VACEK O., HAVRLAND B., BANOUT J.
Abstract
This article contains information on research which has mapped the development of spontaneous growth of biomass
in "montado" in the Alentejo region of Portugal. The energy potential for commercial use was researched, as well.
The research started 12 years ago. It was necessary, in this very beginning, to protect the monitored area with
fencing from animals, humans and other influences which could distort the research results. Thanks to this we can
consider the research conditions in these locations as being well under control. The main research objective focused
on establishing a model of biomass growth and assessing the overall phytomass energy which could be gained in an
abiotic reactor. The phytomass samples were collected from three zones of the monitored area which were dividend
on the basis of the age of the vegetation. The absolute amount of the biomass was found to be considerably different
in each zone. During the first two time periods the quantity of biomass was increasing; however on the other hand
the quantity of the elder part was decreasing. The maximum amount of shoot biomass was found in the zone which was
nine years old - its average value (dry matter) was 960.74 g/m2. The zone of 12 year-old- biomass produced on average
909.84 g/m2 while the zone of 1.5 year produced 387.63 g/m2. The phytomass samples were tested for energy content too.
The average values of BE (burning energy) were calculated as follows: 18.117; 18.183; 17.921 kJ/g (for 1.5; 9 and
12 year old biomass, respectively). The rough energy content was measured and compared to the comparative fuel unit.
Key words:
biomass, Quercus suber L., Cistus spp., heating value, energy, mitra