Linking Ecological Biology and Geoscience

Report to the National Science Foundation
April 4, 2002

Workshop held at the annual meeting of the
Ecological Society of America
August 4-5, 2001
Madison, Wisconsin

Organizing committee:
Lars Hedin¹ (chair),
Oliver Chadwick², Josh Schimel², and Margaret Torn³

1Princeton University, Princeton, NJ
²University of California, Santa Barbara, CA
³Lawrence Berkeley National Lab, Berkeley, CA

Executive summary:

Basic environmental science will increasingly depend on collaborations between biologists and geoscientists. This report summarizes a meeting of 30 leading scientists and managers of science, charged with examining how to enhance and sustain research across the interface of ecological biology and geological science in land-based ecosystems.

Despite urgent need for convergence across the fields of biology and geoscience, progress has been severely limited by institutional, programmatic, and social barriers. The committee identified the urgent need to establish an intellectual home for the emerging field of "biogeosciences," within funding agencies, educational institutions, and professional societies. The interdisciplinary nature of biogeosciences makes it particularly difficult to fit within traditional administrative structures. For example, NSF and other funding agencies lack programs for sustained support of basic research at this important interface. While universities have been similarly challenged, a few leading institutions have responded by establishing new interdisciplinary programs outside the traditional disciplinary boundaries of departments. Professional societies are also struggling with how to engage biogeosciences, despite the limitations inherent in their disciplinary structure.

The committee identified as most important the problem of ensuring long-term and predictable funding for fundamental research across the interface of biology and geoscience. The current organization of NSF funding panels presents a difficult obstacle to collaborations between biologists and geoscientists, with only limited (and unpredictable) opportunities for high-quality panel evaluation and sustained funding. To develop visionary leadership in this important area, NSF must establish a permanent program in "biogeosciences." To be most effective, such a program should include participation from biologists and geoscientists, and should be closely aligned with global carbon and climate change programs. There is furthermore an urgent need for the NSF and other funding agencies to develop an explicit mechanism to evaluate collaborative interdisciplinary proposals. Additional synergism could be derived from interactions with other federal agencies that benefit from enhanced scientific readiness in this area (e.g. USDA, NASA, USGS, etc.), either through development of joint initiatives or platforms, or through advertising of capabilities, opportunities, and needs (e.g., databases, infrastructure, etc.) within particular agencies.

A lack of joint (i.e., linking biologists and geoscientists) programmatic platforms and initiatives to address fundamental questions is a further barrier to progress within the vibrant intellectual core areas of biogeosciences. The committee recommended the development of such initiatives including experimental campaigns, field sites, and the operation of specialized laboratories and training programs. There is particular value in joint experimental field sites – or "natural laboratories" -- as long as these are carefully selected to answer specific questions, or to leverage new measures within well-characterized sites with appropriate infrastructure. The committee outlined three core areas of particular importance: (i) the "co-development of biota, soils, and nutrient cycles across diverse terrestrial ecosystems"; (ii) the "integration of processes across broad spatial and/or temporal scales," and (iii) the "role of human activities and social trends as drivers of environmental change."

Most broadly, progress depends on maintaining quality interactions between biologists and geoscientists. A number of mechanisms can promote this, including joint graduate training programs, the establishment of a new biogeosciences section in the Ecological Society of America (which would interact with the recently developed section within the American Geophysical Union), and joint meetings in Chapman- or Gordon-type conferences. Additional workshops are needed to further develop a common vision, specific platform-level initiatives, and to examine how the field of biogeosciences interfaces synergistically with other major environmental programs.

The disciplinary basis of environmental science is in the process of re-formulation. It is increasingly clear that answers to many of the most vexing questions about how humans impact our natural environment depend on processes and phenomena that span biological and physical sciences. Biotic diversity and complexity depend intimately on processes in the physicochemical environment. Conversely, fundamental physicochemical phenomena such as weathering, climate, and the development of soil fertility rely closely on biological processes. This means that complex problems such as climate change, acid rain, eutrophication, and biodiversity loss are inherently interdisciplinary – that is, shaped by multiple feedbacks between biological and physicochemical processes. Our understanding of basic environmental science has therefore arrived at a new intellectual frontier: a natural convergence of the historically distinct disciplines of biology and physical science.

This disciplinary convergence will over the next several decades transform our understanding of basic processes that control the stability and sustainability of natural environmental systems. The ensuing findings will have extraordinary implications for our abilities to predict and manage how humans impact the health of ecosystems across local, regional, and global scales. Such knowledge is a critical component of a safe, sustainable, and prosperous future.

Managers and practitioners of science increasingly understand the intellectual potential of this interdisciplinary marriage. This can be seen in several recent assessments of environmental science^1,,, the emergence of conceptual themes such as "geobiology" and the "critical zone" within the geosciences³, and the growing focus on ecosystems, biogeochemistry, and "biophysics" within environmental biology¹.

Links between biology and geoscience are not new; historical examples include seminal ideas by Svante Arrhenius on carbon dioxide and global climate, Vladimir Vernadsky on global biogeochemical cycles, and Alfred Redfield on the co-development of organisms and nutrients in the world’s oceans. What is new, however, is that both biology and geoscience have now developed to a point where convergence is broadly available, and where the potential for interdisciplinary synergism is unprecedented and critical for resolving key environmental problems. Recent progress of concepts, methods (e.g., genomics, molecular biology, and isotopes), observational tools (e.g., satellites), databases (e.g., soils, vegetation, and land-use change), and computational abilities have virtually revolutionized scientific readiness and opportunities at this interface.

Despite these opportunities, however, there exist barriers to developing and sustaining integrated research and training across the biology-geoscience interface. We convened a group of 30 scientists and managers of science (appendix 1) to discuss opportunities for, and obstacles to, developing sustained, broadly inclusive, and effective research collaborations among ecological biologists and geoscientists. This committee addressed the emerging field of "biogeosciences," identified barriers to further growth, and examined opportunities for developing platform-level initiatives to address intellectually broad questions that are central to understanding the earth system.

The term "biogeosciences" refers broadly to research that links biological, geophysical, and geochemical approaches to understand the earth system. These approaches include biogeochemistry (fluxes of matter and energy), biophysics (interactions of climatic, physical, and physiological processes), and ecosystem geomorphology and hydrology (interactions of biota, landforms, and water). Biogeosciences is a new discipline, based on technologies and concepts that enable the study of earth-system processes and mechanisms across a continuum of spatial and temporal scales – from microbes to global environments, and from physiological responses to the geologic record. Just as the development of molecular techniques has powered an explosion of basic biological knowledge, the development of new satellite sensors, computer models, and global informatics resources are fueling a parallel explosion for understanding how earth system processes scale from local to global. Building on basic knowledge about underlying mechanisms, biogeosciences thus examines basic aspects of the function of the earth system.

Committee recommendation: That "biogeosciences" is recognized as an emerging discipline central to the overall intellectual goal of understanding the function of the earth system.

While the unique and vitally important contribution of biogeosciences is increasingly recognized, significant barriers remain to developing effective links between the fields of biology, geophysics, and geochemistry. The interdisciplinary nature of biogeosciences makes it difficult to fit within traditional administrative structures. The committee identified as most critical to further progress the question of how to develop a sustained interdisciplinary home for biogeosciences, despite the traditional disciplinary structure of funding, educational, and professional institutions?

1. National Science Foundation: The National Science Foundation (NSF) and other funding agencies (discussed in point 4, below) entirely lack programs for the sustained support of basic research across the biology-geoscience interface. The current organization of programs and panels at the NSF presents a major obstacle to intellectual progress. Opportunities for funding unique, innovative, and interdisciplinary work are limited and unpredictable, typically appearing as periodic three to five-year thematic programs with little or no sustained vision. While there is much rhetoric about the importance of collaborations across disciplines, traditional funding panels appear ill equipped to adequately review interdisciplinary projects, and are sometimes reluctant to defer scarce research dollars from more traditional disciplinary targets. In fact, many questions that are central to the field of biogeosciences fall largely outside the traditional disciplinary programs of biology, geosciences, and hydrology. While there have been a few examples of successful large-scale interdisciplinary programs (e.g., "Coupled Biogeochemical Cycles" within NSF, or "Boreal Ecosystem-Atmosphere Study" co-sponsored by NASA, NOAA, NSF, EPA and other agencies), these have been of limited duration and have therefore not been able to offer sustained and evolutionary leadership.

The committee identified fragmentation of leadership and resources across administrative boundaries within the NSF as the central argument for why the current "piecemeal" model of funding across different programs can not sustain the interdisciplinary creativity needed to foster excellence and visionary leadership across the biology-geoscience interface.

Committee recommendation: To ensure visionary, evolving, and sustained leadership in interdisciplinary environmental science, it is imperative that the NSF and other funding agencies develop permanent programmatic "homes" for the support of biogeosciences. To be most effective, such programs should be jointly sponsored by, and include representation from, both the ecological and geoscience community. While such a "home" ought to function independently of traditional disciplinary NSF programs, it should encourage and support biogeochemical perspectives across the full range of NSF programs, including the biosciences, geosciences, hydrology, and oceanography. The program should also be closely aligned with other targeted environmental initiatives, in particular those in carbon cycling, climate change, and biocomplexity. In addition to establishing such a "home" for biogeosciences, there is an urgent need for the NSF (and other funding agencies) to develop clear mechanisms that ensure that interdisciplinary proposals receive appropriate evaluation, even when they are submitted to traditional disciplinary programs.

2. Universities: Similar to funding agencies, universities are seriously challenged by the ongoing re-formulation of environmental science. For many institutions, the critical question is how to foster strong and visionary collaborations across disciplines and departments, with minimal need for administrative structure and boundaries? Responses have largely followed two different paths: the formation of centers or institutes that facilitate interdisciplinary interactions across traditional departments, or the formation of entirely new departments that house interdisciplinary collections of environmental faculty.

New opportunities in research, and in developing novel student training programs and technological infrastructure accompany the growth of biogeosciences within universities. Several recent critical reviews^2,3. of U.S. environmental science have called for the establishment of such interdisciplinary training programs and infrastructure. The emergence of biogeosciences offers an important opportunity for building such capacity.

Committee recommendation: The growth of biogeosciences within universities offers a unique opportunity to integrate research, training, and experimental facilities in an interdisciplinary context. The NSF should take advantage of this opportunity for leadership by instituting training (at doctoral and post-doctoral levels) and equipment grants in the biogeosciences.

3. Professional societies: The disciplinary nature of scientific societies limits their ability to respond to the emergence of the field of biogeosciences. The American Geophysical Union (AGU) has shown visionary leadership, however, by recently instituting a new "biogeosciences" section that attracts both geoscientists and ecologists in an intellectually open format. To ensure that the field of biogeosciences grows in an intellectually broad and balanced manner, it is critical that also other societies follow AGU’s leadership and develop similar programs. Of central importance are the Ecological Society of America (ESA), which offer an essential link to biological processes, and the Soil Science Society of America (SSSA), which emphasizes soil-based processes.

Interactions among professional societies are critical for ensuring that the field of biogeosciences grows in an inclusive and balanced manner. Such interactions can take the form of jointly sponsored symposia at annual meetings, or jointly sponsored workshops. Foundations such as the NSF can play important roles by promoting such interactions.

Committee recommendation: There is an urgent need to promote biogeosciences sections within leading societies in ecology and geosciences, and interactions among these sections to coordinate intellectual exchange across disciplines. Funding from the NSF and other societies would have an important impact on the establishment of such sections, and for promoting exchange across them.

4. Other federal agencies: Environmental programs in agencies such as USGS, USDA, DOE, NASA, and the US Forest Service stand to benefit from enhanced scientific maturity and readiness in biogeosciences. In addition, these agencies have developed knowledge, tools (e.g., satellite imagery, carbon dioxide fertilization experiments, etc.) and databases (e.g., geographical-based databases, forest census plots, etc.) that are critical for advances within the biogeosciences. Important synergisms may be derived from interactions between these federal agencies and the NSF, based on joint large-scale initiatives or platforms (see below). Opportunities for such joint ventures could be identified through advertising of capabilities, opportunities, and needs within different agencies. Such advertising would be particularly beneficial in the case of land management agencies, for which scientific needs may provide guidance for new activities, and existing databases may provide important information for basic scientific efforts.

Committee recommendation: The NSF and other federal agencies should strongly consider establishing an interagency working group to coordinate synergisms and opportunities within the field of biogeosciences. Interactions across agencies could be further promoted by targeting funds for federal scientists interested in collaborating in NSF-funded interdisciplinary projects, or for non-federal scientists interested in collaborating with federal agencies.

Biogeosciences addresses a broad range of basic questions. Some of these concern fluxes of matter and energy, for example, how are human actions changing natural distributions and cycles of nutrients and elements? Such questions are critical not only for elements like carbon, which cycles in vast quantities and plays a critical role in climate, but also for elements like cadmium, which has important implications for human health. Other questions concern the coupling of earth system function across temporal and spatial scales. These and similar questions probe deeply into the structure and function of the natural and the human-managed world. While the questions have been posed in different guises for decades, we are just now entering the stage when the available tools are powerful enough to provide definitive answers.

The committee identified three core intellectual areas that presently are of particular importance to progress on both basic and applied issues:

1. "Co-development of biota, soils, atmosphere, and climate." This area focuses on how to improve our understanding of the tremendous structural and functional diversity that characterizes land-based ecosystems. How do functional differences across ecosystems emerge from the multitude of interactions between biological, geochemical, and physical processes? It has been difficult to develop such broad comparative understanding of terrestrial ecosystems, in part due to the complexity of interactions that exist even in single ecosystems, but also due to the lack of appropriate study sites and infrastructures to conduct such research. Yet, knowledge of mechanisms that control geographic variations in function is central to the development of dynamic and unified models of ecosystems and the earth system. For example, recent work has shown that forest carbon balances can be sensitive to external inputs of nitrogen (e.g., many temperate forests), to inputs of phosphorus (e.g., old tropical forests) but – in some cases – remain insensitive to changes in nutrient supply (e.g., some temperate forests in polluted regions). Such dramatic geographic variations in carbon sequestration are fundamentally important, and the underlying mechanisms depend on poorly understood feedbacks between biota, soils, climate, and geological substrates.

2. "Integration of critical earth system processes across broad spatial and temporal scales." It is urgent that we understand how key processes are coupled across spatial and temporal scales within the earth system. While local-scale and short-term processes dominate the proximate turnover of carbon and other nutrients in local environments, many essential ecosystem-level properties (e.g., long-term balances of C and other nutrients, fertility, or sustainability) develop over much larger spatial extents and over periods of decades, millennia, or longer. For example, while emissions of the greenhouse gas methane is controlled at scales of microbes within anaerobic environments, the effects of methane on climate become apparent at global scales, and the dynamic coupling of methane and climate emerges only within millennial-scale atmospheric records such as the Vostok ice core.
3. "Role of human activities and social trends as drivers of environmental change." This area addresses the challenge of how to include people and human activities as integral components of the earth system. A critical problem is that, throughout large regions of the world, human impacts have grown so strong and pervasive that it is difficult to ask questions about processes that control natural behavior of ecosystems in unimpacted areas. Explicit comparisons of impacted vs. less impacted regions of the earth can provide valuable information about magnitudes and mechanisms of human effects. An even more difficult challenge stems from the need to understand the underlying demographic and social processes that control how human activities affect environments. Individual demographic-based approaches are increasingly replaced by models that focus on households, and that incorporate economic, cultural and value-based predictive variables. While such approaches may improve our predictive ability in an increasingly human-dominated world, biogeosciences is far from establishing such links to social and demographic drivers. The committee recommends that the programmatic vision for biogeosciences must, at an early stage, explicitly incorporate comparisons between more vs. less impacted ecosystems, and social/demographic drivers.

While the field of biogeosciences primarily focuses on the basic function of terrestrial ecosystems, such knowledge is essential to applied questions of human impacts on ecosystem function, such as climate change, increased atmospheric levels of carbon dioxide, atmospheric nitrogen deposition, and losses of biotic diversity. As humans increasingly impact the earth’s physical and biological systems, we are engaging in vast, unreplicated experiments with largely temporal dynamics and outcomes. Some human actions, such as the continued release of greenhouse gases or the introduction of non-native plants and animals, may have massive social and/or economic costs. Understanding the ecological and physical mechanisms that underlie such impacts will have tremendous value for the dialog on strategies for preventing detrimental changes, and for adapting to the changes that cannot be prevented.

The questions and approaches outlined here are closely aligned with the current agenda for understanding human impacts on the carbon cycle, and the response of the earth system to climate change. Biogeosciences complements ongoing efforts to measure and model the extant carbon cycle. Critical questions about the mechanisms and interactions that ultimately control how carbon cycles within and among ecosystems can not be answered by a singularly descriptive focus on carbon. Biogeosciences also links to current efforts of understanding the expression of biocomplexity across different scales of our environment.

Biogeosciences offer an intellectual platform for understanding fundamental controls on ecosystem nutrient cycles, including controls by nutrients, water, and biotic composition, feedbacks between climate and plant-soil-atmosphere interactions, and synergistic effects caused by interactions of very different human impacts. The biogeosciences program outlined here therefore provides an important, complementary, and intellectual link to initiatives such as the U.S. Carbon Cycle Science Plan (CCSP)⁷, the U.S. Large Scale CO₂ Observing Plan (LSCOP), the AmeriFlux program, the Free Air CO₂ Enrichment Program (FACE), and the North American Carbon Program (NACP). These close alliances can also benefit research in the biogeosciences, in that infrastructure that is already developed for questions on carbon research (e.g., towers, experiments, or study sites) offer the opportunity to broaden these studies to include basic processes in biogeochemistry and the biogeosciences.

Committee recommendation: The field of biogeosciences should be included as a central and intellectually unique component of the global carbon and global change research agenda. The field offers new research opportunities when linked to allied programs, with particular emphasis on those programs that focus on the carbon cycle.

The integration of biological and geological sciences is further limited by a lack of joint platform-level initiatives for studying land-based ecosystems. The term "platform-level initiative" here refers to larger field-based research efforts that address specific questions of central intellectual importance, and that coordinates the efforts of a large and integrated group of scientists representing different disciplines and/or areas of expertise. The paucity of such initiatives is puzzling given the central role of land-based ecosystems for a number of important large-scale environmental questions. In addition, the intellectual core areas of biogeosciences (discussed above) represent fertile ground for the development of joint collaborative questions and initiatives.

Why are terrestrial-based studies lagging other fields (e.g., ocean sciences) in the development of question-oriented platforms and initiatives? One reason appears to be that interactions among the communities of ecologists and geoscientists have thus far been rare and uncoordinated, with notable individual exceptions such as at the Hubbard Brook Ecosystem Study and/or projects such as the "Large-Scale Biosphere-Atmosphere Experiment in Amazonia". In addition, the tradition of collaborative interdisciplinary research is relatively new to fields such as ecological science. A third reason appears to be that collaborations have mostly focussed on individual sites, with little attempt to understand geographically broad couplings between biological, geophysical, and geochemical processes.

Committee recommendation: It us urgent that ecologists and geoscientists initiate a series of planning meetings with the goal of developing a broad science plan for joint programmatic platforms and specific initiatives. These initiatives should address specific questions of central intellectual importance to the biogeosciences and the earth system.

Examples of such platform topics are included in the three core intellectual areas in biogeosciences, outlined on page 5 above: 1) "Co-development of biota, soils, atmosphere, and climate"; 2) "Integration of critical earth system processes across broad spatial and temporal scales"; and 3) "Role of human activities and social trends as drivers of environmental change." The NSF should consider funding a series of new workshops that bring together the community of biogeoscientists to identify the most important aspects of these platform topics, and to outline the infrastructure needed to address these.

In addition to such question-driven platforms, the committee discussed several infrastructure-based needs:

1. "Natural laboratories:" One of the most interesting ideas for facilitating integration is the establishment of field sites in which biologists and geoscientists collaborate on shared interdisciplinary questions. Such "natural laboratories" can be used in two ways: i) as places whose properties lend themselves to answering fundamental questions; or ii) as places that are previously so well characterized that the broader context of any new measurements is well defined.

The committee discussed the importance of how to locate such "laboratories" to best answer important fundamental questions. The spatial scale of such "laboratories" may vary depending on the particular question – from an individual site, to a local gradient, or to an entire region (e.g., the Great Plains as a laboratory for climate/biogeochemistry interactions). For questions where context is important, there are several networks with infrastructure and historical collections of data throughout North America. Sites in the Long Term Ecological Research (LTER) network are supported by a well-developed scientific infrastructure; the AmeriFlux network monitors and quantifies ecosystem metabolism and carbon exchange at a variety of locations; the U.S. Forests Service forest inventory network documents the distribution and growth of tree species in an extensive number of sites; and a network of "Neon" sites have been proposed as biological observatories.

Committee recommendation: A number of field sites ought to be developed to support joint platform-level collaborations, in which ecologists and geoscientists address questions of fundamental concern to the field of biogeosciences. A future workshop-type meeting should be dedicated to discussing appropriate questions and sites.

2. Other programmatic initiatives: The committee discussed other initiatives, including the development of "technological centers" that can support highly specialized equipment (e.g., esoteric isotopes, aircraft-based flux measurements, etc.) that is central to research at the biology-geoscience interface. A number of models are possible from explicit multi-instrument facilities to funding supplements to individual labs that receive and analyze samples from the broad scientific community. Such centers could also play an important role in training scientists in new techniques. There are many issues to work out, particularly involving reward systems for people who maintain such facilities.

Committee recommendation: It is worth pursuing whether "technological centers" are an appropriate solution for broadening the access to highly specialized equipment, and for training students in the use of this equipment.

By its nature, the field of biogeosciences requires an interdisciplinary perspective that is perhaps unmatched, and that is increasingly embraced by leading academic institutions. This represents both a challenge and an opportunity from an educational standpoint. The challenge is to provide a strong foundation in science to undergraduate and graduate students, in combination with a broad perspective across a range of sciences. The opportunity is to bring new students into science at both undergraduate and graduate levels as is already seen in the growth of environmental science programs around the country. These issues of education are central to training the next generation of leaders in the biogeosciences and to educating students in critical environmental issues. The NSF and other funding agencies have the opportunity to influence and lead the development of novel interdisciplinary environmental science curricula at academic institutions.

Recommendation: The NSF and other funding agencies ought to work with professional societies such as the ESA and AGU, and with representatives from university programs, to explore how best to deliver educational leadership within the biogeosciences.