A decline in primary production in the North Sea over 25 years, associated with reductions in zooplankton abundance and fish stock recruitment

摘要: Phytoplankton primary production is at the base of marine food web; changes in have direct or indirect effects on higher trophic levels, from zooplankton organisms to mammals and seabirds. Here, we present a new time-series gross North Sea, 1988 2013, estimated using in situ measurements chlorophyll underwater light. This shows that recent decades seen significant decline Sea. Moreover, differs magnitude between six hydrodynamic regions within Sea surface warming reduced riverine nutrient inputs are found be likely contributors declining levels production. In turn, correlations observed dynamics including (small) copepods standardized index fish recruitment, averaged over seven stocks high commercial significance Given positive (bottom-up) associations production, abundance stock this study provides strong evidence if continues, knock-on upon productivity fisheries expected unless these managed effectively cautiously.