Your browser doesn't support javascript.
loading
Downstream effects of hydropower production on aquatic macroinvertebrate assemblages in two rivers in Costa Rica
Chaves-Ulloa, Ramsa; Umaña-Villalobos, Gerardo; Springer, Monika.
  • Chaves-Ulloa, Ramsa; Universidad de Costa Rica. Escuela de Biología. CR
  • Umaña-Villalobos, Gerardo; Universidad de Costa Rica. Escuela de Biología. CR
  • Springer, Monika; Universidad de Costa Rica. Escuela de Biología. CR
Rev. biol. trop ; 62(supl.2): 179-201, abr. 2014. graf, mapas, tab
Article in Spanish | LILACS | ID: lil-753765
ABSTRACT
Despite the fact that little is known about the consequences of hydropower production in tropical areas, many large dams (>15m high) are currently under construction or consideration in the tropics. We researched the effects of large hydroelectric dams on aquatic macroinvertebrate assemblages in two Costa Rican rivers. We measured physicochemical characteristics and sampled aquatic macroinvertebrates from March 2003 to March 2004 in two dammed rivers, Peñas Blancas and San Lorenzo, as well as in the undammed Chachagua River. Sites above and below the dam had differences in their physicochemical variables, with wide variation and extreme values in variables measured below the dam in the San Lorenzo River. Sites below the dams had reduced water discharges, velocities, and depths when compared with sites above the dams, as well as higher temperatures and conductivity. Sites above dams were dominated by collector-gatherer-scrapers and habitat groups dominated by swimmer-clingers, while sites below dams had a more even representation of groups. In contrast, a comparison between two sites at different elevation in the undammed river maintained a similar assemblage composition. Tributaries might facilitate macroinvertebrate recovery above the turbine house, but the assemblage below the turbine house resembled the one below the dam. A massive sediment release event from the dam decreased the abundance per sample and macroinvertebrate taxa below the dam in the Peñas Blancas River. Our study illustrates the effects of hydropower production on neotropical rivers, highlighting the importance of using multiple measures of macroinvertebrate assemblage structure for assessing this type of environmental impact. Rev. Biol. Trop. 62 (Suppl. 2) 179-201. Epub 2014 April 01.
RESUMEN
Existe poca información publicada sobre el efecto de grandes represas hidroeléctricas (>15m alto) en ríos tropicales. Investigamos los efectos de estas represas en las comunidades de macroinvertebrados acuáticos en dos ríos de Costa Rica. Medimos características físico-químicas y recolectamos macroinvertebrados a lo largo del año en dos ríos represados, Peñas Blancas y San Lorenzo, así como en el río Chachagua, el cual no era utilizado para la producción hidroeléctrica. Los sitios arriba y debajo de las represas presentaron diferencias físico-químicas, con amplia variación y valores extremos en las variables medidas debajo de la represa en el Río San Lorenzo. Los sitios arriba de las represas estaban dominados por colectores-recolectores-raspadores y nadadores-colgadores, mientras que debajo de las represas hubo una representación más equitativa de grupos funcionales. En contraste, las comunidades fueron semejantes en dos sitios a diferente elevación en el río sin represa. La presencia de afluentes podría haber facilitado la recuperación de macroinvertebrados arriba de la casa de máquinas, pero las comunidades fueron similares bajo la casa y abajo de la represa. Una liberación masiva de sedimentos disminuyó la abundancia y el número de táxones bajo la represa en el Río Peñas Blancas.
Subject(s)

Full text: Available Index: LILACS (Americas) Main subject: Water Movements / Environmental Monitoring / Geologic Sediments / Invertebrates Limits: Animals Country/Region as subject: Central America / Costa Rica Language: Spanish Journal: Rev. biol. trop Journal subject: Biology / Tropical Medicine Year: 2014 Type: Article Affiliation country: Costa Rica Institution/Affiliation country: Universidad de Costa Rica/CR

Similar

MEDLINE

...
LILACS

LIS

Full text: Available Index: LILACS (Americas) Main subject: Water Movements / Environmental Monitoring / Geologic Sediments / Invertebrates Limits: Animals Country/Region as subject: Central America / Costa Rica Language: Spanish Journal: Rev. biol. trop Journal subject: Biology / Tropical Medicine Year: 2014 Type: Article Affiliation country: Costa Rica Institution/Affiliation country: Universidad de Costa Rica/CR