Natural resources and climate change: A study of the potential impact on Manila clam in the Venice lagoon.

A crucial aspect in climate change is to understand how an ecosystem will adapt under different environmental conditions and how it will influence the ecological resources and the connected human activities. In this study, a numerical model reproduces the growth dynamics, dispersion and settlement of clam's larvae in the Venice lagoon. On the basis of the last IPCC scenarios for the years 2050 and 2100, the model simulates the changes in larval settlement, showing how the geographical distribution and, consequently, the nursery area changes over time. Our results indicate that climate change will modify, not only the timing of the settlements (from spring-summer to winter autumn) and the spatial distribution of nursery areas (from central to southern lagoon), but also the absolute quantity of settled larvae in the lagoon. This can strongly affect aquaculture in terms of availability of seed and farming practice. Given that these changes are due to the variations in temperature and circulation, similar processes are likely to happen in other transitional environments all over the world affecting the global aquaculture resources. In this regard, the tool we developed could support local policymakers in the knowledge-based planning and sustainable management of clam aquaculture in vulnerable environments.