Statistical methods for analysis of seasonal modifications in the salt marshes of the Venice lagoon

Purpose - To define synthetic indices of changes of vegetation coverage on salt marshes of the Venice lagoon that might be used to model changes of the entire basin. Design/methodology/approach - Remote sensing data from the satellite sensor QuickBird were processed to retrieve vegetation coverage in different seasons, i.e. different phenological stages of the halophytic vegetation. These changes have been described by means of landscape metrics (LSM's) and statistical moments. Findings - LSM's selected have been useful to describe the dominant shapes of vegetation coverage, while the low variations occurred were only partially explained. The first four statistical moments have been only partially functional to the description of temporal variation of the patches. Practical implications - These indicators, whose performances have been evaluated by the present work, could be used to detect larger variations on longer period and on wider spatial scale. In this way it could also be possible to easily detect the effects of changes on the hydrodynamic regime that may occur in relation with new projected interventions on the Venice lagoon. Originality/value - This approach has never been applied to salt marshes of the Venice lagoon. The remote sensing data, in particular LSM's and statistical moments applied together, might be valuable tools to detect shape changes in the delicate environment of salt marshes and suggest possible remedies for problems of managing the Venice lagoon.