The Environmental Science and Design Symposium, formerly the Land and Water Symposium, is a multidisciplinary forum that promotes the exchange of ideas related to the resiliency of natural and built systems. This year’s theme, Complexity of Environmental Legacies, reflects the challenges of developing sustainable systems in landscapes transformed by decades of modification and contamination. Speakers from a wide range of disciplines (fashion, geology, geography, architecture, and ecology) will address topics related to urban, sustainability, restoration, and the integration of design with biological systems.
Browse the Environmental Science and Design Research Initiative 2019 Collections
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Ruptured stream anticline pools as Portage Escarpment habitat features
03/21/2019Introduction On Cleveland's urbanized Portage Escarpment, small Lake Erie tributary ravines show degraded anthropogenic aquatic habitats. Escarpment ravines also have small geological features called stream anticlines which, when naturally ruptured, produce channel pools that tend to improve habitat. Problem At the base of deep ravines within the local Devonian shale sedimentary sequence, small, non-tectonic stream anticlines are notable upwarp deformation features. As exposed anticline crests naturally rupture and erode, aquatic pools form within the resident stream channel. Watershed scientists assess such pools as healthy habitat features but do not link them with discreet geological process. Synthesizing from both sciences, a significant Portage Escarpment habitat feature type is proposed. Results In the escarpment ravines of Cleveland's urban Heights, flashy stream flows reduce aquatic habitat to scoured bedrock channels and isolated gravel bars. Nevertheless, where ruptured stream anticlines produce channel pools, habitat assessments (HHEI, QHEI) show higher than expected scores. Ruptured anticline features are herein identified for Devonian sedimentary units within the Doan Brook-Frontal Lake Erie administrative watershed. Significant pool habitat features are enumerated. Conclusion In Portage Escarpment ravines, ruptured stream anticline channel pools are underappreciated aquatic habitat features. When appearing in scoured bedrock channels typical of local urban hydrology, such pools can enhance habitat health. With the systematics of anticline pools in hand, escarpment ravine habitat restorations can better build upon local natural conditions. In any event, ruptured anticline pools should be preserved as natural components in aquatic habitat health.Short-term sea-level fluctuations along the eastern seaboard of the US and their atmospheric connections
03/21/2019In this research, we assess the impact of short-term events, combined with sea-level rise, through synoptic climatological analysis, exploring whether circulation pattern identification can be used to enhance probabilistic forecasts of flood likelihood. Self-organizing maps (SOMs) were created for two discrete atmospheric variables: 700-hPa geopotential height (700z) and sea-level pressure (SLP). For each variable, a SOM array of patterns was created based on data spanning 25°-50°N and 60°-90°W for the period 1979-2014. Sea-level values were derived from tidal gauges between Cape May, New Jersey and Charleston, South Carolina, along the mid-Atlantic coast of the US. Both anomalous sea-level values, as well as nuisance flood occurrence (defined using the local gauge threshold), were assessed. Results show the impacts of both the inverted barometer effect as well as surface wind forcing on sea levels. With SLP, higher sea levels are associated with either patterns that were indicative of on-shore flow or cyclones. At 700z, ridges situated along the east coast are associated with higher sea levels. As the SOM matrix arranges atmospheric patterns in a continuum, the nodes of each SOM show a clear spatial pattern in terms of anomalous sea level, including some significant sea-level anomalies associated with relatively ambiguous pressure patterns. Further, multi-day transitions are also analyzed, showing rapidly deepening cyclones, or persistent onshore flow, can be associated with the greatest likelihood of nuisance floods.Small scale (<10,000 km2) isoscapes reveal spatially variable water sources for northeastern Ohio precipitation, surface water, and groundwater
03/21/2019Water isotopes are a long-standing environmental tracer in hydrogeology, but many studies focus on their variations in time rather than space. Isoscapes are an emerging tool to visualize and analyze the variation of water isotopes at large regional scales. Here we hypothesize that varying influences of different air mass source areas, plus lake effects, have the potential to impart variation in water isotopes at much smaller scales. We test this hypothesis in a 10,000 km2, low relief study area in northeastern Ohio, which receives moisture from Pacific, Arctic, Gulf of Mexico, and Great Lakes source areas. Across the study area, mean annual precipitation ranges from 900-1100 mm and winter snowfall varies from 800 to 2500 mm. Precipitation was collected at two locations separated by 0.5 degrees latitude: one in the area receiving lake effect precipitation and high snowfall (the “snow belt”). Lake, river, and groundwater samples collected from 120 locations seasonally, and 12 locations sampled biweekly. Water samples were analyzed with the Picarro L2130-I analyzer, and precipitation source areas were calculated using HYSPLIT. Precipitation samples have high inter-storm isotopic variability associated with different moisture source areas, as well as seasonal variability. There is also a difference between the precipitation isotopes at the two locations, up to +/- 6 ‰ for δ18O in the winter. At lentic locations, water isotopes are generally more negative in the snow belt, but evaporative effects create additional spatial and temporal variability to the surface water isoscape. Biweekly river samples show both seasonal and spatial variability, with δ18O ranging from -11.6 to -2 ‰. Rivers in the snow belt have a more negative isotopic ratio than rivers to the south. Groundwater samples show little seasonal variability but there is a gradational variance towards less negative isotopic ratios towards the south of the research area. The northeastern Ohio isoscape illustrates.Taxonomical and Functional Heterogeneity of Microcystin-Degrading Bacteria in Lake Erie
03/21/2019Microcystins (MCs) are one among the predominant cyanotoxin in the freshwater environment which are primarily degraded by heterotrophic bacteria. Nevertheless, our knowledge about the taxonomic diversity of MC degrading (MC+) bacteria from Lake Erie is very limited. In the current study we look at forty MC-degrading bacterial isolates screened from numerous bacterial cultures from Lake Erie. These isolates were characterized based on their MC-degradation rates at different pH, temperature and addition of organic carbon. A mixed culture MC-degradation was also performed to further characterize MC-degradation rate for isolates which were taxonomically close. The MC-degrading isolates were primarily gram positive in nature and exhibited an array in terms of color, shape and morphology. Taxonomically they belonged to Alphaproteobacteria, Gammaproteobacteria and Firmicutes phyla. MC degradation rate of the isolates were impacted by temperature and also pH, but remain unchanged with the addition of organic carbon. The MC-degradation rate were also observed to show an increase for some of the isolates primarily belonging to the Pseudomonas spp. in the mixed culture degradation process. These MC+ isolates identified were also found to possess other degradation properties and biological uses according to previous literature.Temporal patterns and Interactions of Bacteria, Algae, and Zooplankton following a Freshwater Reservoir Cyanobacterial Bloom
03/21/2019The frequency and severity of cyanobacterial bloom are at risk of increasing as a consequence of eutrophication and increased water temperature. The elevated cyanobacterial biovolume can have substantial impacts on water ecosystem function by producing toxic secondary metabolites and subsequent induction of hypoxia affecting microbial community structure and biogeochemical cycles. Here we combined 16S rRNA gene sequencing and microscopic cell counting to explore the seasonality and co-occurrence patterns of bacteria, algae, and zooplankton following a reservoir cyanobacterial bloom. During the sampling period, 22 distinct cyanobacteria genus were identified, and the dominant ones were Chroococcus, Planktolyngbya, Aphanizomenon, Pseudanabaena, and Cylindrospermopsis. Our results showed that the bloom event significantly altered the bacterial community composition without affecting the alpha diversity. Time-lag analysis found that the similarities of microbial communities significantly declined with the increase in time-lag. Regression modeling showed that environmental variables strongly affect the distribution of functional profiles, but weakly influence taxonomic composition within individual functional groups. Neutral community modeling revealed that stochastic processes also strongly affected bacterial community assembly, and the fit of the model varied over the sampling period and was the lowest during the bloom. Co-occurrence network analysis showed that correlations between bacterial taxa were predominantly positive, suggesting cooperation interactions might contribute to the stability of the microbial community during cyanobacterial succession. Overall, we concluded that changes in the structure of bacterioplankton are associated with the changes in the abundance and composition of freshwater cyanobacteria.The Changing Frequency of Spatiotemporally-Relative Weather Types across North America
03/21/2019Most climate change research is focused on the trends in different metrics (means, maximums, minimums, extremes, etc.) of temperature and/or precipitation. Beyond this, however, trends in other variables have been noted, including absolute moisture metrics, relative humidity, sea-level pressure and many other atmospheric variables and phenomena. This multivariate nature of the weather at any given location naturally underlies the concept of an air mass or weather type – a category of weather that defines the holistic atmospheric situation at a particular time. Thus, since temperature and precipitation trends over the last few decades are well-researched, but a changing climate can manifest itself in myriad ways, the simple aim of this research is to examine the changes in GWTC weather type (WT) frequency over North America since 1979. Generally, warm WTs (Humid Warm, Warm, Dry Warm) are increasing in frequency at the expense of the cool WTs (Humid Cool, Cool, Dry Cool), and the effects of Arctic Amplification are apparent. Humid Cool weather is significantly increasing in northwestern North America and transitional (frontal) weather types are increasing in the US and decreasing in Canada. The magnitude of changes is greater than we expected (+/- 30 to 40 days in some regions). We postulate that noting the extreme magnitude of the WT frequency changes found herein might be a more efficacious means (than explaining importance of a 2-3°C change) of communicating longer-term climate change trends to policymakers and the general public.