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
Geodesic Filter03/21/2019
This geodesic Dome has vegetation built with the structure. It has microclimate greenhouses on the exterior. The vegetation on the exterior of the building and inside of the microclimates are plants specifically chosen because of their ability to clean the air and create more oxygen. The interior is a research center that focuses on creating more microclimates as well as filtering water pollution with Plants. The parts of the Center is open to the public to educate them like a botanical garden. I am researching what micro climates can survive in Cleveland green houses and what they need to function.
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Getting to the root of soil carbon sequestration: tracking fine root carbon losses and soil carbon gains03/21/2019
Fine roots of woody plants are the greatest terrestrial source of carbon (C) to soils, hence represent a major flux of C out of the atmosphere. While the decomposition rates of many tree species’ roots have been measured in other experiments, such information doesn’t address how much root C is ultimately incorporated into microbial biomass, respired, leached to dissolved organic C pools, or stabilized as soil particulate organic matter (POM). We explored two different pathways by which plant litter becomes stabilized in soil: a physical pathway, where root fragments are protected from decomposition by microorganisms in soil aggregates, and a biochemical pathway, where labile plant tissues are utilized by microorganisms that, in turn, bond with minerals to form stable soil C. In two two-year long decomposition experiments with four tree species’ roots that had contrasting chemical and morphological properties, we monitored losses of root C and gains of C in various soil C pools. Preliminary results suggest that root morphology strongly affects which decomposition pathway predominates. Roots with smaller diameter and specific root length lose more C to fragmentation, becoming occluded in POM, while thicker roots contribute more C to microbial and dissolved organic pools, which have faster C turnover rates. Overall, more root C was stabilized in soil from roots with thin, highly-branched roots. Understanding which plant traits affect a tree’s potential as a C sink is important for improving our accounting of carbon in forests in a changing climate.
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Holocene changes in algal abundance and dissolved oxygen discovered in Sluice Pond, MA through spectroscopy and analysis of a sediment core03/21/2019
Throughout the Holocene, Sluice Pond (Lynn, MA, USA), has experienced fluctuations in algal communities and dissolved oxygen (DO) content based on measurements from a sediment core raised from its anoxic central basin. The variability in the core’s composition can be mapped with Visible Derivative Spectroscopy based on varimax-rotated, principal component analysis (VPCA) through wavelet analysis and by plotting this information against an AMS 14C constrained age model. The temporal history yields a better understanding of the lake’s changing environment and provides insight into the extent of preserved natural and human events. Thirteen separate constituents were present in the core, as mixtures of six different orthogonal (or independent) VPCA components that account for 97.1% of the variance in the data set. Six components were extracted overall, but a detailed look at two is presented in this project. Through the data collected in 6VPCA1 and in 6VPCA6, algal blooms and lake turbidity can be mapped out and referenced against the age model to show changes in relative concentration. The data shows anoxic conditions through the increase or decrease of DO indicators. The first component oscillates on a period of 4 ka, and the second has a 6 ka oscillation. Major climate events such as the Younger Dryas and the 8.2-kiloyear event are represented in the data by a large drop in algal concentrations and an increase in DO during both extreme cold events. Within the last 200 years, fluctuations in algal blooms, turbidity, and DO have increased dramatically in both frequency and extent. Through the data and methods used in this project, we are given a representation of the natural variance over the Holocene and can start to understand how humans may have impacted Sluice Pond. This new information allows for a better understanding of the conditions Sluice Pond has experienced in the past and can inform us on steps that need to be taken for the overall health of the lake.
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How does elevation and/or substrate affect the composition of biocrusts?03/21/2019
Biological soil crusts (‘biocrusts’) are conglomerations of a variety of organisms including bacteria, lichens and mosses that dominate soil surfaces in arid environments. Biocrusts are important in drylands due to their ability to perform several ecological functions such as soil stabilization and increasing pools of available nitrogen. Higher elevations are typically associated with more precipitation and, consequently, higher vascular plant densities, either outcompeting biocrusts or providing optimal conditions for later successional biocrust communities (lichens and mosses). However, the relationship between the abundance of biocrust and elevation may be obscured by soil type and its effects on nutrient cycling. We tested whether there was a relationship between biocrusts and elevation, and whether differences among biocrust communities were affected by soil type and enzymatic activity (a proxy for nutrient cycling). Biocrust samples were collected from a variety of sites along an elevational gradient between Phoenix (300 m) and Flagstaff (2,100 m) in Arizona while targeting different soil types. We measured % cover of biocrusts and the activity of three enzymes associated with carbon, nitrogen and phosphorus cycles. We found a significant effect of elevation on biocrusts. Lichens and mosses were significantly affected by elevation, while cyanobacteria were not. No significant substrate results were observed, except for the avoidance of granitic soils by mosses and avoidance of basalt by lichens. These results indicate that elevation affects the community composition of biocrusts, but perhaps greater sampling efforts are needed to make more general conclusions about the effects of substrate on biocrust composition.
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How pore geometry affects the transition of non-Fickian to Fickian solute transport over various length scales03/21/2019
Pore scale solute transport is known to exhibit non-fickian solute transport characteristics related to pronounced tailing during asymptotic times. The tailing behavior is likely associated with large variability in pore fluid velocity, which is caused by diverging-converging pore channel geometry, and which further is magnified during inertial flows, as eddies or ‘recirculation zones’ form and grow in the dead-end part of pore channels. In this study we, at first, design a series of pore channel geometries and define them with a non-dimensional pore geometry parameter ‘γ’. We use these geometries to solve Navier-Stokes and Advection-Diffusion (ADE) equations and obtain ‘break through curves’. These curves are used to fit analytical solution to ADE and determine the degree of non-fickian to fickian transport characteristics for various range of Reynolds number (Re) flows. Finally, pore channels are systematically extended in the direction of flow to ‘length scales’ where the non-Fickian transport becomes Fickian transport. The relationships between ‘γ’, Re, and length scales for Fickian transport will be presented during the conference meeting.
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Impact of Deer and Soil Chemistry on Plant Mutualists in Forest Soil03/21/2019In temperate forests, understory herbaceous plants are often affected by the abundance of white tailed deer, both directly through herbivory and indirectly through soil compaction. Soil chemistry, particularly soil pH, also has a large effect on the soil microbial communities that influence plant growth and survival. The objective of this study was to study the interactive effects of deer herbivory and soil chemistry on plant mutualists in forest soil using Jack-in-the-Pulpit plants. Jack-in-the-Pulpit are common understory herbs in temperate forests that deer will eat but are not preferred. In Bole Woods at the Holden Arboretum, 760 Jack-in-the-Pulpit plants were planted into 19 plots (both deer exclosures and un-fenced controls), each containing 4 subplots, 3 where soil chemistry had been altered and a control. Soil samples were collected from each subplot to be used for DNA analysis. Using PCR-terminal restriction fragment length polymorphism, we determined community structure of the fungal and bacterial communities. Our results showed that across communities of general fungal, AM fungi and bacteria, there were taxonomic differences present with soil chemistry alteration. Subplots that were amended with limestone and calcium had similar communities compared to subplots that were amended with triple superphosphate or the control. These differences reflected changes in soil pH that we had seen previously. |
Improving Vertical Axis Wind Turbine Feasibility: Predicting Turbine Airfoil Performance Via Wind Tunnel Experimentation03/21/2019
Vertical-axis wind turbines have a unique advantage over traditional horizontal-axis wind turbines, because they can operate at lower wind speeds. These wind speeds are typically encountered during a majority of days in the Midwest region of the United States, as well as other locations in the world. Vertical-axis wind turbine configurations have some significant advantages over horizontal-axis wind turbines. One major advantage is their size, they are small enough that they can be used in a more densely populated urban area; however, performance challenges prevent these vertical configurations from being widely integrated. One possible design solution is a spherical vertical axis turbine, employing a sequence of airfoils on the struts comprising the sphere. The objective of this research is to measure and assess the aerodynamic properties of different airfoils and predict their performance through one complete rotation. Kent State University's subsonic wind tunnel was utilized to collect the airfoil data on two airfoil shapes: the NACA 0012 and NACA 2412, at two low-speed Reynolds-numbers: 50,000 and 100,000. Conventional correction factors and curve-fitting techniques are applied to the experimental data. Using the resulting data, the optimal airfoil placements can be predicted to create a working model for further testing and implications. It is expected that the results of these experiments will assist in improving the performance of vertical-axis wind turbine configurations over a wide range of wind speeds, thus expanding the operational feasibility envelope of wind turbines as important sources of renewable energy.
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In-stream decomposition and macroinvertebrate community dynamics: a comparison between invasive Glossy Buckthorn and native Silky Dogwood leaf litter03/21/2019Invasive species are a major threat to the biodiversity of an ecosystem. Their ability to establish and thrive in foreign habitats and often outcompete natives have led to changes in ecosystem dynamics in both terrestrial and aquatic habitats. However, the influence of riparian invasive plants on adjacent aquatic insect communities is understudied. This is important because riparian zones provide essential leaf litter resources for aquatic communities. To test this question, we studied how aquatic invertebrate communities varied between leaves of invasive Rhamus frangula and Cornus amomum. Leaf litter bags with either leaf type were constructed and deployed into Swine creek allowing aquatic invertebrates to colonize for over three months. No differences in macroinvertebrate community composition between Rhamus frangula and Cornus amomum leaves were observed, however, there were differences in the rate leaf litter decomposition and the numbers of shredders and predators present on the leaf material. The mechanisms behind these differences in decay and invertebrate preference are still not completely understood, however it can be said that with the increased invasion of glossy buckthorn into swine creek’s riparian zone, changes to ecosystem dynamics and potentially the food web may be observed. |
Influence of iron (oxyhydr)oxide crystallinity on phosphate bioavailability in contrasting redox and hydrological conditions03/21/2019
Hydrological shifts can change redox regimes in soils and can form poorly crystalline iron (Fe) oxides that have the potential to adsorb the limiting nutrient phosphate. The crystallinity and mineralogy of the Fe oxides that form as a function of redox fluctuations remain unknown. Phosphate bioavailability may decrease as hydrological changes drive the precipitation of Fe oxides, potentially limiting plant growth. To investigate these complex interactions, an in situ incubation experiment was conducted. Mesh bags filled with Fe-oxides of different crystallinity (ferrihydrite, goethite and hematite) were buried in and around a vernal pond in northeast Ohio. Fe-oxides were either phosphate-free or had high concentrations of sorbed phosphate. Lowland soils in vernal ponds were flooded during spring months but progressively dried out over the summer, while upland soils remained unsaturated, providing us with contrasting redox conditions. Bags were removed at two times intervals to capture flooded and dried conditions in the lowland soils. Redox conditions in the lowland soils shifted from anoxic to oxic as the pond above dried out. Fe-oxide crystallinity, analyzed using x-ray absorption fine structure spectroscopy, decreased over time for oxides incubated in the pond. Phosphate loss from phosphate-added treatments generally followed trends in Fe loss, indicating phosphate was released from dissolving iron oxides. Phosphate-free treatments in the lowlands gained phosphate over time despite losing Fe-oxides, indicating enhanced ability of small amounts of freshly precipitated Fe-oxides to adsorb phosphate. Results from this study will provide insight into the effect of Fe-oxide crystallinity on phosphate bioavailability.
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Innovative Reuse of Alum-Water Treatment Residuals (WTR)03/21/2019
Excess phosphorus levels in water ways can lead to eutrophication. A low cost measure to reduce P levels may be to use Water Treatment Residuals (WTRs), which are otherwise shipped to a landfill or stockpiled in a drying field for blending and future land application. Two WTRs were selected for this study: an alum-based WTR and an alum-based WTR augmented with powdered activated carbon (PAC). Additionally, a study is being performed to investigate if baking the WTR will reactivate surface sites, leading to a greater PO4 uptake. Batch isotherm and column experiments were performed to assess the specific adsorptive capacities. Numerous isotherm trials were planned to compare potential P adsorption within differing conditions. Variables may include different isotherm temperatures, static vs. dynamic desorption, and distilled vs. raw water desorption. The adsorption capacity will then be used to determine the variety of WTR best suited for P sequestration, identifying the amount that would be necessary to run a trial in a tributary flowing into original receiving source waters of the WTR material. Decreasing the P concentration entering the reservoir would aid in the prevention of harmful algal blooms.
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