Hosein Tavakoli Neko; Schahram Banedjschafie; Abbas Pourmeidani
Volume 31, Issue 1 , June 2024, , Pages 1-14
Abstract
Background and objectivesThe vast country of Iran, due to its location in the arid region of the earth and the lack of rainfall, has suffered from drought and groundwater depletion. The reduction of precipitation and soil moisture has a great effect on soil vegetation. The use of various types of moisture ...
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Background and objectivesThe vast country of Iran, due to its location in the arid region of the earth and the lack of rainfall, has suffered from drought and groundwater depletion. The reduction of precipitation and soil moisture has a great effect on soil vegetation. The use of various types of moisture absorbent materials that reduce water consumption and increase the time of plant access to water in the soil plays a big role in water conservation. Plantbac panels are made from cellulose waste and can be used to increase the water retention capacity of the soil in dry areas, especially in desert areas. MethodologyIn order to investigate the effect of Plantbac panels on the amount of water consumption and growth of Atriplex plant, the research was carried out in the area of Hesarsokh located ten kilometers north-east of Qom city for three years (2019-2021). The experiment was carried out as split plots in the form of randomized complete blocks including 12 plots in three replications. The main plot included irrigation treatments at intervals of 10 days (control) and 20 days, and the sub-plot included two treatments of using and not using Plantbac panels (control). To investigate the effect of Plantbac panels on seedling growth at the end of each growing season in each year, traits including: survival, height and crown diameter of the seedling were measured and compared with the control of the same treatment. Statistical analyzes including minimum and maximum traits, standard deviation, simple variance analysis of variables, compound analysis, comparison of averages with least significant difference (LSD) method for seedling height growth and crown diameter growth traits were performed. ResultsThere was no difference in seedling survival in the treatments of using Plantbac and control in irrigation with a 10 days interval. While in the treatment of Plantbac panels and the control, 5% of the seedlings were dried, and in the treatment of using the Plantbac panels, 21% and 40% of the seedlings were seen in the control. Combined variance analysis showed that the simple effects of using Plantbac panels, year and the interaction effect of irrigation in the year on the height growth of Atriplex were significant (P≤0.01). Also, the effect of irrigation treatments, the use of Plantbac panels, the mutual effect of irrigation in the year and the effect of the year had a significant difference in the diameter growth trait of the crown of Atriplex seedlings (P≤0.05). The comparison of the average traits showed that the Atriplex seedlings in the "3rd year × 20 days irrigation interval" had the highest height 6.32 cm, and in the "1st year × 20 days irrigation interval" with 9.75 cm, had the lowest height growth. Also, Atriplex seedlings had the highest crown diameter growth in the "3rd year × irrigation interval 10 days " with 22.11 cm growth, and the lowest crown diameter growth had in the "2nd year × 20 day interval irrigation" with 17.33 cm. ConclusionThe results of the research showed that the effect of Plantbac panels on the traits indicating the growth of Atriplex is effective. The use Plantbac panels reduces losses in the survival of Atriplex seedlings. In other words, the use of Plantbac panels can have an effect in reducing the losses of Atriplex seedlings in saline lands. Also, the height growth of Atriplex in the treatment of using Plantbac panels was higher than the control. The general results of the research showed that the use of Plantbac panels can have an effect in reducing the losses of Atriplex in saline lands. Also, the diameter and height growth of Atriplex in the following years of planting was higher than the first year, which can be due to the possibility of establishing and improving the soil conditions for plant growth in the following years after planting as a result of using Plantbac panels.
Mohammad Sadegh Kahkhakohan; Abolfazl Rajbar Fordoie; Seyed Hojat Mousavi; Abbasali vali
Volume 26, Issue 3 , September 2019, , Pages 754-771
Abstract
Drought and its effects is one of the world's major concerns. As one of the countries in the dry belt of the earth, Iran has always been and is facing environmental issues and natural hazards caused by drought. Therefore, this study aimed to monitor the aridity in Sistan and Baluchestan using remote ...
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Drought and its effects is one of the world's major concerns. As one of the countries in the dry belt of the earth, Iran has always been and is facing environmental issues and natural hazards caused by drought. Therefore, this study aimed to monitor the aridity in Sistan and Baluchestan using remote sensing data and geographic information system techniques for over a period of 15 years (2015-2000). In this regard, the MODIS satellite images from 2000 to 2015 were analyzed by applying the yearly Precipitation Condition Index (PCI) and Standardized Precipitation Index (SPI). Then, the drought changes were evaluated using supervised classification method and difference images. The results showed that the years 2007 and 2001 with an area of 157383.06 and 306.05 km2 had the highest and lowest levels of precipitation, and also with an area of 49511.1 and 69233.83 km2 had the minimum and maximum level of drought, respectively. The most severity change of drought has been in time for the 2002-2001 period and the place also belong to parts of Khash, Iranshahr and Sarbaz who takes 194302.93 km2 of the province. Finally, the general trend of changes in precipitation and drought is decreasing and increasing, respectively, requiring the major planning of resources conservation and risk and crisis management to rehabilitate and maintain the ecosystem of arid regions.
Abolfazl Rahmatizadeh; Mohammad Jafary
Volume 21, Issue 3 , December 2014, , Pages 496-506
Abstract
Due to the population growth and human intervention in nature, desertification has increased drastically. The Masileh watershed is located in the southern highlands of central Alborz. In this study, vegetation condition, the volume of water entering the area, soil chemical characteristics, and ...
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Due to the population growth and human intervention in nature, desertification has increased drastically. The Masileh watershed is located in the southern highlands of central Alborz. In this study, vegetation condition, the volume of water entering the area, soil chemical characteristics, and agricultural production statistics of the region were examined and compared before and after the construction of dams during two periods with an interval of five years. Results showed that since the construction of 15- Khordad dam in 1995, the volume of water entering the Masileh plain has reached zero.The hydrograph study showed that the groundwater level of Masileh plain has dropped on average five meters/year. Due to the lack of flood entering and soil washing, the salt concentration of soil surface layers in most vegetation types has increased. Due to the lack of root access to water, the canopy cover percentage in halophyte vegetation types with shallow roots such as Aeloropus litoralis and Cyperus sp has been reduced up to 100%, and new species such as Halocnemum strobilaceum and Halostachys caspica have been replaced. In terms of agriculture, significant changes have occurred in the composition and type of agricultural crops. Our results clearly showed that the Masileh plain is turning from a productive agricultural area into a real desert.
Abbas Kazempour; Ali ashraf Jafari; Mehrnaz Riasat
Volume 18, Issue 2 , September 2011, , Pages 307-321
Abstract
The genus of Elymus is of important grasses for forage production and soil and water conservation in Iran's rangelands.It has high preference value for livestock grazing because of the high production and high acceptability. Important species of this genus show different tolerances to drought.In order ...
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The genus of Elymus is of important grasses for forage production and soil and water conservation in Iran's rangelands.It has high preference value for livestock grazing because of the high production and high acceptability. Important species of this genus show different tolerances to drought.In order to determine the reactions of 14 accessions of Elymus hispidus and Elymus pertenuis to drought stress, a factorial experiment was conducted using completely randomized design with three replications in a standard germination test in 2008, Shiraz, Iran.Polyethylene glycol 6000 was used at 4 levels (0, -8/0, -9/0- and -1 MPa) as different osmotic potentials.Data were collected and analyzed for germination percentage, speed of germination, root length, shoot length, seedling length, root / shoot length ratio, seedling weight and seed vigor index.The results showed significant differences among accessions, drought effects and interaction effects of accessions* drought for all the traits.However, there were no significant differences between means of two species for all traits except seedling weight.In both species, all traits except root / shoot length ratio were decreased by increasing osmotic potential. In contrast, means of root / shoot length ratio was increased by drought stress.The effect of drought stress was higher on shoot length than those for root length, indicating that the sensitivity to drought stress of shoot length was more than root length.The results showed that some accessions within E. hispidus species as (Yasoj , Eghlid and Brojen) showed the maximum drought resistance in most of the seedling attributes. According to the results of Probit analysis, LD50 were estimated as -0.72 and -0.81 MP for E. hispidus and E. pertenuis, respectively.