Human Disturbance in a Tropical Rocky Shore Reduces Species Diversity.

Abstract

Human activities in coastal areas may threaten biological communities and lead to the loss of biodiversity. This study compares the impact of human trampling on macrobenthic communities found in the low-, mid-, and high-tidal zones of the Rumassala Marine Sanctuary and two adjacent localities, Galle and Unawatuna. We used univariate measures, species area curves, and diversity indices to discriminate the impact of human activity on the rocky shore community assemblages. Results from index of disturbance of macrofauna and macroflora in more frequently visited sites like Galle and Unawatuna indicate that human presence tends to negatively affect the benthic assemblages; in contrast, human disturbance has a lower influence in Rumassala. There were more macrobenthic species in Rumassala (81) than in Galle (59) or Unawatuna (52), and Margalef’s and Shannon’s diversity indices, respectively, indicate the same trend, i.e., Rumassala (9.42, 3.17), Galle (7.21, 3.13), and Unawatuna (6.74, 2.90).