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Investigation of salinity impacts on germination and growth of two forest tree species at seedling stage

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Journal of Forestry Research 2013年第4期24卷 703-708页

作者： seyed Mohammad hosseini Nasr Sekineh Kiani Savadkoohi Elahe Ahmadi Department of Forestry Sari Agricultural Sciences and Natural Resources University

Soil salinity is becoming an increasingly serious constraint to plant growth in many parts of the world; this is particularly common in semi-arid and arid zones. This study was conducted to evaluate the effect of different concentrations of salt on seed germination and seedling growth of Acacia albida and A. salicina. Collected seeds were treated with H2SO4 98% for 35 min then left to germinate in a controlled growth chamber. Seeds were grown at salinity levels of 0.1, 0.2 and 0.3 mol.L1 of NaH2PO4.H20. Germination parameters and seedling growth indices were measured after 35 days. The mean of total length ofA. salicina in all salinity concentrations was more than that of ：4. albida. The fresh weight of stem and root of ：4, albida was more than that of ：4. salicina. Growth of control seedlings was higher than for other treatments and the fresh weight of stems of two species at salt concentrations of 0.2 and 0,3 *** decreased with increasing concentration of salt. Most Control seeds germinated at salinity of 0.1 *** and germination index, final germination and seeds stamina was greater at low levels of salinity.

关键词： soil salinity germination salt concentration Acacia albida,Acacia salicina.

Biodegradable starch/poly(vinyl alcohol) film reinforced with titanium dioxide nanoparticles

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International Journal of Minerals,Metallurgy and Materials 2013年第10期20卷 1001-1011页

作者： Zahra Hejri Ali Akbar Seifkordi Ali Ahmadpour seyed mojtaba Zebarjad Abdolmajid Maskooki Department of Chemical Engineering Science and Research BranchIslamic Azad University Department of Chemical Engineering Ferdowsi University of Mashhad Department of Materials Science and Engineering Engineering FacultyShiraz University Research Institute of Food Science and Technology

Biodegradable starch/poly （vinyl alcohol）/nano-titanium dioxide （ST/PVA/nano-Ti02） nanocomposite films were prepared via a solution casting method. Their biodegradability, mechanical properties, and thermal properties were also studied in this paper. A general full factorial experimental approach was used to determine effective parameters on the mechanical properties of the prepared films. ST/PVA/TiO2 nanocomposites were characterized by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results of mechanical analysis show that ST/PVA films with higher contents of PVA have much better mechanical properties. In thermal analysis, it is found that the addition of Ti02 nanoparticles improves the thermal stability of the films. SEM micrographs, taken from the fracture surface of samples, illustrate that the addition of PVA makes the film softer and more flexible. The results of soil burial biodegradation indicate that the biodegradability of ST/PVA/TiO2 films strongly depends on the starch proportion in the film matrix. The degradation rate is increased by the addition of starch in the films.

关键词： nanocomposite films titanium dioxide nanopaxticles biodegradability mechanical properties thermogravi-metric analysis

Kernel Search-Framework for Dynamic Controller Placement in Software-Defined Network

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Computers, Materials & Continua 2021年第9期68卷 3391-3410页

作者： Ali Abdi seyedkolaei seyed Amin hosseini Seno Rahmat Budiarto Faculty of Engineering Ferdowsi University of MashhadMashhadIran Department of Informatics Faculty of Science and TechnologyUniversitas Alazhar IndonesiaJakartaIndonesia

In software-defined networking(SDN)networks,unlike traditional networks,the control plane is located separately in a device or *** of the most critical problems in these networks is a controller placement problem,which has a significant impact on the network’s overall *** paper attempts to provide a solution to this problem aiming to reduce the operational cost of the network and improve their survivability and load *** researchers have proposed a suitable framework called kernel search introducing integer programming formulations to address the controller placement *** demonstrates through careful computational studies that the formulations can design networks with much less installation cost while accepting a general connected topology among controllers and user-defined survivability *** researchers used the proposed framework on six different topologies then analyzed and compared with Iterated Local Search(ILS)and Expansion model for the controller placement problem(EMCPP)along with considering several evaluation *** results show that the proposed framework outperforms the ILS and ***,the proposed framework has a 38.53%and 38.02%improvement in reducing network implementation costs than EMCPP and ILS,respectively.

关键词： Software-defined network controller placement kernel search integer programming survivability cost

Efficacy of premedication with activated Dimethicone or N-acetylcysteine in improving visibility during upper endoscopy

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World Journal of Gastroenterology 2011年第37期17卷 4213-4217页

作者： seyed Mohammad Kazem hosseini Asl Gholam Reza Sivandzadeh Department of Internal Medicine Nemazee HospitalShiraz University of Medical Sciences

AIM:To assess the efficacy of N-acetylcysteine(NAC) and activated Dimethicone in improving endoscopic mucosal ***:A total of 148 patients were randomly allocated into four groups to receive one of the following premedications:group A:100 mL water alone;group B:activated Dimethicone plus water(up to 100 mL);group C:NAC plus water(up to 100 mL);and group D:activated Dimethicone and NAC plus water(up to 100 mL).A single endoscopist blinded to the patients group assessed the gastric mucosal visibility scores(range 1-4) at four *** sum of the scores from the four sites was considered as the total mucosal visibility score(TMVS).RESULTS:The patients in group B showed a significantly lower TMVS than those of groups A and C(P 0.05).The difference between TMVS of groups C and A was not significant(P > 0.05).CONCLUSION:Premedication with activated Dimethicone 20 min prior to the upper endoscopy leads to the best *** does not improve visualization by itself.

关键词：二甲基硅油高能见度半胱氨酸疗效观察内窥镜术激活乙酰用药

Desertification hazard zoning in Sistan Region, Iran

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Journal of Geographical Sciences 2012年第5期22卷 885-894页

作者： seyed Mahmood hosseini Sahar SADRAFSHARI Mehdi FAYZOL.AHPOUR Member of Young Researchers Club Arsanjan Branch Islamic Azad University Arsanjan Irar M.A. student and Member of Young Researchers Club Tabriz Branch Islamic Azad University Tabriz Iran Ph.D student and Member of Young Researchers Club Tabriz Branch Islamic Azad University Tabriz Iran

Desertification process as a great problem affects most of the countries in the world. This process has a high rate in arid and semiarid areas. Today, human societies are en- countering the desertification phenomenon as a serious problem which causes various ir- reparable damages to economic and social sectors. In order to assess desertification results in production of different regional models for their application in another region the indices should be re-investigated and adjusted to local conditions. Several models have been de- veloped for desertification evaluation. The present study, attempts to assess quantitatively the desertification process has in an area located at Sistan plain of Iran （Niatak region as a case study） by using Modified MEDALUS method. The obtained results indicated that of the whole studied region （comprising 4819.6 acres）, 2651.56 acres （55%） are located in medium de- sertification intensity class, 1269.48 acres （26.34%） are positioned in severe desertification intensity class, and 898.54 acres （18.64%） are placed in vary severe desertification intensity class.

关键词： desertification modified MEDALUS model desertification process Niatak region

Prediction of the soil erosion in a forest and sediment yield from road network through GIS and SEDMODL

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International Journal of Sediment Research 2014年第1期29卷 118-125页

作者： Aidin PARSAKHOO Majid LOTFALIAN Ataollah KAVIAN seyed Ataollah hosseini Department of Forestry Gorgan Agricultural Sciences and Natural Resources University Department of Watershed Management Sari Agricultural Sciences and Natural Resources University Department Forestry Sari Agricultural Sciences and Natural Resources University University of Tehran

This study was conducted to classify water erosion risk for a deciduous forest and to predict the amount of sediment yield from forest road *** in combination with AHP was used for determining the soil erosion risk degrees of ***,sediment yield from forest roads with gravel and asphalted surfacing was estimated using *** simulator was used in calibration and validation process of *** showed that47.9%of forest soil is classified from moderate to very high vulnerability.32.3%of roads were located in soil erosion risk class of very *** class is generally found in the eastern region of forest,while areas with very low risk are found in the south western part.14.6%of the forest roads were ranked as having very low sediment *** 61 segments out of 339 segments of forest road network delivered sediment to the ravine *** estimated annual sediment yield for all of road sections by SEDMODL and rainfall simulator were 10,935.45 and10,509.29 g m,*** of the calibration and validation process showed that the variation accounted for in the predicted values by SEDMODL with the observed values under rainfall simulation was 3.90%.Best management practices(BMP) must be considered for the areas with high degrees of erosion risk.

关键词： Soil erosion Forest road GIS SEDMODL

Assessment of soil erodibility and aggregate stability for different parts of a forest road

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Journal of Forestry Research 2014年第1期25卷 193-200页

作者： Aidin Parsakhoo Majid Lotfalian Ataollah Kavian seyed Ataollah hosseini Department of Forestry Faculty of Forest SciencesGorgan Agricultural Sciences and Natural Resources University Associate Professors Department of ForestryFaculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University Assistant Professor Department of Watershed ManagementFaculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University

We measured erodibility and mean weight diameter （MWD） of soil aggregates in different parts of a forest road. Samples of topsoil were collected from cutslope, fillslope, road surface and forest ground to assess the texture, bulk density, moisture, CaCO3 and organic matter. Soil aggregate stability was determined by wet sieving. Soil erodibility on the road surface was 2.3 and 1.3 times higher than on the fillslope and cutslope, respectively. The forest soil had the lowest erodibility. Aggregate stability of cutslope and road surface were low and very low, respectively. There was a significant negative relationship between cutslope erodibility with CaCO3 and sand content. Cutslope erodibility increased with increasing silt, clay and moisture content. On fillslopes, MWD increased with in-creasing rock fragment cover, plant cover, litter cover, organic matter and sand. There was a strong negative correlation between fillslope erodibility and organic matter, sand and MWD. There was no significant difference between erodibility of bare soil and soils beneathRubus hyrcanusL. and Philonotis marchica （Hedw.） Brid.

关键词： road prism soil erodibility aggregate stability wet sieving Lat Talar forest

Herbaceous species diversity in relation to fire severity in Zagros oak forests,Iran

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Journal of Forestry Research 2014年第1期25卷 113-120页

作者： Morteza Pourreza seyed Mohsen hosseini Ali Akbar Safari Sinegani Mohammad Matinizadeh seyed Jalil Alavai Department of forestry Tarbiat Modares University Soil department Bu-Ali Sina University Research Institute of forest and range lands

Zagros forests are mainly covered byQuercus brantii L. coppices and oak sprout clumps occupy the forest area like patches. We investigated post-fire herbaceous diversity in the first growing season after fire. For this purpose neighboring burned and unburned areas were selected with the same plant species and ecological conditions. The data were collected from areas subjected to different fire severities. Overall 6 treatments were considered with respect to fire severity and the mi-crosites of inside and outside of oak sprout clumps including： unburned inside and outside of sprout clumps （Ni and No）, inside of sprout clumps that burned with high fire severity （H）, inside of sprout clumps that burned with moderate fire severity （M）, outside of sprout clumps that burned with low fire severity （OH and OM）. Different herbaceous com-position was observed in the unburned inside and outside of oak sprout clumps. The species diversity and richness were increased in treatments burned with low and moderate fire severity. However, in treatment burned with high fire severity （H）, herbaceous cover was reduced, even-ness was increased, and richness and diversity were not significantly changed. We concluded that besides the microsites conditions in forest, fire severity is an inseparable part of the ecological effect of fire on her-baceous composition.

关键词： biodiversity fire severity Oak sprout clump Zagros forests,microsite

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