Yale F&ES Doctoral Conference

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Science of Carbon

Gabriela Doria made her undergraduate studies in Biology at Universidad Nacional in Bogota, Colombia, her hometown. Since early on her career she has been actively involved in research on paleobotany and the use of fossil plants as indicators of climatic and ecological conditions of past environments. She fulfilled this first working at the Colombian Institute of Petroleum and as an intern at the Center of Tropical Paleoecology and Archaeology of the Smithsonian Research Institute (Panama City, Panama), and after as a graduate student at Wesleyan University (Middletown, Connecticut) where she obtained her Master’s degree in Earth and Environmental Sciences. Currently Gabriela is a first year doctoral student at the Yale School of Forestry and Environmental Studies under the supervision of Sir Peter Crane, Carl W. Knobloch, Jr. Dean of the School and Professor of Botany. Gabriela is passionate about plants and how these silent creatures have shaped life on Earth since remote times. She is also amazed with the current biological diversity of tropical terrestrial ecosystems, and that is why during her PhD studies she plans to explore issues in flowering plants evolution and the origin of Neotropical rainforests. During the next few years she will be investigating the plant fossil record of the Cretaceous (~145-65 Myrs ago) of northern South America (mainly Colombia), where she thinks she might find a valuable record of the coordination of ecosystem’s evolution and climate change in a much warmer world than today’s.

Title: Dead Plant Talking: Estimating atmospheric CO2 in the Middle Eocene (~40 Myrs ago) from stomata of the living fossil conifer Metasequoia 

Abstract: Plants are able to adapt to climatic and environmental changes, and for this reason fossil plants have been used as indicators of paleoclimatic and paleoenvironmental conditions, including the concentration of atmospheric CO2. One of the most prominent changes in Earth’s climate evolution was the transition from the extreme greenhouse world of the early Paleogene (~55 Myrs ago) to the present-day icehouse condition. However, there is substantial controversy over the history of climate and atmospheric CO2 during part of the Middle Eocene “doubthouse” interval (42-38 Myrs ago), including evidence for pulses of global warmth and ice sheet growth. Here I estimate the concentration of atmospheric CO2 during the late Middle Eocene (~40 Myrs ago) using stomatal indices of mummified Metasequoia needles from ten levels in an exceptionally preserved core from the Giraffe Pipe kimberlite in northwestern Canada (62°N paleolatitude). Reconstructed atmospheric CO2 values lie between 600-1000 ppm but with a secular decline to 400-500 ppm towards the top of the studied core. Because the CO2-threshold for nucleating large ice sheets during the Cenozoic is ~500 ppm, our CO2 record is most compatible with a transition from warm, largely ice-free conditions to cooler climates and the existence of ice sheets. Our fossils also unequivocally demonstrate that high-latitude deciduous forests thrived in the geologic past under atmospheric CO2 concentrations that will likely be reached within the current century (500-1000 ppm).


Xin Zhang is a third-year doctoral student at Yale School of Forestry & Environmental Studies (FES). Her research focuses on quantifying greenhouse gas budgets for ecosystems to formulate a firm scientific base for global change policy. She received her master’s degree from Peking University, where her thesis focused on “A footprint analysis of atmospheric pollution in the Pearl River Delta Region.” Before that, she graduated from Ocean University of China with bachelor degrees on Environmental Science and Computer Science. She served as a member of the Student Affairs Committee at FES, and currently is the President of the Association of Chinese Students and Scholars at Yale University.

Title: Characterizing CO2, CH4, and N2O Fluxes in a Landscape Dominated by Soybean and Corn

Abstract: In order to characterize the budgets of three major greenhouse gases (CO2, CH4 and N2O) from cropland, we conducted an experiment near Rosemount, Minnesota, in a landscape dominated by soybean and corn faming. The experiment was carried out at the plant, the ecosystem, and the regional scales. A steady-state flow-through chamber was used to measure the fluxes from the plants of soybean and corn. The gradient diffusion method was used to determine the fluxes at the ecosystem scale. Concentration measurements on a tall tower were used to drive a Lagrangian transport model to interoperate the surface fluxes at the regional scale. Measurements of CH4 and N2O at each scale were made using tunable diode laser spectroscopy.  The results to date are summarized as follows: 1) Corn plants were a small net sink of N2O with an average uptake of 4×10-4 µmol m-2 s-1 mainly occurring at night. The N2O flux of unfertilized soybean plants was below the instrument detection limit, and that of fertilized plants was a net source to the atmosphere at a rate of 5×10-3 µmol m-2 s-1 with the emission mainly occurring at night. 2) Both the corn and soybean plants showed a slight uptake of CH4 during the night and release during the day. The daily average CH4 flux was a small net sink for soybean (5×10-5 µmol m-2 s-1 ) and a small net source for corn (1×10-4 µmol m-2 s-1 ). 3) The soybean ecosystem was a source of N2O, with an emission rate of 1×10-4 µmol m-2 s-1 at night and 5×10-4 µmol m-2 s-1 during the day (The analysis of the ecosystem data for corn is under way). 4) The tall tower measurements indicate a strong source of CH4 and N2O at the regional scale. These results will be discussed in the context of a Lagrangian transport model, which is currently under development.


Yong Zhao is a second-year doctoral student at the Yale School of Forestry & Environmental Studies (FES), advised by Professor Peter Raymond. His research focuses on carbon transportation and cycling in a tidal salt marsh estuary. He received a Bachelor of Science degree in biology from the Yuanpei School of Peking University in 2006, advised by Professor Lu Zhi, founder and executive director of Conservation International-Shanshui Center of Nature and Society. He received a Master of Environmental Science degree at FES in 2008.

Title: High frequency monitoring of DIC, CDOM, PCO2, O2, and Chl_a Exchange between a Salt Marsh and Long Island Sound

Abstract: Recognized as one of the most productive ecosystems in the world, tidal salt marshes are sinks for oxygen and inorganic nutrients while sources of organic carbon. The areal extent of salt marshes is small in proportion of total global land-cover but they are still considered potentially significant as a source of dissolved organic carbon to the ocean. The marine-dominated estuary is differentiated from river-dominated estuaries by often receiving little freshwater besides direct precipitation and groundwater, and therefore, the material exchange between marine-dominated estuary and salt marsh is mainly driven by tidal cycle. Therefore, the material dynamics during the tidal cycle in marine-dominated estuary is essential to understand the function of salt marsh.  However, there is very limited information about the controls of material dynamics within and across marshes. The degree of marsh flooding and the period of a tidal cycle in daytime, for instance, might be an important component of regulating various of materials since the photosynthesis and particle deposition in salt marsh are indicated by them. In this research we consecutively monitor the concentration of CDOM, CO2, O2, Chlorophyll_a, as well as other necessary parameters in a tidal gate of a small salt marsh to address the pattern of carbon dynamic transportation in the water flux of tide. Here, we present our data collected in June 2009 in a salt marsh by Long Island Sound.


Ashley Keiser received a B.S. from the University of New Hampshire in environment science.  After spending three years as an environmental consultant. She is now a second-year Ph.D. student working with Mark Bradford. Her research interests lie in the field of terrestrial ecosystem ecology. Specifically, her dissertation focuses on forest dynamics and how global change is impacting nutrient feedback loops between microbial and plant communities.

Title:  One of these things is not like the other: Examining functional equivalence across soil microbial communities

Abstract: Soil microbial communities play a pivotal role in providing ecosystem services, given that they are key drivers of biogeochemical processes such as carbon and nitrogen cycling. As species-rich communities, made-up of populations with short generation times, it is commonly assumed that there is a high degree of functional redundancy within soil communities with respect to broad-physiological processes, such as organic carbon decomposition. This assumption underlies the majority of terrestrial ecosystem models, where relationships between processes and controlling factors are parameterized using statistical relationships generated from measurements across space.  However, microbial communities display biogeographic patterns, even at fine scales.  New work shows that these biogeographic patterns extend to microbial community function, with functioning influenced by differences in resource histories. We examined whether a common resource history might cause functionally dissimilar communities to converge functionally. Next, we tested whether functional convergence (partial or complete) is associated with a reduction in function in alternate environments (a functional ‘trade-off’).  We used a 6 x 2 (soil community inoculum x litter environment) full-factorial design under controlled, laboratory conditions.  Microcosm CO2 efflux was measured over three, successive 100-day periods, each representing a fresh inoculum step. Inocula were ‘back-crossed’ at the third step to explore trade-offs.


Society and Institutions

BinBin Jiang is a second-year doctoral student working with Marian Chertow.  She received a B.S. and M.S. in environmental engineering from Stanford University and worked for two years as an energy policy analyst before arriving at FES.  Her research focuses on studying the flow of energy and materials through the urban environment and the effect of these flows on communities. 

Title:  A history of urban metabolism - and a path forward

Abstract: This presentation is an examination of the intellectual history of urban metabolism.  Urban metabolism has been defined as “…the sum total of the technical and socioeconomic processes that occur in cities, resulting in growth, production of energy, and elimination of waste.” (Kennedy et. al., 2008)  The concept came into being in 1965 when Abel Wolman published an article that quantified the flows of energy, water, and materials of an imagined urban region.  The motivation behind measuring these flows is the analogy of the city as an organism, which has its roots in ecology.  The city can be likened to an ecosystem that hosts the production and consumption of organic matter (Odum, 1971).  Urban metabolism is often tied to the concepts of “industrial metabolism” (Ayres, 1994) and “social metabolism” (Fischer-Kowalski, 1998, 1999), which have their origins in the field of industrial ecology.  Because of its earliest roots in quantitative analysis, studying urban metabolism often means following the flow of energy, water, and materials through a well-defined, physical boundary or site.  Most of these studies have been conducted on a national, regional, or city-scale level, but a discussion of what the boundary or site actually means for the studies is usually not discussed or analyzed, but assumed.  The relationship between how humans respond to physical infrastructure of a city and the resulting consumption flows is also a topic that has not been addressed fully within the framework of urban metabolism.  This presentation will explore the potential of urban metabolism as a way to understand the history and people of a city in addition to its traditional role as an accounting method for physical flows.  I argue that thinking about the origins of the concept can help us to see broader applications of urban metabolism in understanding how to design healthy, sustainable communities.


Lauren Baker is a 2nd year doctoral student in the Yale School of Forestry and Environmental Studies focusing on international social justice and environment issues, especially surrounding indigenous rights and extractive industries. Her dissertation research will examine indigenous rights, values and identity politics in the Peruvian Amazon in the context of a recent and rapid expansion of oil exploration concessions.  She works with Michael Dove and Robert Bailis. Lauren also did a Masters of Environmental Management at F&ESy, graduating in 2005, and she worked for three years at the Center for International Environmental Law in Washington D.C., on the “Human Rights and Environment” and “Law and Communities” programs.

Title: Indigenous Tensions with Oil Exploration in the Peruvian Amazon

Abstract: In my presentation, I will highlight my findings from summer preliminary research about major tensions surrounding oil exploration concessions, which have recently and rapidly increased in the Peruvian Amazon and now cover around 75% of the Peruvian Amazon. Findings indicate that: 1) the legitimacy of the concessions was questioned at a fundamental level by many indigenous federation leaders, in a way that reinforced claims to indigenous sovereignty; 2) the concessioning process was often seen as being inadequate or illegitimate; 3) many indigenous peoples remained concerned about social and environmental impacts from oil, despite company and state assurances of new, clean and virtually impact-free oil exploration and exploitation; and 4) there were significant concerns about violence and repression. I will build upon this preliminary research for my doctoral research, which will further examine the ways in which indigenous rights and values are articulated in the Peruvian Amazon as a counterforce to State claims to subsoil and other natural resources, and to what ends.

Angel Hsu is a doctoral student at the Yale School of Forestry and Environmental Studies. Her research focuses on Chinese environmental performance measurement and data-driven approaches to policy. These approaches include remote sensing to monitor environmental change and statistical methods to evaluate data quality issues. Prior to coming to Yale, she was at the World Resources Institute (WRI), a non-profit environmental think tank in Washington, D.C., where she worked in the Climate Change and Energy program to develop voluntary greenhouse gas reporting initiatives in Mexico, Brazil, South Korea, India, and the Philippines.  She also managed the GHG Protocol’s programs in China. She has a Master of Philosophy degree in Environmental Policy from the University of Cambridge and a BS in Biology and BA in Political Science from Wake Forest University in Winston-Salem, North Carolina.

Title: Using remote sensing to inform environmental decision-making

Abstract: Regular collection of satellite imagery over the last 30 years provides a means of measuring environmental change and performance in China to inform decision-making processes.  This presentation will demonstrate two applications of remote sensing to improve environmental decision-making in China.  First, satellite data can be used to develop measures of environmental performance as indicators of how effective policies are in achieving environmental goals and targets.  This application will be demonstrated through an example of using remote sensing to derive forest cover metrics.  Second, satellite data can be used as a source of information by which to compare other types of environmental data.  The potential for this application will be shown through comparison of air quality information derived from remote sensing to ground-level measurements.  As the use of remote sensing is gaining wider adoption in international policy, this research will demonstrate the potential for remote sensing technologies to enhance environmental quality in a rapidly changing context such as China, serving as a model for other countries – both developed and developing – to strengthen environmental decision-making and policy formulation.


Catherine Picard is a fifth year doctoral candidate at the Yale School of Forestry & Environmental Studies working with Professors’ William Burch, Susan Clark. and Roderick Neumann. Her research interests include how to improve the practice of transboundary and large-scale conservation in Sub-Saharan Africa, with an emphasis on the policy process. Her dissertation is an appraisal of the design, implementation and impact of the Selous Niassa Wildlife Corridor, which is located on the Tanzanian-Mozambique border. Prior to Yale, she spent five years working for the John D. and Catherine T. MacArthur Foundation on a variety of international grant making programs, including biodiversity conservation, international peace and security, human rights and reproductive health. Her interest in the intersection of people, policy and protected areas was shaped her experiences growing up in Rwanda, Senegal, Swaziland, Namibia and South Africa. Ms. Picard has a B.S. from the University of California at Berkeley, and a M.S. from the University of Michigan, Ann Arbor.

Title: Conserving Tanzania’s Wildlife: What is the Policy Problem?

Abstract: More than one-third of Tanzania’s terrestrial land is officially protected, yet data confirm that wildlife populations continue to decline. Three types of problems (technical, governance and constitutive) are examined in detail to explain this trend. Technical problems occupy the bulk of people’s attention and resources and include poaching, habitat fragmentation, excessive bureaucracy, and economic inefficiencies. In contrast, governance problems are concerned with the decision-making process itself. This includes what problems are perceived, the types of data collected and disseminated, and how wildlife policies are debated, selected, implemented, appraised and terminated. Compounding weaknesses’ exist in each step of the decision making process. Finally, constitutive problems are grounded in the norms, beliefs, expectations and doctrine that implicitly shape how and who makes decisions about Tanzania’s wildlife. Constitutive problems are more opaque than technical or governance problems, but they precipitate and fuel many of the challenges facing Tanzania’s wildlife today. This presentation addresses current trends, underlying conditions and future projections for each problem type, and provide recommendations for upgrading the decision process as a whole. I conclude by suggesting that Tanzania’s wildlife cannot be effectively conserved until participants attend to all three – technical, governance and constitutive – types of problems.


Sara Smiley Smith graduated from Yale University’s joint masters program between the School of Epidemiology and Public Health and the School of Forestry and Environmental Studies in 2007 earning both an MPH and MESc. She is now pursuing a doctoral degree at FES, focusing on issues of sustainability and innovation diffusion.  During her time at Yale, she have also had the opportunity to work in the University’s Office of Sustainability. Her work as a research assistant in this office has centered around three main projects. She has worked to improve the move-out recycling and reuse efforts on the undergraduate campus known as Spring Salvage, increasing collection volume from 18 Tons in 2005 to 54 Tons in 2007.  Additionally, she had the opportunity to envision and implement an internally focused Yale Sustainability Summit.  This series of campus wide events was designed to share sustainability efforts taking place around campus, celebrate achievements, and stimulate conversations and new ideas about how to continue to improve Yale’s sustainability.  Finally, she has led two teams of graduate students in a pilot project seeking to understand how Yale’s Athletics Department and University Health Services can improve the sustainability of their operations.  This cooperative effort has helped to illuminate many of the operational opportunities and challenges to sustainability on an institutional campus which are informing my doctoral study.  Prior to arriving at Yale, she received my B.A. in Environmental Studies and Political Science from Middlebury College in Middlebury, VT in 2004. She spent her childhood on the remnants of her family’s dairy farm in the small town of Winslow, Maine. She is a 3rd year doctoral student. Her Committee Chair is John Wargo, also on her committee are Julie Newman and Garry Brewer.

Title: Harnessing Decision Making to Improve Institutional Sustainability:Examining Change in University Settings

Abstract:  In order to create a more sustainable modern civilization, we must enable innovative approaches to the myriad challenges we face from climate change to food provision. Institutions of higher learning have become leaders in evolving their internal structures, in some cases allowing for the rapid diffusion of innovations or innovative practices.  By better understanding the processes through which institutions harness innovation and incorporate new approaches to sustainability in their operations, we can share these lessons to enable other institutions to more rapidly innovate for sustainability. Understanding the barriers to and accelerators of change in these complex settings will enable more rapid diffusion of policies, management structures and technologies for sustainability throughout society.


Materials and Resources

Jason Rauch Now in his fourth year of study, Jason Rauch is wrapping up his research on global metal cycles.  Under the tutelage of Professor Thomas Graedel, Jason has quantified and mapped the combined technological and natural stocks and flows of the major metals utilized by human society. This research is a continuation of master’s work performed for a M.E.Sc. degree received in 2006 from FES. He became interested in the concepts and applications of industrial ecology after a facility visit exercise at a sawmill during FES Mods in 2004. Jason holds a Sc.B. degree in Geology-Biology and a B.A. degree in English Literature from Brown University, and plans on returning home to the wicked great State of Maine upon the completion of his studies at Yale.

Title: Spatial Indexing of the Human Impact on Al, Cu, Fe, and Zn Mass Mobilization

Abstract: With increasing consumption of material by human activity, the extent of influence relative to nature in the mobilization of metals and other elements on Earth continues to grow. Recognizing people as modern geomorphic agents, global data layers at 1° x 1° of human mediated mass flows (coal combustion, biomass burning, and mining) and nature mediate mass flows (net primary productivity, sea salt aerosol emission, and denudation to the oceans) are produced for the industrial metals of aluminium, iron, copper, and zinc for the year 2000. The major mobilization processes are denudation (natural) and mining (anthropic), though net primary productivity for Zn and Cu and coal combustion for Al are nearly as significant. All flows are subsequently combined into an index representing human versus nature flow dominance. As the first maps of mobilization flows of metals widely used by modern technology, they reveal that ~1-5% (depending upon the metal) of Earth’s land surface now has metal flow dominated by human activity.


Keita Ebisu is a third year PhD student at School of Forestry and Environmental Studies at Yale University. He is focusing on epidemiology and environmental statistics, particularly air pollution effect on human health. He finished his master’s degree in Biostatistics at Yale, and worked Yale School of Medicine as a programmer analyst for three years. Currently, he is involved in PM chemical component effect on birth weight with his adviser, Dr. Michelle Bell.

Title: Developed Land-use in Connecticut

Abstract:  Children’s respiratory health has been linked to many factors, including air pollution. The relationship between developed land-use and health is not fully understood, although this is of key importance given the growing populations living in urban environments. We investigated whether the degree of developed land-use near a family’s residence is associated with risk of infants’ respiratory symptoms. Wheeze occurrence was recorded for the first year of life for 680 infants in Connecticut for 1996-1998. Land-use categories were generated using satellite imagery. The fraction of developed land-use near the subject’s home was related to risk of wheeze symptoms using logistic regression. NO2 exposure, as a proxy for traffic pollutants, was estimated using integrated exposure traffic modeling. Effect modification between developed land-use and income was explored. An interquartile increase in developed land-use within 810m of infant’s residence was associated with 1.61 times higher risk of wheeze (95% confidence interval, 1.12-2.33). When both NO2 and developed land-use are included in a single model, neither is statistically significant. Developed land-use had a higher association with wheeze for infants from lower income families. Our analysis indicates that developed land-use is associated with infants’ risk of wheeze symptoms, and that this effect differs by socio-economic status. Findings indicate that health effect estimates for development incorporate some effect of traffic-related emissions, but also involve other urban factors. These may include different structure of developed land-use, housing characteristics, or baseline health care status.


Jooyoung Park Before coming to Yale, I studied at Seoul National University in Korea and earned both BA and MA degrees in environmental engineering.  I especially committed to develop a bio-remediation technology, which enhances degradation potentials of natural subsurface environment.  I also worked on hydrogen and biomass energy policy assessment at Korean Energy Economics Institute.  Based on my experience on technology and policy, I have been searching for a way how to integrate technology and policy in a way to restructure and redesign our system more sustainable.  Industrial ecology is the one I found as an effective approach towards such a goal.  It provides fertile ground to experiment various efforts towards sustainability in a systemic way.  Now my interests range over waste management, inter-firm cooperation, system-level sustainability, and complex systems theory.

Title:  Wastes as resources: the management of and cooperation for coal combustion by-                     products utilization

Abstract: Inspired and motivated by industrial symbiosis, this research attempts to explore technical and managerial aspects of industrial waste reuse, in case of coal combustion by-products (CCBs).  CCBs can be viewed as wastes since they are unintentionally generated during power generation and need to be discarded from a coal power plant’s perspective.  However, they are also resources as they’re currently reused in various applications such as construction and agricultural purposes.  In order to reflect the values of CCBs, this study will find an innovative way to define and characterize wastes by comparing fly ash, bottom ash, and FGD gypsum.  Then, how different features of CCBs influence the behaviors of industries will be investigated.  Industrial waste reuse requires cooperation among waste generators and users, but our understanding about relational dynamics is still lacking, which hinders further expansion of waste reuse practices.  To describe transaction behaviors for CCBs utilization, I will draw economic and social factors from inter-organizational relationship literature.  Also, the current status of CCB utilization and its economic and environmental implications will be analyzed at a national level.


Luisa Cortesa, Ph.D. Anthropology and F&ES, first year, interested in social development processes and their intersection with decentralized and sustainable water management. Researching in India since 2003, I worked in the flood vulnerable Gangetic plains as an applied anthropologist for a network of small local NGOs during the occurrence of two major floods (2007-8). My research interests are on the fence of anthropology and environmental sciences: the geography of recurrent disasters and its material and cultural adaptability, contradictory ideas of sustainable and equitable development in a complex political landscape, the relation between technologies of water management and power/knowledge dynamics. My overall goal is an applied project that brings academic anthropological knowledge into the practice of social development and water management interventions. Main advisors: M.Dove, K.Shivaramakrishnan

Title: Making sense of floods

Abstract: What does it mean to drink water in floods? I propose to answer this
question by studying the way in which floods are experienced and shape
life and geography in the complex environmental and political landscape
of rural North Bihar, East India. From the perception of water in a
recurrent disaster, I intend to study how water abundance and water
scarcity are enmeshed with dynamics of knowledge and power, through the
lens of water management interventions and technologies for accessing
drinking water.



Human-Ecological Systems

Mary Rogalski A growing body of research provides evidence of contemporary evolution: the potential for species to show evolutionary responses to environmental changes in timescales relevant to ecological processes.  Anthropogenic environmental change has been shown to drive some of the most rapid rates of evolution.  I am broadly interested in this intersection between ecology, evolution and human modification of landscapes.  Beyond contributing to the ‘proof of concept’ aspect of contemporary evolution, I hope to add to our understanding of the relative importance of ecological vs. evolutionary dynamics in population and community level responses to environmental changes.  I am also interested in ways that evolutionary responses can enhance or impede ecological responses and vice versa.  I have an undergraduate degree in biology and environmental science form the College of William and Mary and a MESc degree from Yale F&ES.  After earning my bachelor’s degree I spent three years learning about environmental science policy and federal R&D appropriations in DC, followed by two years as a park naturalist, mostly dedicating my time to environmental education and park restoration activities.  My interests in geography, environmental history, ecology and evolution have been shaped by these experiences.

Title: Contributing to the next generation of biological indicators

Abstract: The intensifying pressures of urbanization and development place ever increasing demands on our ecosystems.  As a result, watersheds absorb a complex mixture of heavy metals, pesticides, fertilizers, pharmaceuticals and food additives with unknown consequences to ecological health.  Biological indicators ? organisms that are relatively sensitive or resilient to anthropogenic influences ? can help in understanding the environmental stress experienced in a habitat, integrating the impacts of weeks to months or years of exposure on the ecosystem.  While the toxic effects of many contaminants have been tested on organisms in controlled laboratory experiments, the impacts of mixtures of chemicals in an ecosystem context are largely unpredictable.  Even less is known about long term impacts of human activities on ecological communities. In my doctoral research I will use freshwater zooplankton communities to contribute to the next generation of biological indicators.  I aim to test whether EPA toxicity tests conducted on zooplankton predict sensitivity to pollutants found in the environment.  I will use sediment profiles and zooplankton resting eggs found in lake sediments to document the history of pollution impacts on zooplankton communities over the past several decades. Additionally, my work will expand our understanding of how landscape context affects how communities respond to and recover from anthropogenic stress.


Adrian Cerezo For twenty years Adrián Cerezo has explored human development from multiple perspectives as student, researcher, teacher, trainer, evaluator of programs, curriculum designer, education materials developer, writer of children’s books, participant in international forums, developer and designer of out-if-school programs, museum design consultant; and education program manager. His work is guided by one question: Can humans learn to live more sustainably? For the last five years, his research as M.E.Sc. and Ph.D. student at Yale’s School of Forestry and Environmental Studies has focused on the fundamental importance of early child care and development in the process of human development, particularly, the complex interrelations between the quality of early childhood and the environment (a network composed by individual, primary caregivers, community and ecosystem) in which children develop. Adrián holds a B.A. in Psychology and a M.E.Sc. in Social Ecology. He has been an Education Fellow at the Conservation Research Center of the Smithsonian Institution; has consulted for governments as well as multiple environmental and educational organizations; is a member of the Communication and Education Committee of the International Union for the Conservation of Nature; serves on the board of A World for my Baby (a non-profit focused on early child care and development in San Juan, Puerto Rico); is a member of Yale’s Edward Zigler Center in Child Development and Social Policy - Knowledge Center for the South-East Asia Region; provides technical advice on early child care and development to the Children and Nature Network; and in December of 2009 led the delegation of the Consultative Group on Early Child Care and Development at the United Nations Framework Conference on Climate Change (Copenhagen, Denmark).

Title: What Doesn’t Kill You: The Dynamic Role of the Ecologic System in Early Childhood                   Development Quality

Abstract: In the last century infant mortality rates have decreased from 300 (avg.) in every thousand babies born, to a current global average of 71/1000. According to the most recent World Health Organization statistics, only 10 countries have more that 10% mortality, while over 68 countries have mortality rates below 1%. In the case of the United States, the current mortality rate is .77%.

Humans have made great strides in understanding and addressing the factors responsible for infant mortality: infectious disease (in both mother and child), malnutrition, improper peri-natal care, prematurity and low birth weight, environmental toxicity, and congenital abnormalities (WHO, 2009). Around the world the rate of infant mortality is in a continuing downward trend as more communities gain improved sanitation, access to medical care, access to antiseptic water and increased nutrition. While the idea that about 15,000 children die every day around the world (mostly from preventable problems), this number is much lower than the 87,000 children that would die every day if we apply 19th century mortality rates to our present population.

In building a world that doesn’t kill our babies, we have significantly reshaped the geophysical, ecologic, chemical and atmospheric landscape. We have also reconfigured our social relations and individual characteristics. As we become more aware of the significant negative implications these changes have on the biosphere and the social sphere. The question arises: is it really true that what doesn’t kill you, makes you stronger?

My project will consider three general questions: 1)beyond survival, what is the role of the ecologic system in supporting early childhood development?; 2)what is the cost of modern environmental modifications on early childhood development?; 3)is there a relation between sustainability of a community and the quality of ECD?

More specifically, I will be considering if communities designed to promote extreme individual environmental footprints also have a decreased quality of early childhood development.

My presentation will describe the theoretic framework used conceptualize the early childhood development network of a community and the methods I will be using to document and analyze the phenomena under study.



Steven Brady I am in my third year of study in the Doctoral Program following two years at FES in the M.E.Sc. Program.  Professor David Skelly is my primary advisor.  My interest in science dates back to the days when Mr. Wizard wowed young TV audiences with such timeless tricks as freezing his finger in liquid nitrogen and smashing it to pieces with a hammer.  Fortunately, Mr. Wizard—being a, well, wiz—had the foresight to know this would happen and substituted a hot dog for his finger.  Phew - I was hooked!  More recently, my interest in environmental science was shaped by my experience as a Peace Corps Volunteer in Kenya, where I worked on sustainable agriculture extension.  At present, I am enamored by wetlands, and the amphibians that dwell there.  Developing understanding of the long-term responses of amphibians to the dynamic human enterprise—especially in relation to roads and runoff—motivates my research.

Title: The influence of roads on wetland amphibians

Abstract: The network of roads on the landscape is vast: approximately 80% of all land in the conterminous U.S. is located within one km of a road. This formidable road presence contributes a suite of environmental impacts, including road-kill, fragmentation, and runoff. When wetlands intersect the path of such runoff, substantial concentrations of contaminants can accumulate in aquatic habitat. This is especially pronounced in small and shallow wetlands, such as ephemeral pools, which host a suite of amphibian species found nowhere else. Among contaminants found in runoff, which include heavy metals, petrochemicals, and deicers, road salt has garnered much recent attention because of its widespread application as the predominant road-deicing agent. Yet despite a growing interest aimed at understanding ecological impacts of roads and runoff, our knowledge of long-term consequences of roads on the environment remains nascent. This stems in part from a dearth of investigations, and in part because such investigations ignore evolution on contemporary timescales, focusing instead on traditional ecological inference. Yet reports of evolution influencing ecological outcomes are growing, suggesting this influence may be the rule, not the exception. This implies that our insights into road effects are limited to immediate outcomes, naïve to long-term responses associated with local evolutionary change. Such shortsighted understanding may be especially relevant for species characterized by spatially structured populations, such as amphibians. This suggests that amphibians dwelling in roadside wetlands may evolve rapidly in response to runoff, thus becoming differentiated from local populations removed from the influence of roads. Full understanding of road impacts on wetland amphibians requires a spatial approach aimed to evaluate responses on a local population level. 

I evaluated this potential population specific response to roads and runoff for each of two wetland amphibian species: the wood frog and the spotted salamander. I employed a three-pronged approach comprised of reciprocal transplant field experiments, laboratory salt exposure manipulations, and field observations of wild populations. In each of these approaches, I measured amphibian growth, development, and survival to assess the performance impact of roadside environments, and whether this impact varies with respect to population origin.  Specifically, I evaluated the response of individuals originating from two types of wetlands: those located < 10 m from a road (roadside wetlands) and those located > 200 m from a road (woodland wetlands).  Overall, I found that road salt and road adjacency negatively influenced wood frog and spotted salamander growth, development, and survival. (Because results between these two species were qualitatively similar, and for the sake of concision, I report here key results concerning only the wood frog, but will discuss both species in my presentation.) Following chronic exposure to ecologically relevant levels of road salt, pre-metamorphic wood frog larvae were 13 % lighter in mass than larvae reared in a standard water solution. Further, the negative influence of road salt and road adjacency varied with respect to wetland origin type. Strikingly, wood frogs from roadside wetlands survived less than those from woodland wetlands. In a filed-based reciprocal transplant experiment, embryonic wood frogs originating from roadside wetlands survived on average 20% less than their woodland counterparts. Similarly, following acute exposure to road salt, roadside larval wood frogs survived 24% less than those larvae originating from woodland wetlands. These results suggest first that roadside wetlands are harsh environments for embryonic and larval amphibians, and second, that the ability to cope with roads differs by population origin with respect to road proximity. The subset of the population of wood frogs and spotted salamanders most susceptible to the influence of roadside environments may be that which is least capable of persisting there. These results pose questions about the mechanisms generating this divergent response, and indicate that roadside wetlands may induce sink dynamics coupled with inherited negative environmental effects.



Alvaro Redondo-Brenes is originally from Cartago, Costa Rica. He holds a BSc. in Forestry Engineering from the Technological Institute of Costa Rica and a MFS from the Yale School of Forestry and Environmental Studies. Prior to attending Yale F&ES he worked at La Selva Biological Station (Organization for Tropical Studies). At present, he is a doctoral candidate in the Program of Tropical Forestry at F&ES. He is assessing the effects of land use, political, and socio-economic factors on the conservation of bird and mammal species in the Path of the Tapir Biological Corridor and in the Osa Peninsula region, Southwestern, Costa Rica.

Title: Effects of Land-Use Change on the Conservation of Bird Species in the Path of the Tapir Biological Corridor

Abstract: I studied bird species diversity in ten different land-use types in the Path of the Tapir Biological Corridor, Costa Rica from 2007-2009. The ten land-use types were wildlife refuges, biological reserves, tree plantations, forest fallows, forest edges, villages, residential tourism projects, homegardens, agrosilvopastoral systems, and oil palm plantations. I was interested in determining how important the ten different habitat types are for maintaining the bird diversity of the corridor and how these land uses can be managed to enhance their conservation value. To address these questions I selected 20 different sampling points for each habitat type. Bird surveys were carried out over a two-year period. Each point was surveyed three times over the summer and three times over the winter periods of each year, total 12 visits per point. Total observation time was 400 hours. Aside from bird identification, I also recorded bird activities (e.g. foraging, nesting) and microhabitat were they registered (e.g. tree, shrub, ground). 

 I found a total of 44,917 birds from 48 families, and 334 species. Eighty one percent of birds were recorded utilizing forested habitats. However, also 77% of registered birds were found in the human-modified land-use types.  Moreover, 44.5% of species were classified as forest specialist, 38.9% forest generalist, and 16.6% open area specialist. Regarding feeding guilds, 53.8% of species were classified as insectivores, 21.2% frugivores, 9% nectarivores, and carnivores and granivores 8% each. I also identified a total of 32 threatened species and 22 endemic species. Eight of the 22 endemic species were also under threat, and three endangered species were registered: Ara macao, Amazilia boucardi, and Icterus mesomelas. Overall, 64% and 75% of endemic and threatened species, respectively, were forest-dependent species. Based on concepts of sustainable forestry, forest-dependency of most species, and socio-political and economic situation in the PTBC, it was suggested that the corridor would be sustainable if the natural resources are managed in a gradation including protected areas, integrated management areas, and tree plantations. Payment for environmental services, ecotourism, reforestation, environmental education programs, and private investment, among others, will provide the incentives and infrastructure that local people need to practice integrated management effectively. 

Elaine Hooper is a 4th year doctoral candidate at Yale School of Forestry and Environmental Studies. For her doctoral dissertation, Elaine conducted over 2 years of fieldwork in the Brazilian Amazon, where she studied the effects of forest fragmentation on forest regeneration. Her major faculty advisor is Mark Ashton (Professor - Yale School of Forestry and Environmental Studies), and her research is co-chaired by Douglas Daly (Director of Amazonian Botany – New York Botanical Gardens). David Skelly (Professor – Yale School of Forestry and Environmental Studies) and Pierre Legendre (Professor – Universite de Montreal) are also advisors for this project. This research is a continuation of Elaine’s interest in the factors affecting the regeneration of native tropical tree species in anthropogenically-modified landscapes which began with her Master’s degree research, where she studied the factors affecting forest regeneration in deforested areas in Panama invaded by the exotic grass Saccharum spontaneum.

Title: Effect of forest fragmentation on forest regeneration in the Brazilian Amazon

Abstract: Fragmentation of tropical forests is a major cause of global biodiversity loss, however the effects of forest fragmentation on the biodiversity and species composition of neotropical forest regeneration are poorly understood. I hypothesized that forest fragmentation negatively affects the diversity of regenerating neotropical forests and alters species composition of tree and shrub regeneration and tested these hypotheses at the Biological Dynamics of Forest Fragments Project site, located in the Brazilian Amazon. In 120, 10 m2 experimental plots I compared tree and shrub seedling species richness and composition in continuous forest controls to forest fragments of different sizes (1, 10, and 100 ha) and also at different distances from forest fragment edges to determine whether area and edge effects respectively affect forest regeneration dynamics. To determine the importance of various factors hypothesized to affect the species diversity and community composition of forest regeneration, I measured abiotic (light, soil moisture, temperature, humidity, and edaphic factors) and biotic (seed rain, seed predation, and herbivory) factors at each of the experimental plots. In this presentation, I discuss the relative contribution of these abiotic and biotic factors in driving biodiversity losses and species compositional changes in forest fragments.