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Registro Completo |
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Biblioteca(s): |
Embrapa Pantanal. |
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Data corrente: |
21/06/1995 |
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Data da última atualização: |
21/06/1995 |
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Autoria: |
ENGELMANN, M. D. |
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Título: |
The role of soil arthropods in the energetics of an old field community. |
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Ano de publicação: |
1961 |
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Fonte/Imprenta: |
Ecological Monographs, v.31, n.3, p.221-238, Summer, 1961. |
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Idioma: |
Inglês |
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Conteúdo: |
1. In 1958 a field sampling program and laboratory studies were undertaken with the soil arthropods of an old field in south-eastern Michigan to elucidata the energy dynamics of the soil system. Laboratory methods involved Tullgren extraction, biomass determination, respiration studies and calorimetry. 2. An energy abalanze sheet was drawn up for the oribatid mites. It was calculated that these mites in 1 sqaure meter 12.5 em deep consumed 10,248 calories of food each year and assimilated 2,058 calories or 20% of the food ingested. Respiration accounted for 96% and mortality for 20% of the assimilated material. The error for the calculation was 13%. 3. when comparison was made with the data obtained by Hairston & Byers (1954) on the same field, it was found that the oribatid mite populations had changed markedly. The species composition had changed completely save for 5 species. Numbers of individual had decreased 33% between 1950 and 1958, but the biomass and calories of respiration had doubled or almost so. It is suggested that the oribatid fauna has probably displaced other components of the soil, and that the total arthropod biomass has remained at a constant level. 4. The ecological efficiency was calculated for the soil arthropods. Due to the lack of certain feeding information, renable efficiencies ranged from 8% to 30% for the soil herbivores. 5. When energy units (respiration calories) were used in place of numbers of individuals in one of MacArthur's models, the observed curves more nearly fir the predicted curves, lendinga support to the idea that the niche is the amount and kind of food a population sonsumes. 6. The main role of the soil herbivores was found to be that of controlling the fungal and bacterial popaulations which are breaking down the dead materials. These arthropods can both accelerate and retard the growth of the decay organisms. The soil carnivores serve as population controls on the herbivores. 7. The soil system is considered for two reasons to be a community separate from the above-ground system. First, it as a trophic level system siamilar to athat of the above-ground system, and secondly, changes in species composition in the soil arthropods are apoparently independent of changes in the above-ground system. 8. Data on Daphuia pulex, the water flea, and Oppia nova, an oribatid mite, compared favorably with respect to their respiration and assimilation efficiencies. The range of ecological efficiencies (8.5- 30%) for the soil herbivores compared favorably with ecological efficiencies for the same trophic level in the aquatic communities, and the 1.5- 2.0% efficiency of transfer to each level in the soil community also fell within the range of efficiencies found for the aquatic communities. These data lend support to the hypothesis that all communities operate on the same energetic principles. Menos1. In 1958 a field sampling program and laboratory studies were undertaken with the soil arthropods of an old field in south-eastern Michigan to elucidata the energy dynamics of the soil system. Laboratory methods involved Tullgren extraction, biomass determination, respiration studies and calorimetry. 2. An energy abalanze sheet was drawn up for the oribatid mites. It was calculated that these mites in 1 sqaure meter 12.5 em deep consumed 10,248 calories of food each year and assimilated 2,058 calories or 20% of the food ingested. Respiration accounted for 96% and mortality for 20% of the assimilated material. The error for the calculation was 13%. 3. when comparison was made with the data obtained by Hairston & Byers (1954) on the same field, it was found that the oribatid mite populations had changed markedly. The species composition had changed completely save for 5 species. Numbers of individual had decreased 33% between 1950 and 1958, but the biomass and calories of respiration had doubled or almost so. It is suggested that the oribatid fauna has probably displaced other components of the soil, and that the total arthropod biomass has remained at a constant level. 4. The ecological efficiency was calculated for the soil arthropods. Due to the lack of certain feeding information, renable efficiencies ranged from 8% to 30% for the soil herbivores. 5. When energy units (respiration calories) were used in place of numbers of individuals in one of MacArthur's models, the ob... Mostrar Tudo |
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Palavras-Chave: |
Artropode; Community; Comunidade. |
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Thesagro: |
Ecologia; Solo. |
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Thesaurus Nal: |
arthropods; ecology; soil. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 03429naa a2200217 a 4500
001 1784642
005 1995-06-21
008 1961 bl --- 0-- u #d
100 1 $aENGELMANN, M. D.
245 $aThe role of soil arthropods in the energetics of an old field community.
260 $c1961
520 $a1. In 1958 a field sampling program and laboratory studies were undertaken with the soil arthropods of an old field in south-eastern Michigan to elucidata the energy dynamics of the soil system. Laboratory methods involved Tullgren extraction, biomass determination, respiration studies and calorimetry. 2. An energy abalanze sheet was drawn up for the oribatid mites. It was calculated that these mites in 1 sqaure meter 12.5 em deep consumed 10,248 calories of food each year and assimilated 2,058 calories or 20% of the food ingested. Respiration accounted for 96% and mortality for 20% of the assimilated material. The error for the calculation was 13%. 3. when comparison was made with the data obtained by Hairston & Byers (1954) on the same field, it was found that the oribatid mite populations had changed markedly. The species composition had changed completely save for 5 species. Numbers of individual had decreased 33% between 1950 and 1958, but the biomass and calories of respiration had doubled or almost so. It is suggested that the oribatid fauna has probably displaced other components of the soil, and that the total arthropod biomass has remained at a constant level. 4. The ecological efficiency was calculated for the soil arthropods. Due to the lack of certain feeding information, renable efficiencies ranged from 8% to 30% for the soil herbivores. 5. When energy units (respiration calories) were used in place of numbers of individuals in one of MacArthur's models, the observed curves more nearly fir the predicted curves, lendinga support to the idea that the niche is the amount and kind of food a population sonsumes. 6. The main role of the soil herbivores was found to be that of controlling the fungal and bacterial popaulations which are breaking down the dead materials. These arthropods can both accelerate and retard the growth of the decay organisms. The soil carnivores serve as population controls on the herbivores. 7. The soil system is considered for two reasons to be a community separate from the above-ground system. First, it as a trophic level system siamilar to athat of the above-ground system, and secondly, changes in species composition in the soil arthropods are apoparently independent of changes in the above-ground system. 8. Data on Daphuia pulex, the water flea, and Oppia nova, an oribatid mite, compared favorably with respect to their respiration and assimilation efficiencies. The range of ecological efficiencies (8.5- 30%) for the soil herbivores compared favorably with ecological efficiencies for the same trophic level in the aquatic communities, and the 1.5- 2.0% efficiency of transfer to each level in the soil community also fell within the range of efficiencies found for the aquatic communities. These data lend support to the hypothesis that all communities operate on the same energetic principles.
650 $aarthropods
650 $aecology
650 $asoil
650 $aEcologia
650 $aSolo
653 $aArtropode
653 $aCommunity
653 $aComunidade
773 $tEcological Monographs$gv.31, n.3, p.221-238, Summer, 1961.
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Registro original: |
Embrapa Pantanal (CPAP) |
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