Tropical Ecology and Conservation [Monteverde Institute]

Alternative Title

La continuidad del río San Luis: Una mirada a los cambios químicos y biológicos a lo largo de un gradiente longitudinal del río


Kit Hamley



Download Full Text (243 KB)

Publication Date

May 2009


From start to finish, physical changes along a river continuum create a natural longitudinal gradient to which biotic communities respond. This biotic response to natural physical change is a fundamental pattern of river ecology and is generally called The River Continuum Concept. The purpose of this study was to look at changes in water quality and aquatic insect communities along a pristine river continuum. Data was collected along a 1-kilometer series of 11 sites along the San Luis River in San Luis, Costa Rica. As expected, water quality did not change along the 1-kilometer reach. Overall percent abundances of insect Orders were different for each site. Three regions were created within the 1-kilometer continuum based on similarities in Shannon-Weiner values. Comparisons of these regions showed that percent composition of insect Orders fluctuate between the three regions. Water quality values were consistent over the entire continuum, therefore changes in biotic assemblages due to water degradation can be ruled out. This means that the changes observed in biotic assemblages were due to changes created by a natural longitudinal gradient.


De principio a fin, cambios físicos a lo largo de un rio continuo crea un gradiente longitudinal al cual las comunidades abióticas responden. Estos cambios bióticos son respuestas naturales a los cambios físicos y fundamentales para la ecología del rio y que generalmente se llama Concepto de Continuidad Riparia. El propósito de este estudio fue observar los cambios en la calidad del agua y las comunidades de insectos acuáticos a lo largo de un rio.


River continuum concept, Aquatic insects, CIEE Spring 2009

Palabras claves

Concepto del rio continuo, Insectos acuáticos, CIEE Primavera 2009


8 pages

Geographic Location

San Luis (Puntarenas, Costa Rica)

Holding Location

Monteverde Institute


English; Spanish

Media Type



Digital Only





The San Luis river continuum: a look at the chemical and biological changes along a longitudinal pristine river gradient



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