| | | 18.1 Introduction |
As in many coastal environments throughout the world, the watersheds of the Adriatic Sea are regions of rapid population growth and changing land-use patterns that have led to increases in nutrient loading and changes in freshwater flow patterns to coastal waters that have been especially pronounced during the last 100 years. The Adriatic region is characterized by intensive land-based and sea-based activities, including urban growth and development, agriculture, commercial and recreational fisheries, tourism, and multinational commerce. Changes in these activities are widely believed to have elicited significant degradation of water quality, manifested as mucilage events, oxygen depletion of bottom water, harmful algal blooms, outbreaks of gelatinous zooplankton, invasions of non-indigenous species, loss of habitat and instability of fisheries. Individually, these phenomena may not be cause for concern. But taken as a whole, they may be indicative of a pattern of environmental stress that threatens the health of coastal ecosystems of the Adriatic.
Although there are many uncertainties, it was concluded that the weight of scientific evidence from the Adriatic and elsewhere supports the hypothesis that mucilage events, oxygen depletion, harmful algal blooms, and the sustainability of fisheries may be related to each other and to increases in nutrient loading from human sources. The common denominator in this scenario is the response of the food web to nutrient inputs and the harvesting of fish (from the WORKSHOP REPORT on "Nutrient and Trophic Dynamics in the Adriatic Sea: Toward a Coordinated Adriatic Observing System." Rovinj, Croatia, 17-23 October 1999).
| | | 18.1 Introduction |