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Run Scenario Simulations

Subtask Description:
Document results of scenarios.

Action points of the implementation:
The scenarios, the data generated or used for those scenarios, and the outputs of the simulations using those scenarios should be documents as a record of your modelling activity

Result: A description of the scenarios used on the model, and the outputs of those scenarios from model runs.

Area:
Chalastra sea area, Thermaikos Gulf , Greece

Policy Issue:
Sustainable management of mussel culture in the area of Chalastra, Thermaikos Bay

Human Activities:
Mussel aquaculture, agriculture, urban and industrial activities, fisheries.

General Information:
About half of the national mussel harvest is produced in the area. The unique environmental conditions resulted in mussels with very high condition index achieved in a very short time and also in two reproduction and growth circles in the same year. During the last 10 years, mostly due to excessive cultivation techniques, an annual reduction of the mussel production is taking place, both in means of quality and quantity along with an elongation of the growing period. At the same time due to a number of institutional failures, there is an important legal gap creating institutional problems and obstructing the management of the activity, allowing black market, illegal employment, etc. The main stakeholder concerns are connected to the design and implementation of the legal framework and the optimization of the mussel production.

Example of Implementation:
Two main scenarios are implemented:

• Scenario 1. Qualitative and quantitative alteration of agricultural: Evaluation of the impact of the modification of agricultural inputs, quantitatively and qualitatively, on the mussel production of the area.
• Scenario 2. (Basic) Comparable investigation between the present state (random) and the state under the implementation of institutional management: Evaluation of the impact of different management practices, concerning the individual farm and the whole farming area, on the mussel production of the area.

Questions attached to these scenarios are: Is the impact important? What will be the economic impact regarding costs and benefits?

Scenario 1: Qualitative and quantitative alteration of agricultural inputs:

Five runs were conducted related to this scenario. The data input were altered as follows: (1) Current agricultural inputs (no alteration), (2) Double agricultural inputs with the current inorganic nitrogen concentration, (3) Half agricultural inputs with the current inorganic nitrogen concentration, (4) Current quantity with double concentration of inorganic nitrogen, (5) Current quantity with half concentration of inorganic nitrogen. Finally the influence of these alterations to the phytoplanktonic biomass available for mussel consumption was investigated, and is presented in the figure below. It is obvious that the influence is not significant.

The influence of the alteration of agricultural inputs in the phytoplanktonic biomass available for mussel consumption.

Scenario 2: (Basic) Comparable investigation between the present state (random) and the state under the implementation of institutional management:

The table below presents the changing technical drivers and the results regarding the individual, area and total profit on both scenarios.

Estimation of the individual and total profit from the model on both scenarios

Figures present graphically the simulation of production in the four mussel farming areas, demonstrating clearly the high significance of the mussel farming techniques in the production.

Estimated course of the mussel production (kg/m of sock – dry weight) in the four mussel farming areas at the present state scenario.

Estimated course of the mussel production (kg/m of sock – dry weight) in the four mussel farming areas under the institutional management scenario.

Contact: Zoi Konstantinou zkon@civil.auth.gr