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Registro Completo |
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Biblioteca(s): |
Embrapa Florestas. |
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Data corrente: |
22/09/2008 |
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Data da última atualização: |
22/09/2008 |
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Autoria: |
HEDDE, M.; BUREAU, F.; CHAUVAT, M.; DECAENS, T. |
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Título: |
Mechanisms responsible for diversity-leaf degradation relationship within litter invertebrate experimental assemblages. |
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Ano de publicação: |
2008 |
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Fonte/Imprenta: |
In: INTERNATIONAL COLLOQUIUM ON SOIL ZOOLOGY, 15; INTERNATIONAL COLLOQUIUM ON APTERYGOTA, 12., 2008, Curitiba. Biodiversity, conservation and sustainabele management of soil animal: abstracts. Colombo: Embrapa Florestas. Editors: George Gardner Brown; Klaus Dieter Sautter; Renato Marques; Amarildo Pasini. 1 CD-ROM. |
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Idioma: |
Inglês |
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Conteúdo: |
Despite the great interest concerning the relationship between species diversity and ecosystem
functioning, there low knowledge as to how the diversity of detritivore macro-invertebrate
influences the decomposition of soil organic matter. The aim of this paper was twofold. First,
what is the more relevant measure of diversity to estimate species assemblage effect on a
given function? Second, what are the mechanisms underlying the observed BD-EF patterns?
To answer these questions, we explored the relationship between small experimental
communities of litter macro-detritivore invertebrates and selected indicators of organic matter
degradation.
Four detritivore macro-invertebrate species were selected: a woodlouse (Oniscus asellus), an
earthworm (Dendrodrilus rubidus) and two millipedes (Glomeris marginata and Cylindroiulus
latestriatus). All mixtures from one to four species were made (3 replicates). Invertebrates were
added to microcosms with partially decayed beech leaves. Microcosms were stored for 3 weeks
in climate chambers. Performances on leaf mass loss and C-CO2 release were measured.
Assemblage diversity was measured through (i) species richness (SR), (ii) morphological
dissimilarity (MD) and (iii) functional dissimilarity (FD). Dissimilarities were assessed by
Euclidean distances between species trait coordinates in a multivariate space. Morphological
traits were chosen among morphological attributes related to resource foraging and litter
fragmentation. Functional traits were linked to leaf degradation abilities. The calculation of net
diversity effects and transgressive overyielding allowed discriminating between negative, neutral
and positive interspecific interactions responsible for observed patterns.
Performances of macro-invertebrate assemblages on beech leaf degradation process appeared
to be related to FD rather than to MD or SR. While it has been documented for plant productivity,
only one experiment showed it for soil process. We can advocate that functional equivalence
within mixture of species belonging to a same trophic group limits its performance on leaf
degradation processes. Saturation in process rates occurred after more than SR was greater
than one species which should have reinforced the idea that a significant impact of soil organisms
occurred on decomposition and nutrient cycling at low level of SR, leading to misunderstanding
of BD-EF relationship. Performances of species mixtures were due to negative, neutral or positive
interspecific relationships. Species complementarity explained both leaf mass loss and C
mineralisation performances of D. rubidus-O. asellus and C. latestriatus-O. asellus mixtures.
We can argue that this complementarity was likely to be related to facilitation rather than to
niche differentiation since substrate heterogeneity has been minimized in our experimental
design. Conversely, performances of C. latestriatus-D. rubidus associations were due to neutral
interspecific relationships. This may reveal that these two species fed on different part of decaying
leaves without interactions. Underlying mechanisms of performances for all other mixtures differed
between leaf degradation indicators (leaf mass loss and C-CO2 release). This is consistent
Biodiversity, Conservation and
Sustainable Management of Soil Animals
August 25 - 29, 2008
Positivo University
Curitiba - Paraná - Brazil
with the idea that mechanisms of species performance may differ, for a given mixture, according
to process.
In our work, we used statistics to measure the degree of species dissimilarity instead of grouping
species a priori based on similarity in morphology, life-history, and/or function. Exploring the
BD-EF relationships is related to the question whether equivalence exists between species
performances. This idea is specifically embodied in the concept of ?functional groups?. Our work
and that of others suggests that when we simplify the world by ignoring species identities, that
cost is often too great. MenosDespite the great interest concerning the relationship between species diversity and ecosystem
functioning, there low knowledge as to how the diversity of detritivore macro-invertebrate
influences the decomposition of soil organic matter. The aim of this paper was twofold. First,
what is the more relevant measure of diversity to estimate species assemblage effect on a
given function? Second, what are the mechanisms underlying the observed BD-EF patterns?
To answer these questions, we explored the relationship between small experimental
communities of litter macro-detritivore invertebrates and selected indicators of organic matter
degradation.
Four detritivore macro-invertebrate species were selected: a woodlouse (Oniscus asellus), an
earthworm (Dendrodrilus rubidus) and two millipedes (Glomeris marginata and Cylindroiulus
latestriatus). All mixtures from one to four species were made (3 replicates). Invertebrates were
added to microcosms with partially decayed beech leaves. Microcosms were stored for 3 weeks
in climate chambers. Performances on leaf mass loss and C-CO2 release were measured.
Assemblage diversity was measured through (i) species richness (SR), (ii) morphological
dissimilarity (MD) and (iii) functional dissimilarity (FD). Dissimilarities were assessed by
Euclidean distances between species trait coordinates in a multivariate space. Morphological
traits were chosen among morphological attributes related to resource foraging and litter
fragmentation. Functional ... Mostrar Tudo |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 04745naa a2200157 a 4500
001 1314906
005 2008-09-22
008 2008 bl uuuu u00u1 u #d
100 1 $aHEDDE, M.
245 $aMechanisms responsible for diversity-leaf degradation relationship within litter invertebrate experimental assemblages.
260 $c2008
520 $aDespite the great interest concerning the relationship between species diversity and ecosystem functioning, there low knowledge as to how the diversity of detritivore macro-invertebrate influences the decomposition of soil organic matter. The aim of this paper was twofold. First, what is the more relevant measure of diversity to estimate species assemblage effect on a given function? Second, what are the mechanisms underlying the observed BD-EF patterns? To answer these questions, we explored the relationship between small experimental communities of litter macro-detritivore invertebrates and selected indicators of organic matter degradation. Four detritivore macro-invertebrate species were selected: a woodlouse (Oniscus asellus), an earthworm (Dendrodrilus rubidus) and two millipedes (Glomeris marginata and Cylindroiulus latestriatus). All mixtures from one to four species were made (3 replicates). Invertebrates were added to microcosms with partially decayed beech leaves. Microcosms were stored for 3 weeks in climate chambers. Performances on leaf mass loss and C-CO2 release were measured. Assemblage diversity was measured through (i) species richness (SR), (ii) morphological dissimilarity (MD) and (iii) functional dissimilarity (FD). Dissimilarities were assessed by Euclidean distances between species trait coordinates in a multivariate space. Morphological traits were chosen among morphological attributes related to resource foraging and litter fragmentation. Functional traits were linked to leaf degradation abilities. The calculation of net diversity effects and transgressive overyielding allowed discriminating between negative, neutral and positive interspecific interactions responsible for observed patterns. Performances of macro-invertebrate assemblages on beech leaf degradation process appeared to be related to FD rather than to MD or SR. While it has been documented for plant productivity, only one experiment showed it for soil process. We can advocate that functional equivalence within mixture of species belonging to a same trophic group limits its performance on leaf degradation processes. Saturation in process rates occurred after more than SR was greater than one species which should have reinforced the idea that a significant impact of soil organisms occurred on decomposition and nutrient cycling at low level of SR, leading to misunderstanding of BD-EF relationship. Performances of species mixtures were due to negative, neutral or positive interspecific relationships. Species complementarity explained both leaf mass loss and C mineralisation performances of D. rubidus-O. asellus and C. latestriatus-O. asellus mixtures. We can argue that this complementarity was likely to be related to facilitation rather than to niche differentiation since substrate heterogeneity has been minimized in our experimental design. Conversely, performances of C. latestriatus-D. rubidus associations were due to neutral interspecific relationships. This may reveal that these two species fed on different part of decaying leaves without interactions. Underlying mechanisms of performances for all other mixtures differed between leaf degradation indicators (leaf mass loss and C-CO2 release). This is consistent Biodiversity, Conservation and Sustainable Management of Soil Animals August 25 - 29, 2008 Positivo University Curitiba - Paraná - Brazil with the idea that mechanisms of species performance may differ, for a given mixture, according to process. In our work, we used statistics to measure the degree of species dissimilarity instead of grouping species a priori based on similarity in morphology, life-history, and/or function. Exploring the BD-EF relationships is related to the question whether equivalence exists between species performances. This idea is specifically embodied in the concept of ?functional groups?. Our work and that of others suggests that when we simplify the world by ignoring species identities, that cost is often too great.
700 1 $aBUREAU, F.
700 1 $aCHAUVAT, M.
700 1 $aDECAENS, T.
773 $tIn: INTERNATIONAL COLLOQUIUM ON SOIL ZOOLOGY, 15; INTERNATIONAL COLLOQUIUM ON APTERYGOTA, 12., 2008, Curitiba. Biodiversity, conservation and sustainabele management of soil animal: abstracts. Colombo: Embrapa Florestas. Editors: George Gardner Brown; Klaus Dieter Sautter; Renato Marques; Amarildo Pasini. 1 CD-ROM.
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Embrapa Florestas (CNPF) |
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Biblioteca(s): |
Embrapa Unidades Centrais. |
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Data corrente: |
29/07/2013 |
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Data da última atualização: |
30/07/2013 |
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Autoria: |
SILVA, S. S. da; ARAÚJO NETO, S. E. de. |
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Afiliação: |
SONAIRA SOUZA DA SILVA; SEBASTIÃO ELVIRO DE ARAÚJO NETO. |
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Título: |
Pesquisa-ação na conversão de pastagem em roçado na agricultura familiar amazônica. |
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Ano de publicação: |
2011 |
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Fonte/Imprenta: |
Cadernos de Ciência & Tecnologia, Brasília, DF, v. 28, n. 2, p. 509-529, maio./ago. 2011. |
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Idioma: |
Português |
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Conteúdo: |
Na ausência de ações direcionadas para a sua transferência e adoção, o conhecimento e as tecnologias gerados pela pesquisa científica geralmente se distanciam do processo produtivo, sendo pouco utilizados pelos agricultores, sobretudo na agricultura familiar. Este artigo descreve o processo de transferência dos roçados do fundo do lote para próximo das residências, a transformação de áreas de pastagem de braquiária em roçados e a criação de unidades demonstrativas no assentamento, tendo como base a pesquisa-ação. Uma área de pastagem de braquiária de 20 anos foi gradeada para a semeadura de mucuna-preta (Mucuna aterrima), que, antes da floração, foi roçada, tendo o feijão cv. Rosinha sido semeado a lanço. A experiência de transferir área de pastagem em agricultura e diminuir a distância entre a residência e os roçados foi repetida em 2010 e o será novamente em 2011 pelo mesmo agricultor e por mais seis agricultores do Grupo de Agricultores Ecológicos do Humaitá, no Município de Porto Acre, AC. Nessa área, após a colheita do feijão, foi introduzido cultivo de banana. Essa ação serviu como unidade demonstrativa para intercâmbio com vários grupos de agricultores, técnicos e estudantes. A produtividade do feijoeiro cv. Rosinha foi de 621 kg ha-1, constituindo alternativa tecnológica para áreas de pastagem com baixa produtividade. |
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Thesagro: |
Adubo verde; Agricultura familiar; Pastagem. |
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Thesaurus NAL: |
Family farms; Green manures; Pastures. |
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Categoria do assunto: |
-- |
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URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/86719/1/pesquisa-acao-na-conversao-de-pastagem.pdf
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Marc: |
LEADER 02034naa a2200205 a 4500
001 1962967
005 2013-07-30
008 2011 bl uuuu u00u1 u #d
100 1 $aSILVA, S. S. da
245 $aPesquisa-ação na conversão de pastagem em roçado na agricultura familiar amazônica.$h[electronic resource]
260 $c2011
520 $aNa ausência de ações direcionadas para a sua transferência e adoção, o conhecimento e as tecnologias gerados pela pesquisa científica geralmente se distanciam do processo produtivo, sendo pouco utilizados pelos agricultores, sobretudo na agricultura familiar. Este artigo descreve o processo de transferência dos roçados do fundo do lote para próximo das residências, a transformação de áreas de pastagem de braquiária em roçados e a criação de unidades demonstrativas no assentamento, tendo como base a pesquisa-ação. Uma área de pastagem de braquiária de 20 anos foi gradeada para a semeadura de mucuna-preta (Mucuna aterrima), que, antes da floração, foi roçada, tendo o feijão cv. Rosinha sido semeado a lanço. A experiência de transferir área de pastagem em agricultura e diminuir a distância entre a residência e os roçados foi repetida em 2010 e o será novamente em 2011 pelo mesmo agricultor e por mais seis agricultores do Grupo de Agricultores Ecológicos do Humaitá, no Município de Porto Acre, AC. Nessa área, após a colheita do feijão, foi introduzido cultivo de banana. Essa ação serviu como unidade demonstrativa para intercâmbio com vários grupos de agricultores, técnicos e estudantes. A produtividade do feijoeiro cv. Rosinha foi de 621 kg ha-1, constituindo alternativa tecnológica para áreas de pastagem com baixa produtividade.
650 $aFamily farms
650 $aGreen manures
650 $aPastures
650 $aAdubo verde
650 $aAgricultura familiar
650 $aPastagem
700 1 $aARAÚJO NETO, S. E. de
773 $tCadernos de Ciência & Tecnologia, Brasília, DF$gv. 28, n. 2, p. 509-529, maio./ago. 2011.
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