Abstract
Key words
Diet; Neotropical region; Lagoa Mirim system; Siluriformes
Key words
Diet; Neotropical region; Lagoa Mirim system; Siluriformes
Food items | Low level (n=21) | High level (n=41) | ||||||
---|---|---|---|---|---|---|---|---|
%F | %N | %A | %IRI | %F | %N | %A | %IRI | |
Acari | 4.9 | 0.3 | 0.1 | 0.1 | ||||
Algae filamentous | 4.9 | 13.5 | 1.2 | 0.9 | 9.5 | 6.4 | 0.6 | 0.8 |
Sand | 26.8 | 0.9 | 6.4 | 2.6 | 14.3 | 0.7 | 1.2 | 0.3 |
Cladocera | 2.4 | 0.9 | 0.2 | 0.1 | ||||
Copepoda | 2.4 | 0.8 | 0.2 | 0.1 | ||||
Diptera (adult) | 4.8 | 0.5 | 0.0 | 0.1 | ||||
Ephemeroptera (adult) | 24.4 | 3.6 | 14.1 | 5.7 | ||||
Hemiptera (adult) | 4.8 | 0.2 | 0.0 | 0.1 | ||||
Coleoptera (larva) | 22.0 | 7.4 | 2.0 | 2.7 | 4.8 | 3.0 | 0.2 | 0.2 |
Diptera (larva) | 9.5 | 0.5 | 0.5 | 0.1 | ||||
Fine particulate matter | 75.6 | 2.4 | 47.2 | 49.5* | 76.2 | 3.7 | 51.9 | 53.3* |
Organic matter | 14.6 | 9.6 | 5.9 | 3.0 | 28.6 | 19.7 | 19.8 | 14.2 |
Vegetable matter | 43.9 | 40.6 | 12.8 | 30.9* | 28.6 | 59.2 | 22.7 | 29.5* |
Nemotoda | 19.0 | 2.5 | 2.0 | 1.1 | ||||
Ostracoda | 4.9 | 0.3 | 0.1 | 0.1 | ||||
Palaemonetes argentinus | 2.4 | 0.1 | 0.4 | 0.1 | ||||
Crustcean remains | 4.9 | 2.0 | 2.8 | 0.3 | 4.8 | 1.1 | 0.4 | 0.1 |
Insect remains | 4.8 | 0.2 | 0.4 | 0.1 | ||||
Seed | 14.6 | 11.8 | 5.5 | 3.4 | 4.8 | 2.3 | 0.2 | 0.1 |
Tecameba | 9.8 | 5.9 | 1.1 | 0.9 | ||||
* Food items larger importance |
Winter (n=8) | Spring (n=10) | Summer (n=24) | Autumn (n=20) | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
%F | %N | %A | %IRI | %F | %N | %A | %IRI | %F | %N | %A | %IRI | %F | %N | %A | %IRI | |
Acari | 8.3 | 0.5 | 0.1 | 0.1 | ||||||||||||
Algae filamentous | 10.0 | 32.2 | 2.8 | 4.7 | 10.0 | 3.2 | 0.3 | 0.4 | 4.2 | 2.2 | 0.5 | 0.1 | ||||
Sand | 12.5 | 2.1 | 2.9 | 0.5 | 35.0 | 1.3 | 8.2 | 4.5 | 20.0 | 0.7 | 1.2 | 0.4 | 16.7 | 0.5 | 3.6 | 0.7 |
Cladocera | 4.2 | 1.3 | 0.2 | 0.1 | ||||||||||||
Copepoda | 4.2 | 1.2 | 0.2 | 0.1 | ||||||||||||
Diptera (adult) | 10.0 | 0.7 | 0.1 | 0.1 | ||||||||||||
Ephemeroptera (adult) | 50.0 | 8.6 | 31.5 | 26.9* | ||||||||||||
Hemiptera (adult) | 12.5 | 2.1 | 0.2 | 0.2 | ||||||||||||
Coleoptera (larva) | 12.5 | 27.1 | 1.1 | 2.9 | 15.0 | 1.1 | 0.2 | 0.3 | 25.0 | 10.5 | 2.5 | 3.3 | ||||
Diptera (larva) | 20.0 | 0.7 | 0.8 | 0.3 | ||||||||||||
Fine particulate matter | 100.0 | 16.7 | 90.8 | 89.2* | 80.0 | 3.0 | 32.7 | 38.3* | 50.0 | 1.8 | 29.2 | 16.9 | 75.0 | 2.1 | 67.5 | 52.4* |
Organic matter | 25.0 | 22.7 | 9.0 | 10.6 | 60.0 | 30.2 | 31.3 | 40.3* | 4.2 | 0.1 | 2.5 | 0.1 | ||||
Vegetable matter | 12.5 | 43.8 | 2.1 | 4.8 | 35.0 | 18.8 | 7.1 | 12.1 | 40.0 | 58.2 | 33.3 | 40.1* | 50.0 | 57.8 | 14.4 | 36.3* |
Nemotoda | 25.0 | 8.3 | 3.0 | 2.3 | 20.0 | 2.5 | 2.5 | 1.1 | ||||||||
Ostracoda | 5.0 | 0.2 | 0.0 | 0.1 | 4.2 | 0.4 | 0.1 | 0.1 | ||||||||
Palaemonetes argentinus | 5.0 | 0.2 | 1.0 | 0.1 | ||||||||||||
Crustcean remains | 10.0 | 4.8 | 6.2 | 1.5 | 10.0 | 1.8 | 0.7 | 0.3 | ||||||||
Insect remains | 10.0 | 0.4 | 0.7 | 0.1 | ||||||||||||
Seed | 5.0 | 1.9 | 0.3 | 0.1 | 25.0 | 17.9 | 7.4 | 6.4 | ||||||||
Tecameba | 10.0 | 5.4 | 1.0 | 0.9 | 8.3 | 5.5 | 0.9 | 0.5 | ||||||||
* Food items larger importance |
Grups | t | p |
---|---|---|
Summer x Autumn | 1.701 | 0.035 |
Summer x Winter | 2.256 | 0.009 |
Summer x Spring | 2.426 | 0.004 |
Autumn x Winter | 1.884 | 0.016 |
Autumn x Spring | 1.603 | 0.067 |
Winter x Spring | 2.857 | 0.004 |
Overall average dissimilarity | Average dissimilarity | Contribution % | |
---|---|---|---|
Summer x Autumn | 61.9 | ||
Fine particulate matter | 22.6 | 36.5 | |
Vegetable matter | 15.3 | 24.7 | |
Summer x Winter | 50.3 | ||
Fine particulate matter | 21.5 | 42.7 | |
Vegetable matter | 17.6 | 35.1 | |
Summer x Spring | 68.9 | ||
Fine particulate matter | 21.7 | 31.5 | |
Organic matter | 20.2 | 29.2 | |
Autumn x Winter | 58.5 | ||
Fine particulate matter | 21.7 | 37.2 | |
Insects | 14.5 | 24.8 | |
Autumn x Spring | 72.2 | ||
Organic matter | 21.6 | 29.9 | |
Fine particulate matter | 16.8 | 23.3 | |
Winter x Spring | 70.9 | ||
Organic matter | 24.7 | 34.7 | |
Fine particulate matter | 21.3 | 30.0 |
Food items | Class 1 (n=6) | Class 2 (n=7) | Class 3 (n=44) | Class 4 (n=4) | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
%F | %N | %A | %IRI | %F | %N | %A | %IRI | %F | %N | %A | %IRI | %F | %N | %A | %IRI | |
Acari | 4.5 | 0.4 | 0.1 | 0.1 | ||||||||||||
Algae filamentous | 16.7 | 44.3 | 5.8 | 9.9 | 14.3 | 12.8 | 2.9 | 1.9 | 4.5 | 1.1 | 0.2 | 0.1 | ||||
Sand | 33.3 | 0.5 | 8.3 | 3.5 | 42.9 | 2.0 | 8.4 | 3.7 | 15.9 | 0.7 | 1.9 | 0.5 | 25.0 | 0.7 | 12.8 | 4.3 |
Cladocera | 25.0 | 8.0 | 1.9 | 3.2 | ||||||||||||
Copepoda | 25.0 | 7.3 | 1.7 | 2.9 | ||||||||||||
Diptera (adult) | 2.3 | 0.2 | 0,1 | 0.1 | ||||||||||||
Ephemeroptera (adult) | 33.3 | 3.1 | 18.2 | 8.4 | 14.3 | 1.4 | 3.5 | 0.6 | 13.6 | 2.8 | 6.2 | 1.6 | ||||
Hemiptera (adult) | 16.7 | 0.3 | 0.1 | 0.1 | ||||||||||||
Coleoptera (larva) | 33.3 | 0.8 | 0.2 | 0.4 | 15.9 | 8.5 | 1.1 | 2.0 | 25.0 | 11.7 | 4.3 | 5.1 | ||||
Diptera (larva) | 14.3 | 0.7 | 0.3 | 0.1 | 2.3 | 0.1 | 0.3 | 0.1 | ||||||||
Fine particulate matter | 100.0 | 1.6 | 49.4 | 60.3* | 85.7 | 4.1 | 56.8 | 43.7* | 70.5 | 3.0 | 50.1 | 48.9* | 75.0 | 2.2 | 33.2 | 34.0* |
Organic matter | 16.7 | 30.6 | 5.8 | 7.2 | 28.6 | 1.4 | 3.6 | 1.2 | 18.2 | 8.4 | 13.7 | 5.2 | 25.0 | 0.7 | 25.6 | 8.4 |
Vegetable matter | 33.3 | 10.9 | 9.8 | 8.2 | 57.1 | 77.7 | 24.5 | 48.9* | 38.6 | 57.8 | 19.0 | 38.8* | 25.0 | 13.9 | 4.8 | 6.0 |
Nemotoda | 16.7 | 0.3 | 0.1 | 6.8 | 1.0 | 1.2 | 0.2 | |||||||||
Ostracoda | 16.7 | 0.3 | 0.1 | 0.1 | 2.3 | 0.3 | 0.1 | 0.1 | ||||||||
Palaemonetes argentinus | 2.3 | 0.1 | 0.3 | 0.1 | ||||||||||||
Crustcean remains | 4.5 | 2.5 | 1.9 | 0.3 | 25.0 | 3.6 | 4.3 | 2.5 | ||||||||
Insect remains | 2.3 | 0.1 | 0.3 | 0.1 | ||||||||||||
Seed | 16.7 | 2.6 | 0.7 | 0.6 | 11.4 | 12.3 | 3.5 | 2.3 | 25.0 | 17.5 | 4.3 | 7.0 | ||||
Tecameba | 16.7 | 4.9 | 1.6 | 1.3 | 2.3 | 1.0 | 0.1 | 0.1 | 50.0 | 34.3 | 7.3 | 26.6* | ||||
* Food items larger importance |