Land-use effects on structural and functional composition of benthic and leaf-associated macroinvertebrates in four Andean streams

Abstract

The replacement of native forests by pastures takes place widely in the Andes. The effects of such land-use change on aquatic assemblages are poorly understood. We conducted a comparative analysis of the effects of forest conversion to pastures on the taxonomic, structural, and functional composition of macroinvertebrates (benthic and leaf-associated) in montane and upper montane streams (ecosystem type) of the south Ecuadorian Andes. Taxonomic composition of benthic and leaf-associated macroinvertebrates was different between ecosystem type and land use. Also, major differences in the structural and functional composition of benthic and leaf-associated macroinvertebrates were mainly promoted by land use in both ecosystem types. Forested streams showed higher diversity than pasture streams, sustaining more shredder, scraper, and predatory invertebrates. We also observed differences in the macroinvertebrate communities between benthic and leaf-bag samples. Leaf bags had lower diversity and more collector invertebrates than benthic samples. This study highlights the large effect of riparian forest conversion to pasture land on macroinvertebrate communities, and the importance of using appropriate sampling techniques to characterize aquatic assemblages. We also recommend the maintenance and restoration of riparian vegetation to mitigate the effects of deforestation on stream communities and ecosystem processes.

Lichen Responses to Disturbance: Clues for Biomonitoring Land-use Effects on Riparian Andean Ecosystems

“…This research is the first in Ecuador to quantify the response of taxonomic diversity and functional traits of epiphytic lichens to different land-use intensities along the riparian ecosystems of southern Andean streams. This area is affected by rapid forest transformation [9,35] and its riparian zones present a high degree of alteration [12,36,37]. Furthermore, we demonstrate, as in other regions (e.g., [20]), the complementary application of lichen's taxonomic and functional traits to detect and monitor changes in the structure and functioning of tropical Andean ecosystems.…”

“…Most of the tropical primary forests (e.g., montane Andean forests) were transformed to secondary forests, pastures, cropland, and urbanized areas to satisfy human needs [2,6,9]. In consequence, the diversity of plants, lichens, birds, arthropods, fish, reptiles and mammals has been diminished because of land use [4,[10][11][12].…”

Diversidad de macroinvertebrados acuáticos en quebradas con diferente cobertura ribereña en del bosque Protector Murocomba, cantón Valencia, Ecuador

“…Giraldo, Chará, Zúñiga, Chará-Serna & Pedraza, 2014;Galeano-Rendón, Monsalve-Cortes, & Mancera-Rodríguez, 2017), disminuyendo el material alóctono que ingresa al cuerpo hídrico y la disponibilidad de sustratos aportados por los bosques adyacentes (e.g. Bücker, Sondermann, Frede, & Breuer, 2010;Giraldo et al, 2014), y alterando la estructura y la función trófica de las comunidades de insectos acuáticos (e.g., Lorion & Kennedy, 2009;Ferrú & Fierro, 2015;Iñiguez-Armijos, Hampel, & Breuer, 2018).…”

“…Diversos estudios han encontrado que los cambios en el uso de la tierra y por consiguiente en las coberturas vegetales de los márgenes de las quebradas, tienen efectos sobre los ensamblajes de macroinvertebrados acuáticos, con variaciones en la composición taxonómica y de grupos funcionales y una disminución de la diversidad en quebradas con coberturas de bosques nativos, con relación a quebradas con coberturas de plantaciones de bosques exóticos, y de pastos para actividades agrícolas y ganaderas (e.g. Lorion & Kennedy, 2009;Fierro et al, 2017;Iñiguez-Armijos et al, 2018).…”

“…Giacometti & Bersosa, 2006;Arroyo & Encalada, 2009;Terneus, Hernández, & Racines, 2012;Álvarez-Mieles et al, 2013;Villamarín, Rieradevall, Paul, Barbour, & Prat, 2013;Damanik-Ambarita et al, 2016;Liñero et al, 2016), sobre la diversidad taxonómica y funcional en relación con los regímenes de caudal y disturbios hidrológicos o como respuesta a factores ambientales y condiciones fisicoquímicas (e.g., Jacobsen & Encalada, 1998;Carrera & Gunkel, 2003;Ríos-Touma, Encalada, & Prat, 2009, 2011, existiendo poca información acerca de los efectos de los cambios de la vegetación riparia sobre las comunidades de macroinvertebrados acuáticos (e.g. ; Bojsen & Jacobsen, 2003;Bücker et al, 2010;Iñiguez-Armijos, Leiva, Frede, Hampel & Breuer, 2014;Iñiguez-Armijos et al, 2016;Iñiguez-Armijos et al, 2018).…”