published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

Development and population are rapidly increasing in urbanizing areas of North Texas and so is the need to understand changes in storm water runoff flow and its contamination by nutrients, sediment, pesticides and other toxicants. This study contributes to this understanding and has two primary components: first, development of a graphical user interface for a geographic information system and storm water management database, and second, performing a two-scale hydrological modeling approach (the US Corp of Engineers HEC-HMS model and the US Environmental Protection Agency SWMM model). Both primary components are used together as a toolkit to support the storm water management program of the City of Carrollton, located in North Texas. By focusing limited city resources, the toolkit helps storm water managers in the process of compliance with federal regulations, especially the National Pollution Discharge Elimination System permit, and provides guidance for reporting, planning and investigation. A planning example was conducted by modeling potential changes in storm water quality due to projections of land use based on the City of Carrollton's Comprehensive Plan. An additional component of this study is the evaluation of future changes in surface water quantity and quality in the North Central Texas area, specifically in a rural but rapidly urbanizing subbasin area of the greater Lake Lewisville watershed. This was accomplished using the US Corp of Engineers HEC-HMS hydrological model. Precipitation scenarios were derived from years of historically high, medium, and low annual precipitation. Development scenarios were derived from current land use in the Lake Lewisville sub basin, current land use in the city of Carrollton, and from Markov projections based on recent land use change calculated from satellite images of 1988 and 1999. This information is useful for future land use planning and management of water resources in North Texas.

This research examines tensions between Latino/a farmworkers, who rely on the seasonal harvest of saw palmetto (Serenoa repens [W. Bartram] Small) berries for increased livelihood security, and conservationists and land-managers who view harvesting as detrimental for wildlife. Informal harvesting occurs on public and private lands, sometimes without permission. Berries, though ubiquitous on the landscape, have become a contested resource. The rapid conversion of rural wildlife habitat into suburban development has increased State urgency to bring natural areas into protection along the Florida Ecological Greenways Network. Habitat infringement and associated pressures on wildlife by development has led to the promotion of the state-wide Florida Wildlife Corridor, based on the FEGN. This corridor would connect isolated Florida black bear (Ursus americanus floridanus) populations and Florida panthers (Puma concolor coryi) with other populations. The scale of the commercial berry industry is unknown, but is estimated at millions of pounds annually. State and wildlife conservationists are increasingly concerned with the perceived scale of the harvest and its possible associated effects on wildlife, particularly Florida black bears. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

abstract / toc / Geography and Geology / Doctoral / Doctor of Philosophy

published_or_final_version / Urban Design / Master / Master of Urban Design

Little is known regarding the effects of land use on soil organic matter and P status of South African soils. For that reason, the effects of the main agricultural land uses in the midlands region of KwaZulu-Natal [maize (Zea mays), sugarcane (Saccharum spp), annual ryegrass pasture (Lolium multiflorum), permanent kikuyu pasture (Pennisetum clandestnum), gum (Eucalyptus grandis) and pine (Pinus patula)] on soil organic matter content, microbial biomass C and P and inorganic and organic P pools derived from a modified Hedley P fractionation was investigated on two sites where the longterm history of land management was known. In comparison with undisturbed native grassland, permanent kikuyu pasture resulted in an increase in organic C, organic P and microbial biomass C and P. Maize and sugarcane production resulted in a decrease in organic C, organic P and microbial C and P. Under annual pasture, gum and pine forests, organic matter and microbial biomass concentrations remained similar to those under native grassland. Under native grassland, extractable organic P accounted for 50% or more of the total P content of soils but under agricultural management with regular applications of fertilizer P, there was an increase in the percentage of total P present as inorganic P. Agricultural management greatly affected the distribution of P among the various inorganic and organic P fractions. Resin-Pi and NaHC03-Pi (the potentially-available forms of Pi) showed similar trends with land use being greatly elevated under kikuyu pasture at both sites and sugarcane and maize at one site. This accumulated Pi was thought to have originated from recent fertilizer applications and possibly recently mineralized organic P. Trends for NaOH-Pi with land use differed greatly from those of the Resin- and NaHC03Pi fractions. Concentrations were notably high under maize and sugarcane production. Of the pools of soil organic P, the NaHC03-Po fraction was most greatly affected by land use, being elevated under kikuyu and decreased under maize and sugarcane. This supports the assertion that it is the NaHC03-Po fraction that is the most labile soil organic P pool. It was concluded that land use greatly affects soil organic C and P status, soil microbial biomass C and P contents, soil inorganic P concentrations and the distribution of P among the various P fractions. A short-term (8 weeks) laboratory incubation experiment was carried out to compare the effects of inorganic (KH2P04) and organic (cattle manure, poultry manure and maize crop residues) sources of P, applied at a rate equivalent to 30 kg P ha-1 , on soil inorganic and organic P fractions and the potential availability of soil P. Additional treatments consisted of lime [Ca(OHhl at 5 ton ha-1 and lime plus inorganic P. Applications of lime raised soil pH to a similar extent after 1, 4 and 8 weeks incubation. After 8 weeks, a small increase in soil pH was also noted for the cattle and poultry manure and maize residue treatments. For the inorganic P fractions, substantial treatment effects were observed only for the Resin-Pi fraction. The inorganic P source was more effective than the organic ones at increasing Resin-Pi after 1 and 4 weeks incubation and of the organic sources, cattle and poultry manure were more effective than maize residues. Resin-Pi concentrations generally increased between 1 and 4 weeks incubation but then declined rapidly between 4 and 8 weeks incubation. After 8 weeks incubation, treatment effects on Resin-Pi were small. Concentrations of NaHC03-Pi, dilute HCI-Pi and concentrated HCI-Pi all declined over the incubation period. There was no clear trend with incubation for NaOH-Pi although for the poultry manure and maize treatments, concentrations declined between 4 and 8 weeks incubation. In general, concentrations of NaHC03-Po were greater for organic than inorganic P sources after 8 weeks incubation suggesting microbial immobilization of P in these treatments. There were increases in NaHC03-Po and concentrated HCI-Po over the incubation period suggesting progressive immobilization of P from the Pi fractions that declined in concentration during the incubation. Concentrations of NaOH-Po were not greatly affected by incubation period. The lime treatments, however, had lower NaOH-Po concentrations than the others suggesting that liming may have stimulated microbial mineralization of Po. Residual-P concentrations increased over the incubation period. This was attributed to conversion of extractable Pi fractions into recalcitrant, non-extractable Pi forms and/or immobilization of Pinto intransigent organic forms. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

This thesis seeks to explain how site-scale design decisions can assist retention of rare plant communities concentrated in and near settled areas. To do so it focuses on a specific species and development context. Explanations are sought through examination of case studies of landuse developments in proximity to retained Garry oak plant communities located in the perimeter of Victoria, British Columbia. In the study region, exponential declines in species populations, health, and diversity of rare Garry oak ecosystems have been largely attributed to impacts from land-use developments. Over the past century, land-use developments have transformed the floral, spatial, structural and functional characteristics of the settled landscape. Isolated islands of imperiled plant associations remain on protected bioreserves: for recruitment and connectivity, these rare fauna rely on private-land greenways. Architectural teams have the potential to influence the decision-making processes that create ecologically-vital greenspace on private land, thereby enhancing survival for declining plant communities. Case-study evidence for the importance of land-use decisions on diminishing Garry oak meadow is gathered through vegetation surveys conducted on Garry oak meadow in proximity to six architectural projects on Victoria's western edge. Observed changes in growth extensions are then categorized in relation to human activities associated with built form, and correlated with principles from Landscape Ecology. An ARC of design strategies, developed in primary research by K. D. Rothley is adapted for architectural use as follows: firstly, AREA of a plant community is kept free of encroachment by the orderly frame established around vegetation; secondly, RARE SPECIES and habitat are identified with borders or signage; thirdly, CONNECTIVITY between retained landscapes is secured by siting roads and buildings to minimize ecosystem fragmentation. To effectively communicate preexisting landscape ecology principles, grouped under the ARC of strategies, illustrations and key-word phrases are developed. These principles, when integrated into architectural teams' structural knowledge, extend the architects' perceived role beyond aesthetics and economic efficiency. Enhancing habitat value through retention or restoration of rare ecosystems at the margins of suburban development, becomes an additional realm of influence for professional teams designing the spatial configurations of peri-urban landscapes.

The Albert Falls Area had witnessed severe competition over land use between agriculture, recreation, conservation and other land uses. The area also has been the scene for inefficient land management that led to degradation of land resources. For proper land use planning and environmental management, information on land use/cover change is vital. This study has developed a spatial and descriptive historical land use/cover databases for the years 1944, 1967, 1989, and 2000 to provide an understanding of land use/cover patterns in Albert Falls Area. The databases were created by interpreting historical aerial photographs and using Geographic Information Systems. The data was subsequently analyzed to detect relevant trends in land use/cover patterns in the study area. Generally land use/cover pattern of Albert Falls Area during the period 1944 to 2000 may be described as being mainly agricultural. The results showed a marginal increase of indigenous forests attributed to the continuous efforts by different governmental departments and policies that focused on the protection of the remaining patches of indigenous forests. Grassland not only decreased by more than half but it also deteriorated in quality during 1944 to 2000. Commercial Forestry predominates the study area and showed an increasing trend from 1944 to 1967. Cultivated Land was observed to decrease at the expense of Commercial Forestry plantations and Waterbodies. Although sugarcane plantations increased after 1967, total Cultivated Land showed a decreasing trend. The construction of Albert Falls Dam and other small Farm Ponds within the agricultural farms increased the land areas covered by Waterbodies. Residential Area coverage generally decreased irrespective of the encroachment of informal settlements, while that outside Non-Residential Area and Transportation Routes generally increased with the development of commercial agriculture in the area. Barren Land decreased continuously due to higher land demand in the study area. The study showed that land use/cover changes in Albert Falls Area. have resulted in habitat fragmentation, development of monoculture land use, flourishing of Farm Ponds in agricultural farms, and expansion of agricultural activities on marginal lands. Creation of corridors/linkages between the fragmented forest patches; commencement and implementation of the already well drafted land and land resource policies and regulations; commencement of the holistic management plans in the area were recommended for a sustainable land use. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.

This research explores decision making in land suitability with regard to natural resource management, as it is practised in South Africa and internationally. The complexity of the problem leads to the need to use stakeholder analysis and Multi-Criteria Decision Analysis which are researched further in the dissertation. A framework for decision making on land suitability is suggested. It is applied experimentally in several case studies on decision making in land suitability with regard to natural resource management. A land suitability analysis provides a typical scenario whereby a hard factual approach such as a GIS with data on soils, climate, rainfall, topography, ecosystems, etc. is combined with socio-economic activities such as agriculture, forestry and nature conservation. Most land suitability analysis is carried out with the aid ofa GIS. However, a GIS is limited to largely objective, spatial data. It is here that multicriteria decision analysis plays an important role by combining the different stakeholder perspectives with socio-economic and scientific data in a comprehensive Decision Support System. In this research, the Analytic Hierarchy Process is used to produce an experimental model on decision making in land suitability and this model is then tested against real life case studies which proves the model to be a valid decision making technique. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.

Nature provides essential services to humans, including climate regulation, water provisioning and regulation. These so-called ecosystem services have economical, societal and environmental value. This research aims at improving the knowledge on the linkages between selected hydrological ecosystem services and current and proposed land uses within the water-limited Mpushini/Mkhondeni Catchments in South Africa. The research contributes to the recognition of feedback and linkages within the complex ecological-human system, so that informed land use decisions can be made. The research aim is achieved by first reviewing the literature on hydrological ecosystem services, land use in an ecosystem services context and the links between the two. The study area is then sub-delineated into land use determined hydrological response units for baseline natural land cover, as well as for current and proposed land use scenarios. Using an appropriate model, selected hydrological processes are simulated in order to isolate the effects of individual land uses on hydrological responses, both on a local and a more catchment-wide scale. Various land uses were found to affect hydrological responses, such as runoff and its components of stormflows and baseflows, as well as transpiration and sediment yields, differently. These responses were found to be suitable indicators of selected ecosystem services such as water provisioning or flow regulation. Irrigation and high biomass crops, such as sugarcane and wattle plantations were found to reduce downstream water provisioning services. Degraded lands were found to reduce physical water quality through increased sediment yield, to reduce water provisioning during low flow periods, while the degraded lands increased stormflows, thereby reducing regulation of high flows. Urban land uses were found to significantly increase runoff, with increased impervious areas causing a shift from evaporation and transpiration towards runoff. Stormflows increased, with high flow regulation being reduced. Baseflows increased as well, as a result of a spill-over of runoff from impervious to pervious urban areas, which led to increased low flow regulation. In addition, in this study area urban return flows are generated from externally sourced water, further increasing streamflows and especially low flows. While urban areas showed an increase in downstream water quantity provision, the water quality was reduced. The combined effects of the current land use mosaic on the annual streamflows partially cancel each other out, while the proposed urbanisation dominated hydrological responses. Influences of various land uses on hydrological ecosystem services were thereby shown, which contributes to a better understanding of the linkages between the two. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2014.