Difference in EE estimates between Ecopath and Rpath

[max-cosme]

Hi !

I tried to estimate parameters from a same set of basic inputs and diet compositions in Ecopath and Rpath.

• Basic inputs : toy_basic_input.csv
• Diet compositions : toy_diet_composition.csv

Everything works fine, except for Ecotrophic Efficiency (EE).

I've tried diving into the rpath() function but I can't see where the problem is coming from.

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Rpath results

Group	type	TL	Biomass	PB	QB	EE	GE
Predator	0	3.173469	1	2	10	0	0.2000000
H1	0	2.224490	1	10	19	0	0.5263158
H2	0	2.122449	1	10	20	0	0.5000000
Plant	1	1.000000	10	50	0	1	0.0000000
Detritus	2	1.000000	1	0	0	0	0.0000000
Fishers	3	1.000000	0	0	0	0	0.0000000

Ecopath results

Group	type	TL	Biomass	PB	QB	EE	GE
Predator	0	3.173	1	2	10	0	0.2
H1	0	2.224	1	10	19	0.7	0.526
H2	0	2.122	1	10	20	0.88	0.5
Plant	1	1	10	50	0	1
Detritus	2	1	1	0	0	0
Fishers	3	1	0	0	0	0

[Clara-yong]

Hi!

I am new to RPath and am facing a similar issue except that my Rpath results returned "0" EE for all groups. It also gave very different results when I ran Rsim.

Basic Parameters:
Model BP.csv

Diet composition:
Model DC.csv

R code:
Rpath EE troubleshoot.txt

Ecopath with Ecosim output

<style> </style>

Group name	Trophic level	Hab area (proportion)	Biomass in habitat area (t/km²)	Biomass (t/km²)	Production / biomass (/year)	Consumption / biomass (/year)	Ecotrophic Efficiency	Production / consumption (/year)
C2	4	1	0,5	0,5	1	4	0	0,25
C1	3	1	1	1	5	12,5	0,4	0,4
Zooplankton	2	1	2	2	10	50	0,625	0,2
Phytoplankton	1	1	5	5	100		0,2
Detritus	1	1	10	10			0

RPath output

<style> </style>

Group	type	TL	Biomass	PB	QB	EE	GE	Removals
Gastropod	0	4	0.5	1	4	0	0.25	0
Coral	0	3	1	5	12.5	0	0.4	0
Zooplankton	0	2	2	10	50	0	0.2	0
Phytoplankton	1	1	5	100	0	0	0	0
Detritus	2	1	10	0	0	0	0	0
Fleet	3	1	0	0	0	0	0	0

Ecosim output
Basic model_troubleshooting EE_EwE.csv

--summarized--

<style> </style>

Pane	Cumulative biomass
Data	1: C2	2: C1	3: Zooplankton	4: Phytoplankton	5: Detritus
0	0.5	1	2	5	10
1.083333	0.500005	1.000028	2.000021	4.99997	9.999887
1.166667	0.500005	1.00003	2.000115	5.000002	9.99988
…
101	0.5	1.000001	2	5	9.999868

Rsim output

<style> </style>

Group	StartBio	EndBio	BioES	StartCatch	EndCatch	CatchES
Outside	1	1	1	0	0	NA
C2	0.5	5.00E-16	1.00E-15	0	0	NA
C1	1	0.0114	0.0114	0	0	NA
Zooplankton	2	1.0109	0.50545	0	0	NA
Phytoplankton	5	3.815773	0.763155	0	0	NA
Detritus	10	40225.39	4022.539	0	0	NA
Fleet	0	0	NA	0	0	NA