Ticket #540 (closed assessed: wontfix)

Opened 10 years ago

Last modified 5 years ago

Network Analysis: MTI

Reported by: carieh Owned by: villyc
Priority: normal Milestone: Ecopath 5: build 5.2
Component: Network Analysis plug-in Version:
Severity: minor Keywords:
Cc:

Description (last modified by jeroens) (diff)

From ecopath.org user:Alberto Barausse
This is not precisely a bug according to the standard meaning, but in the MTI analysis discarded groups are positively impacting the fleet that discards them, i.e. I believe they are treated as landings making up the fleet diet matrix. If I am right (this is what clearly appears from my model) I think the routine should be corrected.

Hi guys,
I tried to test this by opening the generic model
-copying the Mixed Trophic Index for the model
-adding discards to small reeffish (they currently do not affect the fishery)

(I added 0.1 t/km2 discards)

-recalculating the MTI

The MTI for reeffish small (xaxis) to fleet 1 (yaxis) changed from 0.0046 to 0.021 so in my opinion the reeffish is having a positive effect on the reeffish?

The MTI for fleet 1 (xaxis) to reeffish small (yaxis)changed from 0.2473
to 0.2473 so no change.

I am not sure why the fish are having a positive effect on the fishery when they are ONLY inserted as discards, perhaps some interactions that are not direct between the two. I am struggling with how to answer this for the user, and I am not sure it is actually a bug, so I will assign to Villy. (sorry Villy)

Change History

comment:1 Changed 10 years ago by villyc

I've fixed this, Alberto is right. DCCnoDiscard added. A fleet will still have a negative impact on its discards, but the discarded group will not have a positive impact on the fleet

comment:2 Changed 9 years ago by jeroens

  • Component changed from Contaminant tracing to Plug-ins
  • Description modified (diff)

comment:3 Changed 9 years ago by jeroens

  • Status changed from assigned to closed
  • Resolution changed from open to fixed

comment:4 Changed 9 years ago by jeroens

  • Status changed from closed to reopened
  • Resolution fixed deleted
  • Milestone changed from Ecopath 6 to Ecopath 5

This bug has not been addressed in EwE5. Needs fixing too?

comment:5 Changed 9 years ago by jeroens

  • Owner changed from carieh to villyc
  • Status changed from reopened to assigned

comment:6 Changed 9 years ago by shermanl

  • Type set to not assessed

comment:7 Changed 9 years ago by jeroens

  • Type changed from not assessed to assessed

comment:8 Changed 9 years ago by shermanl

  • Milestone changed from Ecopath 5: build 5.1 to Ecopath 5: build 5.2

comment:9 Changed 9 years ago by jeroens

  • Component changed from Plug-ins to Network Analysis

comment:10 Changed 5 years ago by jeroens

  • Status changed from assigned to closed
  • Resolution set to wontfix
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