Contamination of heavy metals represents one of the most pressing threats to water and soil resources, as well as human health. Phytoremediation can be potentially used to remediate metal contaminated sites. In this study, concentrations of copper, zinc, iron, and magnesium accumulated by native plant species were determined in field conditions of Hame Kasi iron and copper mine in the central part of Iran in Hamadan province. The results showed that metal accumulation by plants differed among species and tissue bodies. Species grown in substrata with elevated metals contained significantly higher metals in plants. Metals accumulated by plants were mostly distributed in root tissues, suggesting that an exclusion strategy for metal tolerance exists widely amongst them. The mentioned species could accumulate relatively higher metal concentrations far above the toxic concentration in the plant shoots. With high translocation factor, metal concentration ratio of plant shoots to roots indicates internal detoxification metal tolerance mechanism; thus, they have potential for phytoextraction. The factors affecting metal accumulation by plant species including metal concentrations, pH, electrical conductivity, and nutrient status in substrata were measured. Mostly, concentrations of zinc and copper in both aboveground and underground tissues of the plants were significantly, positively related to their total in substrata, while iron, zinc, and copper were negatively correlated to soil phosphorus.

Sperm motility is a prerequisite factor determining semen quality and fertilizing capacity. The effects of environmental factors including pH, cations and osmolality as well as the role of dilution rate on sperm motility parameters in Acipenser persicus were studied. The best pH and dilution rate for activation of spermatozoa were pH 8.0 and dilution ratio 1:50. Ionic factors can stimulate the initiation of sperm activation. The maximum percentage of motile sperm and total duration of sperm motility were observed in solutions containing 25 mM NaCl, 0.2 mM KCl, 3 mM CaSO 4 , 10 mM MgSO 4 and sucrose with an osmolality of 50 mosmol kg 21. The present study provides us with some basic knowledge about sturgeon spermatozoa biosensitivity to ionic and osmolality effects. A sensitivity of A. persicus sperm was observed after induction of activation of sperm motility in solution containing cations or sucrose with high osmolality. Concentrations more than 50 mM Na 1 , more than 1 mM K 1 , more than 3 mM Ca 21 and more than 10 mM Mg 21 had negative effects on sperm motility. Also, osmolality more than 100 mosmol kg 21 had an inhibitory effect. It is clear that ions and osmolality stimulate the motility of spermatozoa by changes in the properties of the plasma membrane including its potential and its ionic conductance. The inhibitory role of high osmolality of the swimming medium (more than 100 mosmol kg 21 ) and insufficient osmolality of the seminal plasma to inhibit semen motility suggested that osmolality is not the principal factor preventing sperm motility in seminal fluid but that K 1 is a major inhibitory factor of sperm motility in seminal plasma.

As the largest extant cat species in west Asia, the leopard (Panthera pardus) shows high morphological variation, which has led to the description of seven different subspecies in the region. Different investigations have tried to clarify its phylogenetic structure; however, sample size and spatial distribution insufficiently represent the Iranian population, the largest remaining bulk of the Persian leopard (P. p. saxicolor) in the Middle East that probably functioned as a source for the subspecies' range. We examined sequence variation in the mitochondrial NADH-5 gene for 25 leopards from different parts of Iran. Also, we examined 49 adult male skulls to understand the morphological variation of the Iranian leopard population. Our craniometrical results revealed that while no differentiation is seen based on size or shape characteristics from different parts of Iran, larger individuals normally belong to the northern range. Time-calibrated Bayesian phylogenetic analysis suggested that the Iranian female lineage is a monophyletic group that diverged from a group of Asian leopards in the second half of the Pleistocene. Three closely related haplotypes were identified for the entire country: one commonly found haplotype throughout Iran, south Caucasus and Turkmenistan and two localized haplotypes were sequenced from southern Zagros and eastern Alborz. Accordingly, the Persian leopard population in Iran as well as in neighbouring countries can be protected as a large management unit through large-scale conservation planning. Moreover, the available captive stock of the Persian leopard represents an invaluable source for reintroduction for countries interested in restoring their locally extinct population.

Sperm density, mineral and organic composition of the seminal plasma and their physiological relationship were investigated in the Caspian brown trout (Salmo trutta caspius). To establish a rapid and accurate method for assessment of sperm density, three di¡erent techniques were used: sperm counting, spectrophotometry (at 480 nm) and determination of the spermatocrit. The seminal plasma contained 159.26 AE 8.84 mM sodium (Na), 33.72 AE 2.01mM potassium (K), 133.04 AE 5.96 mM chlorine (Cl), 1.68 AE 0.2 mM calcium (Ca) and 0.988 AE 0.13 mM magnesium (Mg). The following organic components were found: total protein 0.75 AE 0.14 mg100 mL À 1 , cholesterol 2.86 AE 0.58 mg L À 1 and glucose 3.81 AE 1.04 mM L À 1 . The mean sperm density was estimated to be 3.3 Â 10 9 spermatozoa mL À 1 . The spermatocrit (%) ranged from 25 to 52 in sperm samples. Highly signi¢cant linear relationships were found between sperm density and spermatocrit (R 2 5 0.703, Po0.001) and sperm density and optical density (R 2 50.909, Po0.001), indicating that optical density can be used as a quick and accurate method of estimating sperm density. Signi¢cant relationships were also found between sperm density and Ca, Mg and total protein of seminal plasma. A signi¢cant correlation was also observed between the Ca and Mg concentrations (R 2 50.774, Po0.01). The following correlations were observed between mineral and organic components: total protein and Ca (R 2 50.462, Po0.05), total protein and Mg (R 2 50.518, Po0.05) and glucose and Cl (R 2 50.374, Po0.05). These parameters should be considered when developing procedures for either arti¢cial fertilization or for cryopreservation of sperm. Sperm density and seminal plasma composition in Salmo trutta caspius A Hatef et al.

No abstract