Table 1 Overview of the parameters acquired from the Microbiology Department of the Biologische Anstalt Helgoland at the sampling station “Kabeltonne”, Helgoland Roads from 1962 until today. Samples were mostly taken at weekly intervals. AODC acridine orange direct counting; BOD biological oxygen demand; CFU colony-forming units; DGGE denaturing gradient gel electrophoresis; F-DC flagellates direct counting; FBC flowcytometric bacterial counts; ODB oil-degrading bacteria; TOC total organic carbon; VLP-DC virus-like particles direct counting

AODC

Pelagic

Jan 1987

now

1, 2, 3, 4, 5, 6, 7

Neuston

Jan 1987

June 1993

1

F-DC

1 m

Jan 1990

now

6

VLP-DC

1 m

Jan 2000

now

1, 3

FBC

1 m

June 1996

July 1998

1, 3

CFU

1 m

pouring plate technique

2216EM

Jan 1962

Dec 1995

1 m

2216ES

May 1963

June 1993

Neuston

2216EM

Aug 1973

Dec 1995

Neuston

2216ES

Aug 1973

Dec 1995

1 m

spread plate technique

2216EM

June 1993

Apr 2000

6

1 m

2216ES

June 1993

Apr 2000

1 m

1/10 2216EM

June 1993

Apr 2000

1 m

1/10 2216ES

June 1993

Apr 2000

1 m

2216EM-CdCl₂

June 1993

Dec 1995

1 m

2216EM-HgCl₂

June 1993

Dec 1995

Yeasts

1 m

Jan 1966

Dec 1971

Jan 1980

Dec 1992

11

Luminescent bacteria

1 m

Jan 1981

Dec 1983

ODB

1 m

Jan 1965

Dec 1967

Jan 1980

June 1993

9

BOD

1 m

Jan 1965

June 1993

10

Surface tension

Neuston

Apr 1972

Oct 1992

1 m

Apr 1972

Oct 1992

ATP

Neuston

Dec 1989

May 1993

1 m

Dec 1989

May 1993

7

TOC

Neuston

Jan 1980

Dec 1984

1 m

Jan 1980

Dec 1984

Ectoenzymatic activity

1 m

Jan 1995

Oct 1996

8

PCR-DGGE

1 m

>3 μm

Aug 1996

July 1999

5

0.2 μm–3 μm

Aug 1996

July 1999

5