An improved method to monitor the health of seagrass meadows based on kriging

This paper focuses on the spatial pattern of the shoot density of the seagrass Posidonia oceanica through kriging methods. Kriging is a group of geostatistical techniques to predict the value of a field at an unobserved location from observations of its value at nearby locations. The results of an ordinary kriging of both raw values of shoot density and normalized shoot density with reference to a density vs. depth model (Dn) were compared. Results confirmed the existence of spatially organized parameters other than depth that influence patterns of P. oceanica shoot density. Although still requiring additional testing for complete validation, Dn mapping appears to be a valuable tool to (1) infer causes for the meadow's condition and to design a cost-effective field survey; (2) define areas where protection policies should be undertaken.

► Raw shoot density values do not infer causes for Posidonia oceanica meadow's condition
► Normalized shoot density (Dn) with reference to a density vs. depth model does
► Mapping of Dn is a valuable tool to design field surveys and protection areas.