Increasing anthropogenic pressure on coastal regions, coupled with a conflicting relationship between ecosystem health and economic growth, has resulted in a worldwide deterioration of marine ecosystems and loss of ecosystem services. The seagrass Posidonia oceanica is an emblematic example, constituting extensive and highly valuable meadows whose extent has largely declined in the last decades.
This study reconstructs more than a century of history of P. oceanica meadows in Liguria (Italy, NW Mediterranean), combining models and historical information. The equivalent economic value of ecosystem function provided at each time and the evolution of the tertiary economic sector, allowed exploring the tradeoffs between economic development and conservation of natural capital in a touristic coastal region.
The obtained results show a loss of more than 50% of the original surface of P. oceanica meadow extent between 1950-1980, followed by a stabilization in the last decades. The accumulated equivalent economic loss due to the decline of P. oceanica meadows was greater than the economic gain in the same time frame expressed as value added of tertiary sector, which in Liguria is mostly linked to tourism-related activities. The results show that the stabilization of P. oceanica meadow extent in the last decades apparently did not affect the gain in the value added, suggesting that investment in nature protection is not in conflict with economic wealth increase.
The authors highlight the need of robust policies to preserve the quality of coastal waters and the physical integrity of the surviving meadows and to maintain, or possibly recover, the ecosystem functions of P. oceanica meadows. And it is concluded that the great potential of ecosystems to provide benefits to human should foster the engagement in more large-scale and long-term measures to preserve ecosystems, considering carefully the tradeoffs between their degradation by wrong-planned actions and short-term benefits.
Burgos E, Montefalcone M, Ferrari M, Paoli C, Vassallo P, Morri C, Bianchi CN (2017) Ecosystem functions and economic wealth: Trajectories of change in seagrass meadows. Journal of Cleaner Production 168:1108-1119