Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Savafor: determining the productivity of savannahs

24.05.2006


Wood is the main energy source in the Sahel. In order to plan for changes in stocks, it is essential to be able to produce a common estimate of the productivity of savannahs in all the countries concerned. This is the aim of the Savafor network, which was founded recently.



Wood and charcoal cover a substantial part of domestic energy requirements in Sahel countries: from 47% of requirements in Senegal to 96% in Chad, according to a 1986 FAO study. Wooded formations, primarily dry savannahs, are thus under substantial logging pressure, particularly around towns. The FAO has put the annual rate of forest shrinkage in Sahelo-Sudanian Africa at 0.72% (2001).

As a result of this loss of resources, traders in Bamako, Mali, are now having to bring in supplies from as far away as 200 km from the city. This reduction in forest cover could be slowed through plans to develop village forests, in the hope of balancing the volumes logged and natural renewal of stocks. However, such an operation means determining wood stock growth rates more precisely.


Several summaries of the information available on savannah productivity have been produced since the 1980s. However, these studies have never been coordinated, and a consensus has never been reached on the value of savannah productivity, or on the ways of estimating that prioductivity. An effort thus needs to be made to coordinate operations so as to capitalize on the research already done on savannah productivity on a regional scale. This gave rise to the recent creation of a regional scientific network, Savafor.

It includes some twenty researchers from West and Central Africa, representing twelve research institutes or organizations, including CIRAD. Three questions in particular are at the heart of their work: How can we estimate productivity? What experimental designs and types of measurements are required? How can we build a sustainable skills network on this issue? The first necessity is to standardize measurement methods. This will be followed by joint analyses on a regional scale, based on data obtained from the existing installations in North Cameroon, Mali and Burkina Faso.

The problem is that for a given rainfall level, productivity estimates may vary by a factor of one to six, depending on the study. These variations can primarily be put down to a lack of harmonization of the various measurement protocols in terms of the tree components taken into account when defining firewood. The appropriateness of the very concept of productivity also needs to be reviewed.

Productivity is a dynamic concept, which varies in line with the stage of stand development. Determining it on an overall level, on the scale of a forest, is of no relevance except with a view to the exclusive exploitation of a single resource, occasionally and by clear cutting. However, local populations in fact use savannahs in a more subtle way: many species are used and satisfy many different needs, with fuelwood being just one in a range of uses. Moreover, the logging practises used do not correspond to clear cutting, but rather to a selection system. The productivity concept should thus move more towards one of forest dynamics, so as to take account of this type of use.

Nicolas Picard | alfa
Further information:
http://www.cirad.fr
http://www.cirad.fr/en/actualite/communique.php?id=458

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Getting electrons to move in a semiconductor

25.04.2018 | Physics and Astronomy

Reconstructing what makes us tick

25.04.2018 | Physics and Astronomy

Cheap 3-D printer can produce self-folding materials

25.04.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>