فهرست مطالب

ECOPERSIA - Volume:7 Issue:1, 2019
  • Volume:7 Issue:1, 2019
  • تاریخ انتشار: 1397/11/18
  • تعداد عناوین: 7
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  • S.D. Mirhasannia , M. Akhoundian*, H. Taghavi Pages 1-11
    Aims
    Green algae (Chlorophyta), as a diverse group of algae, has almost omnipresent distribution in the Caspian Sea and plays an important role in ecosystem functioning. The aim of this study was to investigate the spatial and temporal distribution and biomass trend of planktonic green microalgae (Chlorophyta) in southeast of the Caspian Sea.
    Materials & Methods
    This experimental study was performed by sampling water from south of the Caspian Sea in Mazandaran province during the winter 2015 and summer 2016. Water sampling was done along two half-lines perpendicular to the estuaries of "Tajan" and "Babolrood" rivers in 8 stations and 4 depths (less than 1, 5, 10, and 20 m) in the euphotic zone, at 8 stations along the linear transects. Settlement method was applied to the preserved samples in formaldehyde 4%, in order to the qualitative and quantitative analysis of phytoplankton. The biomass of Chlorophyta was calculated, using the geometric shape method. The data were statistically analyzed, using PRIMER 6 and SPSS 19 software and the diagrams were drawn by Excel 2013.
    Findings
    Of total 29 identified Chlorophyta species, 28 species were present in the summer with the highest abundance of Chlorella sp. (1395×105±671×104 N/m3) and, 19 species were observed during the winter, with the highest abundance of Binuclearia sp. (456×105±155×104 N/m3). Binuclearia sp. also showed the highest biomass in both seasons.
    Conclusion
    The diversity of Chlorophyta is influenced by seasonal variations. Estuaries are the richest stations in terms of abundance and biomass of planktonic Chlorophyta in summer.
    Keywords: Phytoplankton, Chlorophyta, Distribution, Biomass, Caspian Sea
  • R. Dehghani Bidgoli * Pages 13-20
    Aims
    The use of plants for treatment and food returns to ancient times. This study was conducted to examine the essential oil composition and antioxidant activity of the essential oil of Artemisia sieberi Besser at 3 phenological stages and effect of grazing livestock on these properties.
    Materials & Methods
    For this purpose, 5 shrubs from two sites (under grazing site and enclosure site) were selected randomly at 3 phenological stages. In laboratory operations, essential oil of the species was extracted in by SDE method.
    Findings
    The results of GC/MS analysis indicated 45 compounds for grazed site with essential oil content 98.73%, and 42 compounds for enclosure site with essential oil content 98.54%. Also, α-tujune (21.63%), α-Pinene (19.53%), and Camphene (10.34%) were the main compounds in the enclosure site and α-tujune (23.70%), α-Pinene (20.33%), and Camphene (12.60%) were the main compounds in the grazed site. The results of screening antioxidant activity using two assays (DPPH and β-carotene-linoleic acid) showed that the free radical scavenging activity of essential oil (IC50 µg ml-1) in the first phenological stage (vegetative stage) was more than other phenological stages in two sites. Also, the inhibition of essential oil in the grazed sites had a significant difference with essential oil's inhibition in the enclosure site.
    Conclusions
    Effect of grazing on the composition and properties of the essential oil of this species can be considered in the planning of livestock grazing management. We wish our future research on this plant leads to the finding of new natural antioxidant compounds.
    Keywords: Essential Oil, Phenological Stages, GC-MS, Antioxidant Activity, Artemisia
  • M. Sharifi, Rad * Pages 21-27
    Aims
    The aim of this study was to determine the effect of drought stress induced by using polyethylene glycol (PEG), heavy metals (Cd and Ni), and salinity (NaCl) on germination and seedling growth of Sinapis arvensis, an important medicinal plant in the Brassicaceae.
    Materials & Methods
    The Sinapis arvensis seeds treatments contained i), control ii), PEG (5%, 10%, 15%), iii) NaCl (50, 100, 150 mM), iv) Cd+2 (50, 100, 150μM), and v) Ni+2 (50, 100, 150μM). The experiment used a randomized complete block design with 4 replicates per treatment. The experiments were performed in a programmed incubator at 25±2oC. Seed germination was recorded every day for 16 days. The root and shoot lengths of seedlings were measured after 16 days of incubation. Then, the seedlings were dried and root and shoot dry weights were measured.
    Findings
    The results showed that germination percentage reduced with increasing concentrations of the tested factors. The maximum germination (97%) was observed in PEG (5%) and the minimum germination rate was recorded in NaCl (150 mM) with 41%. The maximum of root and shoot lengths were recorded in PEG (5%) and Ni (100μM) with 59 and 73 mm, respectively. Results showed that the maximum root and shoot fresh and dry weights were recorded at Ni (100μM) treatment.
    Conclusion
    Understanding plant responses to environmental stresses can help select suitable plants in order to obtain sustainable products. Overall, we can conclude that under aforementioned treatments, the root growth of S. arvensis was more affected than the shoot growth.
    Keywords: Germination, Seedling Growth, Abiotic Stress, Sinapis Arvensis, Medical Plant
  • F. Faraji , A. Alijanpour , E. Sheidai Karkaj*, J. Motamedi Pages 29-37
    Aims
    In recent years, global warming has increased the importance of carbon sequestration. The present study was conducted to survey the effect of banqueting and fire on soil organic carbon (SOC) sequestration in Atbatan rangelands of Bostanabad District.
    Materials & Methods
    For this purpose, using systematic-random strategy, composite soil samples were taken from fire happened 2 years ago (in 2 aspects of east and west), banqueting constructed 25 years ago (in 2 aspects of north and south), and control sites. The SOC was measured and results were analyzed, using two-way ANOVA.
    Findings
    On the contrary of interaction effect, the main effects of aspect and fire were significant on SOC. The SOC of the control site with 28.9 t/ha was higher than the fire site with 21.76 t/ha. The average SOC in the eastern aspect was higher than the western aspect as such the average amount of SOC in western and eastern aspects were 28.94 t/ha and 21.72 t/ha, respectively. Banqueting had an increasing significant effect on SOC, as such SOC of the treatment site was 34.47 t/ha compared to the control site with 22.21 t/ha. The SOC in the northern and southern aspects was not significantly different, and the SOC of southern and northern aspects equaled 28.45 t/ha and 28.23 t/ha, respectively.
    Conclusion
    In conclusion, according to the results of the study, the occurrence of fire in rangelands can reduce the amount of SOC. The rangeland banqueting increases the amount of SOC in both aspects.
    Keywords: Carbon Sequestration, Soil, Banqueting, Fire, Atbatan Rangelands
  • E. Jafari*, A. Karimi , A. Hatami Pages 39-46
    Aims
    Floristic survey of an area is a useful tool for identifying the biodiversity, particularly endemic, resistant, and endangered species. In the current study, plant species were classified to describe the flora of Galehdar watershed in Southern Fars Province.
    Materials & Methods
    The environmental data including climate, geology, and topography characteristics were obtained from Iran Meteorological Organization (IMO), Geological Survey & Mineral Explorations of Iran (GSI), and National Cartographic Center (NCC), respectively. The specimens of the study area were collected, identified, and classified according to Raunkiaer's method and life-form class.
    Findings
    The flora of study area includes 164 species belonging to 129 genera and 55 families, which most frequent species belong to Asteraceae (25 species), Papilionaceae (21 species), and Poaceae (11 species).
    Conclusion
    The chorological studies indicated that 57.9%, 12.8%, and 29.3% of species belong to Irano-Turanian, Sahara-Seindian, and Irano-Turanian, Sahara-Seindian zone, respectively.
    Keywords: Chorology, Flora, Plant Species, Life Form, Fars Province
  • M. Afshari , S.S. Hashemi*, B. Attaeian Pages 47-57
    Aims
    Todays, the change of range land to agricultural uses by unplanned and improper locations of water supply wells would be led to sever reduction of ground water level and subsequently fully land degradation. However, the aim of this study was to investigate the effect of land use change on soil physical, chemical, and mineralogical properties.
    Materials & Methods
    In this study, 9 soil profiles in Kangavar plain with range and different arable land uses were dug and described. Some properties of soil samples were determined, then, pedons classified to Inceptisols, Entisols, and Mollisols orders.
    Findings
    The result showed that with land use change from range land to agriculture, content of soil clay reduces (from average 47.6% to 41.4%). With land use change of range to cropland properties including pH, organic matter and calcium carbonate equivalents contents decreased. The amount of soluble potassium in the surface horizons in range lands was more than arable land. In the cropland pedons, the amount of soluble sodium reduced compared to rangeland pedons. The results showed that land use change had no effect on clay minerals type, but changed those value. According to the results, in range land, illite and vermiculite percentage were greater than crop land soil pedons. The smectite content in arable land use more frequency than range land (data have significant difference at p< 0.05 level).
    Conclusion
    It was concluded that long-term agriculture in study area induced to sever reduction of nutrient and consequently caused to soil degradation in whole plain.
    Keywords: Macro-nutrient, Clay mineral, Soil texture
  • M. Zamanpoore*, M.R. Daremipouran , M.R. Ghaed, Abdi , N.Kh. Ahmadi Pages 59-67
    Aims
    The ecology of Maharlu Lake is of great importance, especially in relation to the continuous addition of a reasonable volume of municipal and industrial effluents to it. To improve our knowledge about lake's ecology, mineral nutrients and heavy metal concentrations, among some other physical and chemical factors, are investigated.
    Materials & Methods
    3 stations were selected in the lake and critical factors were measured monthly from January 2000 to December 2001. Main physical and chemical properties included temperature, pH, dissolved oxygen, CO2, conductivity, salinity, dissolved solids, and concentration of major ions, including carbonate and bicarbonate, phosphate, nitrite and nitrate, calcium and total hardness, chloride, and alkalinity, and heavy metals as Co, Cd, Pb, and Hg.
    Findings
    Averages of pH, dissolved oxygen, salinity, electrical conductivity, and dissolved CO2 were 7.9, 2.9mgL-1, 290gL-1, 375mscm-1, 342mgL-1, and 63mgL-1, respectively. The highest concentrations of heavy metals were 23μgL-1 for As, 303μgL-1 for Co, 970μgL-1 for Cd, 8510μgL-1 for Pb, and 25μgL-1 for Hg.
    Conclusion
    Essential factors of the lake are in accordance with the soil of the catchment area, but they are in many cases altered under local attributes like precipitation, irradiation, evaporation, and deposits, as well as living elements of the lake’s ecological network, as the consequences of activities of bacteria in biological processing of nitrogen and phosphorus, etc. After this research, Maharlu Lake was totally dried up, never filled again. So, the results of this investigation can be regarded as the last record of the lake situation prior to its current complete drought condition.
    Keywords: Saline Lakes, Nutrients, Heavy Metals, Pollution, Fars Province