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Solaimani K.,Sari University of Agriculture and Natural Resources
International Journal of Fluid Mechanics Research | Year: 2011

Flood plains and the area near to the rivers channels, because of their special circumstances such as fertility and water resources are appropriate situations for the social and agricultural activities, but due to morphological characteristics usually, these area are affected by different flood hazards. Interaction between some river hydrologic models and geographical information systems (GIS) cause some gains and methods, which are reasonable to the planners. This study was carried out with the purpose of using hydraulic model of HEC-RAS with Arc View software to estimate the flood zone of 5 km distance on Neka River in Northern part of Iran, where during the last decade we had different flood events with a high magnitude damages. Topography maps at 1:1000 scales were used for the flood zonation for different periods of 2, 5, 10, 25, 50, 100, and 200 years. The results obtained attest to the fact that the combination of GIS and HEC-RAS model used in this study is useful and efficient in delineating the flood zonation. Finally the flood zone of 25 years is predicted to be more hazardous than the other periods for the selected areas. © 2011 Begell House, Inc.

Gholami L.,Sari University of Agriculture and Natural Resources | Banasik K.,Warsaw University of Life Sciences | Sadeghi S.H.,Tarbiat Modares University | Khaledi Darvishan A.,Tarbiat Modares University | Hejduk L.,Warsaw University of Life Sciences
Journal of Water and Land Development | Year: 2014

Mulches have extraordinary potential in reducing surface runoff, increasing infiltration of water into the soil and decreasing soil erosion. The straw mulches as a biological material, has the ability to be a significant physical barrier against the impact of raindrops and reduce the detachment of soil aggregates. The present study is an attempt to determine the efficiency of straw mulch as conservation treatment in changes in the splash erosion, time-to-runoff, runoff coefficient, infiltration coefficient, time-to-drainage, drainage coefficient, sediment concentration and soil loss. The laboratory experiments have been conducted for sandy-loam soil taken from deforested area, about 15 km of Warsaw west, Poland under lab conditions with simulated rainfall intensities of 60 and 120 mmh-1, in 4 soil moistures of 12, 25, 33 and 40% and the slope of 9%. Compared with bare treatments, results of straw mulch application showed the significant conservation effects on splash erosion, runoff coefficient, sediment concentration and soil loss and significant enhancement effects on infiltration and drainage. The results of Spearman-Rho correlation showed the significant (p < 0.05) correlation with r = -0.873, 0.873, 0.878 and 0.764 between rainfall intensity and drainage coefficient, downstream splash, sediment concentration and soil loss and with r = -0.976, 0.927 and -0.927 between initial soil moisture content and time-to-runoff, runoff coefficient and infiltration coefficient, respectively. © 2014 Leila Gholami et. al.

Kamjoo B.,Sari University of Agriculture and Natural Resources | Baneh H.,Islamic Azad University at Sanandaj Branch | Yousefi V.,Sari University of Agriculture and Natural Resources | Mandal A.,National Dairy Research Institute | Rahimi G.,Sari University of Agriculture and Natural Resources
Journal of Applied Animal Research | Year: 2014

The present study was conducted to estimate variance components and genetic parameters for growth traits of Iran-Black sheep, maintained at the Abbasabad sheep breeding station, located in northeast of Mashhad, (Razavi Khorasan province of Iran) over a period of 24 years (1981 through 2004). Records of 4607 lambs descended from 155 rams, and 1227 ewes were used in the study. Traits included for the present study were birth weight (BW), weaning weight (WW), weight at 6 months (W6), weight at 9 months (W9), and yearling weight (YW). Analyses were carried out by restricted maximum likelihood (REML) fitting an animal model and ignoring or including maternal genetic or permanent environmental effects. Six different animal models were fitted for all traits. The most appropriate model was chosen after testing the improvement of the log-likelihood values. Heritability estimates for weight at birth; weaning; and 6, 9, and 12 months of age were 0.04, 0.14, 0.16, 0.19, and 0.18, respectively. Maternal heritability of body weight declined from 0.33 at birth to 0.04 at six months of age. The maternal permanent environmental component accounted for 6% to 15% to the total variance for all traits under study. The direct-maternal genetic correlation (ram) was positive for all traits and ranged from 0.36±0.27 for BW to 0.99±0.98 for YW, but was never significant. The results showed that modest rates of genetic progress appear possible for all weights. Results also suggest that maternal additive effects were only important in early stages of growth, whereas a permanent environmental maternal effect existed at all ages up to 12 months of age, probably as a carry-over effect of maternal influences present at weaning. Direct genetic correlations (ra1,a2) between traits were positive and ranged from 0.82 (BW-WW) to 0.99 (W6-YW). The estimates of correlation between permanent environmental maternal effect among traits were close to those of ra1,a2. Phenotypic and environmental correlations for all traits were generally lower than direct genetic correlations. © 2013 © 2013 Taylor & Francis.

Rahmanian A.,Sari University of Agriculture and Natural Resources | Hafezian H.,Sari University of Agriculture and Natural Resources | Rahimi G.H.,Sari University of Agriculture and Natural Resources | Farhadi A.,Sari University of Agriculture and Natural Resources | Baneh H.,Islamic Azad University at Karaj
British Poultry Science | Year: 2015

The objective was to investigate inbreeding depression for some economic traits of Mazandaran native fowls using data collected from 1992 to 2012 (21 generations) using a REML animal model of significant fixed and random effects with inbreeding of birds and dams as covariates. The mean inbreeding coefficient (F) for the whole population and dams was 4.67% and 4.12%, respectively, and most of the inbred birds (75.79%) and inbred dams (72.58%) had F < 12.5%. Individual and dam inbreeding trends were 0.55% and 0.53% per year. Inbreeding depression for body weight at hatch, at 8 weeks and 12 weeks of age, age at sexual maturity, weight at sexual maturity, egg weight at 1st d of laying and average egg weight at 28, 30 and 32 weeks of laying due to a 1% increase in individual inbreeding were −0.11 g, −3.1 g, −1.3 g, 0.15 d, 0.59 g, −0.05 g and −0.03 g, respectively. A 1% increase in maternal inbreeding resulted in a reduction of 0.06, 0.6 and 3.6 g in body weight at hatch, 8 weeks and 12 weeks of age. © 2015, British Poultry Science Ltd.

Gholizadeh M.,Sari University of Agriculture and Natural Resources | Gholizadeh M.,Islamic Azad University | Rahimi Mianji G.,Sari University of Agriculture and Natural Resources | Hashemi M.,University of Tehran | Hafezian H.,Sari University of Agriculture and Natural Resources
Czech Journal of Animal Science | Year: 2010

The aim of the present study was to estimate variance components and genetic parameters for birth and weaning weights in Raeini goats. The data were collected from the Breeding Centre of Raeini (BCR) cashmere goats in Kerman province of Iran from 1986 to 2008. Random effects included direct and maternal additive genetic effects, maternal permanent environmental effects with direct-maternal genetic covariance and random residual effects. Variance and covariance components and genetic parameters were estimated using the DFREML program by fitting six single-trait animal models. Depending on the model, h d 2 varied from 0.057 to 0.323 for birth weight and from 0.043 to 0.229 for weaning weight. Estimates of m 2 ranged from 0.016 to 0.289 for birth weight and from 0.01 to 0.184 for weaning weight. The maternal permanent environmental effect was significant for both traits and ignoring maternal effects in the model caused the overestimation of direct heritability.

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