IRANIAN JOURNAL OF RANGE AND DESERT RESEARCH
Year:2016 | Volume:23 | Issue:3 |Papers Count:21

This research was aimed to evaluate the agronomic and quality traits of sainfoin (Onobrychis sativa L. ) available in the Natural Resources Gene Bank of Iran. The study was conducted in a complete randomized block design with two replications in Karaj (Alborz Iran) for two years. Forage dry matter and seed yield, plant height, number of primary and secondary branches, number of seeds per plant, 1000-seed weight, powdery mildew disease infection, and the quality traits including dry matter digestibility (DMD), crude protein (CP), water soluble carbohydrates (WSC), crude fiber (CF), Acid detergent fibre (ADF) and total ash, were measured. The results showed that the populations of 3001 (Karaj) and 8206 (Tehran) had the higher mean values for agronomic traits. Populations 3001 (Karaj), and 11815 (Khalkhal) had priority for both dry matter yield and forage quality than other populations. The result of correlation analysis showed that both dry matter yield and seed yield were positively correlated with plant height and number of primary and secondary branch. Crude protein was positively correlated with seed yield, number of seed per plant, DMD and total ash and negatively correlated with ADF and CF. In principal component analysis, the first three components accounted for 50% of total variation among the populations. The contributions of the first to the third components were 23%, 17%, and 11%, respectively. This classification was in agreement with the classification of populations based on first two components. In cluster analysis, the populations were classified into four groups in a Euclidean distance of 18. 5. The members of each group had the same traits.

This study aims to determine the priority of disposed zones of desert tourism in Isfahan province. With respect to the components, the research type is applied and developmental and the research method is descriptive and survey. In this study Rating are given to the attractions of the desert and sand dunes based on performance levels (national, regional, international), privileges (infantry, cavalry), hotels and climate, . Maranjab desert in Natanz and Aran, Mesr desert in Khoor, Siahkooh, Rigjen and a part of Kavir plain in naein, Daghsorkh in Ardestan, and Varzaneh sand dunes in Isfahan, have desert tourism potential in Isfahan province. The results show that the best areas for desert tourism development based on performance levels, privileges, hotels and climate are Abbas Abad and Matin Abad villages and the cities of Islamabad, Khalidabad and Badrod in Natanz, Mesr and Farahzad vilages in Khor And Hossein Abad and Abuzeydabad villages in Aran Bidgol. After that, Respectively, Choupanan village in the Nain, Amir Abad and Hossein Abad villages in Ardestan and Varzaneh in Isfahan have the most score for desert tourism development.

The structure and composition of plant communities are mainly affected by fire and grazing, especially in arid and semiarid rangelands. This study aimed to investigate the role of fire and grazing on soil seed bank characteristics (density, diversity and species richness) in semi-steppe rangelands of Central Zagros. A stratified random sampling was used to collect the data from 12 sites with one and five years after the last fire, and with long term light and heavy grazing history. Soil samples were collected in the autumn by auger from 0-5 and 5-10 cm from the soil surface, and the samples were cultivated in the greenhouse. All the germinated seeds were identified and counted for a 6-month period. The results showed that the one year after fire treatment under both light and heavy grazing resulted to a significant decrease in density, richness, and diversity of the soil seed bank. The richness and diversity of soil seed bank in the fiveyear after fire treatment and under light grazing pressure increased significantly compared to its control site. According to the results, the soil seed bank in 5 to 10 cm from the soil surface did not vary statistically under fire and grazing pressure, indicating the role of soil depth in reducing the impact of fire and grazing. Overall, it can be concluded that the grazing management after a fire event has a key role in vegetation restoration through its effects on the soil seed bank.

This study was aimed to determine the feasibility of spatial statistics in studying the spatial variations of density, canopy cover, and production for Artemisia fragrans in the southeast slopes of Sabalan. Initially, the normality test was conducted using SPSS16 software. Then, spatial statistical analysis including studying the spatial variability of density, canopy cover, and production of the studied species were conducted through the variograms of data and mapping the parameters using different interpolation and spatial statistical methods in the GS+5 and ArcGIS10 software. The accuracy assessment of maps was done using cross validation and three methods including: Root Mean Squared Error (RMSE), Mean Bias Error (MBE), and Mean Absolute Error (MAE). Results showed that the exponential model was the best-fitted variogram model and the data had high spatial structure. Among spatial statistical methods, the ordinary and universal co-kiriging were the best methods for the three parameters studied. According to the maps produced from these methods, A. fragrans is mostly distributed on the central and northeast parts and in low altitudes. Overall, spatial statistical techniques could be applied to zone the perennial key species of rangelands with proper sampling units.

The purpose of present study was to investigate the relationship between density, cover percentage, and biomass of Daphne mucronata and the most important environmental factors including soil physicochemical properties and topographic characteristics. For this purpose, in three areas (area with high, medium and low coverage of Daphne mucronata), four transects of 100 m length were located on the slope. Density with the Point-Centered Quarter Method; coverage percentage through linear transect method and biomass via cutting and weighing method were estimated. Soil samples were systematically taken along each transect at the depth of 0-10cm and 10-30 cm in each area. Once in the laboratory, some soil physical and chemical properties such as soil texture, pH, EC, percentage of organic matter, and total nitrogen were measured. The relationships between plant measurements of Daphne mucronata and soil properties and topographic characteristics were investigated using multiple regression analysis. The results demonstrated that along topographic characteristics, the slope of 60-70% and the height of 1850 to 2050m had the most influence on the density and cover percentage of Daphne mucronata, likewise the slope of 80-90% and the height of 2050 to 2350m had the most influence on its biomass. According to the results, this species mainly appeared in the southwest directions, on the slope of 60-90 %, at the height of 1850 to 2350 m above sea level, in clay loam soils with a pH of 6. 58 to 7. 25 and low salinity.

This study was conducted to evaluate the nutritional value of Alhagi camelarum and Halocnemum strobilaceum silage mixed with Hordeum vulgare seeds and molasses. After collecting and crushing plant samples, they were ensiled in a randomized complete block design with four treatments and three replications at different ratios of dry matter weight. After 28 days of silage, the nutritional value of these mixtures was determined by chemical and gas production methods. To determine the consumption ratio, three one-year-old sheep and goats were used. The results indicated that the treatment containing 50 % H. strobilaceum, 10% barely, 30 % A. camelarum and 10 % molasses had the most nutritional value, so that the highest values of OMD, SCFA, ME, DOM, and NEL in gas production method and CP, ASH and FAT in chemical method were recorded for this treatment. The highest consumption ratio was recorded for the mixture containing 50% H. strobilaceum, 20% barely, 20% A. camelarum, and 10% molasses. Overall, since H. strobilaceum and A. camelarum, accounting for 80% of this mixture, grows wild in nature, this silage could be recommended as a suitable mixture in saline and rocky lands after supplementary studies.

Desertification is defined as rapid change in vegetation cover, plant community composition, hydrologic conditions, soil properties, or climate conditions, which results in an overall loss of ecosystem services and poses serious threats to sustainable livelihoods. The process represents one of the most threatening environmental hazards due to the large amount of people and land at risk. Therefore, this research was aimed to modeling of desertification and zonation of Haj Ali Gholi Playa according to the climate parameters such as temperature, rainfall amount, evapotranspiration potential, number of sunny hours, climate condition, drought (aridity), and maximum prevailing wind speed, using GIS technique and statistical methods. The modeling was performed using stepwise multiple regression analysis. According to the results, maximum significant relationship was found among desertification classes and dry zone with a determination coefficient of 0. 999 and STD error of estimate of 0. 033 (α ≥ 0. 01). Other results are included the zonation map of desertification in the study area from very high zone to no-desertification zone, so that, the very high desertification zone is included about 679. 75 km2 (%92. 66) of present land degradation and has the possibility of increasing up to 5668. 11 km2. In addition, the high desertification zone, covering about 5. 22 km2 (%0. 44) of present land degradation, can develop to 933. 86 km2. The obtained results from validation test of the model show the descending trend of accuracy assessment index from the very high desertification zone to the no-desertification zone, indicating the necessary accuracy of the model.

This research was aimed to modeling the habitat suitability for plant species in southern rangelands of Golestan province by ENFA method with Biomapper software. For this purpose, the spatial data of species presence and environmental conditions were used to identify the suitable sites for the study species and their habitat requirements. For vegetation sampling in each vegetation type, three 50-meter transects were established, along which measurements were performed within 10 plots with five-meter intervals. The plot size was calculated to be 1m2. In each vegetation type, soil sampling was done at 0-30 cm depth. Then data were entered to the Biomapper software and the middle algorithm and harmonic algorithm were used to produce the habitat suitability map. The kappa coefficient was used to check the conformity of the predicted map with actual vegetation map. The kappa coefficient was calculated to be 0. 57, 0. 70, 0. 58, and 0. 50 for Artemisia aucheri, Festuca ovina-Astragalus gossypinus, Bromus tomentellus, and Bromus tomentellus-Festuca ovina, respectively. According to the obtained results, the most important environmental factors affecting plant species in the study vegetation types were as follows: clay content and slope (A. aucheri); sand content and altitude (F. ovina-A. gossypinus); sand content and northwest aspect (B. tomentellus); sand content, altitude and organic carbon (F. ovina-A. gossypinus). The models developed in this study can be used to identify suitable areas for range improvement practices.

Determining the allowable use is one of the basic requirements to calculate the grazing capacity in range management plans. In this study, initially, the range condition and trend of vegetation types and the suitability class of soil susceptibility to erosion were determined. Then, the allowable use was determined for each vegetation type regarding the mentioned indices and that the allowable use in each climate region is recommended differently to maintain rangeland health. The maximum allowable use for the study rangelands, representing mountainous semi-steppe, was calculated to be 40%. The allowable use of other vegetation types was determined regarding the limitations of indices. According to the results, the allowable use was calculated to be 40%, 30%, 25%, and 15% for 21. 4%, 13. 6%, 19. 3%, and 27. 6% of the study rangelands, respectively. Around 18. 1% of the study rangelands were classified as non-utilizable due to the poor range condition, negative trend and the soil susceptible to erosion. In most areas, poor range condition and negative trend acted as a limiting factor and led to a low estimate of allowable use. Therefore, care must be taken in selecting the indices affecting the allowable use of range habitats and in addition to plant health, range condition and trend as well as ecosystem health should be considered.

The use of unconventional waters in the agricultural lands not only reduces the environmental hazards but also increases the productivity. This research was aimed to assess the effects of wastewater, saline water and brackish water on some soil properties including organic matter, bulk density, and electrical conductivity. Therefore, five study sites were selected. The treatments consisted of control, irrigation with saline water, brackish water, and wastewater as well as mixed irrigation of wastewater and saline water. Five profiles were dug in the study sites. In each profile, two samples were taken from two depths of 0-30 cm and 30-60 cm. The results showed that irrigating with wastewater led to improved soil properties in terms of organic matter and bulk density, as compared with other treatments. There was no significant difference in pH among all treatments. However, the amount of Electrical Conductivity of saline water in surface and deep layers of soil was 17. 57 ds/m and 5. 5 ds/m, respectively. This large difference between the two depths in saline water treatment represents the EC downward trend from surface to depth. This trend was constant for the brackish water and wastewater treatments.

In this study, the impact of climatological parameters and land use on water yield of the watershed was investigated. Therefore, the trend of climatological parameters (precipitation and temperature) and stream flow discharge were studied monthly, quarterly and annually at the stations located inside and near the watershed using Mann-Kendall test. To evaluate the land use changes and its impact on run-off, the Helsel and Hirsch method was employed. In this method, the impact of precipitation (as exogenous variable) and the serial correlation of run-off data were removed, and again the trend test was implemented on the remaining logarithmic data of run-off (adjusted). In addition, the variations of snow line during the last 20 years were investigated to determine the role of climatological variation on watershed landscape. The results revealed that precipitation and mean temperature parameters over monthly, seasonal, and annual scales as well as run-off data after removing the precipitation impact and serial correlation between data had no significant trend. Therefore, it is concluded that climatological parameters and land use changes had no noticeable influence on the surface water of the watershed. Our results clearly showed that the Helsel and Hirsch method could be used in other regions since it could remove the effects of precipitation and its variation carefully. Moreover, the snow line of the study watershed showed no significant trend. According to the minimum and average snow line height, a high annual fluctuation was observed in the watershed during the study period. These factors may be the main reasons for non-significance of stream flow discharge and run-off height trends.

The aim of this study was to evaluate the production characteristics and the consumption rate of dominant forage species in different phenological stages. The study was conducted in Sabalan, Ardebil Province for four years. In this study, for each species, four average individuals were selected and marked inside and outside the exclosure, and the production was harvested. The total forage production and consumption was calculated using the production and density data of average individuals in the exclosure. In order to assess the effects of year and months of harvesting on the production and consumption of the study species, the data were analyzed by combined analysis of variance in a completely randomized design using SAS software. Mean comparison was performed by Duncan's test at 5% level for the effects of year, species and month on forage production and consumption. According to the results, a significant difference was found among the species in terms of production and consumption in the months of growth season and grazing period, as well as the study years. The total forage production of plants was different among the study years. The highest and lowest forage production (1971. 19 and 1635. 35 kg/ha) were recorded for the years 2010 and 2008, respectively. In addition, the highest and the lowest forage consumption (with 86. 72 and 67. 71 kg/ha had) was obtained in the years 2008 and 2009, respectively. Since the interaction effect of year and month was significant for most of the species, it can be concluded that forage production and consumption are affected by the year and its prevailing conditions.

The present study was conducted to evaluate drought stress and subsequent recovery on growth and biochemical changes of three Atriplex species. The study was performed as factorial based on completely randomize design with six replicates. The treatments included three Atriplex species (A. lentiformis, A. leucocalada and A. canescence) and four irrigation regimes (100 as control, 75% FC as light stress, 50% FC as severe drought, and no irrigation). The results showed that light and severe drought caused a significant reduction in growth of all three Atriplex species, and no irrigation treatment caused the loss of A. leucocalada and A. canescence. The recovery could offset the loss partly in all three species, especially A. lentiformis, so that there were no significant differences between control and 75% FC treatments. Tissue moisture percentage showed no significant difference in control, 75, and 50% FC. In A. lentiformis, no irrigation treatment caused a significant reduction in moisture percentage; however, recovery offset a considerable part of this loss. Water deficit treatments (75 and 50% FC) increased the activity of catalase, peroxidase and superoxide dismutase. The highest activity of all four enzymes was obtained in A. lentiformis. Generally, drought stress, depending on stress levels, reduced the growth and increased the antioxidant enzymes in all three-study species, and recovery, depending on species and stress levels, could offset a part of this loss. A. lentiformis showed the highest drought resistance and higher recovery ability, which might be due to the higher activity of antioxidant enzymes.

Soil is a suitable bed for plant growth and development of vegetation, so that if it is not conserved, it will result in the nutrient deficiency, soil erosion and degradation of natural resources. In this research, the spatial variability of some chemical and physical properties of soil was investigated in different vegetation covers (minimum, moderate and maximum) and different grazing intensities including reference area (light grazing), key area (moderate grazing) and critical area (heavy grazing) in the winter rangelands of Nasho, Mazandaran province. Soil samples were collected from 0-30 cm depth according to a systematic grid (30×30 m) and then transferred to the laboratory. Soil chemical and physical properties including acidity (pH), Electrical Conductivity (EC), caco3, bulk density, particle density, total phosphorus, total nitrogen, available potassium, organic matter, initial moisture content, percentage of clay, silt and sand, sodium, calcium, and magnesium were measured in laboratory. In addition, soil surface resistance was measured in the field with a portable penetrometer. The results of statistical analysis showed that different grazing intensities had significant effects on organic matter, available potassium, pH, EC, caco3, calcium, bulk density, initial moisture content, and surface resistance of soil. Different vegetation covers had significant effects on silt percentage, organic matter, pH, EC, calcium and initial moisture content of soil.

This research was aimed to investigate the effects of exclosure on species diversity changes under grazing and exclosure conditions in the northeast rangelands of Delfan County, Lorestan province. For this purpose, 120 quadrates of 1*1 m2 were established in a randomized-systematic method along 12 transects of 100 m length at four altitude classes (three transects on each altitude class). In each quadrate, the list of species, density, the percentage of canopy cover, litter, stone and gravel, and bare soil were recorded. To evaluate the numerical indices of diversity, Ecological Methodology software (Ver., 6. 2) was used and numerical indices of diversity and evenness were calculated. Data analysis was performed in SPSS software (Ver. 18). According to the obtained results, a number of 132 species were identified, belonging to 30 families and 104 genera, of which 124 and 108 species were recorded in the rangelands under exclosure and grazing conditions, respectively. Our results clearly showed higher numerical indices for richness, evenness, and species diversity under exclosure as compared with grazing condition. The canopy cover percentage of perennial grasses and forbs as well as litter percentage was higher inside the exclosure while the canopy cover percentage of annual grasses and shrubs as well as bare soil percentage was lower as compared with outside the exclosure. The density of perennial grasses and forbs increased, while the density of shrubs decreased inside the exclosure. In addition, a higher production was obtained from the rangeland under exclosure condition.

It is very difficult to provide water for irrigating plants in arid areas. However, range and desert plants are usually drought tolerant and may need no additional water for growth. Therefore, determining the best cultivation method (irrigation or rainfed) in terms of seed production economy is an important issue for seed producers. This research was aimed to compare the seed yield of three rangeland shrubs, Salsola rigida, Kochia prostrata and Eurotia ceratoides under rainfed and irrigation regimes, at the Seed Production Station of Sharak-Imam Neyshabur. For sampling, five belt transects (30 m length and 50 cm width) were randomly established, along which the number of plants established were counted for each species. Forage production was estimated by cut-and-weight method. The highest seed yield was recorded for Salsola under irrigation (1074 kg/ha) and the lowest for Eurotia under rainfed cultivation (209 kg/ha). Irrigation regime increased plant density, seed yield, seed number, and forage yield in Eurotia; plant density and forage yield in Kochia, and plant density in Salsola. Accordingly, for seed production in Shahrak Imam, we suggest sowing Eurotia under irrigation, but Kochia and Salsola need no watering after the initial establishment.

There are various methods to measure the utilization of grasses that each of these methods has its own advantages and disadvantages. The use of utilization gauge for grasses and grass-like species is one of these methods. This research was aimed to investigate the efficiency of utilization gauge in determining the utilization rate of native grasses in Iran. Thus, the utilization rate of Agropyron cristatum and Stipa barbata was measured by utilization gauge method, and the conformity of results with the weight ratio method (control) was assessed by linear regression. Since the utilization scales are prerequisite to the use of utilization gauge, which currently do not exist in our country, first these scales were developed. For this purpose, 30 plant individuals were sampled, of which 25 individuals were used to provide utilization scales and five individuals were used to evaluate the conformity of the two methods. According to the results, the two methods showed good conformity, so that the utilization gauge could be used to estimate the utilization of grasses. Since this method is rapid, non-destructive, and cheap, the use of utilization gauge is recommended to estimate the utilization rate of native grasses.

The use of nature in a way that is least harmful to the environment and the best efficiency is achieved for humans is possible when all factors and phenomena involved in environment are considered in the planning of land. For this purpose, this research was aimed to assess the ecological capability for the rangelands of Lar city in the Baluch region using the Analytic Hierarchy Process (AHP) based on the principles of land use planning. Initially, the information layers including vegetation, climate, geology, landform, soil, and erosion were prepared in Arc GIS. Then, the weighting of evaluation criteria was performed in the Expert Choice software based on the Analytic Hierarchy Process (AHP). In the next step, the weights of evaluation criteria were extended to the layers and analysis was performed in Idrisi. According to the obtained results, the ecological capability of the study rangelands for range management development was classified into five classes, namely high suitable (78. 5 ha), suitable (321ha), moderately suitable (71. 25 ha), low suitable (172 ha), and not suitable (1445. 4 ha), respectively. In addition, our results showed that attention to climatic and edaphic conditions as well as socio-economic issues are important and necessary for the implementation of any range management plan in this region.

This research was aimed to study the effects of elevation and aspect on diversity components (alpha, beta and gamma) using additive partitioning in the Geno Mountain. All plant species were listed in nine elevation zones (400-1050 m a. s. l. ) in southern and eastern aspects of Geno. The cover percentage was measured using five plots of 4m2 (in total 90 plots) in each elevation zone. Total plant species diversity (γ r) was partitioned into additive components within plots (α 1) and between plots (β 1) and among elevation zones (β 2) and among aspects (β 3). The results showed that β 3 diversity (72. 36%) and β 1 (8. 19%) had the highest and lowest contribution to the total diversity (γ r), respectively. The β 3 and α 1 values were higher and lower than the expected values, respectively, indicating the non-random distribution of plant species. The lowest observed percentage and expected values at the alpha level were recorded for both southern and eastern directions. In addition, the lowest observed values at the alpha level were recorded for the southern (5. 95%) and eastern (5. 73%) directions. Generally, beta components had a higher percentage, whose values were higher than that of the expected values. On the other hand, the alpha component in eastern and southern directions was lower than expected values. The results showed that the highest Shannon index (1. 72) and richness (22) were obtained at elevations of 1200-1600 m a. s. l. and 1600-2050 m a. s. l, respectively. According to the results of this study, it is suggested that the regional scale (whole area) should be taken into consideration to protect and enhance the diversity.