نشریه خشک بوم
سال یازدهم شماره 1 (بهار و تابستان 1400)

With the intensification of biodiversity decline and habitat loss due to destruction and fragmentation, scientists are looking for criteria for prioritizing wildlife habitats and expanding protected areas based on the high distribution and abundance of the species, especially indicator species. One of the Iranian middle-sized carnivores is Honey Badger with Afrotropical distribution the utmost spread of its northern dispersion reaches Iran. Its distribution and ecological information are scarce in Iran and in all its distribution range in the world. In this study, through gathering presence point data in Kerman province, potential habitats and effective biogeoclimatic parameters affecting the species distribution during the year were identified. The Maximum Entropy modeling approach was applied. According to the results, more than one-fifth of the province is suitable for the species. Most parts of the preferable habitats are in the western half of the province at an altitude of above 2000 meters above sea level. Habitats with the lower annual mean temperature and higher annual precipitation are more suitable for the species increasing annual mean temperature and dryness, the suitability of habitat decreases. Field surveys showed that damage to the poultries and beehives resulted in a high conflict between Honey Badger and local people.

Contamination with heavy metals such as leads resulting from human catastrophic excavation activities is one of the serious soil problems in arid and semi-arid region. So, remediation of these kinds of contaminations is one of priorites to protect the soil of these areas. In soil and sediment environments, the potential bioavailability and mobility of metals are predominantly regulated by adsorption/desorption reactions at the mineral-water interface. Although numerous studies have been devoted to understanding the adsorption of metals onto minerals, less is known about desorption processes, especially their kinetics, under the influence of organic ligands. In this study, desorption of Pb from montmorillonite (MMT) was studied as effected by biodegradable chelating ligands, i.e. methylglycine diacetic acid (MGDA) and glutamic-N,Ndiaceticacid (GLDA), at two concentrations (0.25 and 1.0 mM) were compared with that of ethylenediaminetetraaceticacid (EDTA). The results showed that Pb desorption was rapid, reaching equilibrium in a relatively short time (within 3 h). The degree of Pb desorption was proven to be governed by the presence and concentration of the chelating agents. The capacity of the chalants for removing Pb from MMT was in the order EDTA>MGDA>GLDA. Approximately 12%, 19%, and 23% of the sorbed Pb was desorbed by 0.25 mM of GLDA, MGDA, and EDTA, respectively. The corresponding desorptions in the presence of 1.00 mM of the same ligands were 47%, 59%, and 93%, respectively. Therefore, it can be predicted that the presence of biodegradable ligands, i.e. GLDA and MGDA compared to EDTA will create less mobility of Pb in the environment and consequently we will have less pollution in soil and water environments. Owing to soil alkalinity in arid and semi-arid region, it seems that using biodegradable ligands can desorbtion of lead from soil, minimizing the risk of under water contamination.

Intercropping of forage plants is considered as an effective startegy to achieve optimal yield and increase production in areas with water shortages. A field-based split plot experiment based on a randomized complete block design with three replications was conducted in Ashkezar research farm with the aim of evaluating the intercropping of millet and guar in improving physiological indices and forage yield. Irrigation intervals was considered as the main factor in three levels (irrigation at the time of discharge of 60, 70 and 80% of field capacity) and the cropping system was considered as the sub-factor in three levels (sole cropping of Millet, sole cropping of Guar, and intercropping of Millet and Guar). The intercropping system was implemented as row intercropping pattern with a replacement series design. Results showed that the amount of ionic leakage increased and the relative content of relative water content decreased when irrigation was delayed longer. The highest relative water content for Millet and Guar (70.3 and 78.4%, respectively) were obtained in intercropping system and their lowest relative water content (61.4 and 72.5%, respectively) were obtained in their sole cropping. The highest and lowest chlorophyll indices were observed in irrigation treatments at 60 and 80% of field capacity, respectively. The intercropping of Millet and Guar resulted in increased content of soluble sugar and proline and the highest forage yield compared to their sole culture, in all assessed irrigation intervals. Since intercropping system was shown to cause improved physiological indices of Guar and Millet, the consequent improvement of forage growth and yield could be expected. Overall, it can be concluded that intercropping system of Millet with Guar can significantly reduce the impacts of drought stress and can be considered as an effective management strategy in drought-prone areas.

In order to study of 13 primary chromosomal recombinant lines of hexaploid Tritipyrum in comparison with seven Iranian and two Afghan bread wheat cultivars and five promising triticale lines in hot and arid climate of Yazd as spring planting was carried out as a RCBD design with four replications on the farm of Yazd University. Some morphophenological traits were evaluated. The results showed that there was a significant difference between all studied genotypes in terms of all traits. The results of phenotypic correlation coefficient showed that heading and physiological maturity day had the highest negative and significant correlation with grain number and grain weight per spike. Tritipyrum cultivars with the highest average days to the physiological maturity, due to exposure to high temperatures, had a lower height than bread wheat and Triticale cultivars. La (4B/4D)/b showed the highest mean spike length. According to the type of cultivation and climate studied although Tritipyrum lines had the highest values for spike length, but they had the lowest values for the number of grains per spike and grain weight per spike. The results of principal component analysis showed that the first component determined 73% of the total variance. It can be concluded that the traits of stem elongation, heading, dough development and days to physiological maturity had the greatest impact on diversity. The genotypes studied in this study were classified into four clusters. In the first group, 12 Tritipyrum lines were included. Five Triticale lines and eight bread wheat cultivars were placed in the third group. The two-dimensional graph obtained from principal component analysis showed that the 12 Tritipyrum lines are superior to the other studied lines and cultivars in terms of phenological traits. Bioplate analysis, while explaining 82.2% of the total changes in the first two components, showed that the primary Tritipyrum lines include ma/b، St/b، La/b and (ka/b)(cr/b)f3 can be used as superior lines for some of the measured traits in future studies.

Due to the proximity to the water supply canal (Karun to Mahshahr) called Kut-Amir Canal and the availability of suitable water for irrigating the seedlings, the cultivated area was irrigated by surface irrigation and Furrow. The purpose of this study is to evaluate the trend of vegetation changes in during four consecutive years (2018-2021) and in two seasons in seedling cultivation areas was investigated. A total of five 100-meter transects, each 50 meters apart, were systematically established in the three selected areas. Around 30 fixed plots were installed along transects. In the two growing seasons of spring and autumn, the coverage of native species was recorded. The Simpson and Shannon, dominance, uniformity, and diversity indices were estimated using the PAST software. The results of one-way analysis of variance for the spring of 2018 to 2021 showed that there is a significant difference between the mean indices of coverage percentage, dominance, uniformity, Simpson and Shannon and Ghana diversity indices in consecutive years of harvest. The results of the Wilcoxon test showed that the indexes of species number, Simpson, Shannon, Evennnes, Manhinink and Margalf increased in the second year compared to the first year. Also, due to the fact that the sig rate is less than 0.05, there is a significant difference between the dominance indices, Simpson index and Shannon during July 2020 compared to 2019, but between changes in coverage percentage in the two there was no significant difference for consecutive years. The results of Duncan test showed that there is a significant difference between vegetation percentage and dominance index, Simpson and Shannon in spring (2018 and 2019) compared to (2020 and 2021) and is in two separate categories. Take. From the above observations and results, it can be concluded that in general, Shannon and Simpson diversity indices in the last year (2021) compared to the beginning year (2018) have increased significantly and this change is the result of increasing the uniformity and species richness in the area has been. The best options for improving the desert area above are Seidlitzia rosmarinus and Tamarix passerinoides. Also, the construction of Furrow along with seedling cultivation holes causes the accumulation of rainwater and the gradual emergence of other native species.

Climate change affects plant distribution in vulnerable ecosystems, such as gray almond (Prunus eburnea (Spach) Aitch. & Hemsl.). Gray almond is a member of the Rosaceae family and it has conservational, nutritional and endemic importance and widely distributed in arid and semi-arid regions of Iran. The main objectives of this study are modeling the habitat suitability of the gray almond species using the Maxent model and predicting the effects of climate change on its distribution as well as determining the contribution of environmental variables in modeling the habitat suitability. Evaluating the accuracy of Maxent model using the mean area under the curve index (0.94) indicates the excellent performance of this model. Results showed that the soil depth and the solar radiation layers with 35.4% and 27.3%, respectively, had the highest share of participation in modeling of the habitat suitability of gray almond species. Based on the map of habitat suitability in the current climatic conditions, it is predicted that the southern regions (Hormozgan, Bushehr and Fars provinces), south-west (Kohgiluyeh, Boyer-Ahmad and Chaharmahal Bakhtiari provinces) and southeast (provinces) Sistan and Baluchestan, Kerman and South Khorasan) have the potential of suitable environmental conditions to expand the habitats of this species. In order to evaluate the effects of climate change on the habitat suitability of this species, the Representative Concentration Pathway 8.5 (greenhouse gas emission scenario) related to greenhouse gas emission model CCSM4 in the 2080 was used. According to Maxent model, the area of suitable habitat of this species in the current climatic conditions is 862113 Km2. Predicted based on RCP 8.5 in 2080, suitable areas that this species will lose 36.14% and gain new suitable habitats as much as 8.9%. It is predicted that the area of suitable habitat areas of this species will decrease to 627273 km2 in the future. According to the results, it is necessary to have better ecosystem management of conservation and exploitation of gray almond habitats in future.

Reducing conflicts and wildlife damage are the most important aspects of their management. Different species of wildlife are in conflict with humans to meet their vital needs due to competition over food resources and habitat occupation. Considering the location and importance of Khojir National Park, the present study was conducted to develop a strategic management plan for the Hystrix indica in Khojir National Park with the aim of protecting and reducing conflicts of this species in the region. In the conflict management program of the mentioned species, appropriate strategies were selected based on internal factors (strengths and weaknesses) and external factors (opportunities and threats). Then, through classification, weighting and factor analysis using SWOT matrix, appropriate strategies were developed and pairwise comparisons of each of the sub-criteria and determination of weight and prioritization were performed using AHP method. In the next step, using the Quantitative Strategic Planning Matrix (QSPM), the feasibility and sustainability of the proposed strategies were evaluated and prioritized. According to the obtained results; Three strategies, including 1) Improving the quantity and quality of monitoring and updating the demographic and ecological information  of Hystrix indica with the help of the facilities of other organizations, 2) promoting and propagating of wildlife values and controlling the landuse change and habitat destruction and critique of superstitions, and 3) Reduction of damages in agriculture and horticulture with the cooperation of other active organizations in the region; were proposed as the most important management strategies to reduce the Hystrix indica conflicts in Khojir National Park.

One of the important requirements in crop planning in order to achieve high yield and optimum quality is evaluation of plant nutrition systems. The present study was conducted in order to evaluation using the sand and domestic manure levels on growth indices and allicene content in garlic (Allium sativium L.), as a factorial experiment in randomized complete block design with three replications, in University of Zabol Research Institute of Agriculture in 2018. Treatments, were considered in three levels including of: 0, 100, 200 (ton.ha-1) as the first factor, and cow manure in four levels including 0, 20, 25, 30 (ton.ha-1) as the second factor. Analysis of variance showed that levels of sand, cow manure and their interactions on plant height, leaf number, biological yield, economic yield, garlic diameter, allicin, leaf nitrogen, soil volumetric moisture, soil temperature, organic carbon percentage and the total irrigation were significant. The harvest index was significantly affected by simple effects of sand and cow manure levels, and the number of garlic and potassium leaves were affected by cow manure levels. The highest plant height (60.67 cm) and leaf number (18.33) were obtained from the treatment of sand (100 ton.ha-1)  in term of consumption cow manure(30 ton.ha-1). The most biological yield (13.14 ton.ha-1), economic yield (12.07 ton.ha-1), the highest diameter of garlic (12.65 mm) and the highest amount of allicin (6.26 mg.g-1), the least total irrigation (733.33 lit), The highest soil volumetric moisture (16.26%), the least soil temperature (33.83 °C), the highest organic carbon content (1.97%), were obtained from sand(200 ton.ha-1)  under cow manure(30 ton.ha-1). Since the goal of garlic cultivation is to achieve the best yield and yield components, therefore, (200 ton.ha-1) sand treatment under 30 ton.ha-1 manure is suitable for garlic cultivation in the region.

Drought monitoring using appropriate drought indices is of importance in water resources management, especially in arid and semi-arid regions. Therefore, choosing the suitable drought index and calculating the desired drought index appropriately is of considerable importance in the study of drought. This study is aimed to determine the appropriate statistical distribution to calculate RDI drought index in arid and semi-arid regions of Central Iran. For this purpose, 16 synoptic stations in Central Iran were selected. To calculate RDI, precipitation and potential evapotranspiration values are required. The FAO-Penman-Monteith method was used to calculate potential evapotranspiration. To select the most appropriate statistical distribution, 17 statistical distributions were used. RDI for each synoptic station was calculated annually by fitting to each of the 17 distributions, separately. Then, based on the AIC and BIC criteria, the best statistical distribution was selected to calculate RDI for each station. While based on the literature, it is recommended to calculate RDI by fitting the data to one of the Gamma or log Normal distributions, the results showed that in most of the studied stations, the log Normal and Gamma distributions are not the most appropriate distribution. However, according to the results, Gamma distribution was one of the top 6 distributions in all the studied stations. The results also showed that the difference of RDI values ​​calculated based on different distributions in dry and wet years are relatively significant, which shows the importance of choosing the appropriate statistical distribution. The fit of the studied distributions to the precipitation data at different stations showed that the Nakagami distribution presents the best performance. In case of potential evapotranspiration, different distributions provided the best fit at different stations.

Plant communities’ life and their distribution in a stand is affected by soil, climate and other environmental factrors. The purpose of this research was to investigate the soil condition and vegetation in three dominant stands of Tamarix ramosissima called Abyaneh, Chadegan watershed and Tang-e Bibi Zeinab in Isfahan province. After selecting the stands, sampling of plant was carried out as stratified random 400 m2 plots. According to the area of the studied areas and using the minimum area method, and the canopy cover of T.ramosissima was measured in each plot. 30 and 60 plots of 4m2 was used to calculate the vegetation cover percentage of companion species. Some physical and chemical soil factors including Ca+Mg، Na ،P ،K، SP ،OM ،CaCO3، CaSO4 ، BD، SAR، ESP، gravel and texture were measured. The simple correlation, regression and ordination were used to investigate the correlation between environmental factors and plant parameters. Results of the dendrogram showed that there is at least 60% similarity between the two habitats of Chadegan watershed and Tang-e Bibi Zeinab. Results of Pearson and Spearman correlation analysis showed that the total canopy area of the studied species is positively related with soil salinity factors and the total concentration of dissolved Ca+Mg with correlation coefficients of 0.76 and 0.75, respectively and is negatively related with clay percentage factors and organic matter with the correlation coefficients of 0.9 and 0.91, respectively. The results of ordination analysis diagram between plant parameters and environmental factors also showed that the habitat conditions of Artemisia aucheri are closely related to the habitat conditions of the T. ramosissima.

Hormoz Island is one of the most important islands with unique geomorphological capabilities in the Middle East due to the presence of beautiful salt domes and red soil, which unfortunately its attractions are not used in accordance with its ecological and environmental conditions. The curent study was conducted in the area of Hormoz Island with the aim of assessing the feasibility of economic and social development and protection of biologically sensitive areas of the island. For this purpose, the method of assessing ecological potential and land use planning with the principles of mapping in environmental units and using the system method in ArcGIS 9.2 software and slope, aspect, height, soil, vegetation, wildlife distribution and activity data layers Socio-economic conditions were integrated and a map of ecological potential and landscaping of Hormoz Island was prepared. According to the results, it was found that 5.5 square kilometers of the island area (equivalent to 13.1%) of urban development capacity, 7.8 square kilometers (18.6%) of the island area of mineral development capacity, 11.3 square kilometers of capacity Conservation (equal to 26.9%) and the remaining 41.4% of the island has a wide recreational capacity. Result showed that the Hormoz Island is not able to develop centralized recreation and it is necessary to consider the tourism program based on the physical development of Bandar Abbas and only for the implementation of one-day programs. Of course, with the organization of some rural houses.

In this research, the changes in the frequency intensity curve for the Zone No. 6 of Tehran municipality (Mehrabad synoptic station) under the influence of climate change were investigated by using the Abkhezr-Ghahreman relationship. The information related to the current research includes two categories: First category includes hourly rainfall data measured in order to derive IDF curves for the base period (1980-2020). The second category includes the predicted daily rainfall data for the near future (2021-2050) and the far future (2051-2100), which were obtained from the output of the LARS model. First, using EasyFit software, statistical analysis was done on the observational data and the best distribution (Gamble distribution) was selected and the corresponding IDF curves were extracted for different return periods. To extract the IDF curves under the influence of climate change, the general circulation model of the atmosphere HadGEM - ES from the series of CMIP5 models under RCP2.6, RCP4.5 and RCP8.5 emission scenarios was used. The results showed that the rainfall intensity in all rainfall interval duration and different return periods in all three scenarios have increased compared to the intensity duration frequency curve of the base period, and only for the near future (2021-2050) under the RCP 8.5 scenario, there is a decreasing trend compared to the base period will have. For example, interval duration of 4 and 24 hours for the return period of 10 years, the amount of precipitation intensity for the scenario RCP 2.6 and RCP 8.5 for the distant future (2051 -2100) is 7.05, 7.1 and 2.56, 2.58, respectively, while which for the base period (1980-2020) is 6.71 and 2.44, respectively, which indicates the increase in the intensity of maximum rainfall with the increase of the return period. It can be concluded that the maximum intensity of rainfall has increased in short-term time base and with the passage of time, the intensity of the maximum rainfall has decreased, and the IDF curves are affected by short-term rainfall.