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Measurement of chlorophyll-a can be considered important to investigate the primary production of an ecosystem. This study aimed to investigate chlorophyll-a concentration, primary production and the factors affecting them in Shadegan Wetland located in Khouzestan Province - Iran. Sampling for measuring (NO₃, PO₄, BOD₅, DO, pH, EC, salinity, temperature) was performed seasonally at five sampling stations of the wetland (Canal, Ragbeh, Khoroosi, Mahshahr and Atish), from March 2013 – through February 2014. Results showed that chlorophyll-a concentrations in Canal station were significantly higher than that in the other stations; however, there were no significant differences among the other sampling stations (p>0.05). The maximum and minimum primary production (and chlorophyll-a) (62, 1.14 mg/m³) were observed at Canal and Ragbeh stations, respectively. Annual average chlorophyll-a concentration was 10.28 mg/m³, and there was no significant seasonal difference (p>0.05). The maximum value of chlorophyll-a was observed in the fall (29.63 mg/m³), whereas, the minimum value was related to the spring (4.07 mg/m³). Among the water physicochemical parameters, nitrate had a significant effect on chlorophyll-a concentrations. According to trophic state index (TSI), Shadegan Wetland is mesotrophic in the spring and winter, whereas it is eutrophic in the summer and fall. Overall, the lake is suitable for warm water species. 

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Seasonal samplings were conducted over a year to study population dynamic of Carasobarbus luteus in Shadegan Wetland. Samples were collected from five sampling stations in Shadegan Wetland (Salmane, Rogabe, Khoroosi, Mahshahr and Atish) from April 2014 to March 2015. From total number of 1608 samples, 276 individuals were male and 1332 individuals were female. Length-weight relationship was W=0.013L^3.0124 (R²=0.92) for males; and W=0.0136L^3.0117 (R²=0.91) for females, showing an isometric growth pattern. Condition factor (K) was calculated to be 1.308±0.15 and 1.368±0.17 for the males and females, respectively, showing significant difference between the genders (p<0.05). Also, the results show that this species spawns in April-July with a long spawning period and sexual dormant period in autumn to early winter. Mean length at maturation was 161 and 174 mm for males and females specimens; whereas, weight of matured fish was 60 and 80 g for the males and females, respectively. Growth indices including L_∞, growth coefficient and t₀ were 305 and 301 mm, 0.67 and 0.55 per year and 0.23 and 0.29 for the males and females, respectively. Natural mortality, fishing mortality, total mortality, Munro Ф' and coefficient of exploitation were 1.22 and 1.02 per year, 1.61 and 1.45 per year, 2.83 and 2.47 per year, 2.79 and 2.72, and 0.57 and.59, respectively for the males and females.