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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2005.03.014 Byline: K.J. Lim (a), B.A. Engel (a), Z. Tang (a), S. Muthukrishnan (b), J. Choi (c), K. Kim (c) Abstract: Urbanization can result in alteration of a watershed's hydrologic response and water quality. To simulate hydrologic and water quality impacts of land use changes, the Long-Term Hydrologic Impact Assessment (L-THIA) system has been used. The L-THIA system estimates pollutant loading based on direct runoff quantity and land use based pollutant coefficients. The accurate estimation of direct runoff is important in assessing water quality impacts of land use changes. An automated program was developed to calibrate the L-THIA model using the millions of curve number (CN) combinations associated with land uses and hydrologic soil groups. L-THIA calibration for the Little Eagle Creek (LEC) watershed near Indianapolis, Indiana was performed using land use data for 1991 and daily rainfall data for six months of 1991 (January 1-June 30) to minimize errors associated with use of different temporal land use data and rainfall data. For the calibration period, the Nash-Sutcliffe coefficient was 0.60 for estimated and observed direct runoff. The calibrated CN values were used for validation of the model for the same year (July 1-December 31), and the Nash-Sutcliffe coefficient was 0.60 for estimated and observed direct runoff. The Nash-Sutcliffe coefficient was 0.52 for January 1, 1991 to December 31, 1991 using uncalibrated CN values. As shown in this study, the use of better input parameters for the L-THIA model can improve accuracy. The effects on direct runoff and pollutant estimation of the calibrated CN values in the L-THIA model were investigated for the LEC. Following calibration, the estimated average annual direct runoff for the LEC watershed increased by 34%, total nitrogen by 24%, total phosphorus by 22%, and total lead by 43%. This study demonstrates that the L-THIA model should be calibrated and validated prior to application in a particular watershed to more accurately assess the effects of land use changes on hydrology and water quality. Author Affiliation: (a) Department of Agricultural and Biological Engineering, Purdue University, 225 South University Street, West Lafayette, IN 47907-2093, USA (b) Department of Earth and Environmental Sciences, Furman University, Greenville, SC 29613, USA (c) Department of Agricultural Engineering, Kangwon National University, Chuncheon, Kangwon, South Korea Article History: Received 6 August 2004; Revised 16 March 2005; Accepted 18 March 2005

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2005.01.006 Byline: Z. Tang (a), B.A. Engel (a), B.C. Pijanowski (b), K.J. Lim (a) Abstract: Urban expansion is a major driving force altering local and regional hydrology and increasing non-point source (NPS) pollution. To explore these environmental consequences of urbanization, land use change was forecast, and long-term runoff and NPS pollution were assessed in the Muskegon River watershed, located on the eastern coast of Lake Michigan. A land use change model, LTM, and a web-based environmental impact model, L-THIA, were used in this study. The outcomes indicated the watershed would likely be subjected to impacts from urbanization on runoff and some types of NPS pollution. Urbanization will slightly or considerably increase runoff volume, depending on the development rate, slightly increase nutrient losses in runoff, but significantly increase losses of oil and grease and certain heavy metals in runoff. The spatial variation of urbanization and its impact were also evaluated at the subwatershed scale and showed subwatersheds along the coast of the lake and close to cities would have runoff and nitrogen impact. The results of this study have significant implications for urban planning and decision making in an effort to protect and remediate water and habitat quality of Muskegon Lake, which is one of Lake Michigan's Areas of Concern (AOC), and the techniques described here can be used in other areas. Author Affiliation: (a) Department of Agricultural and Biological Engineering, Purdue University, 225 South University Street, West Lafayette, IN 47907-2093, USA (b) Department of Forestry and Natural Resources, Purdue University, 195 Marsteller Street, West Lafayette, IN 47907-2093, USA

An attempt is made to forecast and assess the impact of the predicted land use changes on long-term runoff and non-point source (NPS) pollution in the Muskegon River watershed, using an environmental impact analysis model. The implications of the results for decision-making and long-term urban planning are discussed.

Abstract: Paraelectric PLT(lead lanthanium titanate) thin films were prepared by dc magnetron sputtering with multi element metal target. In order to crystallize the as-deposited PLT thin films to the cubic perovskite phase, post-heat treatment was applied at the temperatures from 450 to 750°C. The composition of PLT(28) thin film was: Pb, 0.72; La, 0.28; Ti, 0.88; O, 2.9. The dielectric characteristics were essentially dependent on the changes in the chemical composition and crystalline phase with variation of annealing treatment. The dielectric constant increased and dissipation factor decreased slightly, as the post-annealing temperature increased. The dielectric constant and dissipation factor at low electric field measurement of the capacitors with highest dielectric properties were 1216 and 0.018, respectively. [Copyright &y& Elsevier]