جستجوی مقالات مرتبط با کلیدواژه "گرمسار" در نشریات گروه "آبخیزداری، بیابان، محیط زیست، مرتع"

Due to the adaptability to arid and desert conditions, halophytes could supply a part of livestock forage requirement in early spring, summer, and especially autumn. However, there is little information on the forage quality of these plants. On the other hands, halophytes vary considerably in their nutritive value not only among species but also among phenological stages. Therefore, knowledge on forage quality of halophytes at each phenological stage could help the beneficiaries in arid regions to opt proper species for cultivation in haloculture programs as well as determining the suitable time for livestock grazing. In the present study, the effects of phenological stages on six forage quality traits were investigated for two halophytes ie., Atriplex leucoclada and Suaeda fruticosa. Plant samples were collected from saline lands in Garmsar, Semnan Province. The study was conducted in a completely randomized design with three replications. The results showed that the effects of phenological stages and species on forage quality were significant (P

Carbon absorption by plant tissues and sequestration in soil is one of the ways to reduce greenhouse gases in the atmosphere. The cultivation of plants and proper management lead to increased biomass of native plants, increased photosynthesis level and carbon adsorption as well as increasing the amount of carbon input to soil.Roadside is among the areas having the ability to absorb carbon with a high ecological potential. The aim of this research was to measure the carbon storage in the sagebrush stands of the Eyvanakey-Garmsar roadside. For this purpose, 10 plots of 120 square meters were randomly established along three transects of 1,000 meters. In each plot, soil profiles were dug at the foot of the plants and the space between them, and soil samples were taken at three depths of 0-10 cm, 10-30 cm, and 30-50 cm in five replications. According to the obtained results, the total carbon sequestration in the soil profile was calculated to be 59.518 tons per hectare, and the total organic carbon stored in the aboveground and underground biomass of sagebrush was equal to 340.8 kg per hectare. To increase carbon sequestration in rangelands, the applied ecosystem management options must be based on three criteria including soil, biomass, and litter. Overall, plant cultivation in the roadside will result in reduced erosion and noise pollution as well as creating ecological corridor, landscape, and microclimate.

In this study, the amount of carbon storage in a Haloxylon aphyllum stands in road edge were measured Garmsar - Eyvanakey highway is a one of the most important and high traffic roads in Iran that adjacent to the Capital, and it's caused air pollutions. We collected 11 plots 500 m2 from the road edges (60 meters on each side from axe) for measurements of vegetation and soil parameters. The results showed that the cumulative carbon sequestration in forest soil profiles in H.aphyllum afforested is equal to 47.72 tons per hectare. The Duncan test results showed no significant difference between the mean layer of 10 to 30 and 30 to 90 cm However, between the two mentioned layers with surface soil (0 -10 cm) have a significant differences (p<0.05). The carbon percentage in the aerial organs included leaves, and steam in compare with below ground biomass have been significant differences. The total amounts of carbon storage in the both of aerial and below ground organs are equal 582.2 Kg per hectare, and also the cumulative carbon sequestrations in soil and plant parts of this afforestations are equals 53.54 tons per hectare. We should consider the potentials of the width of highways, and network roads for carbon sequestrations. The advantages of the establishments of vegetation cover are: decrease and controlled the erosion, make up the ecologically corridors, general landscape, decrease of noise pollution, as well as make up the new microclimate.

Desertification consists of land degradation in arid, semi-arid and dry sub-humid areas induced by climate change and human activities. For evaluation and mapping of desertification many research have been conducted leading to regional and local models. In this research, among different existing methods, IMDPA‌ model was selected and desertification intensity of Garmsar plain was evaluated based on 2 criteria and 6 indices including: climate (precipitation, drought and aridity index) and water (groundwater table depletion, electrical conductivity, sodium absorption ratio) over four periods; 1995-1997, 1997-2003, 2003-2009 and 2010-2012. Each criterion was assessed based on the selected indices resulted in qualitative mapping of each criterion based on geometric average of the indices. Finally, desertification map of the region was extracted using geometric average of criteria for each period. Thematic databases, with a 1:50000 scale resolutions were integrated and elaborated in ArcGIS9.3. The results showed that during the periods, four indices including groundwater table depletion, electrical conductivity, aridity index and precipitation index have the most significant effects on desertification with the values of 3.81, 3.17, 3.11 and 3.09, respectively. Also two indices including Sodium absorption ratio and drought have the least effect on desertification with the values of 1.17, 1.63 of the Plain, respectively. Also, analysis of desertification criteria in Garmsar region showed that among studied criteria, water criteria have had the most effect on land degradation and desertification since 1994.

This study is about the relation between erodibility rate and plasticity features of Neogene Marl deposits of Gatchab and Gitcha in southeast of Garmsar. The erosions al feature of Neogene sediments are rill، gully and waterway shapes. The depth of soil sampling for rill and waterway types is from surface to 30-centimeter thickness and for gully one is from head cut and all outcrop of gully bank. The engineering analyses for sediments include liquid limit، plastic limit and plastic index and engineering granulometry. On the basis of engineering classification of soil، the sediment of Gatchab and Siahkoh mountains are fine grained soils with low to very low degree cohesive، consequently low plastic limit and low internal consistency. The comparison of the results between marl units of Gatchab and Gitcha area have shown the M2 unit has low plasticity and high sensitive to erosion to other units M1 and M2. By the way، the M1 unit is high resistance to water erosion in comparison to M3 unit. From all aspect، Abundance of the lime and clay particle amounts is positive effects on decreasing of sensitivity rate to erosion of Neogene deposits. The above mentioned results base on plasticity features of Neogene deposits confirmed by field witness.