How Does a Long-Term Study Adjust Its Framework while Preserving Data Integrity?

Long-term ecological research is faced with seemingly contradictory constraints: It must maintain a consistent stream of rigorously comparable data over time while at the same time responding to conceptual and theoretical changes in the disciplines underlying those data.  How can such opposing  constraints be reconciled? 

BES has faced this challenge in developing its most recent proposal.  It was required to shift from a framework that -- although it highlighted a frontier topic in the understanding of social-ecological systems -- proved to be problematical for many readers.  In response, members of the project management team took a step back and sought ways to improve the conceptual framework.  First, they wanted to simplify the conceptual framework.  Second, they wanted to increase its parallelism with frameworks of other LTER sites.  Finally, they wanted to emphasize the interactions on multiple scales that caused the changes in urban social-ecological systems over time.

This stepping back took us to the foundations of BES.  The project was founded to examine the basic biophysical structures and functions in an urban system, and how they interacted with social processes, all in a context of change. 

The Founding Ideas of BES

So the founding question of BES asked: How do biological and social patch dynamics combine to shape and change a metropolitan area?  This question was operationalized by applying the watershed concept in a city-suburban-exurban matrix, and by examining nested hierarchies of social, biological, soil, and hydrological processes as potential causes of urban change. 

In revisiting the framework, we looked at what the first three phases of BES had accomplished, and what they suggested about refinements in the concepts.  Furthermore, we looked at the improved understanding of climate change and globalization that had developed over the nearly 20 year history of BES, to see what those insights suggested about revision of our framework. 

New Pressures in the System

It was clear that effects of climate change through sea level rise, increases in storm intensity and frequency, risk of drought, increase in heat waves, and shifts in species ranges were likely to alter the structure and functioning of our urban ecosystem.  Furthermore, globalization was likely to alter human migrations, increase the pressure from introduced and/or invasive plants, animals, pests, and diseases, as well as work continuing social-demographic changes within our region.  These ideas had not played significant roles in the initial conceptualization of BES, which was concerned primarily with testing how well ecological approaches worked in an environment where they had not been tried previously.

Conceptual Refinement about Urban Ecosystems

An additional refinement emerging from BES and other urban social-ecological research also played a role in the evolving framework.  Early on, leaders of BES and its sibling LTER, the Central Arizona Phoenix project, had pointed out the difference in studying ecology in the city versus studying ecology of the city.  The latter approach required an integrative, interdisciplinary stance and investigated all habitats in an urban-suburban-exurban matrix, not just the conspicuously green patches. 

Taking ecology of the city seriously generated a new land cover conceptualization and classification, and required examining the intimate feedbacks between social and biophysical processes over various temporal scales.  Indeed, the urban ecosystem is now seen as "coproduced" by natural and social processes, and consequently, to possess a hybrid social-ecological-technological structure (Rademacher et al. 2018).

Key Features of a New Framework

These insights, empirical advances, and conceptual refinements have led us to propose a new framework to support our continued collection and analysis of long-term data in the urban ecosystem.  The framework divides the research concerns into 1) exogenous drivers of change, 2) the structure of the urban ecosystem, consisting of biological, physical, constructed, and social components, and 3) the functional responses of the urban ecosystem.  All of these aspects -- drivers, structure, and responses -- interact with each other through time.  In addition, the functional responses of the urban ecosystem feed back onto its structure.  In a system that includes humans as individuals, groups, and institutions, the feedbacks may involve learning and adaptation or adjustment.

Exogenous Drivers. 

Exogenous drivers are those that originate or are controlled from outside of the local or regional urban mosaic.  Climate change is clearly exogenous, as are regional patterns of atmospheric deposition of gasses and particulate pollution.  Much of the economy of urban regions is driven by national and international investments, policy, allocation of jobs, and movement of resources and commodities.  Governance anchored beyond the city, such as requirements of regional compacts, state law and regulation, federal regulations, and private-public interactions, can affect a metropolis or its parts.  Technology emerging elsewhere may also alter the fluxes of matter and energy available to a city, and human population can be altered by regional, national, or international migration numbers and directions. 

Some of the factors enumerated as "exogenous" may, if they are managed or shaped within the city or metropolis, act as local or endogenous factors.  It is the origin and distance which determines exogeneity, not the specific type of flux or influence.  For example, the movement of people within a metropolis could reflect local environmental perceptions, behaviors, and organizational networks.

Ecosystem Structure. 

Exogenous and internal influences come together in the structure of the urban ecosystem.  Like all human ecosystems, urban areas consist of the biological organisms and the physical environment, but also of the various human and social structures, and the constructed environment.  The interactions among these four components drive the functional responses of the urban ecosystem.  All four urban ecosystem components are reflected in the ecosystem function.

Functional Responses. 

The functional responses are divided into three linked process realms, long used to organize BES data collection. Watershed biogeochemistry addresses the amount and content of water flowing through constructed infrastructure and biophysical features of catchments.  Local ecosystem production and nutrient transformations are driven by the biota, represented by plant, animal, and microbial communities. These are indexed by key sentinel species.  Human environmental perceptions, behaviors, and the actions of organizations constitute the social functions of the urban ecosystem.  Clearly, all three functional realms interact with each other.  Equally clearly, the functional interactions feed back on the structural filter by which external drivers impact the system.

Similarity with Other LTER Site Frameworks

This new framework is intended to be readily interpretable by ecologists working outside of urban areas as well as those who focus on urban places.  In fact, the general schema for the framework is very similar to that of the Hubbard Brook Ecosystem Study LTER, located in the forests of the White Mountains of New Hampshire.  Hubbard Brook is one of the oldest LTER projects, and focuses on understanding the dynamics of forested watersheds under the influence of exogenous factors and local management choices and ecological succession.  Exogenous factors are well illustrated by the Hubbard Brook study, where acid rain from distant sources was first identified in North America.  Current examples of climate changes include the role of reduced snow cover, and intensification of winter storms.  Of the existing LTER sites, the vast majority include some sort of exogenous factors in their roster of drivers.  Climate change, sea level rise, and human generated land use change are commonly identified as exogenous drivers.

Accommodating Long-Term Data 

For nearly 20 years, BES has collected continuous or repeated data sets on climate and weather, watershed hydrology, nutrient export,  water quality, biodiversity and key biotic populations, soil processes, land cover and land use, social structures, and social dynamics.  These data sets are arrayed across the seven core areas required of urban LTER sites, as stated in NSF's original request for proposals in 1997 (Table 1).

Table 1. Major BES research areas and their distribution across the LTER core research areas.

BES has revised its conceptual framework by identifying the fundamental ecosystem structures and processes represented by its ongoing, long-term data collection, while at the same time organizing the structures and processes differently than in its original conception.  In this way, we hope to have clarified the big ideas that motivate and tie together the data streams emerging from a still under-studied ecosystem type.  The framework combines some of the most fundamental ideas from ecosystem science with the novel structure and large changes represented by urban systems.

Steward Pickett and Emma Rosi

Background Literature

Cadenasso, M. L., S. T. A. Pickett, and J. M. Grove. 2006. Integrative approaches to investigating human-natural systems: the Baltimore ecosystem study. Natures Sciences Societes 14:4–14.

Pickett, S. T. A., M. L. Cadenasso, E. J. Rosi-Marshall, K. T. Belt, P. M. Groffman, J. M. Grove, E. G. Irwin, S. S. Kaushal, S. L. LaDeau, C. H. Nilon, C. M. Swan, and P. S. Warren. 2017. Dynamic heterogeneity: a framework to promote ecological integration and hypothesis generation in urban systems. Urban Ecosystems 20:1–14. DOI: 10.1007/s11252-016-0574-9

Rademacher, A., M. L. Cadenasso, and S. T. A. Pickett. 2018. From feedbacks to coproduction: Toward an integrated conceptual framework for urban ecosystems. Urban Ecosystems. DOI: 10.1007/s11252-018-0751-0

Zhou, W., S. T. A. Pickett, and M. L. Cadenasso. 2017. Shifting concepts of urban spatial heterogeneity and their implications for sustainability. Landscape Ecology 32:15–30. DOI: 10.1007/s10980-016-0432-4

A Presentation on BES III: Research, Education, and Engagement from the Sanitary to the Sustainable City

By now, friends and members of BES are familiar with the new research strategy we have developed to guide our third grant cycle.  A new six year grant is an opportunity to keep up important long-term measurements and experiments, but is also a chance to make important changes.

The fact that the Baltimore metropolitan area has several jurisdictions that have generated substantial, broadly based sustainability plans suggested that one change BES should make was to study how those sustainability efforts in fact changed the social-ecological dynamics of the city, suburbs, and countryside as a linked system.  Earlier posts in the Director's Corner laid out the planning process that led to this decision.  Other posts described the proposal and the strategy it embodied.

Now I have posted a narrated slide presentation on Nature Precedings that gives an overview of BES Phase III.  To hear the narration, use the PowerPoint version.  The PDF version will just have the slides.  The presentation does violate the YouTube rule:  It is long, about 20 minutes.  But for those who like slides, and who enjoy being walked through them, have a look.

Here's the link:

http://precedings.nature.com/documents/6499/version/1

Here's the via Digital Object Identifier (DOI):
http://dx.doi.org/10.1038/npre.2011.6499.1

Here's how to cite the narrated presentation:

Pickett, Steward. Introduction to the Baltimore Ecosystem Study, Long-Term Ecological Research Project, Phase III. Available from Nature Precedings (2011)

BES Renewal Process

Planning for Renewal – BES-3

Planning for the renewal of BES will involve working meetings and white papers. A series of six meetings will be held before submission of the BES LTER renewal proposal in February 2010. Each meeting is envisioned to be a day long event. The Mid-Term Review of BES conducted in 2007 provides necessary background. The review team’s report and the NSF Program Officer’s letter are at http://www.beslter.org/internal/frame8-stuff.html (see heading “Renewal Material” and its subheading “2006 Mid-Term Site Review”).

Product – Each meeting will produce a white paper as a contribution toward the renewal proposal. The required content of the white paper is given after the descriptions of the meetings and schedule, below.
Participation – All Co-Principal Investigators, Post Docs, Graduate Students, and agency and partner Collaborators are invited and encouraged to attend the meetings.

Goals and Strategies – All meetings should:
1. Be primarily product oriented;
2. Result in a referenced white paper as input for the renewal proposal;
3. Employ a few synthetic presentations as stimulus for discussion;
4. Be designed to emphasize discussion rather than presentation;
5. Employ the LTER Network’s Integrated Science for Society and Environment feedback model template (Figure 1);
6. Seek to integrate social, and biophysical realms of research;
7. Identify and state the integrated theory motivating activities to be proposed for the renewal;
8. Articulate integrated modeling and quantitative approaches; and
9. Highlight opportunities for teaching and for educational research that emerge from the theme of each meeting.

Meeting Topics and Schedule

Individual Meetings with Agency Stakeholders. Three representatives of BES met with Baltimore City, Baltimore County, and Maryland State sustainability officers and other decision leaders in October 2008. We explored how to establish a regular communication to exchange information of mutual interest about research, projects, and policy. The insights from these meetings will be used to design an ongoing process for BES to identify shared concerns and opportunities for interaction with policy, management, and decision leaders in the Baltimore region. Leaders: Morgan Grove, Steward Pickett, and Mary Washington.

Meeting 1 -- October 14, 2008:
Scoping the Renewal Process.

The BES Steering Committee, consisting of all Co-PIs and BES Collaborators met to share thoughts on the five conceptual areas to organize the renewal proposed at the 2007 meeting. The feedback loop (Figure 1) that will be an important conceptual tool for planning and organizing BES-3 was also presented. The structure and goals of the white papers, and the consideration of teaching and education research opportunities in each planning meeting were reviewed. Attendees were asked to study the Mid-Term Review report and the notes from the 2007 Steering Committee meeting concerning components of new theory for BES-3, as well as the LTER Network’s model template for Integrated Science for Society and Environment (ISSE) to prepare for the Steering Committee discussion.

Meeting 2 -- January 23, 2009:
Environmental Change and Environmental Inequity.

The issues of global change is significant for Baltimore, as is the differential impact of current and future environments on different social groups. BES-3 must address climate change directly, and identify the ecosystem services that might be altered by changing climate. Measurement of those ecosystem services, and how they can alter environmental hazard and vulnerability, and consequently, environmental justice should be proposed. Explicit measures of each of these features of the urban ecosystem should be identified and justified. Leaders: Larry Band and Kirstin Dow

Meeting 3 -- April 16, 2009:
Land Change Scenarios and Locational Choice Modeling.

The changing structure of urban areas is a key topic for BES-3. A task before us is to develop scenarios for land cover and land use change. The relationship of land change scenarios to models of locational choices that households and firms might make, and the social and economic drivers of those choices will be identified and specific approaches identified and justified. How policy interacts with scenarios can also be explored. Leaders: Mary Cadenasso and Elena Irwin

Meeting 4 – June 23, 2009:
New Hydro-Ecological-Social Theory.

It is crucial to articulate a new generation of integrated theory covering the various major disciplines that constitute BES. Several areas should be considered as a framework for a new statement of the theory unifying BES-3: 1) An urban stream continuum theory; 2) Controls on ecosystem flux and retention; 4) New social theoretical framework; and 4) Theoretical and conceptual approachs addressing coupling and feedbacks between social and biophysical components of the metropolitan system. The mainly biophysical theory should, in cooperation with social scientists, articulate both the expected social-economic drivers and social-economic effects of urban stream continuum and flux theory, while the mainly social theory should, in cooperation with biophysical scientists, articulate the hypothesized biophysical drivers and effects. Here is where education theory that justifies education research or pedagogical methodologies should be articulated and related to the physical-ecological-social theory that emerges. Leaders: Sujay Kaushal and Austin Troy

Meeting 5 -- October 20, 2009:
Integrated Sampling Strategy

Integration across the multiple disciplines within BES can be enhanced by a clearly articulated sampling strategy that spatially and temporally relates the various social and biophysical samples. Options to be explored are the reconciliation of our current different sampling strategies, complementing the existing strategy by new spatial arrays, or articulating a sampling design essentially de novo. This meeting should produce a fully annotated map for one to several sampling strategies that take advantage of our existing data base while advancing sample integration in BES-3. How the sampling strategy can support teaching and education research should be explored. Leaders: Peter Groffman and Morgan Grove

Meeting 6 -- November 17-18, 2009:
Writing Team Working Meeting

A small group will take on the task of preparing the renewal proposal based on the insights from the planning meetings. The leaders of the previous five meetings and other key BES members will convene at the Cary Institute in Millbrook, New York, in order to draft an integrated proposal for BES-3. This meeting will be a focused, intensive writing session lasting two days. Leader: Steward Pickett

BES-3 Renewal Proposal White Papers

Each of the five preparatory meetings listed above will produce a white paper. The meeting conveners will be responsible for organizing the drafting of the paper, and will involve other contributors as needed and available. The papers should satisfy the following goals: 1) State a clear theoretical motivation for work to be conducted in the third phase of BES; 2) Identify clear relationships between social and biophysical topics; and 3) Suggest the key feedbacks between social and biophysical realms to be investigated.

The components of each white paper should be as follows:
1. Title. A conceptual orientation should be emphasized. Titles for these components of BES-3 should be phrased to engage potential reviewers.
2. Research Questions. What research questions have been addressed to date in BES? Briefly, what has been learned? What new questions or outgrowths of the previous questions should be addressed in the renewal? Where do these new or extended questions fit in the LTER social-biophysical feedback loop (Figure 1)?
3. Motivations for the Questions. What explicit theoretical, methodological, and practical motivations are there for each research question suggested? What well known and cutting edge literature supports the theory, methodology, or practical concern?
4. Key Variables. What are the key variables to be measured to answer the questions? How will scenario generation and future projections be supported by the variables suggested? How can the variables from social and biophysical realms be related?
5. Sampling Plan. What sampling plan supports the suggested research questions? How does this exploit the existing BES sampling array? What future changes to the sampling regime are required? How does this sampling plan support the integration of biophysical disciplines, different social disciplines, and the relationship of biophysical and social research? Draft maps of the suggested sampling regime must be included.
6. Anticipated Findings. What outcomes are expected? What theoretical advances are likely? What methodological advances can be served? What practical contributions can be supported? How does the plan contribute to quantifying the feedbacks in the LTER social-biophysical loop (Figure 1)?
7. Illustrative Material for the draft proposal, such as figures, conceptual diagrams, tables, and brief text boxes can be used to summarize and support key points of the argument of the white paper.
8. Executive Summary. A brief (ca. 200 words) abstract or bulleted summary should be prepared to assist the writing team.
The white paper for each meeting will be due one month after the meeting.