Show simple item record

dc.contributor.advisorSotomayor-Ramírez, David
dc.contributor.authorRodríguez-Rivera, Paloma
dc.description.abstractThe eastern part of the Lajas Valley basin has an area of 14,519 ha, a population of about 33,000, and the predominant land use is 9.3% urban or sub-urban, 30% agricultural, and 61% forest / fallow. Quebrada Mondongo and Quebrada Bárbara are two sub-basins with predominant urban and agricultural land use, respectively. Quebrada Mondongo receives processed waters from a secondary sewage treatment plant (WWTP) and WTP and Quebrada Bárbara receives water from a WTP. Previous studies showed that the nutrient levels of streams in these sub-basins had concentrations of total nitrogen (TN) and total phosphorus (TP) in what is considered "enriched" and “impacted”. Assays of benthic metabolism were performed for net primary productivity (NPP) and respiration (R) using in situ recirculating metabolism chambers, and gross primary production (GPP) was computed as GPP = NPP- [-R]. Periphyton biomass, nutrient levels, physical and chemical parameter were also compared between sub-basins and among different points within the sub-basin. Differences between sub-basins were observed and the Quebrada Mondongo had significantly higher periphyton biomass, temperature, DO, specific conductance, flow, pH, TN, dissolved nitrate, TP, and dissolved phosphorus. NPP and R tended to be higher in Quebrada Mondongo, though not significantly. Quebrada Mondongo and the upstream of Quebrada Bárbara had GPP/R <1, suggesting that these benthic ecosystems are predominantly heterotrophic. The WWTP had no apparent effect in the stream ecology, as metabolism rates did not vary significantly from upstream to downstream stations. All sites were classified as either “enriched” or “impacted”, but the urban stream was greatly degraded.en_US
dc.description.abstractLa parte este de la cuenca del Valle de Lajas tiene un área de 14,519 ha, una población de aproximadamente 33,000, y el uso predominante de la tierra es 9.3% urbano o suburbano, 30% agrícola y 61% bosque / barbecho. Quebrada Mondongo y Quebrada Bárbara son dos sub-cuencas con uso predominante de tierras urbanas y agrícolas, respectivamente. Quebrada Mondongo recibe aguas tratadas de una planta secundaria de tratamiento de aguas residuales (WWTP) y una planta de filtros y Quebrada Bárbara recibe agua de una planta de filtros. Estudios previos mostraron que los niveles de nutrientes de estas sub-cuencas tenían concentraciones de nitrógeno total (TN) y fósforo total (TP) en lo que se considera "enriquecido" e "impactado". Los ensayos de metabolismo béntico se realizaron para estimar la productividad primaria neta (NPP) y la respiración (R) utilizando cámaras de metabolismo de recirculación in situ, y la producción primaria bruta (GPP) se calculó como GPP= NPP- [-R]. La biomasa de perifitón, los niveles de nutrientes, los parámetros físicos y químicos también se compararon entre sub-cuencas y entre diferentes puntos dentro de la subcuenca. Se observaron diferencias entre sub-cuencas y la Quebrada Mondongo tuvo mayor biomasa perifitón, temperatura, oxígeno disuelto, conductancia específica, flujo, pH, TN, nitrato, TP y fósforo disuelto. NPP y R tienden a ser mayores en la Quebrada Mondogno, aunque no fue significativo. Quebrada Mondongo y aguas arriba de Quebrada Bárbara tenían GPP/R <1, lo que sugiere que estos ecosistemas bénticos son predominantemente heterótrofos. La WWTP no tuvo un efecto aparente en la ecología de la Quebrada Mondongo, ya que las tasas de metabolismo no variaron significativamente de las estaciones aguas arriba a las aguas abajo. Todas las estaciones se clasificaron como "enriquecidos" o "impactados", pero el flujo urbano se vio como el más degradado.en_US
dc.description.sponsorshipPartially funded by US Environmental Protection Agency (USEPA) Cooperative Agreement no. 83553801 with the University of Puerto Rico Mayagüez Campus.en_US
dc.subjectMetabolism, Water quality, Lajas Valley, WWTP, Land Useen_US
dc.subject.lcshPeriphyton -- Effect of water pollution onen_US
dc.subject.lcshHeterotrophic bacteriaen_US
dc.subject.lcshBiotic communities --Puerto Rico -- Lajas Vallleyen_US
dc.subject.lcshBenthos -- Metabolismen_US
dc.subject.lcshLand use -- Puerto Rico -- Lajasen_US
dc.titleMetabolism and trophic status of streams draining basins with different land use in Southwest Puerto Ricoen_US
dc.rights.licenseAll rights reserveden_US
dc.rights.holder(c) 2018 Paloma Rodríguez-Riveraen_US
dc.contributor.committeeMartínez-Rodríguez, Gustavo
dc.contributor.committeeSantos-Flores, Carlos
dc.contributor.representativeCarrero, Katherine Sciencesen_US
dc.contributor.collegeCollege of Agricultural Sciencesen_US
dc.contributor.departmentDepartment of Crops and Agro-Environmental Sciencesen_US

Files in this item


This item appears in the following Collection(s)

  • Theses & Dissertations
    Items included under this collection are theses, dissertations, and project reports submitted as a requirement for completing a graduate degree at UPR-Mayagüez.

Show simple item record

All rights reserved
Except where otherwise noted, this item's license is described as All Rights Reserved