BES II Project Outcomes

What's This All About?

Second story bays, Charles Village neighborhood, Baltimore.  BES LTER Photo.

BES, as a Long-Term Ecological Research project, is funded in six year increments.  BES II actually lasted for seven years due to a change in the scheduling of the grant cycle by the National Science Foundation (NSF).  We are obliged to produce a formal report to NSF that summarizes what we have done and what its broader impacts are.  This report is technical, encyclopedic, and detailed, and we will make it available when it is finished.  However, NSF also requires us to prepare a "plain language" summary which is posted on the Research.Gov website.  For the interest of the BES community, I'm posting that "Project Outcomes" report here.

A Premier Urban Research and Education Platform

Over the last seven years, the Baltimore Ecosystem Study (BES), Long-Term Ecological Research project has consolidated as a comprehensive, multidisciplinary platform for urban socio-ecological research.  It has demonstrated that concepts fundamental to mainstream ecology, such as the ecosystem, the watershed, and the shifting patch mosaic, help to understand the linked, human-natural components of cities, suburbs, and exurbs.  The knowledge generated has helped educate citizens and students about nature and natural processes in cities.  BES results have helped managers and policy makers 1) to identify new opportunities for urban watershed management, 2) to enhance urban tree canopy and its benefits, and 3) to employ ecological processes and amenities in neighborhood revitalization.  An important product is a new classification of urban land covers that combines social, physical, and biological features.

Sarah Ann Street, west Baltimore.  BES LTER Photo.

Knowledge About Ecosystem Processes

BES has produced new knowledge about urban stream behavior, documenting their disconnection from floodplain and ground waters.  It has shown increasing salt pollution in streams the long-term, and shown the effectiveness of stormwater “best management practices” in old residential neighborhoods.  Findings of stream research focused watershed management beyond the near-stream zone, and subsequent research on urban tree canopy documented reduced exposure to UVB radiation and reduction of the urban heat island effect.  The urban heat island has been shown to be very patchy in its potential negative effects on people, and hotspots of urban heat are distributed inequitably throughout the metropolis.  Other pollutants beyond heat are also patchy, with nitrogen deposited from traffic exhaust being both higher in general magnitude than expected, and concentrated around travel corridors.  The capacity of the urban system to absorb carbon (C) dioxide has also been documented, and daily and weekly patterns confirm the relationship of C dynamics to the activity patterns work and travel.  The vegetation in Baltimore results in less release of C to the environment than would occur without trees and lawns.

Biodiversity and Spatial Dynamics

The biological organisms other than people also have important roles in the urban ecosystem.  The identity of some animals has been homogenized across different cities, as expected, but local specialization still exists.  Urban soils contain a rich community of native and introduced species that contribute to soil metabolism and to the absorption of carbon dioxide and nitrates, taking these polluting compounds out of circulation.  New communities of aquatic animals establish in the novel habitats of stormwater detention ponds, and provide nutrient cycling services and support foodchains.  Notable members of some aquatic habitats are the introduced mosquitoes that can transmit West Nile virus (WNV) from birds to people.  The composition of mosquito communities shifts from rural to urban waters and containers, increasing the risk of WNV in the city.  Birds have been shown in other cities to depend upon the wealth of neighborhoods, but in Baltimore bird diversity responds to the structure of the tree canopy in different neighborhoods. 

Socio-Ecological Processes

BES research has evaluated other important interactions between the social and the biological ecology of Baltimore.  BES social scientists have discovered how the distribution of environmental "goods," such as parks and street trees, has changed over time in Baltimore, and how access to these amenities has varied among different groups.  Results show that African Americans in Baltimore today enjoy a high degree of access to parks and playgrounds compared to African Americans in other U.S. cities.  Examination of the history of environmental zoning variances documented inequitable decision making in Baltimore's past.  However, our research also shows that Black Baltimoreans are the beneficiaries of an "inherited" landscape.  In fact, a long history of segregation, both formal and informal, limited African American access to parks and playgrounds until large numbers of white residents left the city in the 1950s and 1960s.  It was only then that the city's black population "spread out," gaining access to park facilities once considered off limits.  An unexpected legacy of segregation is the contemporary association of toxic release inventory sites with white, working class neighborhoods.  Although areas of greater tree cover have less crime, not all residents consider urban trees to be an amenity.  For decades, both black and white residents of East Baltimore have opposed municipal tree-planting efforts.  In contrast, neighborhood associations during the first half of the 20th century were adept at attracting amenities, such as new street trees, while keeping out unwanted land uses.  BES social scientists adopted the theory of market segmentation to document the role of lifestyle differentiation as a key to understanding the shift from an industrial to a knowledge and service based economy in Baltimore. 

Riparian sycamore along the Gwynns Falls.  Photo by Charlie Davis.

Broader Impacts

The findings of BES have contributed to education of underserved communities, ecological urban design and planning, and discovery and valuation of ecosystem processes within the urban matrix from city to exurb.  Most fundamentally, BES has documented the existence and mechanisms of ecosystem processes in complex urban environments.  The BES research platform is poised to help inform, evaluate, and educate about the sustainability initiatives now being implemented in the Baltimore metropolitan region.

Swamps and the City: Part II

A special guest post by Prof. Grace S. Brush, Johns Hopkins University.

My last post discussed how the role of people in shaping the swampy systems of the Everglades had been erased.  That erasure paralleled how biophysical processes had in the past been ignored in thinking about urban systems.  Because Baltimore is a coastal city, it occurred to me while I was writing that post, that there were insights about the role of swamps and wetlands in the history of our city that would be worth exploring.

Prof. Grace Brush

Who better to lead us on that exploration than Professor Grace S. Brush, one of America's leading paleoecologists -- a scientist who studies past environments and the ecological networks that existed within them, usually by using fossil pollen or larger preserved parts of plants or animals?  Here is her essay, reminding us of Baltimore's important swampy heritage, and the implications for the Chesapeake Bay that result from the reduction or obliteration of those many swampy features. S.T.A.P.

THE VERY WET PRE-COLONIAL LANDSCAPE OF THE CHESAPEAKE BAY, by Prof G.S. Brush

            A prevailing question today, as the historical fish harvests of the Chesapeake and other aquatic systems are greatly diminished, is “What was the land really like, when the water was clear and seafood abundant? 

             Pollen and seed records in dated sediment cores indicate a forested landscape 300 years ago with most herbaceous plants belonging to wetland species.  Pre-colonial soils exposed along river cuts contain water lily pollen. Sedge seeds were common in the sediment.  Rainfall runoff  was minimal in a pervious forest  floor rich in leaf litter and decomposing wood.  Hence groundwater was constantly recharged, creating wet soggy ground.  Seeds of submerged macrophytes in cores collected in present day tidal fresh water marshes record open water at those locations in pre-colonial time. 

Beaver landscape (Morgan 1867)

Historical maps published in 1897 show springs at the mouths of many tributaries.  Druid Hill Park in Baltimore City has structures built for drinking water for horses at sites where ground water surfaced.  They are now dry. Upland trees such as black locust and species of oak are replacing wetland species like green ash and box elder on floodplains of many streams.  This phenomenon, which we have described as a “hydrological drought” is being reported in various parts of Eastern and Midwestern USA.  All through the watershed, a very large beaver population created many marshes behind the numerous dams they built on inland streams  All of the evidence points to a wet environment characterized by many marshes, swamps and ponds.

Baltimore, 1792, with agricultural clearing.

             Within a very short time following colonization, much of the watershed was converted to agricultural land, accomplished by cutting down the trees and draining and filling in wetlands and marshes.  This conversion was facilitated by the near extinction of the beaver population by the fur trade in the 18^th century.  The soil that eroded from the less pervious agricultural land -- along with fertilizers -- was transported by streams to estuarine waters.  Excess nitrogen, a major constituent of fertilizers, is particularly harmful because of its many potential transformations in the soil and water, making it available for generations of plant growth.  It can be removed from the system only by denitrification, where nitrogenous compounds are converted to elemental nitrogen and returned to the atmosphere.  Denitrification occurs almost entirely in wet, anaerobic environments, such as marshes and swamps.  The pre-colonial landscape, which was ideally suited for denitrification, was destroyed as nitrogen loads and sources increased.

Baltimore 1801, showing extensive, wet lowlands.

            Along with overfishing, the transformation of the landscape from wet to dry contributed directly to the fishery decrease in the Chesapeake Bay, as nitrogen not recycled to the atmosphere became a major contributor to increased eutrophication, anoxia and habitat loss in the Bay ecosystem.

Grace S. Brush, PhD, Department of Geography and Environmental Engineering, Johns Hopkins University, Baltimore MD

The map of the beaver dams is from Morgan, L. H.  1867.  The American beaver and his works.  New York: Burt Franklin (reprinted 1970).

Baltimore Mayor Dixon Announces Sustainability Goals

With the announcement on Wednesday, December 3rd, of the overview of recommendations from Baltimore Mayor Sheila Dixon’s Sustainability Commission, the region enters an exciting and important time. The jurisdictions directly responsible for the majority of the Baltimore metropolitan region, including not only the City of Baltimore, but Baltimore County and the State of Maryland, now have visions for sustainability. As environmental researchers encompassing ecology, social sciences and economics, who contribute to the Baltimore Ecosystem Study research program, we are immensely encouraged by this commitment to sustainability.

Sustainability is a goal for society that seeks to insure the social, economic, and ecological health and adaptability of our shared environment. Health of this three part, unified system is important because it is the source of the environmental, social, and economic resources and services we all depend on for sustenance and well being. Adaptability is an important part of sustainability because it is not realistic to keep systems from changing. Events like cycles of wet and dry weather, severe hurricanes, economic cycles, shifting locations of investment, social disruption, and new social interactions all can cause unexpected changes in our cities, towns, and the surrounding countryside.

For sustainability to be a reality, three things are key. One is good knowledge about the environmental processes the rest of the system depends on. The Baltimore Ecosystem Study is a research and education project that helps complement the knowledge generated and managed by municipal, county, and state agencies. Although traditionally each agency, say, parks, public works, or housing, has some of the key data and expertise, sustainability requires knowing how the system as a whole works. This is why coordinating activities with the goal of sustainability in mind is so important. It provides a way for seemingly separate agencies and indeed separate jurisdictions to work together to promote the current health of the Baltimore ecosystem.

The second key for sustainability is to understand how this whole metropolitan system might respond to different ecological, social, and economic changes in the future. Here especially is where the Baltimore Ecosystem Study may reinforce and complement the activities of the different agencies and governments. By providing scientific information and contributing to a socially motivated dialog, the research and education we are charged to accomplish can help policy makers, managers, and citizens to understand how their decisions can influence sustainability.

The third key is political will. With the announcement of the recommendations of Mayor Dixon’s Sustainability Commission, an important part of the puzzle for facilitating the health and adaptability of the Baltimore region falls into place. It identifies a suite of actions that are both relevant to people’s daily lives and for improving the quality of life in Baltimore City’s neighborhoods. But it is also a symbol of political will. Without that, no amount of scientific information will be of any use. Combining the thinking, planning, and activities aimed at promoting sustainability that now exist in the city, county and the state, the Baltimore region can become a national model for linked sustainability of city, suburb, and countryside.