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1.
Int J Environ Sci Technol (Tehran) ; 20(5): 5471-5490, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36213697

RESUMO

We aimed to map and analyze LAI by using Landsat 8 and Sentinel-2 time series and the corresponding ground measurements collected in pure Anatolian black pine [Pinus nigra J.F. Arnold ssp. pallasiana (Lamb.) Holmboe] stands within seven-month (from June to December) period. A total of 30 sample plots were selected and seven-month changes of LAI values were determined through hemispherical photography for each sample plot. Remote sensing (reflectance values and vegetation indices obtained from Landsat-8 and Sentinel-2) and topographic (elevation, aspect, and slope) data were used to model the LAI for each month using multiple linear regression (MLR) method. Additionally, the data for all months were combined and modeled. In this case, autoregressive modeling techniques were used to solve the temporal autocorrelation problem. Our study indicated that the models developed from Sentinel-2 give more successful results than Landsat 8 on monthly LAI models. The most successful models were obtained in June by using the reflectance values (Radj2 = 0.39, RMSE = 0.3138 m2 m-2), reflectance values-topographic data (Radj2 = 0.59, RMSE = 0.3174 m2 m-2), vegetation indices-topographic data (Radj2 = 0.82, RMSE = 0.2126 m2 m-2), and reflectance values-vegetation indices-topographic data (Radj2 = 0.93, RMSE = 0.1060 m2 m-2). Among the autoregressive modeling techniques, the highest success was obtained with the Landsat 8 OLI using the moving average (2) procedure (R2 = 0.56). This study is significant that it is the first to analyze the monthly effect on LAI modeling and mapping in pure Anatolian black pine stands using both reflectance values, vegetation indices, and topographic data.

2.
Poult Sci ; 88(6): 1330-3, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19439647

RESUMO

The effect of 1 to 2-, 3 to 4-, 5 to 6-, 7 to 8-, 9 to 10-, 11 to 12-, and 13 to 14-d storage periods on quality characteristics and hatchability of partridge (Alectoris graeca) eggs was studied. There was no significant effect of storage period on egg weight, shell weight, shell ratio, and shell thickness as external quality characteristics of partridge eggs (P > 0.05). Storage periods affected internal quality characteristics of partridge eggs (P < 0.05). An increase in yolk ratio (P < 0.05) and decrease in albumen ratio, yolk index, albumen index, and Haugh unit (P < 0.001) occurred when storage periods were lengthened. However, storage period had no significant effect on hatchability (P > 0.05). This study shows that long storage periods do not have negative effects on hatchability of partridge eggs to the extent that occurs in other poultry species. Because of a lack of knowledge about this subject, these studies will be useful in terms of successful intensive partridge breeding.


Assuntos
Ovos , Galliformes , Albuminas , Criação de Animais Domésticos/métodos , Animais , Casca de Ovo , Feminino , Masculino , Fatores de Tempo
3.
Poult Sci ; 86(8): 1800-4, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17626827

RESUMO

In this study, stocking density and economic evaluation of partridge rearing was investigated. Experimental design was constructed as 576.9 cm(2)/chick (group I), 384.6 cm(2)/chick (group II), 288.5 cm(2)/chick (group III), and 230.8 cm(2)/chick (group IV). Live weights of the first, second, third, and fourth groups at 12 wk of age were determined as 376.46, 367.95, 371.07, and 358.80 g, respectively. Additive feed consumption and feed conversion ratio of the groups were determined as 1,781.74 g and 4.93, 1,805.13 g and 5.13, 1,830.51 g and 5.15, and 1,720.09 g and 5.02, respectively. Total mortality rates of the groups at the end of the feeding time were determined as 3.5, 3.75, 6.75, and 13.00%, respectively (P < 0.05). As a result, it was concluded that rearing in 288.5 cm(2)/chick was suitable according to live weights of partridges, feed conversion ratio, and mortality rates. Also, it was concluded that decreasing costs and increasing profitability in partridge rearing could be achieved.


Assuntos
Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Galliformes/crescimento & desenvolvimento , Abrigo para Animais , Animais
4.
Poult Sci ; 86(7): 1380-3, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17575185

RESUMO

A study was conducted to determine the effect of live weight of partridges on egg production and egg quality characteristics. A total of 144 Rock Partridges were divided into control, heavy, middle, and light BW groups at 32 wk of age. Live weights averaged 512.78 g for the control group, 576.18 g for the heavy group, 523.49 g for the middle group, and 473.83 g for the light group. Egg production rates of these groups were 41.44, 45.78, 32.38, and 24.67%, respectively, over an 8-wk period (P < 0.05). Live weight significantly affected egg weight, specific gravity, albumen index, shell weight, shell thickness, Haugh unit, and albumen weight (P < 0.05). Live weight did not affect the shape index, membrane weight, or yolk weight. As a result, the live weights of partridges used for breeding should not be under the average live weights of hens of the stock. On the other hand, other important factors that affect the egg quality of partridges should be investigated.


Assuntos
Peso Corporal/fisiologia , Galliformes/fisiologia , Oviposição/fisiologia , Óvulo/fisiologia , Animais , Feminino
5.
Br Poult Sci ; 45(3): 380-4, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15327124

RESUMO

1. The effects of initial egg mass (IEM) and percentage mass loss during incubation (%ML) on hatchability of rock partridge eggs were investigated. 2. Eggs at the extremes of IEM had lower fertility and embryonic mortality. 3. Eggs at the extremes of %ML also had low fertility and hatchability was disproportionately reduced in eggs that had lost less mass during incubation. 4. Chick mass was a function of both IEM and mass lost during incubation. 5. In these respects rock partridge eggs are similar to that of other domesticated species of poultry.


Assuntos
Embrião não Mamífero/fisiologia , Aves Domésticas/embriologia , Aves Domésticas/fisiologia , Animais , Cruzamento , Fertilidade , Análise de Regressão
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