Georeferenced SCUBA dive for plant cover estimation in the ‘Pescara Springs’ (Sorgenti del Pescara, Popoli, Italy)

ABSTRACT

Self-Contained Under-water Breathing Apparatus (SCUBA) dive has been applied to the superficial waters of the Pescara Springs (Sorgenti del Pescara, Popoli, Italy) to estimate the plant cover for biomonitoring scope, according to Water Framework Directive 2000/60/EC. In particular, the photointerpretation of georeferenced images taken during the dive was adopted in order to evaluate submersed hydrophytes cover and to evaluate Macrophyte Biological Index for Rivers. One hundred and eighty-one digital images (a picture every 5.3 m on average) were taken during the dive span (956 m). The estimation of the percentage of vegetation cover according to species was performed by means of the photointerpretation of the aforementioned digital images. The area (in m²) determined by orthophoto photointerpretation was divided for the total length of each tract, and the result was then multiplied for the length of each segment connecting each georeferenced, sampling point, in order to estimate the area of the single sampled site. Plant cover estimation obtained by means of georeferenced SCUBA dive appeared to be comparable with the data obtained from previous surveys and appeared to be a reliable, complementary method in submerged plant cover estimation for biomonitoring purposes.

KEYWORDS:

• Biomonitoring
• scientific diving
• lotic ecosystem
• sampling method
• river

Acknowledgement

Present survey is part of a Master of Science degree dissertation of the author. The thesis in Environmental Science was discussed on 23 March 2012 at University of L'Aquila. A modified version of the final dissertation was published by the authors (book on demand) (Manera 2012). Orthophoto has been kindly provided by the Cartographic Office of Abruzzo Region, authorization date 2 April 2012. Thanks are due to Daniele Cargini, Sara Nicolai and Carla Giansante for the technical aid provided in plant sampling and identification and for the logistic support.

Disclosure statement

No potential conflict of interest was reported by the author.