to NSF Dynamics of Coupled Human and Natural Systems that will be submitted in November 2009, and (2) a short concept paper submitted to a broadly-focused scientific journal such as Frontiers in Ecology and Environment or BioScience that outlines evidence for linkages among social and natural systems at the cropland frontier.
Our working group will conduct the following activities:
- Hold a minimum of four targeted half-day discussion meetings that will: (1) identify key economic and social forces that drive decision-making by large farm owners and land managers, and (2) identify environmental responses that regulate feedbacks to future changes and influence forest and aquatic ecosystem function, human health and future agricultural productivity. Two discussions will be held on each of these questions. The discussions will be held jointly among working group participants across social and natural sciences. The outcomes of these discussions will be the identification of a concrete set of social drivers and environmental effects and agreements on how to best measure them.
- Use remote sensing to identify land use transitions and spatial arrangements of cropland and remnant forest in different portions of the Amazon agricultural frontier. We will use this information to identify regional landscapes and potential study areas that will allow us to compare different historical, social, ecological and regulatory characteristics. For example, we hypothesize that land cleared in the 1980s for pasture and then converted to soybean cropping in the 2000s will differ in several respects from land cleared from forest in the 2000s and put directly into cropland. We hypothesize that the forest-to-pasture soybean landscape will have more forest cleared to stream banks and more evidence of fires in the understory of standing forest and that the forest-to-soybean landscape will have greater riparian forest area, greater compliance with laws mandating uncut forest “legal reserves.”
- Develop a detailed conceptual model of the interactions between social drivers and ecosystem responses at the large farm frontier. This model will incorporate the important social and economic drivers and key ecological connections that emerge from the working discussions. The model will also be refined and adapted for the different social and ecological landscapes identified by the remote sensing activity. The model will provide a framework for incorporating and synthesizing existing information on social, economic and ecological interactions at the cropland frontier.
- Cultivate Brazilian collaborators across the social and natural sciences. Highly engaged in-country collaborators are essential for a project of this nature. Workshop participants have a number of strong existing relationships with Brazilian scientists but these currently fall along the lines of traditional disciplines. We will identify potential new collaborators and engage them in our discipline-crossing workshops with in-person and video conferencing.
- Write a proposal to NSF Dynamics of Coupled Human and Natural Systems for the November 19, 2009 deadline. Submit a synthesis article based on the core ideas of the proposal in November 2009.
This working group will be directed by Christopher Neill. It will consist of the following people, listed below with their main areas of interest as relevant to this activity. The group includes established faculty, new faculty and graduate students.
Christopher Neill, The Ecosystems Center, MBL and Department of Ecology and Evolutionary Biology. Watershed hydrology and biogeochemistry, riparian forest dynamics, stream biotic communities. Currently conducts research on effects of soybean expansion on soil biogeochemistry, watershed hydrology and water chemistry in Mato Grosso. Supervises Brown/MBL graduate student in Mato Grosso.
Leah VanWey, Department of Sociology. Household demography, migration, community economic development. Currently investigates links between migration and land use change at the soybean frontier in Mato Grosso.
John Mustard, Department of Geological Sciences. Remote sensing of land use change, temporal detection of land use change. Current research to identify land use transitions and agricultural practices at the Amazon agricultural frontier in Mato Grosso. Supervises Brown-MBL student in Mato Grosso.
Sriniketh Nagavarapu, Department of Economics. Impact of expanding ethanol production in Brazil on deforestation and regional inequality, interaction of environment, labor markets and health.
Meredith Hastings, Department of Geological Sciences. Atmospheric biogeochemistry, atmospheric transport. Interest in comparing air quality in the different agricultural environments in Mato Grasso and assessing the impact of nitrogen deposition on biogeochemistry locally and regionally.
Stephen Porder, Department of Ecology and Evolutionary Biology. Nutrient cycling across tropical landscapes. Co-supervises Brown-MBL student working in Mato Grosso.
Jerry Melillo, The Ecosystems Center, Marine Biological Laboratory and Department of Ecology and Evolutionary Biology. Regional and global ecosystem modeling. Currently developing ecosystem process models of agricultural lands at the Amazon cropland frontier in Mato Grosso.
Gillian Galford, Graduate student, Brown-MBL, Department of Geological Sciences. Current work on detection of land use change and identification of cropping practices in Mato Grosso.
Shelby Hayhoe, Graduate student, Brown-MBL, Department of Ecology and Evolutionary Biology. Current work on effects of forest conversion to soybeans on watershed level soil phosphorus and nitrogen cycling, hydrology and stream ecology.