TITLE:
Spatial Distribution of Plant-Associated Invertebrates and Environmental Bioassessment in a Natural Riverine Lake (Lake Fibreno, Central Italy)
AUTHORS:
Luciana Mastrantuono, Valentina Di Vito, Marcello Bazzanti
KEYWORDS:
Macrophytes, Meio- and Macroinvertebrates, Mediterranean Riverine Lake, Ecological Bioassessment
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.6 No.10,
July
30,
2014
ABSTRACT:
Lake
Fibreno is a Mediterranean riverine lake located in Central Italy and fed by large
flows of groundwater and characterized by the presence of a wide reed
stand area and of the only floating island of the South Europe. It is enclosed in a
Natural Reserve recognized as Special Area of Conservation (SAC-IT6050015) for
the presence of habitats and species (92/43/EEC) of relevant scientific
interest. In this
paper, we compare the plant-associated meio-macrobenthic invertebrates among
sites with different environmental characteristics. Both vegetation and
invertebrates of Lake Fibreno were well diversified and abundant and were
composed of a mixing of species typical of lentic and lotic waters. Our results
show that a gradient of orthophosphate and nitrite contents and current
velocity appeared to be the driver factors affecting the flora and fauna
spatial distribution at the sampling sites. To obtain a bioassessment of the
ecological quality of the vegetation zone, we compared the riverine Lake
Fibreno with typical lentic lakes previously studied in Central Italy. We
selected metrics, such as macrophyte belt extent and taxa richness, invertebrate species
richness and Shannon diversity, ETOM (Ephemeropta + Trichoptera + Odonata + Mollusca), ETOC (Ephemeropta +
Trichoptera + Odonata + Coleoptera) and LCrM (Large Crustacea + Mollusca). The
comparison indicated a good ecological status of the vegetation zone of Lake Fibreno mainly
due to the continuous washout
effects (dilution and fast water removal) which reduce the nutrient content
available for phytoplankton and maintain the high transparency and good
oxygenation of the lake waters.