Browsing by Subject "Wetlands"
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Item Considering the importance of wetlands to hunter-gatherer adaptation : a microbotanical investigation of Late Pleistocene plant-use in the Eastern Levant(2015-08) Nicolaides, Monica Lorelle; Rosen, Arlene Miller; Denbow, James R.; Wade, Mariah D.; Butzer, Karl W.; Olszewski, Deborah I.The distribution and composition of ecological opportunities had a tremendous impact on Late Upper Palaeolithic to Middle Epipaleolithic (ca. 28-14.5 ka cal. BP) (Late Pleistocene) hunter-gatherers, influencing the ways they chose to use, modify and manage the changing Levantine landscape through and after the Last Glacial Maximum (ca. 28-19 ka cal. BP). The main objective of this dissertation is to employ phytolith and micro-charcoal analysis to explore through direct evidence, the long-term patterns of Late Pleistocene hunter-gatherer plant-use in the Eastern Levant. The phytolith data presented in this dissertation demonstrates clearly that wetlands are vital to understanding Late Pleistocene hunter-gatherer adaptations in the Eastern Levant during the late Pleistocene. This new direct archaeobotanical evidence shows that Late Pleistocene hunter-gatherers employed flexible local systems of plant-use that focused on wetland resources. Through their exploitation of anthropogenically sensitive phytolittoral resources, Late Pleistocene hunter-gatherers may have facilitated the development and expansion of those resources and contributed to the social and ecological feedbacks that aided the ‘upward mobility’ of wetland resources. In providing a dependable food and craft resource repository, wetland plant resources may have facilitated increasingly sedentary adaptations in certain locales and perhaps permitted increasing use of risky grass and cereal resources. This understanding of Late Pleistocene plant-use and human-environment dynamics veers significantly from previous perspectives on hunter-gatherer plant-use in the region. Firstly, in considering the local ecological opportunities, this work emphasizes the complexity of gathering strategies and the choices hunter-gatherers faced in the Late Pleistocene. Secondly, by seeking a new ethnographic analog in the American Great Basin, a region defined by its characteristic wetland/dryland landscape, it was possible to hypothesize about the many types of hunter-gatherer wetland adaptations in the Eastern Levant. Thirdly, by employing phytolith analysis a different picture of plant-use emerges from that which focuses on macrobotanical remains alone. Moreover, because macrobotanical remains are so rare in most Epipaleolithic contexts, this phytolith data constitutes the most complete botanical record for this important period in the Eastern Levant. This new perspective helps shift the emphasis from cereal and small-seeded grass (SSG) use and the broad-spectrum revolution (BSR) narrative that has overbearingly dominated our understanding of Late Pleistocene hunter-gatherers. Lastly, informed by an understanding of human-environment interactions based in Historical Ecology and Human Niche Construction (HNC), this dissertation recognizes that Late Pleistocene hunter-gatherers did not just react to their environments, but created and modified their environments. This research critically reconsiders the way we see hunter-gatherers in the prehistory of the Levant.Item Constructed wetlands for agricultural wastewater treatment(Texas Tech University, 1998-08) Ancell, Michael EdwardA 23-tank, 43 m , pilot-scale constructed wetland system was loaded daily with 136.2 liters of cattle feedlot wastewater to measure the nitrogen removal effectiveness and to compare this removal to nitrogen removal models. The 23-tanks were separated into six different treatment series, and the effects of four different total nitrogen (TN) loading rates were investigated with three different series surface areas and detention times. The four TN loading rates were 11.4, 8.0, 2.3, and 0.5 g TN/day. All four loading rates were tested in treatment series consisting of four tanks. Additionally, the 2.3 g TN/day loading rate was tested in a series with two tanks and a series with five tanks. The removal of nitrogen constituents from wastewater is dominated by maximizing the permanent removal processes inherent to the nitrogen cycle. Although the nitrogen cycle is a complex interaction of biological and chemical phenomena, maximizing its inherent removal processes is attainable in the wetland environment. The primary facilitator of this nitrogen removal is the root-zone aeration of the predominantly anaerobic environment surrounding the wetland soil. Given proper amounts of dissolved oxygen, the microbiota of nitrification can oxidize ammonia to nitrate, and denitrification can take place in the anaerobic environment, ultimately removing nitrogen from the wastewater in the form of nitrogen gas. An additional permanent nitrogen removal pathway in wetlands is defined by the plant uptake of ammonia and/or nitrate. However, maximizing this removal pathway requires plant harvesting, which can be costly in the full scale wetland treatment settmg and does not always yield an appreciable amount of nitrogen removal.Item Diversity, distribution, and development of the Odonata of the Southern High Plains of Texas(Texas Tech University, 2009-05) Reece, Bryan A.; McIntyre, Nancy E.; Deslippe, Richard J.; Martin, Clyde F.; Mulligan, Kevin; Strauss, Richard E.The diversity, distribution, and developmental patterns of odonates (dragonflies and damselflies; Insecta: Odonata) were examined in the playa system of the Southern High Plains of Texas from 2003-2008. Comparisons were made in these factors between playas surrounded by the two dominant forms of land use (cropland, grassland). Controlled field and lab experiments were performed to examine the causal relationship between environmental variables and growth, development, and survival of larvae of a focal species. Land-use type did have an influence on certain variables, but not consistently or on all variables. Over one hundred new county records were discovered, indicating how little is known about this system. In addition, the dragonfly holdings at the Museum of Texas Tech University were sorted, identified, and compiled, revealing numerous other new county records.Item Effect of anthropogenic disturbance and landscape structure on body size, demographics, and chaotic dynamics of Southern High Plains amphibians(Texas Tech University, 2002-05) Gray, Matthew JamesAmphibian populations are declining globally. Anthropogenic disturbance of landscapes surrounding wetlands may affect fitness, demographics, and dynamics of amphibian populations. Spatial positioning and relative connectedness of wetlands also may influence population demographics. Thus, I examined the effect of anthropogenic landscape use (cultivation vs. grassland) and structure on postmetamorphic body size (a fitness correlate), demographics, and dynamics of amphibians at 16 playa wetlands on the Southern High Plains (SHP) of Texas during 1999 and 2000. Amphibian populations were monitored using drift fence and pitfall traps, landscape structure was quantified using spatial analysis software, and dynamics were assessed using difference equations. Postmetamorphic body size of all amphibian species and age classes generally was greater at grassland than cropland playas, and in 1999 (i.e., a wetter year) than 2000. Abimdance of New Mexico and plains spadefoots (Spea multiplicata and S. bombifrons) generally was greater at cropland than grassland playas, and greater for barred tiger salamanders (Ambystoma tigrinum mavortium) in 1999 than 2000. Mean daily abundance of amphibians also was positively related to landscape structure indices representing geometric complexity and spatial positioning of wetlands. In general, as landscapes became more complex (e.g., numbers of edges increased) and inter-playa distance decreased, mean daily abundance of amphibians increased. Additional demographic analysis indicated that temporal niche partitioning existed in SHP amphibian populations; however, no differences existed between landuses. Lastly, biological chaos in the amphibian assemblage existed at 1 of 8 cropland and 7 of 8 grassland playas. A stochastic density-dependent Ricker function predicted chaotic dynamics most accurately. Anthropogenic disturbance surrounding wetlands affects body size, demographics, and dynamics of SHP amphibians. Spatial positioning of wetlands and landscape complexity may be as or more important than general landuse in affecting amphibian demographics. Annual differences in body size and abundance suggest rainfall may be important in influencing amphibian populations. Although spadefoot abundance was positively influenced by anthropogenic disturbance, I recommend retention and restoration of grasslands surrounding playa wetlands because landscape cultivation decreased body size and altered amphibian demographics and dynamics from an undisturbed state. These results have important implications in conservation biology, landscape ecology, and basic ecological and mathematical theory.Item Effects of simulated inundation on wetland methane flux predictions for the southeastern U.S.(2015-08) Resovsky, Alex Edward; Yang, Zong-liang; Shanahan, Timothy M; Breecker, Daniel OThis work provides an overview of factors that influence methane emissions from natural wetlands in the southeastern U.S. at seasonal and interannual timescales. It then examines simulations using CLM4Me, a methane biogeochemistry model run within CESM, through comparison with recently compiled flux estimations from remote sensing data. In addition, we assess how seasonal methane flux simulations in CLM4Me are affected by the use of alternative estimates of inundated land fraction. Inundation predictions are provided by DYPTOP, a TOPMODEL implementation which can be used to simulate the dynamics of wetland spatial distribution. Results may aid in future model development and in understanding the role of subtropical and temperate North American wetlands under future climate projections.Item Hydrology of a Forested Wetland Complex in an Urbanizing Area of the Texas Gulf Coast and Clean Water Act Implications(2014-12-15) Dean, Dex DanielSwales in wetland complexes can provide evidence of hydrologic connectivity for wetlands on the Texas Gulf Coast, supporting the idea that many coastal wetlands in Texas are vitally connected to navigable waters covered by the Clean Water Act. In this study, runoff that accounted for more than 18% of rainfall was observed from a representative ?isolated? wetland complex?wetland depressions and upland areas interconnected by shallow erosional features?southeast of Houston, Texas between March 2005 and April 2010. Annual runoff ranged from 0% in 2005 to 27% in 2007. This result was surprising, given the presumably isolated nature of the wetlands. The wetland complex was predominantly forested, with emergent vegetation dominating some of the depressions. Measured hydrologic fluxes included: (1) rainfall, using a tipping-bucket rain gauge supplemented with official weather station data; (2) surface runoff, using a v-notch weir to measure discharge from a wetland swale; (3) transpiration of Quercus nigra (18.0 cm diameter) and Quercus pagodafolia (15.9 cm diameter) using the heat-dissipation sap flux method; (4) groundwater level changes, using piezometers, and (5) soil moisture changes, using soil moisture probes. Watershedscale evapotranspiration was estimated using the Hargreaves model. Surface runoff, although intermittent, occurred during 25 of 57 months. Monthly runoff ranged from 0% of rainfall to 57% of rainfall. Soil moisture loss trended with increased transpiration rates, where the Q. nigra specimen transpired 11.6 to 35.8 L d-1 and Q. pagodafolia specimen transpired 2.43 to 13.8 L d^-1. Moisture was depleted rapidly in the upper soil layer, emphasizing the importance of considering local weather patterns when identifying wetlands and making jurisdictional decisions. The results of this study call into question regulatory presumptions about coastal plains wetlands (at least 400,000 ha in Texas alone), of which roughly 50% are considered geographically isolated. One way to improve implementation of federal rules for wetlands similar to those in this study, which are reasonably close to both navigable and non-navigable streams, is for regulatory agencies to determine whether the wetlands are adjacent to a navigable water before making other decisions that would lead to a presumption that significant nexus does not exist.Item Physical and chemical characteristics of playa soils in southwest Kansas(Texas Tech University, 1996-12) Bauchert, James ANot availableItem Section 404 permitting in coastal Texas from 1996 - 2003: patterns and effects on streamflow(2009-05-15) Highfield, Wesley E.This study explores the spatial-temporal patterns of Section 404 permitting program under the Clean Water Act and examines its impact on mean and peak annual streamflow. The study area consists of 47 sub-basins that are delineated based on USGS streamflow gauges. These sub-basins span from the southern portion of coastal Texas to the easternmost portion of coastal Texas. Descriptive, spatial and spatial-temporal statistical methods are used to explore patterns in Section 404 permitting between 1996 and 2003. The effects of Section 404 permit types on mean and peak annual streamflow over the same 8 year period are also statistically modeled with a host of other relevant control variables. Exploratory analyses of Section 404 permits demonstrated characteristics that were indicative of suburban and, to a larger extent, exurban development. Explanatory analyses of the effects of Section 404 permitting on mean and peak streamflow showed that Section 404 permits increase both measures. These increases were minimal on a per-permit basis but have the ability to accumulate over time and result in much larger increases. Section 404 permits also displayed an ordered effect based on the permit type. Permit types that represent larger impacts had larger effects. The effects of permits of streamflow followed a descending pattern of Individual permits, Letters of Permission, Nationwide permits, and General permits. This ?type of permit impact? supports the use of this measure as an indicator of wetland impact and loss and corroborates previous studies that have incorporated this measure.Item The 2015 Clean Water Rule's impact on oil and gas development in the Bakken Shale(2016-05) Oliver, Mark Moore; Butler, John C. (Clinical associate professor); Kreitler, Charles W.; Fisher, William LThe 2015 Clean Water Rule (CWR) amended the definition of aquatic resources under the federal jurisdiction of the Clean Water Act (CWA). Jurisdiction is re-asserted over a specified portion of aquatic resources legally designated as isolated. The “isolated waters” stipulations apply to the Prairie Pothole Region (PPR), a region recently threatened by heightened oil and gas activity associated with the economic productivity of the underlying Bakken shale. The architects of the CWR claim it does not dramatically expand the jurisdictional scope of the CWA. The Oil and Gas Industry refutes this notion claiming the expansionary nature of the CWR will dramatically increase indirect costs associated with the CWA Section 404 dredge and fill provisions, crippling production in select regions. This study incorporates GIS spatial analysis with predictive modeling tools to determine the CWR’s impact to oil and gas development in the Bakken Shale portion of the PPR. More specifically, this study estimates and characterizes the extent of geographically isolated waters in the study region, determines the scope of jurisdiction within the study region based upon the CWR’s stipulations, and forecasts the economic impact to the oil and gas industry based upon the industry’s development footprint from 2006-2014. Results reaffirm the substantial amount of aquatic resources located within the study region. Furthermore, a significant portion of those resources will become jurisdictional under the new rule. However, the impacts to oil and gas industry are not expected to parallel the increase in jurisdiction. Development patterns over the last decade reveal an insignificant number of permanent impacts to wetlands associated with the development of 4,000 wells. Instead, the estimated increase in jurisdiction will increase the importance of incorporating environmental awareness measures into current operations to alleviate inevitable costs associated with delays, mitigation, and compensation, all while ensuring the industry’s long-term sustainability.Item The Amenity Value of Wetlands(2010-07-14) Gao, ShanWetlands provide recreation and cultural values including scenic views, aesthetics, open-spaces, and leisure opportunities to surrounding residents. This study applies a hedonic approach to estimate the impact of wetland amenities on nearby single family homes using actual sales prices of properties from 1991 to 2005 in Chatham County, Georgia, where wetland resources are unevenly distributed in terms of types and quantities of wetlands. Separate hedonic models are investigated to understand the spatial variation of wetland amenity effects across different study areas in Chatham County. This study finds that wetland amenity values vary mainly with the characteristics of study location. In a rural setting where wetland resources are ample and sufficient. Wetland amenities have negative impacts on the sales price of nearby single family homes. Forested wetlands, the size of the nearest wetland, and wetland proximity negatively impact the sales price of the properties. In an urban setting where wetland resources are extremely limited, wetlands have significant positive amenity effects. The size of the nearest wetland positively impact the sales price of nearby single family homes, but type of wetlands turns into insignificant. In a suburban area with diverse wetland recourses in term of types of wetlands, mixed amenity effects are found. In general immediate access to a wetland, especially a large size one, positively impact nearby single family homes. Type of wetlands plays a key role in deciding the direction and magnitude of wetland amenity effects in a suburban area. The findings of the study suggest that policy makers need to think about both the characteristics of wetlands and their spatial context when providing or protecting wetland amenities.