Navigation Links
Impact of eucalyptus plantations on the ecology of rivers
Date:1/14/2010

For more than twenty years this team has been trying to identify links between the ecology and functioning of rivers and the surrounding terrestrial environment because, when all is said and done, rivers are like the excretory apparatus of the continents, just like the kidney is to the human body. River water often reflect the state of health of the external environment.

Within this line of research, the UPV/EHU team is focusing on studying the possible impact of the afforestation of exotic species on the functioning of rivers, both on the chemistry of the water as well as on the communities of organisms therein. An exotic species is a species introduced outside its normal area of distribution, for example, the eucalyptus the case in hand.

Rivers of any specific geographical environment have a natural riverside type of vegetation and the community of organisms in the river is accustomed to consuming the dead leaves and foliage that enter the water from this surrounding vegetation. When this natural vegetation (in this case deciduous woods) are substituted by exotic plantations the quality of this plant material changes and the community of river organisms have to deal with the use or otherwise of this non-autochthonous organic material. This use or not by the aquatic organisms of the new material entering the river system can have certain repercussions, both on the organisms themselves and on processes occurring in the river.

Until recently the methods on which the diagnosis of masses of water were based were structural ones, i.e. the study, for example, of the presence or otherwise of certain organisms were taken as indicators of better or worse quality of a river. Recently, however, attempts are being made to take into account not only the structure, i.e. the organisms that are there and not there, but also what the organisms that exist do, that is, if the river processes function in a suitable manner. In relation to the tendency that exists of examining the processes when evaluating the ecological state of the rivers, the team at the UPV/EHU focused principally on the decomposition of dead leaves and foliage. Their goal was to evaluate the ecological state of the river water based on the response of a process, in this case the decomposition of the dead leaves, to various kinds of impact.

Eucalyptus vs deciduous species

Dead leaves are the source of energy in the streams that drain forest river basins. The researchers at the Department of Plant Biology and Ecology at the UPV/EHU undertook studies of the dead vegetation from the eucalyptus. The eucalyptus is a species that loses more leaves in the summer; in other words, most of the energy that can enter the river ecosystem from a eucalyptus plantation does so at this time of the year. It coincides with the period when the rivers are at their lowest level and, as a result, a large amount of this material stays in the rivers. Theoretically the organisms would have a greater amount of material to consume. Nevertheless, certain studies have shown that the dead vegetation from eucalyptus has a number of toxic products (polyphenols) that can have negative effects on the development of some organisms. In any case the dead leaves rapidly lose these toxic compounds once in the water and so, according to the studies carried out, after the passing of a certain period of time, the eucalyptus material decomposes and used in the same manner as other material.

The UPV/EHU team also evaluated the quantity of material entering the rivers from eucalyptus populations which are interspersed with deciduous woods (those losing their foliage in the autumn). They observed that more material entered the rivers that go through deciduous forests. But, is this material consumed? The fact is that the dead vegetation from deciduous trees enters the rivers at a period when their levels are at their highest and a considerable part of this material is simply carried away downriver; most of the eucalyptus material, on the other hand, being produced in the summer, is retained in the rivers due to the low water levels. Thus, despite dead leaves from the eucalyptus having fewer problems of initial decomposition, i.e. less consumption for the organisms until the phenolic components are eliminated, the research team concluded that this material tends to be used in rivers as much as that from deciduous trees.


'/>"/>

Contact: Amaia Portugal
amaiap@elhuyar.com
34-943-363-040
Elhuyar Fundazioa
Source:Eurekalert

Related biology news :

1. Conference highlights impact of unsettled summer weather on UK marine life
2. Climate projections underestimate CO2 impact
3. The impact of the diffusion of maize to the Southwestern United States
4. Tiny RNA has big impact on lung cancer tumors
5. New neuroimaging analysis technique identifies impact of Alzheimers disease gene in healthy brains
6. USC study finds big air pollution impacts on local communities
7. FSU, Duke partner to study impact of Gulfs dead zone on shrimp fishery
8. Expert to discuss phosphorus impact on Gulf dead zone
9. World interest in Australian fishery impact test
10. Media source impacts ag biotech communication
11. Small mechanical forces have big impact on embryonic stem cells
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/16/2016)... 2016 The global ... reach USD 1.83 billion by 2024, according to ... Technological proliferation and increasing demand in commercial buildings, ... drive the market growth.      (Logo: ... development of advanced multimodal techniques for biometric authentication ...
(Date:6/7/2016)... , June 7, 2016  Syngrafii Inc. and ... business relationship that includes integrating Syngrafii,s patented LongPen™ ... project. This collaboration will result in greater convenience ... credit union, while maintaining existing document workflow and ... ...
(Date:6/2/2016)... Perimeter Surveillance & Detection Systems, ... Infrastructure, Support & Other Service  The latest ... comprehensive analysis of the global Border Security market ... of $17.98 billion in 2016. Now: In ... in software and hardware technologies for advanced video surveillance. ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... ... its second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” Partnering with experienced ... this eBook by providing practical tips, tools, and strategies for clinical researchers. , ...
(Date:6/23/2016)... 23, 2016 Houston Methodist Willowbrook Hospital ... Sports Association to serve as their official health ... Methodist Willowbrook will provide sponsorship support, athletic training ... association coaches, volunteers, athletes and families. ... Sports Association and to bring Houston Methodist quality ...
(Date:6/23/2016)... ... June 23, 2016 , ... ... the launch of the Supplyframe Design Lab . Located in Pasadena, Calif., ... the future of how hardware projects are designed, built and brought to market. ...
(Date:6/23/2016)... -- Andrew D Zelenetz , ... Published recently in Oncology & ... Andrew D Zelenetz , discusses the fact ... placing an increasing burden on healthcare systems worldwide, ... the patents on many biologics expiring, interest in ...
Breaking Biology Technology: