Changes in an East African social-ecological seagrass system: invertebrate harvesting affecting species composition and local livelihoodLina Nordlund, Johan Erlandsson, Maricela de la Torre-Castro and Narriman JiddawiAquat. Living Resour., 23 4 (2010) 399-416DOI: https://doi.org/10.1051/alr/2011006