Joost L. van Haren, Ph.D. - US grants

This CRPA project is about research on climate change impacts in the Amazonian rain forest and about motivating youth to consider science as a career objective. The project is an exhibit in Biosphere 2 in Arizona wherein a rain forest is maintained and will be used to augment the exhibit of large photos of scientists doing research. Particular attention will be paid to female scientists to motivate young girls. Biosphere 2 and the Girl Scout Council of Southern Arizona will collaborate to attract girls through free admission days to Biosphere 2.

These large photos will be equipped with sound and video so that as a visitor approaches the photo, the sounds of the forest as well as the researcher(s) will be heard. At this point the researcher, in the photograph, will begin a monologue with the visitor explaining what scientists are investigating and who the other workers are. In this monologue, the researcher will explain what they are doing specifically, why they are investigating this subject, and what they plan to derive as a scientific result. The exhibit will consist of fifty very large photographs (3x5 feet) with sound access via smart phones and headsets. In addition, there will be hands on equipment and docents for questions and discussion. The venue receives about 100,000 visitors per year consisting mainly of families, tourists, and clubs.

Through this exhibit, the researchers intend to motivate youth to develop interests in STEM topics. Girls are the main target audience. For families and tourists, the exhibit communicates the message of how science is being used to determine the effect of climate change on rain forests and how that would affect other aspects of weather and the global environment.

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Troch

This grant provides support for the acquisition of new environmental sensing and sampling capabilities to enhance and realize the scientific goals of the Landscape Evolution Observatory (LEO) at Biosphere 2 (B2) in Oracle, AZ. The goals of LEO are to permit controlled study of land surface fluxes of water, energy and carbon at the hillslope scale where key observables are monitored at sub-meter scales across a moderately complex landscape. The observed spatial and temporal variability of fluxes and their relationship and feedbacks to controlled and observed climatic parameters would then be used to inform improved models of land-surface water, energy and carbon cycling processes at larger watershed, continental and even global scales.

LEO consists of three replicated 340 m2 convergent experimental watershed mesocosms constructed inside a 5,000 m2 environmentally controlled facility at B2. The LEO mesocosms have as their basic design, three, 30 m length, 12 m width, 1 m depth, sloped (approximately 10 degrees from horizontal) steel tanks that have been filled with a grain size homogenized basaltic tephra as a starting soil. The tanks have as part of their frame design, arrays of distributed load cells that permit precise determination of weight changes across the tanks and located above the surface of the tanks are precipitation simulation systems that are rate controllable and can be varied across the surface of the soil tanks. An aspect of the design is that overland flow and erosion is specifically prevented by subsurface pumping and removal of water as the soil horizon saturates ? LEO is not designed for erosion process studies. The tanks are densely arrayed with sampling ports for drawing pore waters and gases and numerous sensor modalities have already been added including soil moisture content probes, soil temperature sensors, soil water potential sensors, soil water samplers, soil gas samplers, CO2 sensors, surface heat flux plates, electrical resistivity tomography probes, piezometers, and water flow and drainage flowmeters. The initial plan calls for 1-2 years of studies of the experimental landscapes devoid of vascular plants followed by the planting of an array of vascular plant types to allow for study of the co-evolution of the physical, chemical, and biological systems in the mesocosms and their influence on the land-atmosphere exchanges of water, energy and carbon.

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The Amazon basin contains nearly one million square kilometers of wetlands, predominantly peatlands, which are known to be highly productive and to store significant quantities of carbon in plant biomass and soil. Peatlands are characterized by soils rich in organic matter that are often saturated with water, and are therefore often low in oxygen. These conditions often lead to the release of methane, a greenhouse gas with ~25 times the heat-trapping capacity of carbon dioxide, and peatlands are known to be important global sources of methane. Until very recently, peatlands were not expected to be a significant component of the Amazon basin since these wetlands are more common in cold, northern latitudes and there were few records of their existence in the Amazon. In recent years, however, multiple studies aided by satellite imagery and guided field explorations have documented hundreds of peatlands across basins in the West and Central Amazon. An estimated 3-6 millions of tons of organic carbon are contained in these newly discovered Amazon peatlands, which may also represent a significant, previously unrecorded, source of methane annually. The magnitude of organic carbon stored in plants and soils every year vs. that released as methane from these peatlands is not known. This project proposes to evaluate for the first time a set of diverse Amazonian peatlands their organic carbon content, and rates of forest productivity and methane formation and release. This work will also include experimental manipulations of water levels to evaluate responses of productivity and methane release to environmental changes likely to occur as the climate warms. This project will also develop mathematical models of these ecosystems to evaluate the impact of peatlands at larger scales and to propose quantitative predictions for future productivity and methane emissions. Two hypotheses will be tested in this study including (i) whether vegetation change and water regime determine methane production and release, and (ii) whether the response of methane production to altered water regimes is modulated by the diversity of Amazon peatlands.

This work will contribute substantially to our understanding of feedbacks between changes in atmospheric chemistry and climate because of the magnitude of carbon storage in Amazonian peatlands and their potential to be major sources of methane. The research will provide the first comprehensive analysis of these peatlands in the Amazon, and provide quantitative predictions of future methane emissions from the Amazon. This project will also provide data on carbon stocks and fluxes for future comparisons under climatic change and will provide evidence to monitor tropical peatlands for future conservation and policy-making efforts. This collaborative effort including three US and one Peruvian institution, will train a postdoctoral researcher, two graduate and one undergraduate student. This project will also develop a virtual classroom program connecting high school students in Arizona and Iquitos Peru to discuss the impact of ecological research in Amazon peatlands and to track expeditions. Educational activities at the high school level will be targeted to generate an effective conservation-teaching tool to reach a broader public.

Tropical forests are the largest reservoirs of biodiversity on Earth and are under great threat due to deforestation. This project addresses the critically important question of how microbial biodiversity responds to and recovers from deforestation. Microorganisms are regarded as drivers of ecosystem processes and have not been characterized as extensively as plants and animals. The US-Brazil research team will focus on the potent green house gas methane and identify the producers and consumers along gradients of land use in the Amazon rainforest. The educational efforts for this project will build relationships between K-12 students in Brazil and US for biological conservation through live video conferences for training of undergraduate students and research mentoring of graduate students and postdoctoral associates. The microbial studies have important conservation and technological implications for forest management.

Direct and real time measurements of the methane gas in the soil-atmosphere interface will be combined with a targeted high throughput nucleic acid sequencing of microbes involved in the cycling of methane to assess their genetic, phylogenetic, and functional dimensions in two different regions of the Amazon rainforest. This work will result in the most extensive survey to date of the microbial diversity of any tropical ecosystem, the most comprehensive study of microbial responses to land use change ever documented, and the development of a novel approach for the integration of microbial biodiversity, allowing for accurate prediction of the effects of deforestation on the methane cycle.