Ghasem Ali Dianati Tilaki; Aliyeh Keshavarz; Bahram Amiri; Ehsan Sadati
Abstract
Effect of salt stress on the stomata variations was studied in Hedysarumcoronarium L. and HedysarumcriniferumBoiss., using optical microscope. The experimental design was a two factorial (species treatments and salt concentrations including 0, 100, 200, 250 mMNaCl) which arranged in a completely randomized ...
Read More
Effect of salt stress on the stomata variations was studied in Hedysarumcoronarium L. and HedysarumcriniferumBoiss., using optical microscope. The experimental design was a two factorial (species treatments and salt concentrations including 0, 100, 200, 250 mMNaCl) which arranged in a completely randomized design with four replicates and 50 seeds per replicate. Seeds were grown in plastic pots with sterile sand. All pots were irrigated by distilled water until germination stage. Then the pots were irrigated uniformly every other day with modified Hoagland’s nutrient solution during 40 days and finally stomata traits were measured. The data was analyzed using SPSS software. The difference between the means was compared using Duncan test (P<0.05). Results showed that the lowest amount of the stomata length, stomata width and area of stomata were observed at 300 Mm salinity stress. Length and width of stomata were reduced by increasing salinity stress. The length stomata decreased 22.33 and 23.76 (μm) for H. coronarium and H. criniferum respectively, while width stomata decreased by 17.13 and 18.62 (μm) respectively. The area of stomata decreased 397.11 and 442.83 (μm²) for H. coronarium and H. criniferum respectively. Salinity stress had positive effect on stomata density (mm²). The highest density of stomata was found in H. criniferumin 250 and 300 mM salinity levels.
Sana Mohebbi; Ghasem Ali Dianati Tilaki; Mehdi Abedi
Abstract
Assessment of rangeland ecological characteristics have been proposed as an important factor inreviewing and monitoring the effects of various management measures and it demands differenttools for quantifying and offering a reasonable criterion for comparison of different managements.For this purpose, ...
Read More
Assessment of rangeland ecological characteristics have been proposed as an important factor inreviewing and monitoring the effects of various management measures and it demands differenttools for quantifying and offering a reasonable criterion for comparison of different managements.For this purpose, the Landscape Function Analysis (LFA) method is capable of displaying thestructural and functional status of pastureland with considering the basic and simple indicators andit can be resorted to as a basis for selecting optimal and sustainable management. In this study, itwas found out that among different types of pasture management in Kojour Noshahr including;exclosure, grazing, plowing and planting management - in almost identical conditions regardingplant types, animal types, soil, geology, and climate the exclosure management was significantly(P<0/05) more favorable than other kinds of managements in terms of structural and functionalfeatures and it was followed by planting and grazing. Meanwhile, the plowed pastures weresignificantly unfavorable (P<0/05) both in terms of structural features and functional characteristics.Therefore; exclosure can be a perfect option to protect rangeland resources in this region.
Ghasem Ali Dianati Tilaki; Ali Mohammadsharifi; Seyed Jalil Alavi
Abstract
The present study was conducted in the rangeland of Glandrood watershed in the province of Mazandaran. The objective of this study was to compare between the ecological amplitude of Festuca ovina L., and Poa bulbosa L., using the function HOF along the gradient of the environmental variables. For this ...
Read More
The present study was conducted in the rangeland of Glandrood watershed in the province of Mazandaran. The objective of this study was to compare between the ecological amplitude of Festuca ovina L., and Poa bulbosa L., using the function HOF along the gradient of the environmental variables. For this purpose 150 plots of 1m2 were established along the altitude gradient. The sampling method was randomized-systematic. In the area sampled, frequency of Festuca ovina and Poa bulbosa, altitude and slope were recorded. Soil samples were taken from 0-20 cm in each plot. In each sample, bulk density, pH, N, EC, organic matter, organic carbon, the percentage of sand, silt and clay were measured. In order to study the shape of response curve and the ecological optimum in relation to the mentioned variables, HOF function was used with binomial distribution function. The data were analyzed by R ver.3.0.2 software. The two species Festuca ovina and Poa bulbosa, mainly showed different ecological amplitude along the gradient environmental variables. The results showed that the ecological amplitude and optimum alonge altitude gradient for Festuca ovina has been recorded 2244-3037m and 3037m respectively for Poa bulbosa 2335-3037m and 2636 m respectively. Also the response curve of Poa bulbosato the altitude has unimodal and symmetric but for Festuca ovina was monotonically increasing trend. The response curve ofPoa bulbosato pH is monotonically decreasing but for Festuca ovina was unimodals symmetric.
