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Registro Completo |
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Biblioteca(s): |
Embrapa Unidades Centrais. |
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Data corrente: |
25/03/2002 |
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Data da última atualização: |
03/04/2017 |
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Autoria: |
CARVALHO, M. A. de; FREIRE, J. C.; CURI, N.; BAHIA, V. G. |
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Afiliação: |
MARCO ANTÔNIO DE CARVALHO, EPAMIG; JEZIEL CARDOSO FREIRE; NILTON CURI, UFLA; VICTOR GONÇAVES BAHIA, UFLA. |
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Título: |
Eficiência de dispersantes na análise granulométrica de materiais de solos com horizonte B textural. |
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Ano de publicação: |
1988 |
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Fonte/Imprenta: |
Pesquisa Agropecuária Brasileira, Brasília, DF, v. 23, n. 4, p. 415-421, abr. 1988. |
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Idioma: |
Português |
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Conteúdo: |
A eficiência de dispersantes na análise granulométrica foi estudada em nove diferentes materiais de solos com horizonte B textural. Foram utilizados, o hidróxido de sódio, hexametafosfato de sódio e hexametafosfato de sódio + carbonato de sódio como dispersantes químicos, com agitações rápida e lenta, na presença e ausência de agente abrasivo. A eficiência dos dispersantes foi avaliada através da percentagcm de argila, que foi determinada pelos métodos da pipeta c do hidrômetro. Os resultados evidenciaram que a presença de areia grossa como agente abrasivo na desagregação mostrou-se eficiente, como também a agitação lenta, principalmente quando associada com o agente abrasivo. Dos métodos utilizados na determinação de argila, o da pipeta foi o que apresentou maior eficiência. 0 hidróxido de sódio e o hexametafosfato de sódio tiveram ação dispersante semelhante para esses pedomateriais. |
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Palavras-Chave: |
Abrasive agent; agente abrasivo; pipeta; Pipette. |
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Thesagro: |
Argila; Hidrômetro; Hidróxido de sódio. |
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Thesaurus Nal: |
Clay; Hydrometers; Sodium hydroxide. |
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Categoria do assunto: |
-- |
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URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/158507/1/Eficiencia-de-dispersantes-na-analise.pdf
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Marc: |
LEADER 01712naa a2200277 a 4500
001 1106729
005 2017-04-03
008 1988 bl uuuu u00u1 u #d
100 1 $aCARVALHO, M. A. de
245 $aEficiência de dispersantes na análise granulométrica de materiais de solos com horizonte B textural.
260 $c1988
520 $aA eficiência de dispersantes na análise granulométrica foi estudada em nove diferentes materiais de solos com horizonte B textural. Foram utilizados, o hidróxido de sódio, hexametafosfato de sódio e hexametafosfato de sódio + carbonato de sódio como dispersantes químicos, com agitações rápida e lenta, na presença e ausência de agente abrasivo. A eficiência dos dispersantes foi avaliada através da percentagcm de argila, que foi determinada pelos métodos da pipeta c do hidrômetro. Os resultados evidenciaram que a presença de areia grossa como agente abrasivo na desagregação mostrou-se eficiente, como também a agitação lenta, principalmente quando associada com o agente abrasivo. Dos métodos utilizados na determinação de argila, o da pipeta foi o que apresentou maior eficiência. 0 hidróxido de sódio e o hexametafosfato de sódio tiveram ação dispersante semelhante para esses pedomateriais.
650 $aClay
650 $aHydrometers
650 $aSodium hydroxide
650 $aArgila
650 $aHidrômetro
650 $aHidróxido de sódio
653 $aAbrasive agent
653 $aagente abrasivo
653 $apipeta
653 $aPipette
700 1 $aFREIRE, J. C.
700 1 $aCURI, N.
700 1 $aBAHIA, V. G.
773 $tPesquisa Agropecuária Brasileira, Brasília, DF$gv. 23, n. 4, p. 415-421, abr. 1988.
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Embrapa Unidades Centrais (AI-SEDE) |
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Biblioteca(s): |
Embrapa Amapá. |
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Data corrente: |
15/12/2020 |
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Data da última atualização: |
31/03/2021 |
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Tipo da produção científica: |
Artigo em Periódico Indexado |
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Circulação/Nível: |
A - 2 |
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Autoria: |
LIMA, R. B. de; RUTISHAUSER, E.; SILVA, J. A. A. da; GUEDES, M. C.; HERAULT, B.; OLIVEIRA, C. P. de; APARÍCIO, P. da S.; SOTTA, E. D.; SILVA, D. A. S. da; FERREIRA, R. L. C. |
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Afiliação: |
ROBSON BORGES DE LIMA, UEAP; ERVAN RUTISHAUSER, SMITHSONIAN TROPICAL RESEARCH INSTITUTE; JOSÉ ANTÔNIO ALEIXO DA SILVA, UFRPE; MARCELINO CARNEIRO GUEDES, CPAF-AP; BRUNO HERAULT, CIRAD; CINTHIA PEREIRA DE OLIVEIRA, UEAP; PERSEU DA SILVA APARÍCIO, UEAP; ELENEIDE DOFF SOTTA, CPAF-AP; DIEGO ARMANDO SILVA DA SILVA, IFAP; RINALDO LUIZ CARACIOLO FERREIRA, UFRPE. |
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Título: |
Accurate estimation of commercial volume in tropical forests. |
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Ano de publicação: |
2020 |
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Fonte/Imprenta: |
Forest Science, p. 1-8, July 2020. |
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DOI: |
10.1093/forsci/fxaa032 |
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Idioma: |
Inglês |
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Conteúdo: |
Accurate estimates of commercial volume in tropical forests are key for the implementation of sustainable forest management plans. Because of the lack of local or generic volumetric equations, most forest managers and forestry services are still using traditional expansion factors (i.e., multiplication of the diameter by a given value) to estimate the volume of commercial tree species in the Amazon. Volumetric models were developed through a unique data set of 1,264 fallen trees fully measured in 150 sample plots located across a broad range of forests in Amapá, Brazil. Forest-specific volumetric models were developed and compared with a generic (i.e., across all forests) model and with published equations developed elsewhere in the Amazon. The generic equation performed well in all forest types and allowed precise predictions. The most efficient sampling design to develop volumetric models consists of measuring approximately 50 trees across four different size classes representing the whole population. The form factors (FF) developed locally generated substantial bias but performed better than the traditional FF (0.7). Overall, our results suggest that it is possible to develop accurate generic models to estimate commercial timber volume, and this study can serve as a guideline for forest managers or scientists interested in calibrating volumetric models in a cost-efficient way. Study Implications: This work provides useful information on volumetric modeling methods for Brazilian Amazon tropical forests. Most of the studies in the literature only investigate the classical modeling using regression models considering only boom metrics with or without bark, and, in this way, they provide incomplete and biased total knowledge and estimates for a given population. Therefore, detailed and accurate analyzes are crucial tools for decisionmaking. If the harvesting interventions are carried out without considering the most appropriate method to estimate the total wood stock, there may be damages or even extinction of some species, as has happened with other forest domains in Brazil and in other rainforest regions in the world. In this work, the results clearly show the importance of testing different methodologies and selecting the one best suited for a particular site, as well as carrying out techniques for the sustainable and correct management of the forest. Because the analysis procedures provide only information on how methodologies behave statistically, our results may contribute to a more refined analysis to be applied in the future in similar environments. Currently, the Brazilian forestry sector is looking for alternatives to obtain forest resources within the concept of sustainability. For the Brazilian Amazon tropical forest domain, it is extremely important to achieve a sustainable management of resources through forest management. Most studies in the literature investigate the management of tropical rainforest, whereas there is a lack of scientific information on the transition range for the cerrado. MenosAccurate estimates of commercial volume in tropical forests are key for the implementation of sustainable forest management plans. Because of the lack of local or generic volumetric equations, most forest managers and forestry services are still using traditional expansion factors (i.e., multiplication of the diameter by a given value) to estimate the volume of commercial tree species in the Amazon. Volumetric models were developed through a unique data set of 1,264 fallen trees fully measured in 150 sample plots located across a broad range of forests in Amapá, Brazil. Forest-specific volumetric models were developed and compared with a generic (i.e., across all forests) model and with published equations developed elsewhere in the Amazon. The generic equation performed well in all forest types and allowed precise predictions. The most efficient sampling design to develop volumetric models consists of measuring approximately 50 trees across four different size classes representing the whole population. The form factors (FF) developed locally generated substantial bias but performed better than the traditional FF (0.7). Overall, our results suggest that it is possible to develop accurate generic models to estimate commercial timber volume, and this study can serve as a guideline for forest managers or scientists interested in calibrating volumetric models in a cost-efficient way. Study Implications: This work provides useful information on volumetric modeling methods for Bra... Mostrar Tudo |
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Palavras-Chave: |
Brazilian Amazonia; Form factor; Generic equations; Manejo florestal. |
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Thesagro: |
Floresta Tropical. |
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Thesaurus NAL: |
Forest management. |
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Categoria do assunto: |
K Ciência Florestal e Produtos de Origem Vegetal |
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URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/219251/1/CPAF-AP-2020-Accurate-estimation-of-commercial.pdf
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Marc: |
LEADER 03941naa a2200313 a 4500
001 2128189
005 2021-03-31
008 2020 bl uuuu u00u1 u #d
024 7 $a10.1093/forsci/fxaa032$2DOI
100 1 $aLIMA, R. B. de
245 $aAccurate estimation of commercial volume in tropical forests.$h[electronic resource]
260 $c2020
520 $aAccurate estimates of commercial volume in tropical forests are key for the implementation of sustainable forest management plans. Because of the lack of local or generic volumetric equations, most forest managers and forestry services are still using traditional expansion factors (i.e., multiplication of the diameter by a given value) to estimate the volume of commercial tree species in the Amazon. Volumetric models were developed through a unique data set of 1,264 fallen trees fully measured in 150 sample plots located across a broad range of forests in Amapá, Brazil. Forest-specific volumetric models were developed and compared with a generic (i.e., across all forests) model and with published equations developed elsewhere in the Amazon. The generic equation performed well in all forest types and allowed precise predictions. The most efficient sampling design to develop volumetric models consists of measuring approximately 50 trees across four different size classes representing the whole population. The form factors (FF) developed locally generated substantial bias but performed better than the traditional FF (0.7). Overall, our results suggest that it is possible to develop accurate generic models to estimate commercial timber volume, and this study can serve as a guideline for forest managers or scientists interested in calibrating volumetric models in a cost-efficient way. Study Implications: This work provides useful information on volumetric modeling methods for Brazilian Amazon tropical forests. Most of the studies in the literature only investigate the classical modeling using regression models considering only boom metrics with or without bark, and, in this way, they provide incomplete and biased total knowledge and estimates for a given population. Therefore, detailed and accurate analyzes are crucial tools for decisionmaking. If the harvesting interventions are carried out without considering the most appropriate method to estimate the total wood stock, there may be damages or even extinction of some species, as has happened with other forest domains in Brazil and in other rainforest regions in the world. In this work, the results clearly show the importance of testing different methodologies and selecting the one best suited for a particular site, as well as carrying out techniques for the sustainable and correct management of the forest. Because the analysis procedures provide only information on how methodologies behave statistically, our results may contribute to a more refined analysis to be applied in the future in similar environments. Currently, the Brazilian forestry sector is looking for alternatives to obtain forest resources within the concept of sustainability. For the Brazilian Amazon tropical forest domain, it is extremely important to achieve a sustainable management of resources through forest management. Most studies in the literature investigate the management of tropical rainforest, whereas there is a lack of scientific information on the transition range for the cerrado.
650 $aForest management
650 $aFloresta Tropical
653 $aBrazilian Amazonia
653 $aForm factor
653 $aGeneric equations
653 $aManejo florestal
700 1 $aRUTISHAUSER, E.
700 1 $aSILVA, J. A. A. da
700 1 $aGUEDES, M. C.
700 1 $aHERAULT, B.
700 1 $aOLIVEIRA, C. P. de
700 1 $aAPARÍCIO, P. da S.
700 1 $aSOTTA, E. D.
700 1 $aSILVA, D. A. S. da
700 1 $aFERREIRA, R. L. C.
773 $tForest Science, p. 1-8, July 2020.
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