Caspian Journal of Environmental Sciences
Volume:16 Issue: 2, Spring 2018

The main challenges facing the environment of the Caspian Sea include the water level rise, environmental pollutions, the entrance of exotic species to the Caspian Sea, loss of the flora reservoirs and eutrophication. These challenges forced the coastal states to conclude the Framework Convention on the Protection of the Marine Environment of the Caspian Sea in 2003. The long duration of time taken to adopt this convention and its two protocols, non-significance of two other protocols , the competition over energy issues in the sea and conflict of opinions concerning the legal regime have affected the level of cooperation among five coastal states in this field. This analytical-descriptive study seeks to answer this fundamental question: “What is the responsibility of the Caspian littoral states for environmental damage?” With the reviews, we can say that the Caspian Sea’s coastal states are responsible individually or collectively for their own omission and actions resulting in the environmental damages. They have to recover damages through the restitution or the compensation. It should be noted that the speed up of argument over the legal regime may reduce the environmental problems of the sea.

Due to the importance of Acer monspessulanum in Iranian mountain forests, a study was carried out to reliably estimate its woody biomass and growing volume via allometric equations. Four transects, five trees in each were chosen randomly. The characteristics of standing trees including: diameter at root collar, height, number of stems and crown width were measured, then trees were finally cut down. Trunk and branches were separated and weighed. Some disks were taken and moved to the laboratory to determine the dry/fresh weight ratio and wood specific gravity and subsequently to calculate the dry weight of trunk, branch as well as aboveground biomass. Linear regression analysis was conducted to create allometric equations. Results showed that there was a strong and significant correlation between volume/biomass of Acer monspessulanum and quantitative characteristics of standing trees. The most robust predictors of volume and aboveground biomass were found to be crown width and crown area (R2 = 0.83) followed by equivalent diameter at root collar (R2 = 0.81). The normalized root-mean-square error amounts were found to be under 20% for most models especially for predicting biomass of branches. Tree height combined with equivalent diameter at root collar (EDRC) explained 87% of the variations in volume and biomass, creating precise models. It is concluded that crown diameter and EDRC can predict biomass and the volume of A. monspessulanum as a multi-stemmed tree with high accuracy and precision.

Melissa officinalis is a perennial herbaceous plant from Lamiaceae family, widely used in food and pharmaceutical industries to add aroma. Drought stress in plants may happen due to the increase in water loss, insufficient water absorption or both. Salicylic acid (SA) is an important secondary metabolite in plants with hormone-like action in some biochemical pathways. Adding it during water-deficit stress, may alter a number of physiological processes, increasing the resistance of plant against possible damage by water loss. The aim of this study was to examine the effect of drought stress (DRU) on secondary metabolites of Melissa officinalis and also the efficacy of salicylic acid treatment to minimize the damages. According to the results, treatment of plant with 0.7 mM salicylic acid had considerable alteration in the quantity of important secondary metabolites. Protein concentration increased in all stages; Chlorophyll a reached to the highest amount; the amount of the MDA increased at the first and second stages in 1/3 fc drought treatment as well as at the third stage in 2/3 fc. Besides, total phenol content increased at stage I in 1/3 fc drought and the flavonoid content increased in 1/3 fc drought at all stages. Finally, content of anthocyanin was increased at first and third stages 1/3 fc drought, as well as at second stage in 1/3 fc drought. In conclusion, application of salicylic acid (0.7 mM) was useful for improving quality of lemon balm subjected to stress due to water deficit.

This study provides fundamental information on some key aspects of the reproductive traits of qanati tailor fish, Alburnoides qanati, an Iranian endemic, poorly studied cyprinid fish species. Sampling was performed on a monthly basis during one year (from March 2011 through February 2012) from a tributary of endorheic Kor River Basin, Southern Iran. The results of data analyzing showed that the sex ratio in the population of qanati tailor fish is 1:1 except for those in January and April. Based on the size, shape and weight of the gonads, degree of occupation of the body cavity, presence or absence of ripe oocytes, diameter of the oocytes in the ovary, and histological observations, five typical gonad maturation stages were described for females using macroscopic and microscopic criteria. Based on the percentage of the late gonad maturation stage (V) and high frequency of large oocytes it was concluded that A. qanati spawns during spring with its peak in April. These results were in accordance with those of three reproductive indices (gonado-somatic, modified gonado-somatic and dobriyal). Absolute fecundity was obtained between 732 and 2368. Study on its eggs by scanning electron microscopy (SEM) revealed that the fish have adhesive eggs, which could explain its low fecundity compared to other cyprinids.

One of the most important anthropogenic pollution types in countries with oil production is soil and water contamination by petroleum. Phytoremediation is an emerging green technology for cleaning up polluted soil. A greenhouse experiment was conducted to study the effect of oil-contaminated soil on Echinacea purpurea with four concentrations of crude oil - contaminated soil: control = 0, 0.5% = 5000, 1% = 10000, and 2% = 20000 mg kg-1. Morphological and physiological traits were evaluated after 90 days. Gas chromatography determined the removal rate percentage of total petroleum hydrocarbons (TPHs) in the soil. The results show that this plant has potential for removing TPHs, up to 45.5% at 1% crude oil contamination, while the removal rate by natural attenuation is only 32%. Data from morphological and flowering indices including shoot and root fresh weights, shoot and root dry weights, flower stem length, flower longevity, flower anthocyanin, and visual stress symptoms show significant differences within treatments. Based on the results, E. purpurea can tolerate crude oil concentrations in soil equal to or greater than 5000 and 10000 mg kg-1 (0.5% and 1% w/w). However, flowering was not observed at treatments of 1% and 2% crude oil contamination. As crude oil concentration increased, physiological parameters such as total chlorophyll, protein, and antioxidant capacity significantly decreased, while other parameters including leaf anthocyanin, electrolyte leakage, malondialdehyde, proline, and total carbohydrate all increased. Overall, E. purpurea is a widely - spread species that can be effectively used for phytoremediation of ≤10000 mg kg-1 crude oil contaminated soil.

Water shortage is one of the most important environmental stresses in Mediterranean regions. Poor seedling quality may account for the failure of oak regeneration. To determine the best seed origin of Quercus brantii, we investigated on seedlings collected from 20 mother trees in the Zagros Mountain forests 700 to 2200 m altitudes above sea level. Seedlings from different altitudes were irrigated at 25%, 50%, 75% and 100% of field capacity (FC), from June through the end of August 2005, and then their growth, physiological and biochemical parameters were examined. The results showed that the activity of peroxidase (PO), superoxide dismutase (SOD), and amylase, as well as the rate of membrane lipid peroxidation and the content of lignin were not affected by water deficit stress. However, the survival and growth rates were reduced below 50% FC. Seedlings originated from lower altitudes had higher growth and survival rate than those from higher altitudes below 50% of FC. The seedlings grown under 50% FC had also high phosphorus and water soluble carbohydrate contents. In conclusion, the present study showed that the seedlings from lower altitudes, which their mother trees grown under warmer climate condition in growth season, were more resistant to water deficit due to higher root to shoot ratio, phosphorus and water soluble carbohydrate contents under water deficits.

Marine microorganisms have unique physiological properties and novel metabolites such as biosurfactant to live in extreme habitats (e.g. oil polluted environment). The aim of this study was to characterize some biosurfactant-producing bacteria collected from sediment and seawater samples from the Caspian Sea. These bacteria were isolated using enrichment method in ONR7a medium with crude oil as sole carbon source. Five screening tests were used for selection of the bacteria including hemolysis in blood agar, oil spreading, drop collapse, emulsification activity and bacterial adhesion to hydrocarbon test (BATH). The bacteria isolated were identified using molecular methods. Eighteen biosurfactant-producing bacteria (from 44 different colonies isolated) were selected and 9 isolates were screened as predominant biosurfactant producer belonging to Pseudomonas stutzeri (Strain S1-4-2), P. balearica (Strain S1-4-1), Pseudomonas sp. (Strain S2-1), P. stutzeri (Strain R3-2), P. chloritidismutans (Strain K4-1), Achromobacter xylosoxidans (Strain K4-3), Acinetobacter radioresistens (Strain S1-2), Acinetobacter calcoaceticus (Strain K4-2) and Citrobacter freundii (Strain R3-1). The largest clear zone diameters for oil spreading method observed for P. balearica strain S1-4-1 (14 mm). Also, this strain has the best emulsification activity (100 %); surface hydrophobicity (BATH: 77 %) and reduction of surface tension (34.5 mN m-1). Thus, this strain selected as the best isolated strains. The results of this study confirmed that there is sufficient diversity of biosurfactant-producing bacteria in the Caspian Sea and the environmental problem can be resolved by application of these bacteria in petrochemical waste water.

The purpose of this study was to determine and compare the concentrations of six toxic metals (Cd, Pb, Fe, Cu, Zn, Mn) in the muscle and hepatic tissues of five commercially important fish species including narrow-barred Spanish mackerel, Scomberomorus commerson, Black pomfret, Parastromateus niger, Silver pomfret, Pampus argenteus, blackspot snapper, Lutjanus fulviflammus and Tigertooth croaker, Otolithes ruber, since they are very common in the household fish consumption. The fish samples were collected from three main landing areas along Bushehr and Hormozgan provinces during spring 2017. Our results indicated that lead concentration was higher than those of other measured heavy metals in all examined fish species, while it was an inverse situation for cadmium. We found that the concentration of the measured metals totally were higher in the liver than in muscle of all the examined fish. There was no significant intra-specific variation in metal concentration among the fish from the same species. Since it is very important to the consumer to choose between the species, we also detected the mean values of the metal concentration in the muscle of the relatively same aged species, sampled from same stations.