|
|
Registro Completo |
Biblioteca(s): |
Embrapa Meio-Norte. |
Data corrente: |
14/10/1996 |
Data da última atualização: |
14/10/1996 |
Autoria: |
SILVA, V. V. da; KHAN, A. S.; RAMOS, G. M. |
Afiliação: |
EMBRAPA-UEPAE de Teresina. |
Título: |
Determinaco do periodo otimo de pastejo de bovinos de corte no estado do Piaui. |
Ano de publicação: |
1984 |
Fonte/Imprenta: |
In. CONGRESSO BRASILEIRO DE ECONOMIA E SOCIOLOGIA RURAL, 22., 1984, Salvador. Anais... Salvador, SOBER, 1984. p. 82-86. |
Volume: |
v.3 |
Idioma: |
Português |
Conteúdo: |
O estudo procurou analisar a viabilidade economica da exploracao de bovinos de corte em pastagem nativa adubada e submetida a diferentes taxas de lotacao. Neste sentido, foram determinados o periodo de tempo otimo de pastejo dos animais e o maximo valor presente da receita liquida por animal no periodo otimo de pastejo. |
Palavras-Chave: |
Bovino de corte; Brasil; Catle; Piaui; Viabilidade economica. |
Thesagro: |
Adubação; Pastagem Nativa; Pastejo. |
Categoria do assunto: |
-- |
Marc: |
LEADER 01062naa a2200265 a 4500 001 1054296 005 1996-10-14 008 1984 bl uuuu u00u1 u #d 100 1 $aSILVA, V. V. da 245 $aDeterminaco do periodo otimo de pastejo de bovinos de corte no estado do Piaui. 260 $c1984 300 $av.3 490 $vv.3 520 $aO estudo procurou analisar a viabilidade economica da exploracao de bovinos de corte em pastagem nativa adubada e submetida a diferentes taxas de lotacao. Neste sentido, foram determinados o periodo de tempo otimo de pastejo dos animais e o maximo valor presente da receita liquida por animal no periodo otimo de pastejo. 650 $aAdubação 650 $aPastagem Nativa 650 $aPastejo 653 $aBovino de corte 653 $aBrasil 653 $aCatle 653 $aPiaui 653 $aViabilidade economica 700 1 $aKHAN, A. S. 700 1 $aRAMOS, G. M. 773 $tIn. CONGRESSO BRASILEIRO DE ECONOMIA E SOCIOLOGIA RURAL, 22., 1984, Salvador. Anais... Salvador, SOBER, 1984. p. 82-86.
Download
Esconder MarcMostrar Marc Completo |
Registro original: |
Embrapa Meio-Norte (CPAMN) |
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
URL |
Voltar
|
|
Registro Completo
Biblioteca(s): |
Embrapa Amazônia Oriental. |
Data corrente: |
08/10/2021 |
Data da última atualização: |
13/10/2021 |
Tipo da produção científica: |
Artigo em Periódico Indexado |
Circulação/Nível: |
A - 2 |
Autoria: |
TAYLOR, T. C.; WISNIEWSKI, W. T.; ALVES, E. G.; OLIVEIRA JUNIOR, R. C. de; SALESKA, S. R. |
Afiliação: |
TYEEN C. TAYLOR, University of Arizona / University of Miami; WIT T. WISNIEWSKI, University of Arizona; ELIANE G. ALVES, Max Planck Institute for Biogeochemistry; RAIMUNDO COSME DE OLIVEIRA JUNIOR, CPATU; SCOTT R. SALESKA, University of Arizona. |
Título: |
A new field instrument for leaf volatiles reveals an unexpected vertical profile of isoprenoid emission capacities in a tropical forest. |
Ano de publicação: |
2021 |
Fonte/Imprenta: |
Frontiers in Forests and Global Change, v. 4, article 668228, July 2021. |
DOI: |
10.3389/ffgc.2021.668228 |
Idioma: |
Inglês |
Conteúdo: |
Both plant physiology and atmospheric chemistry are substantially altered by the emission of volatile isoprenoids (VI), such as isoprene and monoterpenes, from plant leaves. Yet, since gaining scientific attention in the 1950?s, empirical research on leaf VI has been largely confined to laboratory experiments and atmospheric observations. Here, we introduce a new field instrument designed to bridge the scales from leaf to atmosphere, by enabling precision VI detection in real time from plants in their natural ecological setting. With a field campaign in the Brazilian Amazon, we reveal an unexpected distribution of leaf emission capacities (EC) across the vertical axis of the forest canopy, with EC peaking in the mid-canopy instead of the sun-exposed canopy surface, and moderately high emissions occurring in understory specialist species. Compared to the simple interpretation that VI protect leaves from heat stress at the hot canopy surface, our results encourage a more nuanced view of the adaptive role of VI in plants. We infer that forest emissions to the atmosphere depend on the dynamic microenvironments imposed by canopy structure, and not simply on canopy surface conditions. We provide a new emissions inventory from 52 tropical tree species, revealing moderate consistency in EC within taxonomic groups. We highlight priorities in leaf volatiles research that require field-portable detection systems. Our self-contained, portable instrument provides real-time detection and live measurement feedback with precision and detection limits better than 0.5 nmolVI m-2 leaf s-1. We call the instrument ?PORCO? based on the gas detection method: photoionization of organic compounds. We provide a thorough validation of PORCO and demonstrate its capacity to detect ecologically driven variation in leaf emission rates and thus accelerate a nascent field of science: the ecology and ecophysiology of plant volatiles. MenosBoth plant physiology and atmospheric chemistry are substantially altered by the emission of volatile isoprenoids (VI), such as isoprene and monoterpenes, from plant leaves. Yet, since gaining scientific attention in the 1950?s, empirical research on leaf VI has been largely confined to laboratory experiments and atmospheric observations. Here, we introduce a new field instrument designed to bridge the scales from leaf to atmosphere, by enabling precision VI detection in real time from plants in their natural ecological setting. With a field campaign in the Brazilian Amazon, we reveal an unexpected distribution of leaf emission capacities (EC) across the vertical axis of the forest canopy, with EC peaking in the mid-canopy instead of the sun-exposed canopy surface, and moderately high emissions occurring in understory specialist species. Compared to the simple interpretation that VI protect leaves from heat stress at the hot canopy surface, our results encourage a more nuanced view of the adaptive role of VI in plants. We infer that forest emissions to the atmosphere depend on the dynamic microenvironments imposed by canopy structure, and not simply on canopy surface conditions. We provide a new emissions inventory from 52 tropical tree species, revealing moderate consistency in EC within taxonomic groups. We highlight priorities in leaf volatiles research that require field-portable detection systems. Our self-contained, portable instrument provides real-time detection and ... Mostrar Tudo |
Palavras-Chave: |
Ecofisiologia; Estrutura florestal; Microambiente; Química atmosférica. |
Thesagro: |
Floresta Tropical. |
Categoria do assunto: |
K Ciência Florestal e Produtos de Origem Vegetal |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/226815/1/ffgc-04-6682281.pdf
|
Marc: |
LEADER 02738naa a2200241 a 4500 001 2135178 005 2021-10-13 008 2021 bl uuuu u00u1 u #d 024 7 $a10.3389/ffgc.2021.668228$2DOI 100 1 $aTAYLOR, T. C. 245 $aA new field instrument for leaf volatiles reveals an unexpected vertical profile of isoprenoid emission capacities in a tropical forest.$h[electronic resource] 260 $c2021 520 $aBoth plant physiology and atmospheric chemistry are substantially altered by the emission of volatile isoprenoids (VI), such as isoprene and monoterpenes, from plant leaves. Yet, since gaining scientific attention in the 1950?s, empirical research on leaf VI has been largely confined to laboratory experiments and atmospheric observations. Here, we introduce a new field instrument designed to bridge the scales from leaf to atmosphere, by enabling precision VI detection in real time from plants in their natural ecological setting. With a field campaign in the Brazilian Amazon, we reveal an unexpected distribution of leaf emission capacities (EC) across the vertical axis of the forest canopy, with EC peaking in the mid-canopy instead of the sun-exposed canopy surface, and moderately high emissions occurring in understory specialist species. Compared to the simple interpretation that VI protect leaves from heat stress at the hot canopy surface, our results encourage a more nuanced view of the adaptive role of VI in plants. We infer that forest emissions to the atmosphere depend on the dynamic microenvironments imposed by canopy structure, and not simply on canopy surface conditions. We provide a new emissions inventory from 52 tropical tree species, revealing moderate consistency in EC within taxonomic groups. We highlight priorities in leaf volatiles research that require field-portable detection systems. Our self-contained, portable instrument provides real-time detection and live measurement feedback with precision and detection limits better than 0.5 nmolVI m-2 leaf s-1. We call the instrument ?PORCO? based on the gas detection method: photoionization of organic compounds. We provide a thorough validation of PORCO and demonstrate its capacity to detect ecologically driven variation in leaf emission rates and thus accelerate a nascent field of science: the ecology and ecophysiology of plant volatiles. 650 $aFloresta Tropical 653 $aEcofisiologia 653 $aEstrutura florestal 653 $aMicroambiente 653 $aQuímica atmosférica 700 1 $aWISNIEWSKI, W. T. 700 1 $aALVES, E. G. 700 1 $aOLIVEIRA JUNIOR, R. C. de 700 1 $aSALESKA, S. R. 773 $tFrontiers in Forests and Global Change$gv. 4, article 668228, July 2021.
Download
Esconder MarcMostrar Marc Completo |
Registro original: |
Embrapa Amazônia Oriental (CPATU) |
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
Fechar
|
Nenhum registro encontrado para a expressão de busca informada. |
|
|