moslem yazdani; reza erfanzadeh; Asghar Mosleh Arani
Abstract
Study of the effect of woody plant species on the production, diversity and richness of substratum herbaceous species, especially in the arid and semiarid regions, is essential for the proper management of these ecosystems. Therefore, the rangelands of Chenarnaz region in Khatam city in Yazd province ...
Read More
Study of the effect of woody plant species on the production, diversity and richness of substratum herbaceous species, especially in the arid and semiarid regions, is essential for the proper management of these ecosystems. Therefore, the rangelands of Chenarnaz region in Khatam city in Yazd province were selected and then, using 0.5m×0.5m quadrats, vegetation sampling was performed under the selected 15 sites from Daphne mezerum, Amygdalus scoparia and Ebenus stellate (growing in equal topographical conditions) canopies, and outside of the canopies (as control). In each quadrat, the cover percentage of each plant species was visually estimated and the productions were measured by clipping and weighing method. The species diversity and richness indices were calculated using Past software through introducing the plant covers into the software. The results showed that the most values of Shannon-Weaner and Simpson diversity indices were found under A. scoparia (2.07 and 0.80, respectively) and the lowest values were found under E. stellata (1.010 and 055, respectively). In addition, the highest values of Menhinik and Margalef richness indices were found under A. scoparia (4.90 and 3.43, respectively) and D. mezerum (4.25 and 3.12, respectively), while the highest production was found under E. stellata (64.76 g/m2). The results of this study showed that different woody species had the desired but different effects on the herbaceous species, in such, A. scoparia and D. mezerum had significant positive effects on species diversity and E. stellata increased significantly species production; therefore, conservation of all woody species is emphasized in the region.
mahshid souri; mina bayat; Hossein Arzani; Morteza khodagholi
Abstract
Climatic factors are the most important factors affecting vegetation growth and production. The impact of each of these factors in each region varies depending on the vegetation type. The effect of climatic factors (rainfall and temperature) on the production of grazed plant species at 6 steppe sites ...
Read More
Climatic factors are the most important factors affecting vegetation growth and production. The impact of each of these factors in each region varies depending on the vegetation type. The effect of climatic factors (rainfall and temperature) on the production of grazed plant species at 6 steppe sites in Fars province over a ten year period (1998 to 2007) was investigated. 60 plots of 2 square meters along 4 transects of four hundred meters were used to measure cover and production was measured by cutting and weighing method in 15 plots along transects. Then, using regression relationship between canopy cover (percent) and production (kg ha-1), the residual plot yield was calculated for that year. Important climatic indices analyzed in this study are: annual rainfall, growing season rainfall (March to June), plus and earlier rainfall, annual temperature, July temperature, August, maximum and minimum temperatures. The results showed that the average canopy cover was 6.3% and the average yield was 128.5 kg / ha and among the different vegetative forms of shrubs had the highest percentage of cover and production and wheat had the lowest cover and production percentage. Among the important climatic indices, annual rainfall and August temperature at all sites and the growing season rainfall at all sites except for the desired site were the most effective indicators on forage production and showed a positive and significant correlation with forage production.
majid mohammad esmaeili; mohammadreza Mojtahedi; Khironesa Mirnia
Abstract
Flooding is one of the most important environmental stresses that affect the performance of plants. The effects of flooding height on the performance of the two species A.littoralis, J.maritimus were studied. This experiment was carried out the factorial experiment in a completely randomized design with ...
Read More
Flooding is one of the most important environmental stresses that affect the performance of plants. The effects of flooding height on the performance of the two species A.littoralis, J.maritimus were studied. This experiment was carried out the factorial experiment in a completely randomized design with 4 treatments and 8 replications. After 2.5 months of ultimate recovery tests were performed. The number and length of stolons of A. littoralis were counted separately in each treatment. The number and length of rhizome J. maritimus species in each plot (pot) were counted. The total weights of dry matter, shoot dry weight, dry weight of underground organs were measured in each experimental unit. Analysis of variance showed that the effects in controlling the height of flooding on all performance indicators studied (excluding the effects of flooding on root dry weight) of two species A. littoralis and J. maritimus is significant. Comparison of performance indicators A. littoralis species show between the two treatment groups (7 cm below the water level and water treatment) and treatment (treatment without irrigation and 15 cm below the water level) there is a significant difference. Comparison of performance indicators J. maritimus species show a significant difference in the number of rhizome, total length of underground rhizome and dry weight were observed. Comparison of dry pasture species show the highest production of the two types of treatment 7 cm below the water level.
mina bayat; Hossein Arzani; adel jalili; hassan ghalij nia
Abstract
In this study the effects of three important factors: the climatic precipitation, temperature and relative humidity on the amount of canopy cover and forage production in a period of five years (1381-1385) and 1392 in semi-steppe rangelands Reineh and Polur in the Mazandaran province studied. The statistical ...
Read More
In this study the effects of three important factors: the climatic precipitation, temperature and relative humidity on the amount of canopy cover and forage production in a period of five years (1381-1385) and 1392 in semi-steppe rangelands Reineh and Polur in the Mazandaran province studied. The statistical models (simple and multiple regression) to find the relationship between various forms of vegetative cover and annual forage plants using climate variables in different periods of time with Minitab.14 and Excel software was used for data analysis. The results of six years of study in a semi-steppe rangelands Polur and Reineh showed an average canopy cover of 51 percent and the average yield was 372 kg per hectare. The total vegetation cover of Rineh pastures had the most relation with a total rainfall of the growth season and the March and the average temperature. The temperature was more effectively than rainfall in annual yield. And The yield affected by July temperature. The total vegetation cover of polur had not significant relation with climate factors but each of the vegetation form in Different time base had significant relation. The total grazing species yield of plour affected by growth season rainfall. So instead of one year measurement of vegetation cover and production can be estimated the production and vegetation cover fluctuation according to climate parameters. With long-term vegetation cover and production data, can be determined the available forage and pasture capacity to prevent the range degradation.
