Spectral reflectance profile of Caulerpa racemosa var. cylindracea and Caulerpa taxifolia in the Adriatic Sea

Abstract

          The invasive algae in the Mediterranean Caulerpa taxifolia and Caulerpa racemosa var. cylindracea have gained much interest in the Adriatic Sea due to their fast spread and negative impacts on native seaweed species. Lack of accurate mapping and its overall high costs represent some of the major difficulties for successful detection and subsequent environmental management. Remote sensing techniques could provide a quicker, more accurate and more cost efficient approach to mapping these invasive species. In order to allow for classification of remotely sensed data, we have collected and analyzed hyperspectral reflectance profiles of both invasive Caulerpa species in the Adriatic and the native Caulerpa cf. laetevirens species from the southeastern Atlantic coast of the United States. We have measured distinctive spectral features for spectroscopically distinguishing between these species, which is particularly interesting in the areas where these native and invasive species coex-ist. The initial results suggest that it might be possible to distinguish between the species based on their spectral reflectance profile. These results would have to be verified with samples taken from more populations in different phenological phases of the seaweed growth and other environmental conditions.