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Effects of geometric design of forest road and roadside vegetation on traffic noise reduction

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Journal of Forestry Research 2016年第2期27卷 463-468页

作者： Seyed Ata Ollah Hosseini Seyran Zandi asghar fallah Mehran Nasiri Department of Forestry and Forest Economics Faculty of Natural Resources University of Tehran Department of Forestry Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources Alborz Road Development and Construction Corporation Civil Engineers office

Geometric design of forest roads and design of their landscapes can reduce noise pollution and its harmful effects on human health. We investigated the effects of technical and biological parameters such as geometric road design and various roadside tree stands on reducing noise pollution according to the tree density and distance from roadway in Darabkola Forests, Sari, Iran. We recorded the noise generated by a car （Land Rover） relative to changes in longitudinal slope, horizontal curve radius and type of road pavement. We also measured noise levels according to roadside tree density and stand type （coniferous and hardwood） in 40 rectangular plots of three widths （25, 100 and 300 m） and 50 m length that were randomly demar- cated along forest roads. The changes in noise level were recorded using a decibel meter with an accuracy of q-1.5 dB and resolution of 0.1 dB. Noise levels were higher alongside unpaved roads than alongside paved roads. There was an inverse relationship between the measured noise level and horizontal curve radius. The rate of noise level on horizontal curve with a radius less than 30, 30-45 m and more than 45 m were 64.8, 70.8 and 75.9 dB, respectively. The noise level increased with the increasing longitudinal slope of the road. There was a significant difference between the noise level on slopes less than 3 % （67 dB） and 3-8 % （71.2 dB） in comparison with slopes greater than 8 % （77.8 dB）, （p 〈 0.05）. Pinus brutia L. reduced the noise level more （about 6 dB） in stands of 1/3 density of mixed hardwoods within 25 m from middle of the road. Careful design of geometric properties of forest roads as well as planting coniferous trees with hardwoods is a suitable solution for reducing noise pollution.

关键词： Forest road Noise pollution Noise level Vegetation Distribution

Mixed-effects modeling for tree height prediction models of Oriental beech in the Hyrcanian forests

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Journal of Forestry Research 2018年第5期29卷 1195-1204页

作者： Siavash Kalbi asghar fallah Pete Bettinger Shaban Shataee Rassoul Yousefpour Sari Agriculture and Natural Resource University SariMazandaran Iran Warnell School of Forestry and Natural Resources University of Georgia Athens GA USA Gorgan Agriculture and Natural Resource University Gorgan Golestan Iran Faculty of Environment and Natural Resources University of Freiburg Freiburg Germany

Height–diameter relationships are essential elements of forest assessment and modeling *** this work,two linear and eighteen nonlinear height–diameter equations were evaluated to find a local model for Oriental beech（Fagus orientalis Lipsky） in the Hyrcanian Forest in *** predictive performance of these models was first assessed by different evaluation criteria： adjusted R^2（R^2_（adj））,root mean square error（RMSE）,relative RMSE（%RMSE）,bias,and relative bias（%bias） *** best model was selected for use as the base mixed-effects *** parameters for test plots were estimated with different tree selection *** show that the Chapman–Richards model had better predictive ability in terms of adj R^2（0.81）,RMSE（3.7 m）,%RMSE（12.9）,bias（0.8）,%Bias（2.79） than the other ***,the calibration response,based on a selection of four trees from the sample plots,resulted in a reduction percentage for bias and RMSE of about 1.6–2.7%.Our results indicate that the calibrated model produced the most accurate results.

关键词： Random effects Tree height Calibration Sangdeh forest Chapman–Richards model Oriental beech

Impact of land-use management on nitrogen transformation in a mountain forest ecosystem in the north of Iran

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Journal of Forestry Research 2013年第1期24卷 115-119页

作者： Maryam Asadiyan Seyed Mohammad Hojjati Mohammad reza Pourmajidian asghar fallah Sari Agricultural Sciences and Natural Resources University Sari-Iran.

Soil inorganic N is one of the most important soil quality indexes, which may be influenced by land-use change. The historical conversion of land-use from native vegetation to agriculture resulted in sharp declines in soil N dynamics. This study was conducted to determine the soil inorganic N concentrations and net N mineralization rate in four common types of land-uses in the mountain forest area in the north of Iran, namely arable land, pine plantation, ash plantation, and beech stand. The soil samples were taken from top mineral soil layer （5 cm） in each site randomly （n=6） during August- September 2010. Beech stand and ash plantation showed significantly higher total nitrogen compared with arable land and pine plantation, while extractable NH4 ＋-N concentration was significantly greater in Beech stand compare to arable soils （p〈0.05）. No significantly difference was found in Net N mineralization, net nitrification and net ammonification rates among different land-uses. Results showed that net N mineralization and ammonification were occurred just in the soil of Ash plantation during the incubation time. Our findings suggested that conversion of Hyrcanian forests areas to pine plantation and agricultural land can disrupt soil natural activities and affect extremely soil quality.

关键词： soil quality net N mineralization nitrogen dynamic land use Hyrcanian forest Alandan.

Estimation of conservation value of myrtle(Myrtus communis)using a contingent valuation method:a case study in a Dooreh forest area,Lorestan Province,Iran

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Forest Ecosystems 2016年第1期3卷 26-36页

作者： Neda Amiri Seyed F.Emadian asghar fallah Kamran Adeli Hamid Amirnejad department of forestry sari agricultural and natural resource universitySariIran department of forest sciences gorgan agricultural and natural resource universityGorganlran department of forestry college of natural resourcessari agricultural sciences and natural resources universitySariIran department of forestry faculty of agriculturaluniversity of lorestanlorestanIran department of agricultural economics sari agricultural and natural resource universitySariIran

Background： Around 2000 plant species occur naturally in Lorestan Province of which 250 species are medicinal and myrtle is one of them. Myrtle is a shrub whose leaves and fruits have medicinal value and thus, if managed and harvested properly, could produce sustained economic benefits. In recent years, however, over half of the myrtle site areas was destroyed, due to inappropriate management and excessive harvesting practices. Thus, coming up with a practical harvesting approach along with identifying those factors damaging the sites, seems to be very crucial. Methods： In our investigation, we calculated the conservation value per hectare of myrtle in the Dooreh forest area in Lorestan Province. Using the Contingent Valuation （CV） and Double Bounded Dichotomous Choice （DBDC） methods, we determined the willingness to pay （VVTP） for myrtle conservation. The VVTP was estimated with a Iogit model for which indices were obtained based on a maximum precision criterion. Results： The results showed that 86.67 per cent of people were willing to pay for the conservation of these myrtle sites. Average monthly WTP per family was calculated as $0.79. The annual conservation value in terms of WTP for the preservation of the myrtle sites in Dooreh was estimated as $102,525. Among the variables of the model presented, education had a positive impact, while the amount proposed for payment and family size had a negative impact on the WTP. Conclusions： Our estimate of the value of myrtle conservation should provide justification for policy makers and decision making bodies of natural resources to implement policies in order to conserve the natural sites of this species more effectively.

关键词： Conservation value Myrtle Contingent valuation method Double Bounded Dichotomous method Logit model

Effect of shelterwood cutting method on forest regeneration and stand structure in a Hyrcanian forest ecosystem

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Journal of Forestry Research 2010年第3期21卷 265-272,395页

作者： Mohammad Reza Pourmajidian Hamid Jalilvand asghar fallah Seyed Ataollah Hosseini Aidin Parsakhoo Amin Vosoughian Ali Rahmani Department of Forestry Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University Department of Forestry Faculty of Natural ResourcesMazandaran University

A study was carried out to evaluate the effect of shelterwood cutting methods on stand structure and regeneration density. Data were collected from a northern hardwood forest stands in Iran with Fagus orientalis Lipsky as dominant species, with/without shelterwood cutting operation. Results clearly demonstrate that the management of Fagus orientalis Lipsky with shelterwood cutting system affected the frequency and diversity of the understory herbaceous species. The frequency of Viola silvestris Lam., Asperula odorata L., Carex spp. and Rubus hyr-canus Juz increased significantly after shelterwood cutting. The DBH （diameter at breast height） of commercial species in control stands （57.50±2.15 cm） was greater than that in treated stands （50.67±1.88 cm）, whereas the total height of trees was similar between treated and control plots （21±0.5 m）. The number of Parrotia persica seedlings increased by 13.2% from 1995 to 2005 whereas the number of Fagus orientalis and Carpinus betulus seedlings significantly decreased from 1995 to 2005. In conclusion, it confirms that instead of shelterwood cutting method other silvicultural practices such as selection cutting method should be applied for the mountainous beech stands of Hyrcanian forests.

关键词： Shelterwood cutting stand structure regeneration Fagus orientalis Lipsky

Treatment of cows with clinical endometritis Ⅲ as cows affected by pyometra-Non antibiotic treatment of severe clinical endometritis

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Asian pacific Journal of Reproduction 2018年第4期7卷 185-190页

作者： Mohammad Rahim Ahmadi asghar Mogheiseh Abdolah Mirzaei Saeed Nazifi Eisa fallah Department of Clinical Sciences School of Veterinary MedicineShiraz UniversityShirazIran

Objective: To confirm the efficacy of non-antibiotic treatment with prostaglandin F2α(PGF2α) in dairy cows affected by severe clinical endometritis in (30±3) days in milk. Methods: Cows with clinical endometritis Ⅲ (n=399) were aligned into three groups randomly. The first group (n=115) received PGF2α, the second group (n=84) received intrauterine infusion (IUI) of oxytetracycline 10% + PGF2α, and the third group (n=200) received IUI. Cows were inseminated following estrus. The pregnancy status, parity, calving and artificial insemination season, ovaries with corpus luteum at the time of treatment, dystocia, body condition score and treatment groups were included in data analysis. Results: Total pregnancy rate was 40.1% after the first insemination and 94.2% after the third insemination. Overall pregnancy rate of treated cows with IUI+PGF2α(84.5%) was significantly lower than the treated cows with PGF2α(98.3%) or IUI (96%) (P<0.05). The first service pregnancy rate of inseminated cows in summer (14.3%) was lower in comparison with cows inseminated in spring (40.4%), fall (41.4%) and winter (51.7%) (P<0.05). Conclusions: PGF2α could treat severe clinical endometritis in dairy cows with corpus luteum in comparison with other treatments.

关键词： Cow Endometritis Reproductive performance Prostaglandin F2α