Long-term trends in eutrophication and nutrients in the coastal zone

TY - JOUR

T1 - Long-term trends in eutrophication and nutrients in the coastal zone

AU - Clarke, Anne-Marie

AU - Weckström, Kaarina

AU - Conley, Daniel

AU - Anderson, N. John

AU - Adser, Finn

AU - Andrén, Elinor

AU - de Jonge, Victor

AU - Ellegaard, Marianne

AU - Juggins, S.

AU - Kauppila, P.

AU - Korhola, A.

AU - Reuss, Nina Steenberg

AU - Telford, R. J.

AU - Vaalgamaa, S.

PY - 2006

Y1 - 2006

N2 - We used high-resolution paleoecological records of environmental change to study the rate and magnitude ofeutrophication over the last century in two contrasting coastal ecosystems. A multiproxy approach using geochemicaland biological indicators and diatom-based transfer functions provides a long-term perspective on changes in nutrientconcentrations and the corresponding biological and sedimentary responses. In Roskilde Fjord, Denmark, totalnitrogen (TN) increased 85% during the last century, with the most rapid increase occurring after the 1950s,corresponding to the postwar increase in N fertilizer use. In Laajalahti Bay, an urban embayment near Helsinki,Finland, total dissolved nitrogen (TDN) increased with growing wastewater inputs and decreased with the remedialactions taken to reduce these discharges. These changes are small relative to the order of magnitude increases innutrient loading that have occurred in northwestern Europe, where the dissolved inorganic nitrogen (DIN) load hasincreased more than threefold in certain areas.

AB - We used high-resolution paleoecological records of environmental change to study the rate and magnitude ofeutrophication over the last century in two contrasting coastal ecosystems. A multiproxy approach using geochemicaland biological indicators and diatom-based transfer functions provides a long-term perspective on changes in nutrientconcentrations and the corresponding biological and sedimentary responses. In Roskilde Fjord, Denmark, totalnitrogen (TN) increased 85% during the last century, with the most rapid increase occurring after the 1950s,corresponding to the postwar increase in N fertilizer use. In Laajalahti Bay, an urban embayment near Helsinki,Finland, total dissolved nitrogen (TDN) increased with growing wastewater inputs and decreased with the remedialactions taken to reduce these discharges. These changes are small relative to the order of magnitude increases innutrient loading that have occurred in northwestern Europe, where the dissolved inorganic nitrogen (DIN) load hasincreased more than threefold in certain areas.

M3 - Journal article

SN - 0024-3590

VL - 51

SP - 385

EP - 397

JO - Limnology and Oceanography

JF - Limnology and Oceanography

IS - 1, part 2

ER -