TITLE:
Evaluation of the Above-Ground Biomass of Steppe Ecosystems According to Their Stage of Degradation: Case of the Area of Ain Skhouna (Western Algeria)
AUTHORS:
Abdeslam Morsli, Okkacha Hasnaoui, Fatiha Arfi
KEYWORDS:
Vegetation, Evaluation, Biomass, Degradation, Ain Skhouna, Algeria
JOURNAL NAME:
Open Journal of Ecology,
Vol.6 No.5,
April
20,
2016
ABSTRACT: The steppe in the region of Ain Skhouna (Department of Saida) includes three major
vegetation types: Stipa tenacissima, Artemisia herba alba and Lygeum spartum. They have a very important ecological and socio-economic role. Nevertheless, they
are exposed to a threat of deterioration due essentially to a combination of
adverse climate circumstances and human impact. In the field, we found three
physiognomic stages for each type of vegetation: degraded, moderately degraded
and well growing. For a better comprehension of the process of each facies, we
considered that the dynamic of the above-ground biomass is an interesting
indicator for quantifying the degree of degradation of the steppic ecosystems.
For that, we have adopted a combined method: linear transects and vegetation
harvests over a one-square meter surface. This approach allowed us to identify
the chosen site taxa on the one hand and quantify the above-ground biomass of
each plot on the other hand. The obtained results reveal a significant regression
of the above-ground biomass when moving from one site to another. The values
about the Stipa formations present an average biomass oscillating
between 1024 and 271.7 kg DM/ha for perennial species and between 367 and 68.8
kg DM/ha for annuals. Those about Artemisia formations fluctuate between
3584 and 805 kg DM/ha for perennials and between 524 and 66 kg DM/ha for
annuals. Those about Lygeum formations oscillate between 274.4 and 87.9
kg DM/ha for perennial species accompanying Lygeum spartum and between
162.3 and 31.6 kg DM/ha for annuals.