As landscapes become increasingly urbanized, there is an associated increase in impervious cover. Impervious surfaces, such as roads, rooftops, and parking lots contribute to the physical, hydrological, chemical, and biological alteration of stream systems. Biotic assemblages consistently degrade with increased watershed impervious cover; however, at low levels of impervious cover, these assemblages exhibit wide variability in biotic integrity. This study investigated which reach- and watershed-scale factors explained biotic condition (i.e., richness, flow traits, thermal traits, and tolerance for macroinvertebrates and fishes) at similar levels of low imperviousness. The primary objective was to identify factors that confer resistance for biota, such that they retain high biotic integrity at low levels of impervious cover, and, conversely, to determine which factors make biota more vulnerable to urban disturbance, such that they have low biotic integrity despite low levels of impervious cover. Forty sites were selected across Massachusetts within two narrow bands of impervious cover: 1–4% (n = 20) and 7–10% (n = 20). Models with reach-scale variables (reflecting habitat heterogeneity, flow, temperature, or water quality) or watershed-scale variables (representing natural characteristics, land use, flow alterations, and other measures of urbanization or impervious) explained additional variance compared to models with impervious cover alone. Reach-scale factors tended to explain more variance than watershed-scale factors for all biotic responses except fluvial fishes, with overall more variance explained for fish than macroinvertebrate assemblages. At the reach scale, colder water temperatures, higher dissolved oxygen, and more large wood were related to higher proportions of fluvial, coldwater, and intolerant fishes. For macroinvertebrates, warmer water temperature, smaller sediment size, and higher nitrate were related to higher macroinvertebrate richness and tolerance. At the watershed scale, air temperature emerged as an important predictor for both taxonomic groups and across response metrics; air temperature was highly correlated with high-elevation watersheds. Other important watershed-scale predictors were open water and dams, flow alteration, and other urban measures such as housing density, impervious in a 120-m buffer, and road crossings. Restoration should focus on strategies to reduce impacts that would degrade in-stream conditions that allow for higher biotic integrity, such as habitat heterogeneity, more large wood, and colder water temperatures. Similarly, watersheds should be prioritized for protection with those characteristics potentially more resistant to urban disturbance, such as high-elevation regions that retained high biotic integrity despite higher dam density, more road crossings, and more flow alteration.

The thesis deals with use of hyperspectral data from APEX and AISA sensors for detection and classification of anthropogenic materials in the areas of Čáslav, Rokytnice nad Jizerou and Harrachov. The main goal is to propose methodology for the detection and classification of roof materials and road surface materials based on established spectral libraries. Another goal is to evaluate applicability of spectral libraries for classification, to compare possibilities of hyperspectral data with larger and smaller spectral range and to create maps of anthropogenic materials above. The methodological approach including masks of anthropogenic materials for roads surface materials and roof materials creation, settings of four classifications algorithms (Linear Spectral Unmixing, Multiple endmember spectral mixture analysis, Spectral Angle Mapper, Spectral Information Divergence) parameters and assessment of classification results, is in the methodology part. The results are visualized and evaluated using overall accuracy and percentage of classified pixels. Finally the results are compared with existing studies and possible improvements for further research are proposed. Powered by TCPDF (www.tcpdf.org)

"Abstract. Urbanization has a significant impact on water quality. Urban drainage systems and impervious surfaces accelerate the delivery of pollutants from land areas in watersheds to streams and rivers. The harmful pollutants include sodium and chloride associated with the application of road salts during the winter, metals and oils associated with vehicles and impervious surface. The goal of this project was to access impacts of urbanization on River Meadow Brook and validate a chloride assessment tool. The first phase of this research was a part of a chloride study sponsored by the Massachusetts Department of Environmental Protection (MassDEP). The second phase of the projects included flow and water quality monitoring. The first phase of the project involved the development of a linear regression equation to validate a chloride assessment tool that MassDEP had developed and implemented based on historical data. River Meadow Brook, a Massachusetts stream that flows from a non-urban, rural area with relatively low pollutant concentrations to highly urbanized area in Lowell, MA, was chosen for that purpose because of the area’s large concentration of roadways and highways and historically high concentrations of chloride. Water samples and continuous conductivity data were collected for a 7-month period. Using 24 grab samples analyzed at the United States Environmental Protection Agency (USEPA) laboratory in Chelmsford, MA, the model was validated with 99.37% confidence using a linear regression equation. Therefore, the relationship between conductivity and chloride was validated. Calculated chloride was used to identify chloride violations of ambient water quality standards in River Meadow Brook. In addition to MassDEP study, the relationship between the percent of imperviousness and various trace metals, anions and total suspended solids was developed to show impacts of urbanization on the stream. The research approach included collection of both water samples and flows to calculate daily pollutant loads. Water monitoring included grab samples and unattended continuous conductivity with a 30-minute recording intervals. Discharge monitoring included collection of flows in River Meadow Brook using a brad- crested dam and the area- velocity technique. A wide variety of cations from a sampling of 5 sites along River Meadow Brook were analyzed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Cl, sulfate and nitrate were analyzed using the Dionex ICS-2100 Ion Chromatography System. Laboratory results of water quality parameters showed that pollutants associated with impervious surface increase as the stream flows from its headwaters to downstream. The result from the Pearson correlation analysis revealed that sodium, chloride, potassium, vanadium, nickel, copper, arsenic, TSs and pH had a positive relationship with imperviousness while DO and nitrate had negative relationship. The combination of laboratory and field analysis helped to assess the impacts of urbanization and checked against ambient water quality standards. "

Impervious surfaces negatively affect urban hydrology by altering the depth, frequency and seasonal distribution of stormwater runoff. To assess the imperviousness of green roofs, a mathematical model was developed to simulate the stormwater response of a hypothetical green roof. The model is based on the physical processes that affect the green roof stormwater response and uses historic climate data. The results show that green roof imperviousness fluctuated according to climate conditions and precipitation sequence. Only 29% of the total precipitation received by the green roof resulted in runoff, however, the response varied substantially when evaluated at a daily interval. Runoff was eliminated during 82% of days with rain and a higher proportion of runoff disturbances were eliminated during the spring and summer compared to the fall. In comparison to an impervious surface, the green roof showed a reduction in the depth and frequency of runoff thereby improving urban hydrology.

Problems with storm water runoff are becoming more frequent, and the main cause is the increase of impervious cover (IC). The imperviousness increases stream peak flows, changes peak times, and so changes the flood distribution. Several policies are used to manage flows and flooding; however most have been reported to be inefficient because land owners do not have correct exposure to price incentives and risk. The main contributions of this thesis are an investigation into market mechanisms to price and allocate impervious cover allowances, while managing flood distribution. The market mechanisms are based on the electricity and gas markets which use linear programming formulations. This thesis develops three net pool market mechanisms: Det_MarketIC is a capped and deterministic market for IC, and Sto_MarketIC and Sto_MarketIC_Risk are stochastic market models with flood component penalties and risk positions representing the desired risk from the community respectively. Additionally, a gross pool market was extended under rainfall uncertainty, Gross_MarketIC. The market design is an auction system with operational constraints and bids for IC allowances from participants. The system relates physical routed flows at nodal or control points to these bids. The models clear the market by creating a demand (supply) curve for increments (reductions) in flows at specific places, and accounts for marginal changes in the expected flood damage and flood damage components. The market formulations estimate efficient allocations and prices. Decomposed prices from the market models are shown based on duality, as applied in electricity markets. The dual prices show spatial and temporal effects of flows, which impact at flooding areas. With Sto_MarketIC and Gross_MarketIC, prices account for changes in flood distribution. With Sto_MarketIC_Risk, prices also account for the risk as CVaR in flooding areas. Thus, prices increase as binding risk conditions are tightened. Finally, the net pool models are illustrated using hydrological and hydraulic simulators based on a small catchment located in Canterbury, New Zealand. Allocations and prices varied with the different models. Participants would face increasing prices in their IC allowances due to increments in flood damage.

Numerous research studies have been conducted on the modification of weather and local climate by the urban environment. In studying the urban environment effects, researchers have investigated the urban heat island (UHI), anthropogenic cloud condensation nuclei, anthropogenic heat emissions and other factors. Many of these studies used data sampling networks, while other studies relied solely on computer modeling. This research has taken an approach between the sampling network studies (which were often limited in spatial density) and the pure computer model studies (which lacked the benefits of observational data) to investigate the Tampa Bay Region UHI. The research utilized inexpensive commercially available temperature logging sensors within a 525 km² study area. One hundred temperature logging sensors, deployed within the study area, generated in excess of 250,000 time and temperature data points for analysis. The large number of temperature sensors enabled the generation of detailed spatiotemporal maps of the Tampa Bay Region UHI. Analysis of the data revealed a significant relationship between the percentage of impervious surface in the study area and the intensity of the local UHI delta temperatures. In addition, the analysis identified the existence of micro UHIs within residential areas. These micro UHIs affected readings within the residential areas. In conjunction with the investigation of the relationship between the percentage of impervious surface and the generation of a UHI, wind speed's role as a moderating factor was also investigated. It was found that increases in wind speed are correlated with a lessoning of the observed UHI. Wind speeds above approximately 2 ms-1 exhibit a significant negative relationship to the development of a UHI. The results of this study add to the field of UHI research in subtropical environments.

In recent years, green roofs have become an accepted solution in ecological urban design to mitigate the impacts of impervious surfaces (Berghage, Beattie, Jarrett, Thuring, & Razaei, 2009). An experimental research project was conducted at the Mississippi Agriculture and Forestry Experiment Station (MAFES) Green Infrastructure Research Area at South Farm of Mississippi State University to determine how medium depth and slope gradient on rooftops affect plant cover and survival. Plant cover was monitored monthly by photographing the experimental green roof platforms. Photoshop and AutoCAD software programs were employed to digitize and to calculate plant cover from the images. All recorded data was analyzed with Analysis of Variance (ANOVA) tests. It was determined that the effects of medium depth and slope are statistically significant on plant cover and survival.

To address accuracy concerns of the National Land Cover Dataset (NLCD), this case study compares impervious surface from the NLCD to a Detailed Land Cover Dataset (DLCD) for the Town of Blacksburg, Virginia over two time periods (2005/2006 and 2011) at spatial aggregation scales (fine to coarse) and scopes (site-specific to area-extent). When comparing the total impervious surface area, the NLCD overestimated the DLCD by appreciable amounts (12-27%) for the entire town and across all specified land use zones for both time periods examined. A binary pixel-wise accuracy assessment of impervious surface revealed that the NLCD performed well for all scopes except for the single family land use zone (user accuracy <40%). The spatial aggregation of pixels to 90-m led to improved agreement between the two datasets. Using the DLCD as a reference, an empirical normalization equation was successfully applied to the NLCD to further reduce overestimation and data skewness. / Master of Science

There is currently a great need to expand the understanding of land use policy’s impact on water quality. The purpose of this thesis is to examine local policy in place in Covington, Louisiana in order to find out if it is having an impact on land use, which then has an impact on water quality. Methods used included reclassification of land use categories within a Geographical Information System and analysis of changes in the city over a four year period. Policy was assessed using a pre-existing evaluation method from The Center for Watershed Protection as well as by a more flexible instrument developed by staff and faculty in the Department of Landscape Architecture at Mississippi State University. Three water quality parameters were examined for impairment due to their known correlation to urban runoff. It was determined that Covington’s water quality related policy is insufficient and is having little effect to curtail the types of development occurring within its boundaries. Impervious cover within the city is rising and surface waters both within and around the city are impaired.

It is well documented that urbanization changes the hydrology of watersheds (Hammer 1972; Booth 1991; Rose and Peters 2001). Increases in runoff volume and velocity from urbanization result in stream channel degradation (Hammer 1972; Henshaw and Booth 2000; Walsh et al. 2005; Leopold et al. 2005a; Poff et al. 2006). While stormwater management measures may be implemented to reduce the impact of stormwater runoff on streams, these practices do not reverse stream channel degradation that has already occurred. Stream restoration utilizing Natural Channel Stream Design (NCD) techniques is an effective way to reverse the effects of urbanization and return natural function to a stream. The design (bankfull) discharge for an NCD stream restoration project is the cornerstone of a restoration design. Existing methodologies for determining design discharges, such as hydrologic modeling and bankfull identification, have not worked well for NCD stream restoration projects in urban watersheds. The use of hydraulic geometry relationships serves as an alternative method for determining design discharge, but the required information is not generally available for urban Northern Virginia streams. However, rural regional curves developed for the Maryland piedmont, adjusted for watershed impervious area, provide a means to determine design discharges for urban stream restoration projects in Northern Virginia. / Master of Science