MOLTENMOnitoring Long-term Trends in Eutrophication and Nutrients in the coastal zone

Richard Telford Geography Department, Newcastle UniversityStephen Juggins Annemarie ClarkeSimon Drew

Elinor Andren Uppsala University, Sweden

Kaarina WeckströmECRU, University of Helsinki, FinlandAtte Korhola

John Anderson Institute of Geography, Copenhagen University, DenmarkMarianne Ellegaard

Victor de Jonge Dept. Marine Biology, Groningen University, The Netherlands

Heikki Pitkänen Finnish Environment Institute, Finland

Daniel Conley National Environmental Research Institute, Denmark

Determination of reference conditions in coastal and transitional water.

*

*

*

Good Status

The values of the biological quality elements for the surface water body type show low levels of distortion resulting from human activity, but deviate only slightly from those normally associated with the surface water body type under undisturbed conditions.

Table 1.2. General definition for rivers, lakes, transitional waters and coastal watersL 327/38 22.12.2000 Official Journal of the European Communities

Normative definitions of ecological status classifications

…undisturbed conditions

• How can they be defined?

• Quantitative palaeoecology

• Transfer functions

• Multiproxy study

The MOLTEN approach

•Stable isotopes•Pigments•Dinoflagellates•Forams•Diatoms

Actin

opty

chus

sena

rius

Cyclo

tella

cho

cta

whatc

heea

na

Thala

ssio

sira

baltic

a

Hya

lod

iscus

scot

icus

Dim

me

reg

ram

ma

min

or

Rhop

alo

dia

gib

ba

Opepho

ra o

lseni

iDip

lone

is sm

ithii

Nitz

schi

a fi

liform

is

Cocc

oneis

scut

ellu

m

1950

1930

1970

1900

1980

1996

Contemporary water chemistry

Modern diatoms

Calibration dataset

Surface Sample

Fossil diatoms

Sediment core

Transfer Function

Reconstruction

Transfer Function?

Molten Sites

Molten Statistics

Number of Sites 226

Number of Species 852 328 >1%

Salinity ‰ 0.05 31.7

TN g/l 231.8 3890

TP g/l 14.5 463.2

Min Max

Depth m 0.5 50.5

Species response: Rhoicosphenia curvata

pr o

po

rti o

n

5 10 15 20 25 30

0.0

0.0

10

.02

0.0

30

.04

0.0

5

LSalinity (‰)

pro

po

rtio

n

1.4 1.6 1.8 2.0 2.2 2.4 2.6

0.0

0.0

10

.02

0.0

30

.04

0.0

5

LTP (µg/l)

pro

port

ion

2.4 2.6 2.8 3.0 3.2 3.4 3.6

0.0

0.0

10.

02

0.0

30

.04

0.05

LTN (µg/l)

Species response: Cymatosira belgica

pro

porti

on

5 10 15 20 25 30

0.0

0.05

0.10

0.1

50.

20

LSalinity (‰)

prop

ortio

n

1.4 1.6 1.8 2.0 2.2 2.4 2.6

0.0

0.05

0.10

0.15

0.20

GTP (µg/l)

prop

ortio

n

2.4 2.6 2.8 3.0 3.2 3.4 3.6

0.0

0.05

0.10

0.15

0.20

GTN (µg/l)

-3.0

-2.0

-1.0

0.0

1.0

2.0

Ax

Depth

NOn

NH4

TN

PO4

TPChl-a

Secchi Depth

Salinity

Oxygen

NO:POn4

-2.0 -1.0 0.0 1.0 2.0 3.0

Axis 1

is 2

Danish Dataset : CCA biplot showing sites

% Variation explained

total unique

Depth 9.0 6.6

Salinity 6.5 5.3

Secchi 6.2 2.7

NH4 4.9 3.3

TN 4.7 2.5

Predicted vs. measured TN for Danish dataset

RMSE = 0.008 r2 = 0.9

RMSEP = 0.13 r2 = 0.71

Log 1

0 D

iato

m-in

ferr

ed T

N

Log10 Measured TN

Application of the Transfer Function: Roskilde Fjord

Infe

rred

Total

Nitrog

en

Roskilde Fjord Diatom Stratigraphy

http://Craticula.ncl.ac.uk:8000

Conclusions

•There is a significant relationship between diatoms and TN in Coastal and Transitional waters.

•This can be used to estimate background TN levels.

•TN almost doubled in Roskilde Fjord between 1956 and 1995.

•This methodology is being applied to new sites.