Latitudinal and Altitudinal Gradients of Riverine Landscapes in Andean Rivers
Date
2022Author
Habit, Evelyn
Zurita, Alejandra
Díaz, Gustavo
Manosalva, Aliro
Arriagada, Pedro
Link, Oscar
Górski, Konrad
Publisher
WaterDescription
Artículo de publicación SCOPUS - WOSMetadata
Show full item recordAbstract
Exact knowledge of the physical structures of different river sections that govern their
ecological structure and function is essential for the efficient conservation and management of
riverine ecosystems. Eleven Andean river basins (Maipo, Rapel, Mataquito, Maule, Itata, Biobío,
Toltén, Valdivia, Bueno and Puelo) comprise large scale latitudinal and altitudinal gradients and
accommodate 71% of the Chilean population that strongly depend on their ecosystem services.
Here, based on 16 hydrogeomorphic variables (on basin, valley and channel scales), we assessed
the riverine landscapes (Functional Process Zones; FPZs) of these river basins using a top-down
multivariate statistical approach. Two steep valley and downstream slope FPZs, three sinuous FPZs
and two braided FPZs emerged in 8906 river sections. The proportion of the occurrence of FPZs
was characterised by a clear latitudinal pattern which is strongly related to the proportions of each
river basin within the large morphostructural units of Chile. As such, the proportion of each river
basin within the Andes Cordillera, Central Valley and Coastal Cordillera is a strong driver of the
fluvial geomorphology and, thus, of the FPZs’ arrangement in each river network. FPZ classification
captured geomorphic diversity that coincided with the latitudinal and altitudinal gradients of Chilean
Andean river basins strongly related to the hydrological characteristics of the assessed river basins and
large scale spatial distribution of fish fauna endemism. As such, the identified large geomorphic units
(FPZs) that are strongly tied up with hydrology and ecology hierarchies of riverine landscape provide
robust operational tools that can be instrumental for river ecosystem monitoring and management at
a basin scale.