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
The Impact of the Bokashi Composting Method on Soil Fungal Community Structure and Function03/21/2019
Conversion from traditional farming practices to more sustainable, organic methods is becoming increasingly popular. While widely practiced, little research has been performed on how many of these methods influence overall plant health and their impact on soil microbial communities. In Costa Rica, for instance, many local farms utilize an organic farming technique known as the Bokashi method. This method is an anaerobic composting technique that utilizes the fermentation of organic matter and waste as a means of adding nutrients to soil to increase crop productivity. This is method is not only cost effective, but it is also not as work intensive as traditional composting techniques. However, while this method has great potential and is widely used, the impact that it has on soil microbial community structure and function is still a mystery. In this study, we analyzed whether Bokashi treatments have an impact on fungal community structure within several Costa Rican fields. We sampled soil from cilantro and/or cabbage farms representing a chronosequence of the Bokashi organic farming method, which ranged in age of implementation from 1 – 18 years. After sampling, we utilized next-generation Illumina sequencing to examine fungal taxonomic community structure. Overall, samples were found to contain a diverse array of fungi with dominance of phyla belonging to Ascomycota and to a lesser extent Basidiomycota. We found that the length of time a farm has been organically managed has a marginally significant effect on soil fungal community composition. However, sampling site and crop type had a more significant effect, which may show the importance of surrounding plant cover and dispersal limitation in determining community composition. While our findings suggest a small potential effect of organic farming on community composition, further analysis will be performed on how it influences the distribution of fungal functional groups.
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Understanding biodiversity services in urban and analogous natural systems: the case of green roofs03/21/2019Green roofs provide urban environments and the humans within them with many services, including stormwater management, reduced energy consumption and habitat for organisms. However, due to the physical constraints of many green roof environments, green roof habitats are typically characterized by thin soils experiencing drought, flood, and intense wind and solar radiation. Natural habitats with these characteristics are relatively rare, however, some intact thin soil environments occur in the Great Lakes basin. Our research examines the plant and insect communities arising around these natural and built thin-soil environments, to gain insight into how these habitats contribute service and function to the greater landscape. Insect communities are key contributors to several ecosystem services, including pollination, pest control, and decomposition. Improving our understanding of how insects in these habitats function is important to guide efforts to design structurally-analogous elements intended to deliver services in urban environments. We will sample three functional groups of insects (pollinators, natural enemies and decomposers) in green roofs and natural areas that are similar to green roof structure, while characterizing the plants and other physical attributes of each site. Once identified, we will compare communities between and within built and natural systems of various characteristics, and the functional ecology can be described. Our work will inform design of green roofs to improve biodiversity service delivery in urban environments. |
Understanding how microorganisms influence the bioavailability of iron-bound phosphate under shifting redox regimes in nutrient poor soils03/21/2019Plants remove carbon dioxide (CO2) from the atmosphere and can mitigate climate change, but require nutrients like phosphorus (P) to increase primary productivity and build biomass. P can become limiting to plant growth as changes in the water table alter soil redox conditions. These anoxic-oxic changes can influence geochemical sorption of phosphate (PO43-) to iron (oxyhydr)oxides, modifying P bioavailability. Vernal ponds are one such system that experience seasonal hydrologic changes that result in redox fluctuations. Release of iron-bound phosphorus through microbial mechanisms could increase P bioavailability for plants to grow and in turn take up more CO2. To assess how microbes affect the availability of P in iron-bound PO43-, we examined P uptake by the microbial community in vernal pond soils in Northeast Ohio. Mesh bags were filled with organic material and three types of synthetic iron oxides (ferrihydrite, goethite, and hematite). Iron oxides were either saturated in a PO43- solution or not sorbed with PO43-. Bags were incubated in both lowland (pond) and adjacent upland environments and removed during flooded conditions and after the pond had dried. Preliminary results show that bags in both environments that contained iron-bound PO43- had higher mass following incubation than those without PO43-, suggesting biomass accumulation. Release of iron-bound PO43- could supply plants with vital nutrients needed to grow, resulting in greater uptake of atmospheric CO2. |
Using Crowdsourced Data to Analyze Patterns in Odonate Phenology03/21/2019
The influence of long-term climate change on phenology for insects of the order Odonata (dragonflies and damselflies) has been well documented in several parts of the world, showing a negative correlation between emergence date and temperature. Likewise, previous studies have shown that spring-emerging species, with an overwintering diapause, are more susceptible to climate change than those species emerging later in the summer. This study analyzed the responsiveness of local odonates by utilizing data gathered from a recently established, ongoing biodiversity inventory of Odonata residing on the campus of UVA-Wise in Wise, VA. Odonates collected in Spring 2015 experienced a much colder winter than the specimens collected in 2017 which allowed for the testing of links between any earlier emergences and warmer temperatures. If winter temperatures increased, then it would be expected that adult odonate emergences will occur earlier in the year. First capture dates for 24 species of spring-emerging odonates were compared for 2015 and 2017 and these first capture dates served as a proxy for emergence dates. The statistical analyses revealed that the 2017 first capture dates are significantly earlier than the 2015 dates (p = 0.036) for just the damselflies. This link observed here between temperatures and earlier emergences for damselflies, but not with dragonflies, is for a very limited scope and time frame, but is consistent with other research linking the effects of climate to larger-scale patterns specifically just for damselflies.
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Using VPCA Analysis to Determine Impact of Main Contaminants in Euclid Creek03/21/2019Villa Angela beach in Northeast Ohio has been closed multiple times over the past decade due to high influxes of E. Coli bacteria. Problems often arise after large rain storms due to the flooding of multiple combined sewer overflow systems feeding into the streams of the Euclid Creek watershed and being deposited off the shore of the beach. This project is an attempt to use discharge data to assess times of high flow and assess the content and contamination influx of these dates using specific remote sensing techniques. Landsat-8 images were combined with the KSU spectral decomposition method of image analysis, which employs varimax-rotated principal component analysis (VPCA) to determine the main contributors to the water’s overall content and their interaction with the aquatic systems in the lake and around the mouth of the creek. This more cost- and time-effective method can reduce potential biases in traditional remote sensing techniques by separating individual components based on their respective spectral fingerprints and comparing against a known library of spectra. |
What are the effects of nutrient addition and competition on the growth of Juniperus virginiana?03/21/2019The eastern redcedar Juniperus virginiana is the most widespread conifer in the eastern United States. J. virginiana is a range-expanding (encroaching) species that is native to the United States. This species contributes to the decline of grassland biodiversity because it competes with native species for nutrients, resources and changes the landscape of the areas where it encroaches. In Ohio, J. virginiana is particularly abundant on limestone-derived substrates, either because this species prefers to grow on limestone or due to the absence of competition with other species. We are interested in investigating the factors that are most important in facilitating the encroachment of J. virginiana into new areas. We tested the effects of nutrient content, high pH, and interspecific competition with a common invasive grass (Bromus inermis) and a native tree (Quercus stellata) on the growth and survival of J. virginiana seedlings. We recorded J. virginiana and Q. stellata height and trunk diameter weekly as an estimate of seedling quality and performance. We found that J. virginiana seedlings competing with the invasive grass B. inermis grew more slowly than J. virginiana growing without B. inermis or J. virginiana seedlings with the post oak Q. stellata. In addition, there was a negative effect of limestone addition on J. virginiana growth rate. Our results suggest that J. virginiana does not prefer high pH soil, but rather it thrives in these soils to minimize competition. Future efforts will determine if competition is the main factor affecting the encroachment of J. virginiana into new habitats and areas, which in turn will assist efforts to control woody encroachment into grasslands. |