| |
|
|
 | Acesso ao texto completo restrito à biblioteca da Embrapa Caprinos e Ovinos. Para informações adicionais entre em contato com cnpc.biblioteca@embrapa.br. |
|
Registro Completo |
|
Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
|
Data corrente: |
01/08/1992 |
|
Data da última atualização: |
24/05/2023 |
|
Autoria: |
PEAKE, D. C. I.; HENZELL, E. F.; STIRK, G. B.; PEAKE, A. |
|
Título: |
Simulation of changes in herbage biomass and drought response of a buffel grass (Cenchrus ciliaris cv. biloela) in Southern Queensland. |
|
Ano de publicação: |
1979 |
|
Fonte/Imprenta: |
Agro-Ecosystems, v. 5, n. 1, p. 23-40, Jan. 1979. |
|
DOI: |
https://doi.org/10.1016/0304-3746(79)90024-6 |
|
Idioma: |
Inglês |
|
Conteúdo: |
Abstract: Changes of herbage biomass on ungrazed Biloela buffel grass swards at the Narayen Research Station were investigated in field experiments and by means of computer simulation. The daily rate of change of herbage biomass was calculated by an empiricial model consisting of two equations. The first, used when the ration of estimated actual to potential transpiration (transpiration ratio) was > 0.26, computed the daily of increase in herbage dry weight (DW) as the product of the potential net production of herbage multiplied by temperature and moisture factors, and by a factor that allowed for delayed regrowth when effective rain fell after drought. The second equation, used when the transpiration ratio was < 0.26, computed the daily loss of DW as a function of the standing weight of herbage multiplied by the same moisture factor. Transpiration was estimated with a water-balance model. The herbage model was used to simulate the biomass of Biloela buffel grass on an ungrazed field experiment on a duplex soil (similar to the solodic and eutric planosols of the ?FAO Soil Map of the World?). The plots were mown three times a year, in spring, summer and autumn, and they received sufficient nitrogen and other nutrients for near-maximum production. The linear regression of measured on simulated DW's of herbage for the two years' data from which the values of the models' constants and functions were derived had a coefficient of determination (R2) of 0.955; two additional years' results from the same experiment were estimated with an R2 of 0.913. Using the same model but different soil constants, in another experiment at Narayen on a gradational clay soil (related to the eutric nitosols) the biomass of Biloela buffel grass was simulated with an R2 of 0.823. The model was then used with historical rainfall records to simulate the biomass of Biloela buffell grass herbage in the Narayen environment for the period 1887 to 1973. Frequencies were calculated for: (a) in the case of swards with optimum nitrogen supply ? estimated mean daily transpiration ratios, estimated daily rates of herbage production (or reduction), and estimated herbage yields from three harvests a year, and (b) in the case of swards dependent on soil nitrogen ? potential nitrogen fertilizer responses of at least 200 or 2000 kg DW ha?1 at the spring, summer and autumn harvests. The reduction in standing crop of herbage during drought, delay in regrowth after drought, evapotranspiration models, and nitrogen responses in dry climates are discussed with reference to previous results. MenosAbstract: Changes of herbage biomass on ungrazed Biloela buffel grass swards at the Narayen Research Station were investigated in field experiments and by means of computer simulation. The daily rate of change of herbage biomass was calculated by an empiricial model consisting of two equations. The first, used when the ration of estimated actual to potential transpiration (transpiration ratio) was > 0.26, computed the daily of increase in herbage dry weight (DW) as the product of the potential net production of herbage multiplied by temperature and moisture factors, and by a factor that allowed for delayed regrowth when effective rain fell after drought. The second equation, used when the transpiration ratio was < 0.26, computed the daily loss of DW as a function of the standing weight of herbage multiplied by the same moisture factor. Transpiration was estimated with a water-balance model. The herbage model was used to simulate the biomass of Biloela buffel grass on an ungrazed field experiment on a duplex soil (similar to the solodic and eutric planosols of the ?FAO Soil Map of the World?). The plots were mown three times a year, in spring, summer and autumn, and they received sufficient nitrogen and other nutrients for near-maximum production. The linear regression of measured on simulated DW's of herbage for the two years' data from which the values of the models' constants and functions were derived had a coefficient of determination (R2) of 0.955; two additional years'... Mostrar Tudo |
|
Palavras-Chave: |
Weights. |
|
Thesagro: |
Capim Buffel; Cenchrus ciliaris; Gramínea; Planta Forrageira. |
|
Thesaurus Nal: |
Australia; Biomass; Forage grasses; Growing season; Vegetable growing. |
|
Categoria do assunto: |
L Ciência Animal e Produtos de Origem Animal |
|
Marc: |
LEADER 03469naa a2200289 a 4500
001 1523785
005 2023-05-24
008 1979 bl uuuu u00u1 u #d
024 7 $ahttps://doi.org/10.1016/0304-3746(79)90024-6$2DOI
100 1 $aPEAKE, D. C. I.
245 $aSimulation of changes in herbage biomass and drought response of a buffel grass (Cenchrus ciliaris cv. biloela) in Southern Queensland.$h[electronic resource]
260 $c1979
520 $aAbstract: Changes of herbage biomass on ungrazed Biloela buffel grass swards at the Narayen Research Station were investigated in field experiments and by means of computer simulation. The daily rate of change of herbage biomass was calculated by an empiricial model consisting of two equations. The first, used when the ration of estimated actual to potential transpiration (transpiration ratio) was > 0.26, computed the daily of increase in herbage dry weight (DW) as the product of the potential net production of herbage multiplied by temperature and moisture factors, and by a factor that allowed for delayed regrowth when effective rain fell after drought. The second equation, used when the transpiration ratio was < 0.26, computed the daily loss of DW as a function of the standing weight of herbage multiplied by the same moisture factor. Transpiration was estimated with a water-balance model. The herbage model was used to simulate the biomass of Biloela buffel grass on an ungrazed field experiment on a duplex soil (similar to the solodic and eutric planosols of the ?FAO Soil Map of the World?). The plots were mown three times a year, in spring, summer and autumn, and they received sufficient nitrogen and other nutrients for near-maximum production. The linear regression of measured on simulated DW's of herbage for the two years' data from which the values of the models' constants and functions were derived had a coefficient of determination (R2) of 0.955; two additional years' results from the same experiment were estimated with an R2 of 0.913. Using the same model but different soil constants, in another experiment at Narayen on a gradational clay soil (related to the eutric nitosols) the biomass of Biloela buffel grass was simulated with an R2 of 0.823. The model was then used with historical rainfall records to simulate the biomass of Biloela buffell grass herbage in the Narayen environment for the period 1887 to 1973. Frequencies were calculated for: (a) in the case of swards with optimum nitrogen supply ? estimated mean daily transpiration ratios, estimated daily rates of herbage production (or reduction), and estimated herbage yields from three harvests a year, and (b) in the case of swards dependent on soil nitrogen ? potential nitrogen fertilizer responses of at least 200 or 2000 kg DW ha?1 at the spring, summer and autumn harvests. The reduction in standing crop of herbage during drought, delay in regrowth after drought, evapotranspiration models, and nitrogen responses in dry climates are discussed with reference to previous results.
650 $aAustralia
650 $aBiomass
650 $aForage grasses
650 $aGrowing season
650 $aVegetable growing
650 $aCapim Buffel
650 $aCenchrus ciliaris
650 $aGramínea
650 $aPlanta Forrageira
653 $aWeights
700 1 $aHENZELL, E. F.
700 1 $aSTIRK, G. B.
700 1 $aPEAKE, A.
773 $tAgro-Ecosystems$gv. 5, n. 1, p. 23-40, Jan. 1979.
Download
Esconder MarcMostrar Marc Completo |
|
Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
|
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
URL |
Voltar
|
|
|
| Registros recuperados : 1 | |
| 1. |  | SCARPARE FILHO, J. A.; KLUGE, R. A.; VICTORIA FILHO, R.; TESSARIOLI NETO, J. A.; JACOMINO, P. Comportamento de duas cultivares de pessegueiro com interenxerto da ameixeira Januária. Pesquisa Agropecuária Brasileira, Brasília, DF, v. 35, n. 4, p. 757-765, abr. 2000. Título em inglês: Behavior of two peach cultivars with 'Januária' as a Japanese plum interstock.| Biblioteca(s): Embrapa Unidades Centrais. |
|    |
| Registros recuperados : 1 | |
|
| Nenhum registro encontrado para a expressão de busca informada. |
|
|
