Wave exposure

Poland habitat mapping Oslo Workshop

2007-05-29

Martin Isæus

08-16 10 11martin.isaeus@aquabiota.se

Effekter på biotan

Direct effects Pressure and drag forcesWater movements, whip-lash etc

Indirect effectsSorting of sediments, erosion

Correlations with secchi-depth and salinity

Example from Askö

SweExp

NorExpFinExpBaltExp?ThaiExp?

SweExp Bohuslän

Preliminär klassning

Detalj Väderöarna

Detalj Väderöarna

Sites for Biological exposure index

BioEx

R2 = 39.6

STWAVE

R2 = 36.2

SWM

R2 = 55.2

FWM

R2 = 48.9

High

energy

Moderate

energy

Low

energy

Sheltered

Very sheltered

Extremely sheltered

Ultra sheltered

Exposed

Extremely exposed

Moderately exposed

Very exposed

Used for preliminary exposure classes

List of A1 species

Field stations

Opstad 1981

Lein et al 1998

Klavestad 1954

Iversen 1981

A1 n = 233

A3 n = 126

Histogram (A1, Himanthalia elongata)

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

LogSWM

11%

21%

32%

43%

54%

Pe

rce

nt

of

ob

s

Histogram (A1, Ascophyllum nodosum)

5 6 7 8 9 10 11 12 13 14

LogSWM

0102030405060708090

No

of

ob

s

Histogram (A3, Ruppia maritima)

5 6 7 8 9 10 11 12 13 14 15

LogSWM

02468

1012

No

of o

bs

Examples on species distributions in relation to wave exposure