Fungal and bacterial colonisation of Salix pedicellata leaves decaying in permanent and intermittent streams in eastern Morocco

• Published in: International review of hydrobiology. 2001, Vol.86 (3), p.337-348
• Main Authors: MAAMRI, Abdellatif, BÄRLOCHER, Felix, PATTEE, Eric, CHERGUI, Hassan
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Fresh water ecosystems; Freshwater; Fundamental and applied biological sciences. Psychology; Hyphomycetes; Morocco; Morocco, Zegzel R; Salix pedicellata; Synecology
• ISSN: 1434-2944; 1522-2632
• DOI: 10.1002/1522-2632(200106)86:3<337::AID-IROH337>3.0.CO;2-N

Leaf degradation was investigated at four sites in the Zegzel/Cherraa river system (Oueds). Two sites (Upper Zegzel and Lower Zegzel) carry water throughout the year and two (Upstream and Downstream Cherraa) are dry for 5-7 months each year. The dynamics of leaf weight loss and microorganisms associated with Salix pedicellata leaves decaying at the four sites were compared for the first time during the same period over this permanent and intermittent system. Overall decay rates of leaves were significantly higher in the permanent Zegzel stream sections (k = 0.0094 d super(-1) upstream and 0.0056 downstream) than in the intermittently flowing Cherraa sites (k = 0.0046 upstream, and 0.0036 downstream). In the latter, decay was much slower during dry than during wet periods (Upstream Cherraa: k = 0.0028 and 0.0446, respectively; Downstream Cherraa, k = 0.0008 and 0.0357, respectively). Similar gradients from permanent to intermittent sites were observed in numbers of bacteria per unit area or per weight of decaying leaves (direct counts by epifluorescence microscopy), in numbers of fungal species and in sporulation rates, from leaves recovered at the four sites. Ten hyphomycete species were new for Morocco.