Soil-bioengineering measures for river bank protection of the Rio Guarda Mor (South Brazil)
Abstract
Bioengineering measures for bank protection along rivers and creeks are commonly used in Europe and North America, since they offer long-term stability, they can be erected using renewable material and - provided a proper construction and maintenance - can be of ecological value as well. To implement these environmentally friendly and resource sparing techniques to Brazil, appropriate tree species' have to be selected and investigated and various bio-engineering methods must be adapted to the local climate and working conditions. To this end selected species' are being tested in regard to their capability to develop adventitious roots and shoots. Moreover different bioengineering constructions will be erected and monitored in situ focussing on their performance under different regional and local conditions. The watershed of Rio Guarda Mor, i.e. the river investigated in this project, is located near the university city of Santa Maria, in the centre of the southernmost Brazilian province of Rio Grande do Sul. The lower course of the river extends from at an altitude of 100 m to 40 m a.s.l. This stretch is characterized by intense agriculture, mostly paddy fields, that reach to the very edge of the bank of Rio Guarda Mor. Planned measures: 1) Bio-engineering testing mound: The investigation of the suitability of autochthon plants for soil bio-engineering purposes is regarded as basis for the utilization of plants and parts of plants for protection measures. This investigation is realized by means of a bio-engineering testing mound, i.e. a proved methodology developed by the department of soil bio-engineering and landscape construction. Plants to be tested are implemented into the mound like brush layers and the development of adventitious roots is observed in predefined intervals. Further steps include the following bio-engineering constructions, which will be erected exemplarily along the banks of Rio Guarda Mor: 2) Planted Crib Wall: This massive technique, which is expensive in human labour as well as in material, is highly appropriate to protect steep banks, to secure bridge-heads and fords but also to stabilize the foot of other constructions. This type will be built at an exposed undercut-slope bank of Rio Guarda Mor. 3) Brush Mattress: The brush mattress is recognized as the bio-engineering technique that resists the highest hydraulic loads. The functional range of brush mattresses is universal, it is mainly apt to protect eroding banks and other steep acclivities exposed to high hydraulic drag forces. This bio-engineering type will be erected on a bank upstream of a ford at Guarda Mor river. Coarse blocks will serve as a toe protection. To provide and ensure the transfer of knowledge and the monitoring of the performance four grad students of the BOKU University will stay in the project area for several months, both Project Leader and Project Manager will visit the site and a PhD student of Universitade Federal Santa Maria (UFSM) will realize his thesis at the BOKU university in Vienna supervised by the Project Leader
botany erosion (erosion control) plant sociology Brazil Riverbank protection
Publikationen
Project staff
Florin Florineth
Em.O.Univ.Prof. Dr.phil. Florin Florineth
florin.florineth@boku.ac.at
Project Leader
01.07.2003 - 31.12.2006
Stephan Vollsinger
Dipl.-Ing. Stephan Vollsinger
s.vollsinger@boku.ac.at
Project Staff
01.07.2003 - 31.12.2006
BOKU partners
External partners
University of Santa Maria, Department of Forest Sciences
Prof. Dr. Miguel Antao DURLO, MSc. Fabricio SUTILI
partner