Journal
GEOMORPHOLOGY
Volume 113, Issue 3-4, Pages 239-252Publisher
ELSEVIER
DOI: 10.1016/j.geomorph.2009.03.014
Keywords
Araguaia River; Deforestation; Tropical; South America; Large rivers; Geomorphologic response
Funding
- CNPq-Brazil
- CYTED Network XII-K
- Vitae Foundation
- Bi-national Project
- PROSUL Program-CNPq-Brazil
- NASA-USA
- Earth Science Enterprises [2700-0087]
Ask authors/readers for more resources
The geomorphic response of the Araguaia River to catastrophic deforestation of the Cerrado since 1970s is discussed. With a mean annual discharge of 6500 m(3)/s and a drainage area of similar to 380,000 km(2), the Araguaia River is the main system draining the savannas of Central Brazil. Here, we demonstrate that the river is undergoing a substantive increase in bed load transport and changes in its geomorphology. A multi-approach methodology was used and involved detailed geomorphologic mapping for three decades (60, 70, and 90), a budget of erosional and deposition areas using GIS, volumetric calculations, and estimations of bed load transport. Our results show that the alluvial plain is undergoing active sedimentation and 233 Mt of sediments were stored by channel activity in a reach 570 km long of the middle Araguaia. The bed load transport has increased 31% from 6.6 Mt in the sixties to 8.8 Mt in the 1990s and the channel pattern has been metamorphosed to some extent. This is an outstanding current example of short term geomorphic response to deforestation in a large pristine tropical fluvial system without direct human interventions in the channel. (C) 2009 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available