Aqua Case Aqua Case Musselculture area-Musselculture area-

Chalastra ThessalonikiChalastra ThessalonikiExercise

Find the appropriate distance between mussel socks based on the mussel condition index

Sofia Galinou-Mitsoudi, Ourania Giannakou, Amalia Moriki

The subjectThe subject

The farmers of Chalastra hang the suspended socks densely, leaving <40 cm between them.

This operation exhausts the carring capacity of the mussel farm area producing underfed mussels.

Mussel quality declinesThe future sustainability of the mussel activity in

Chalastra is questionable.

The challengeThe challengeTo find the most appropriate distance between

socks for the Chalastra environment.To help farmers understand why they have to

change their practices.

Questions to answer: In a mussel culture area, is the expression

“more effort, more production" true? How do we find the best distance between

socks (e.g. 50, 60 or 90 cm)? Which simple condition index is representative?

Learning goalsLearning goalsTo understand the connection between

production quality and farming practices.To identify mussel quality in terms of

condition index, using different distances between socks.

To understand the temporal variability of the mussel condition index for production quality.

To estimate the benefits of different practices on yields and production costs.

In addition to the case the In addition to the case the following information is suppliedfollowing information is supplied• GRAPH: Temporal variability of Hellenic

mussel production and its benefit

• MAP: Water drainage area and human activities

• MAP: The extent of the mussel culture activity in Chalastra

• MAP: The hydrodynamism of the area

• MAP: Levels of chl-a in the mussel culture area of Chalastra

The Hellenic mussel production and its benefit (Source: Eurostat)

The water drainage area and the human activities

The size of the mussel culture activity in Chalastra

NCMR, 2000 with modifications

The currents in mussel culture area of Chalasta for NW prevailing winds

20 40 60 80 100 120 140

20

40

60

80

100

20 40 60 80 100 120 140

20

40

60

80

100

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

0.11

0.12

0.13

0.14

ATEITH, 2007

Levels of chl-a in the musselculture area of Chalastra

SoHelMe, 2005 with modification

Notes for teachersNotes for teachers

Current status of the mussel culture activity

Current local practices vs. legislation

The authorities plans

Sociology of the farmers

Additional Sources/References