Vogt, J. M., G. B. Epstein, S. K. Mincey, B. C. Fischer, and P. McCord. 2015. Putting the "E" in SES: unpacking the ecology in the Ostrom social-ecological system framework. Ecology and Society 20(1): 55.http://dx.doi.org/10.5751/ES-07239-200155

Trees provide numerous benefits for urban residents, including reduced energy usage, improved air quality, stormwater management, carbon sequestration, and increased property values. Quantifying these benefits can help justify the costs of planting trees. In this paper, we use i-Tree Streets to quantify the benefits of street trees planted by nonprofits in three U.S. cities (Detroit, Michigan; Indianapolis, Indiana, and Philadelphia, Pennsylvania) from 2009 to 2011. We also use both measured and modeled survival and growth rates to “grow” the tree populations 5 and 10 years into the future to project the future benefits of the trees under different survival and growth scenarios. The 4059 re-inventoried trees (2864 of which are living) currently provide almost $40,000 (USD) in estimated annual benefits ($9–$20/tree depending on the city), the majority (75%) of which are increased property values. The trees can be expected to provide increasing annual benefits during the 10 years after planting if the annual survival rate is higher than the 93% annual survival measured during the establishment period. However, our projections show that with continued 93% or lower annual survival, the increase in annual benefits from tree growth will not be able to make up for the loss of benefits as trees die. This means that estimated total annual benefits from a cohort of planted trees will decrease between the 5-year projection and the 10-year projection. The results of this study indicate that without early intervention to ensure survival of planted street trees, tree mortality may be significantly undercutting the ability of tree-planting programs to provide benefits to neighborhood residents.

Redline mapping was adopted by the Home Owner’s Loan Corporation (HOLC) in the 1930s to help assess its lending risk based on observable characteristics in urban neighborhoods across the United States, but the practice has been criticized for evident racial discrimination in addition to financial risk assessment. Researchers have demonstrated that modern urban tree canopy cover is lower in the historically redlined zones of four US cities. This article focuses on Indianapolis, Indiana, where a HOLC map was developed in 1937. Analysis using a geographic information system (GIS) was conducted in order to detect evidence of ecological legacies of redlining. Using this method, evidence of relatively high-intensity development, low greenspace and forest cover, and disproportionately high incidences of brownfield sites, Superfund sites, industrial waste sites, and Interstate highways were detected in historically redlined zones in Indianapolis. While opportunities for further and more detailed research are considered, the method employed here should be developed such that it is replicable for other cities with redlining histories in Indiana and other surrounding states with comparable spatial datasets. This example protocol can be adopted and refined by various stakeholders to establish where the need may exist for programmatic solutions and to better inform policy recommendations.

The social-ecological systems framework was designed to provide a common research tool for interdisciplinary investigations of social-ecological systems. However, its origin in institutional studies of the commons belies its interdisciplinary ambitions and highlights its relatively limited attention to ecology and natural scientific knowledge. This paper considers the biophysical components of the framework and its epistemological foundations as it relates to the incorporation of knowledge from the natural sciences. It finds that the Missing ecology 433 mixture of inductive and deductive reasoning associated with socially-oriented investigations of these systems is lacking on the ecological side, which relies upon induction alone. As a result the paper proposes the addition of a seventh core subsystem to the social-ecological systems framework, ecological rules, which would allow scholars to explicitly incorporate knowledge from the natural sciences for deductive reasoning. The paper shows, through an instructive case study, how the addition of ecological rules can provide a more nuanced description of the factors that contribute to outcomes in socialecological systems.

Streams and forests are ecosystems connected through hydrology, but few studies have looked at the connectivity between streams and forests in the context of urban development. City-made decisions affect connections between streams and forests by isolating both ecosystems. Streams are often channelized or buried to increase potential development areas. Forests often become fragmented and may be removed unless protected. Historical choices in land usage affect the sites and sizes of current urban streams, forests, and development. This affects the distribution of impervious surfaces, which separates streams from forests. Despite these barriers to stream/forest interactions, cities can experience stream/forest connectivity. Seven Bloomington watersheds are ranked on their proportions of buried streams, channelized streams, forested hydrology, forested streams, urban forest patch cover, and impervious surface cover, along with the historical presence of urbanization. Watersheds demonstrate stream/forest connectivity, with five watersheds containing 50% or greater forested stream segments. Bloomington canopy cover reduces stormwater runoff by approximately 127 kiloliters per year. These forested areas reduce flooding, reduce nutrient loading, and reduce stream conditions associated with urban stream syndrome. Understanding urban stream/forest connectivity can improve green infrastructure design and green space design, which improve urban resilience and better connect residents to the environment.