فهرست مطالب

  • Volume:9 Issue:1, 2011
  • تاریخ انتشار: 1390/02/25
  • تعداد عناوین: 11
|
  • Imanpour Naminj., Mohammadim., Heydaris., Monsef Rad, F Pages 1-8
    Levels of contaminants in fish are of particular interest because of the potential risk to humans consuming them. This paper examines the levels of cadmium, lead, zinc and copper in liver and muscle tissue of Esox lucius and in sediments from the Anzali international wetland in Iran. The wetland is a nursery and feeding habitat for fish species both from the lagoon and the Caspian Sea, which are consumed by the local inhabitants and others. Eleven main rivers discharge agricultural, industrial, urban and municipal wastes into this wetland. Twenty five Esox lucius specimens, with a mean weight of 804.6?121g and mean length of 430.7? 2mm were collected from the wetland by multimesh gill nets in September and December 2007.. The age was determined from scale samples according to the annual ring structure. Average concentrations of Cd, Cu, Pb and Zn accumulated in the mid-dorsal muscle tissue (filleted and skinned) of fish were 0.001, 0.21?0.02, 0.13?0.01 and 2.55?0.18? g.g-1, respectively. The concentrations of these metals in liver samples were Cd: 0.0014? Cu: 0.96? 0.61, Pb: 0.11? 0.04 and Zn: 2.46?1.5? g.g-1. Significant positive correlations were detected between Zn and Cu with body weight, while negative correlations were found between Pb and body weight. The concentrations of Zn, Cu and Cd were below the maximum allowable concentrations for fish proposed by WHO and MAFF (safe for human consumption) but concentration of Pb exceeded the standard levels.
  • Shirangi, S. A., Kalbassi, M. R., Dorafshan, S Pages 9-16
    The main objective of this study was to assess genetic comparison of two migratory forms of Caspian trout Salmo trutta caspius namely fall-run and spring-run. Owing to the lack of information on its genetic differences, 5 microsatellite loci were used for 58 sample analyses. Genomic DNA was extracted from caudal fin using Roche DNA extraction kit and each PCR reaction was performed in a 25 μl reaction volume. Results revealed that the most allelic frequencies were observed in fall-runs of Caspian trout. The average observed and expected heterozygosity in fall-runs and spring-runs were 0.7719, 0.6108 and 0.4435,0.5911, respectively. In both groups except Str543INRA in spring runs, all loci had deviation from Hardy- Weinberg equilibrium. Furthermore except Str543INRA in spring runs, expected heterozygosity in all loci was more than observed heterozygosity. In conclusion microsatellite loci polymorphism in this study reveals low genetic differentiation between fall-runs and spring-runs. In order to increase gene flow between Caspian trout populations of different rivers and to increase the production of these fishes, restoration of rivers habitats, as well as using more breeders originating from various rivers is highlyrecommended.
  • Khoshkholghm., Pourkazemim., Nazaris., Azizzadeh Pormehr, L Pages 17-25
    The Persian sturgeon, Acipenser persicus (Borodin, 1897), is an economically important species, which mainly inhabits the Caspian Sea. However, little is known about its population genetic structure. In this study, variation in nucleotide sequences of the mitochondrial DNA (mtDNA) control region of wild stock Persian sturgeon was determined to assess the genetic diversity among different natural populations of this species. The fish (n = 46) were collected from four sites (Astara, Sefidrood, Noshahr and Bandare-Turkaman) in the south Caspian Sea. As a result 6 haplotypes and 44 variable sites were found. The average haplotype diversity (h) and nucleotide diversity (π) were 0.640±0.028 and 0.0442±0.011, respectively. Analysis of molecular variance (AMOVA) demonstrated that most variations occurred within samples, and the difference between the populations from Astara and Noshahr or Bandare- Turkaman was not significant (p <0.001). Estimates of gene flow indicated reproductive isolation between theSefidrood River population and the other collections. The divergence might be related to geographical isolation. The results are consistent with the findings from PCR-RFLP analysis (PCR-RFLP) and suggest considerable genetic diversity of the population from Sefidrood River.
  • Khosravanizadeha., Pourkazemim., Nowruz Fashkhami, M.R Pages 27-36
    The chromosomal spread and karyotype of Bleak (Alburnus alburnus) from Anzali lagoon were identified using tissue squashing techniques with injection of 0.5ml/100g body weight of 0.01% Colchicines solution in fish fingerlings. Kidney and gill tissues were then extracted and chopped in KCl 0.045M for 20 min and fixed in Carnoy solution in 3 stages. The chromosomal spreads were stained in 20% Gimsa for 30 min. From 347 chromosomal spread counts, the results showed diploid chromosome number of this species2n=50. Karyotype composed of 7 metacentric, 13 submetacentric and 5 acrocentric or subtelocentric choromosome pairs, and the number of chromosome arms (NF) was determined as NF=90
  • Jafarim., Baghbani, Sh., Tavilia., Zare Chahouki, M. A., Malekiana., Asadi Pasoojanin., Kohandel, A Pages 37-46
    Some chemical characteristics of root, shoot and litter of index species such as Salsola rigida, Artemisia sieberi and Stipa barbata commonly used in rangeland development projects were evaluated and compared. Chemical properties of soil under and between the above mentioned species were also studied. For this purpose, vegetation types of Stipa barbata and Artemisia sieberi - Salsola rigida were selected in Zarand-e- Saveh rangelands. Totally, 30 individuals of each species within each type were randomly selected for shoot, root and litter sampling and chemical analyses. Also, values of N, P, K, C and C/N ratio were measured in different parts of the species. Results showed that the highest and lowest C/N ratios were related to Stipa barbata root and Artemisia sieberi shoots, respectively. N and P values of Stipa barbata litter were the lowest while Artemisia sieberi and Salsola rigida shoots had the highest values of P and N, respectively. Litter of Salsola rigida and shoot of Artemisia sieberi had the lowest and highest K, respectively. C/N ratio of A. sieberi soil was lower than rest of the species.
  • Kharah., Sattarim., Nezami, Sh., Mirhasheminasab, S. F., Mousavi, S. A., Ahmadnezhad, M Pages 47-53
    The Boojagh international wetland with a surface area of 80 hectares and 25 fish species is located in the southwest shores of the Caspian Sea (Guilan province, Iran), but there is no report about fish parasites in this wetland. In the present study, a total of 553 individuals of 8 fish species including Cyprinus carpio (n=71), Abramis bjoerkna (n=153), Carassius auratus gibelio (n=89), Esox lucius (n=39), Rutilus rutilus caspius (n=36), Rutilus frisii kutum (n=81), Scardinius erythrophthalmus (n=119) and Tinca tinca (n=4), were collected in October 2001 through November 2003. Eight parasite species were identified in the fishes consisting of 1 nematode: Raphidascaris acus (in E. lucius and S. erythrophthalmus); 1 cestode: Caryophyllaeus fimbriceps (in R. rutilus caspius and C. carpio); 2 digenean trematodes: Asymphylodora tincae (in T. tinca) and Diplostomumspathaceum (in all of the fish species except for T. tinca and S. erythrophthalmus); 2 monogenean trematodes: Tetraonchus monenteron (in E. lucius) and Dactylogyrus sp. (in C. carpio, A. bjoerkna and C. auratus gibelio); 1 crustacean: Lernaea cyprinacea (in A. bjoerkna, T. tinca and R. rutilus caspius) and 1 leech: Piscicola sp. (in R.rutilus caspius and C. carpio). The occurrence of R. acus in S. erythrophthalmus and also that of C. fimbriceps in R. rutilus caspius are reported for the first time as new host records.
  • Parhizkarp., Sagheb-Talebi, Kh., Matajia., Namiranian, M Pages 55-65
    We studied 11 gaps covered with beech saplings (< 1.30 m tall) in a reserve compartment (compartment 139, district one, Langa forest, watershed 36: Kazemrood) of the Caspian beech forest in N Iran. Two transects, each 2 m wide, were laid along the longest (N-S) and shortest (E-W) axis of each gap. Five micro sample plots, each 4 m2, were established: one at the center, and one at each corner. Qualitative and quantitativecharacteristics of saplings with a diameter at breast height less than 7.5 cm were examined in the micro sample plots. Analysis of variance (ANOVA) and Kruskal-Wallis test were performed using SPSS software for quantitative characteristics, and chi-square test for qualitative characteristics. Results indicated that medium-sized (200-500 m2) gaps promote the growth of oriental beech saplings of desirable silvicultural forms during decay and initial stages.
  • Rafieyano., Et, Al Pages 67-79
    This study is a contribution to assess the high resolution digital aerial imagery for semi-automatic analysis of tree species identification. To maximize the benefit of such data, the object-based classification was conducted in a mixed forest plantation. Two subsets of an UltraCam D image were geometrically corrected using aero-triangulation method. Some appropriate transformations were performed and utilized. Segmentation was conducted stepwise at two levels and a hierarchical image object network wasconstructed. The classification hierarchy was developed and Nearest Neighbor classifier, using integration of different features was performed. Training samples and ground truth map were prepared through fieldwork. Accuracy assessment of the resulting maps in comparison with reference data showed overall accuracies and Kappa Index of Agreement of 90.2%, 0.82 (Area1) and 69.8%, 0.49 (Area2), respectively.Transformed images were advantageous to improve the results. The lower accuracy in Area2 can be attributed to high diversity and heterogeneous mixture of species. More detailed and accurate mapping of tree species would be fulfilled applying precise 3D data. The accuracy of detailed vegetation classification with very high-resolution imagery is highly dependent on the segmentation quality, sample size, sampling quality, classification framework and ground vegetation distribution and mixture.
  • Cocosa., Cocoso., Sarbu, I Pages 81-95
    This paper seeks to emphasize the flow variability in the Calnistea catchment by analyzing the local physiographic factors. The research has shown that the amount of precipitation that falls to the ground is low, the rocks in the region are soft, but highly permeable, gradients are gentle in most of the territory and vegetal cover is sparse and therefore cannot hold important amounts of water. Under the circumstances, the flow is controlled especially by precipitation, gradient and rock permeability, which largely explainsthe rather low values of the drainage density, as well as the frequency with which the rivers dry up completely. The moisture deficit of the summer season is compensated to a certain extent by the existence of a chain of ponds along the main streams. The situation could further be improved if local authorities will find the necessary financial means in order to excavate artificial channels to bring water from the neighboring catchments. Although the flow values are generally low, under exceptional synoptic conditions the heavy rainfalls can lead to the formation of flash floods that can damage settlements,transportation routes and crops. Consequently, it is necessary to build protection levees in the lowlands and to regulate the stream flow.
  • Rahbarm., Et, Al Pages 97-103
    Caspian brown trout (Salmo trutta caspius) is one of the economically valuable species in the Caspian Sea. Artificial propagation and production of larvae are the main problems in the early culture of this species. The purpose of this paper is to study the effect of reproductive performance of female broods on opposition reproduction efficiency in Caspian brown trout in the breeding season of 2009. Three groups of female broods (4, 5 and 6 years old) were fertilized with 9 male fish individually. The results showed that,6 year old females have maximum body weight (2150.0 ± 86.6 g), total length (59±2 cm), eggs weight (255.0 ± 30.51 g), egg size (5.37 ± 0.058 mm) and absolute fecundity rate (3060 ± 366.15), while highest average number of ovules in each gram of body weight (16.33 ± 0.58) and relative fecundity (2.08 ± 0.12) belonged to 4 years old females. There were significant differences in mean fertilization rate and survival rate untilabsorption of yolk sack stage (p<0.05) among the treatments studied. The present study showed that the eggs produced from fertilization of 6 year old female eggs and male mixed milt showed maximum average fertilization percentage (97.5 %), survival rate until eyed stage (92%), hatching percentage (93%), and survival rate until absorption of yolk sack (94.5%).
  • Pananjay, G.B.G., Et, Al Pages 105-110
    Protected areas are major tourism assets for a nation, particularly for developing countries providing sustainable benefit to the local community while funding for the maintenance and rehabilitation of the protected areas themselves. Valley of flowers national park is naturally meant for the conservation and study of western Himalayan flora. It became National park in 1982 and after that livestock grazing ceased and restrictions were imposed on nearby villagers. The valley has an unusually rich flora of over 600 Himalayan species growing in an area of less than 2500 hectares with many rarities. Animals found are nationally rare or endangered. It is also a habitat of endangered Asiatic black beer, brown bear, Himalayan musk deer and snow leopard, blue sheep are rare. The common leopard is reported from lower parts of valley closer to the villages. Local people have also reported evidence of Himalayan brown bear. Other factors that are contributing to ecotourism are beautiful landscapes, peaks, lakes and tarns etc. Because of the heavy influx of tourists and improper management practices the problem of solid waste in increasing at an alarming rate. This paper is an overview of the present ecotourism resources of the area and their future prospects for sustainable ecotourism.