Urban Long-Term Ecological Research (LTER) sites have a
special mission within the National Science Foundation’s portfolio, and among
the two dozen LTER sites. All LTERs are
obliged to conduct research that seeks to understand the status and changes of
five core ecosystem processes: 1) primary production, 2) the flow of inorganic
matter, 3) the flow of organic matter, 4) study of important populations, and
5) natural disturbance.
Of course, urban systems have crucial human and social components, as well as the artifacts and effects of social processes. Consequently, the two urban LTERs must
additionally be concerned with long-term 6) changes in land use and land cover,
along with their ecosystem effects, 7) monitor the effects of
human-environmental interactions, using integrated approaches to linking human
and natural systems in an urban ecosystem environment, and 8) integrate
research with local K-12 educational systems.
Although BES III is motivated by novel theoretical concerns,
as enumerated below, we wish to indicate how BES is achieving what may be
considered our charter requirements from NSF.
The report for any given 12 month period is restricted by NSF to
activities and outcomes for that period only.
So this report is not a cumulative summary of BES contributions.
One important point is that the activities and findings do
contribute to our BES III conceptual structure, but the report is not divided
to show that. Those insights will be
made available elsewhere. For the BES III
conceptual structure, see http://beslter.org/frame4-page_2.html.
The 2013 Annual Report is divided as 1) Activities, 2)
Findings, and 3) Contributions. New
publications are available in on the website, and can be found by sorting by
date in the publications browser http://beslter.org/pubs_browser.asp.
Activities in Core Research Areas For Urban LTERs
Primary Production
Production was measured in aquatic microfilm
communities. Tree production is measured
every five years in the 195 point random sample of plots used to parameterize
the Urban Forest Effects (UFORE) Model.
Flow of Inorganic Matter
Innovative modeling tools were developed for parcel scale
stormwater flows. This includes
developing workflows and adaptation of process models for fine resolution,
built environment influences on water routing at the parcel and streetscape
scale.
The nitrogen budgets for nine, main BES watersheds across
the urban-rural gradient were updated to refine estimates of (
Inputs -
Outputs)/
Inputs for each
year between 1999 and 2010. These
improvements in the budget will better expose the role of land use, and the
influence of climate on N retention.
The stream stage sensing equipment was upgraded at Pond
Branch, a small forested reference watershed, in anticipation of the need to
improve accuracy in stage readings and continuous discharge in all BES small
watersheds.
Flow of Organic Matter
Carbon storage densities for trees, and the total for urban
forests were estimated based on new data for 28 cities, including Baltimore.
Population Studies
Mosquito populations were sampled across the growing season
and by life stage in city neighborhoods of contrasting socio-economic status,
and along the 9 sampling sites of the Gwynns Falls watershed. Several mosquito species in Baltimore are
important human disease vectors, and are sensitive to both aquatic and
terrestrial environmental conditions that vary across urban-rural gradients and
that are expected to differ based on social features of neighborhoods.
The application of metacommunity theory as an organizing
principle for long-term data on terrestrial and community composition and distribution
was expanded. Research tested the
hypothesis that urban landscape structure mediates both local and regional controls
on species richness. Assessments of 209
woody plant communities, representing remnant and disturbed sites, included
residential, commercial, parks, and vacant parcels. Plankton community data were collected along
with physiochemical information, and a mesocosm experiment was initiated to
determine the interaction between nutrient loading and algal management
practices. Sediment coring in urban
stormwater ponds was used to reveal the temporal trends in species
assembly.
Monitoring of earthworm populations continued in both rural
reference and city park sites. These
species are influential in soil structure and nutrient processing.
Long-term monitoring of breeding bird populations continued,
and a second year of winter bird data was added.
Disturbance
BES metacommunity research seeks to go beyond the common
lumping of all urban habitats as “disturbed” to refine the understanding of
environmental perturbations, stresses, species dispersal and priority effects,
and legacies of various kinds of human management, including community gardens and
minimally managed vacant lots.
Human Land Cover Change and Ecosystem Effects
Urban-rural transitions are notoriously complex, and so are
not well quantified. A statistical
methodology that uses commonly available spatial data in a novel way was
developed and applied.
Human-Environment Interactions
The history and geography of zoning was documented in order
to understand when and why zoning regulations were passed, and to identify the
major drivers in the efforts to segregate land uses and people.
A new method for analyzing the effects of pharmaceutical and
personal care products (PPCPs) in situ
was developed. The effects of PPCPs and
illicit drugs on microbial biodiversity and function along the urban rural gradient in metropolitan
Baltimore were documented via field survey and controlled experiment. The role of illicit drugs in streams is a
large knowledge gap.
In order to understand key aspects of the social structure
of environmental decision making in the region, analyses of data on the
interactions of environmental stewardship organizations in Baltimore was
completed.
The relationship of tree cover and identity of the managers
of tree cover were determined for neighborhoods based on social and economic
differences. The role of human behavior
and neighborhood characteristics on lawn fertilization were assessed.
Integration with K-12 Education
Organizational
Connections. To institutionalize BES
educational curricula and support continued greening efforts on school
campuses, BES education specialists participated in the Baltimore Public School
Green School Network. BES supported a
Research Experience for Teachers fellow in 2012-2013, and with leveraged
funding supported a Teacher-In-Residence from Oregon.
BES Teachers’
Institute. Participants in the BES
2012 Teachers’ Institute and 2012 RETs participated in a further five, one-day
professional development sessions during the 2012-2013 school year. The 2013 summer BES Teachers’ Institute engaged
teachers new to BES in a 7-day workshop that included not only science but
math, social science, and art teachers.
The participants in these programs become part of a lasting community
supporting science education in urban schools in Baltimore, and connect that
community with national resources and support persons.
Student Learning. A leveraged project (NSF MSP) is allowing us
to conduct significant, long-term and cross-site research about how students
think and learn along key strands of an environmental literacy learning
progression. Extensive research took
place during this past year as part of the work of the Carbon, Water,
Biodiversity and Citizenship Strands of the Pathways project. Students and teachers completed “tests” to
describe their thinking about key ideas in these subject areas, and student
interviews were carried out to complement the written tests.
Ecology Teaching. BES collected rich and deep data during the
teaching of one of the instructional units for each teacher, videotaping 4-5
class sessions, interviewing teachers before, during after the unit and at the
end of the school year, interviewing and surveying students, and collecting
artifacts from students and teachers.
These data, along with information about student and teacher learning
from the Pathways environmental science literacy assessment, are helping us
describe the connections between professional development, teacher knowledge
and practices, and student engagement and learning.
Findings in Core Research Areas For Urban LTERs
Primary Production
Primary production in aquatic microfilms is influenced by
the presence of pharmaceuticals and personal care products in Baltimore
streams. Fourteen species of trees, of a
total of 20 measured, declined in Baltimore over the period 2001-2005. The cover of all tree species in Baltimore
declined by 1.9% over that period.
Flow of Inorganic Matter
Modeling demonstrated that fine scale dynamics and
processing for drainage at parcel and streetscape scales is a critical
component of the water and nitrogen retention processes in the built
environment.
N retention is significant in the city and suburban
watersheds, although this is likely to decrease with climate change and further
urbanization. This is in contrast to the
common expectation that retention of limiting nutrients in urban watersheds
would be low.
Finalization of the 2012 water year stream data allowed the
significance of long-term trends extending for at least 10 years to be assessed
for the first time in BES. Different
major watersheds across metropolitan Baltimore exhibited contrasting annual
mean flow dynamics, with Gwynns Falls being slightly lower than the long-term
averages, while the subwatersheds of the Gunpowder Falls had flows ca. 20%
greater than average.
Flow of Organic Matter
Carbon storage densities for trees, and total urban forests
were estimated based on new data for 28 cities.
Urban whole tree carbon storage densities averaged 7.69 kg C m-2
of tree cover and sequestration densities averaged 0.28 kg C m-2 of
tree cover per year in Baltimore. Baltimore
carbon storage density averaged 8.76 kg C m-2 with net sequestration
of 0.168 kg C-2 yr-2.
Population Studies
The survey of mosquito populations found seventeen (17)
species to breed in Baltimore, with only six (6) being found regularly. The four most abundant species included two
vectors of West Nile Virus, Culex pipiens,
and C. restuans, and two invasives, Aedes albopictus, and Ae. japonicus.
Terrestrial and aquatic metacommunity analyses revealed high
variation in species turnover across space (i.e., high beta diversity). Patterns of spatial turnover suggested that
human preference for species composition over species richness is the
predominant driver of urban beta diversity.
Diplocardia zicsii,
an earthworm species new to science, was described from Baltimore.
Disturbance
The composition of phytoplankton communities in stormwater retention
ponds has shifted in response to the disturbance represented by algal
management, with an increase in generalist versus strict herbivorous
species. Unmanaged ponds exhibited more
variable species assembly dynamics, whereas zooplankton in managed ponds were
more influenced by immigration from the regional species pool. Initial analyses of plant communities in
vacant lots demonstrate that legacies of demolition and of remnant gardens
influence the beta diversity.
Ongoing soils research has discovered that anthropogenic
factors, such as management, appear to overcome natural foil forming processes
by increasing pH and nutrient concentrations in the surface 0-5 cm of urban
soil profiles.
Human Land Cover Change and Ecosystem Effects
Urban-rural transition zones can be divided into three
subzones, depending on land cover, imperious area, multivariate assessments of
distance and accessibility variables, and geographically weighted regression
coefficients. A suburban transition is
distinct from rural land, and is especially associated with the presence of
buried streams.
Human-Environment Interactions
Mosquito population dynamics showed clear interactions with
human behavior and associated physical structures. In June, 82% of containers in the lower
socio-economic status neighborhood contained mosquito larvae, compared to only
38% of containers in the higher socio-economic status neighborhoods. By late July, the frequency fell to 66% in
the lower socio-economic status location, but rose to 38% in the higher
socio-economic status neighborhood. The
results that larger, more permanent breeding habitats support larger
populations of biting adults by mid-summer.
Many refuse containers, such as cups and tires that supported larvae in
June were dry by late July. However,
gardens and yard care, which were more common in the higher socio-economic
status neighborhood, were more likely to maintain larval habitat. Of 16 stormwater management structures
sampled in 2012, pupal density was positively related to intensity of urban
development.
Common drugs found in BES streams have the potential to
influence the function and structure of aquatic microbial communities. Aquatic microbial communities in urban
sampling stations were less sensitive to pharmaceuticals and personal care
products than rural stations. Triclosan
concentrations in Baltimore streams have the potential to lead to resistant
bacteria and can change bacterial species composition.
Social analysis of networks of environmental organizations
revealed 607 organizations participating in stewardship activities in the
city. A follow up survey indicated that
the stewardship network is mixed sector, but that non-profits dominated,
accounting for nearly 80% of the groups.
Baltimore environmental organizations and citizens define stewardship in
social rather than ecological terms, with religious, mostly Christian, values
often used.
Indicators of lawn maintenance, such as mulching, pruning,
presence of lawn, and presence of large trees, were associated with lower rates
of crime, an important refinement beyond previous results based on tree cover
alone. Residential litter correlated
positively with crime. Transportation
availability and bike lanes were associated with increased property values,
although causality remains to be determined.
Integrate with K-12 Education
BES education research has discovered that some
middle school students, and a few more high school students have moderate
levels of environmental science literacy, while most hold only rudimentary
levels. Teachers tend to be a bit more
sophisticated in their understanding but the majority still don’t demonstrate
the highest level of understanding as measured by our assessments. Student and teacher literacy can be improved
with hands-on activities that foster active learning and critical building of
knowledge upon the base that learners start with.
Teachers received training in environmental and social
science research and teaching techniques
and learned the results of BES education research into student thinking
and learning. The Teachers’ Institute
centered around concepts of 1) learning progressions; 2) principle- and
evidence-based reasoning; and 3) any place on Earth is an ecosystem.
Contributions within Principal Disciplines
The study of beta diversity is one of the first to examine
the mechanisms of between-habitat compositional turnover, rather than just the
roles of local and of regional diversity in understanding urban biodiversity.
The novel, parcel based hydrological flow models and the
associated workflows are applicable to urban systems generally, and fills a methodological
gap.
The new methodology for assessing the effects of
pharmaceuticals and personal care products (PPCPs) in situ is a contribution to the broader understanding of this
understudied suite of contaminants in urban streams. The associated demonstration of the effects
on aquatic primary producers alerts researchers to the potential for these
widespread contaminants to be important in urbanized watersheds more broadly.
Data collected by the bird monitoring project are count
data. Work with colleagues from the MU
Department of Statistics is developing new Bayesian mixed model procedures for
estimating count data.
Contributions to Training
The annual field safety and Baltimore orientation workshop trained
BES graduate students, postdocs, undergraduates and Urban Resources Initiative
college interns.
Materials on communicating science in various venues, media,
and formats are made available to BES undergraduates, graduate students and
postdocs (http://besdirector.blogspot.com/2011/04/insights-from-bes-communicating-science.html). Science writing, writing for
the public, communicating with reporters, communication with policy makers, the
use of video and photography, and professional presentation strategies are
among the topics presented.
BES research and educational curricula were integrated into
Parks & People’s educational and youth career development programs,
KidsGrow (elementary grades), Project Blue (middle grades), and BRANCHES (high
school grades). These programs serve the
predominantly minority populations of Baltimore City in particular. KidsGrow reached 220 students in 2013.
A Research Experiences for Teachers (RET) fellow
participated in a 6 week intensive research program mentored by a BES
scientist. The fellow is a science
teacher at Independence School Local 1 in Baltimore.
The project continues to provide valuable experience for
newer USGS staff in (1) techniques for measurement of streamflow in small
watersheds, some of which are in remote areas, (2) comparing stream flow
conditions in small watersheds of differing land use, including urban,
agricultural, and forested, and (3) evaluating flow conditions along an
urban-rural land use gradient at 4 main stem stream gages in the Gwynns Falls
watershed.
Cooperation with the Maryland Department of Public Safety
and Correctional Services in our biodiversity research adds an instructional
and training outcome through a novel citizen science approach improves the
statistical power of our research.
Contributions beyond Science and Engineering
N retention results are relevant to new Watershed
Implementation Plans (WIP) put in place to achieve goals set by new Total
Maximum Daily Load (TMDL) regulations.
The statistical assessment of hydrological extremes made
possible by the extension of the BES long term stream flow record to 10 years
allows them to be included in regional hydrologic analyses and to be useful to
regional water policy and management.
The coupled groundwater-surface models linked to BES are the
first truly 3-D hydrologic model of this region. It can be employed to answer questions about
water residence times and fluxes on a large regional scale.
BES data on the concentrations of Pharmaceuticals and
Personal Care Products as well as illicit drugs and their residues in Baltimore
streams has informed policy makers and water quality managers of the importance
of a relatively neglected category of contaminants in streams. In addition, knowledge that these chemicals
can influence stream productivity and function may help guide policy decisions.
Collaborative work leveraged NSF LTER and Cyberinformatics
funding to develop sustainable software for watershed ecohydrological management
that facilitates interaction, through crowd-sourcing, with residents and
communities.
The influence of suburban tree cover spatial pattern on ecohydrology
and runoff production can be simulated, visualized and used as a management
strategy that incorporates residential preferences. This provides a useful urban design and
restoration tool.
Refined methodologies for assessing urban tree carbon
storage and sequestration at the state and national level are relevant to
climate change policies and attendant management strategies in place in the
Baltimore region.
Interactions with the Baltimore City Office of
Sustainability have confirmed the relevance of several of our data streams and
engagement activities with six of the seven major components of the official
sustainability plan. BES researchers are
in frequent communication with the Office of Sustainability concerning specific
action targets and monitoring strategies.
Engagement with communities, non-profits, and government
agencies has produced several positive outcomes:
• Greening of
public school campuses.
• Integration with the City Mayor’s
Office to transform vacant City-owned properties into community managed green
space; supported the Baltimore Community Green Space land trust.
• Provided technical and scientific
information to community gardeners and other greeners through the Community
Greening Resource Network.
• Support for the Urban Waters Federal
Partnership by implementing several Growing Green projects; shared data on
community managed green spaces with Baltimore Indicators Alliance who developed
an interactive online map for community use.
BES continues to explore linkages between science and art
both as a stimulus to creativity in the sciences and as a medium of
communication with non scientists. The
2013 BES Artist-In-Residence was Patterson Clark, who in addition to being a graphic
artist, writes an environmental blog for the Washington Post. He prepared a graphical interface, ultimately
to be installed on the BES website, as an engaging portal to BES research and
education for the general public.