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The present study was conducted in Chapkrud Joibar fish rearing farm and the effect of plankton and fertilizers transferring to the ponds and their effects on growth, survival of carps and plankton changes in pond were investigated. The ratios of C:N:P 88.6:7.5:1 adjusted for all treatments. The treatments consisted of 1- fertilization with 6000kg/ha per year, 2- fertilization with 12000kg/ha per year, 3- fertilization with 6000kg/ha/year and phytoplankton treatment and 4- fertilization with 12,000kg/ha per year and phytoplankton treatment. At the end of this experiment, treatment 4 provided the best growth conditions for rearing of carps. The highest initial production and number of phytoplankton per unit were observed in treatments 4 and 3, respectively, and had a significant difference with treatments 1 and 2 (P<0.05). The Ankyra, Chlorella, Scenedesmus, Tetrastrum, Spirogyra, Navicula and filamentous algae had the highest frequency of phytoplankton in ponds as primary productions. The main zooplanktons and benthos of the ponds were Rotifer, Daphnia, Copepoda, Seratopogonide and Vetivolid. Therefore, according to the research objectives, increasing the production per unit area and optimizing the amount of fertilization in pond. Treatment 4 including plankton, and fertilization with concentration of 12,000kg/year had the best results, which if it mixed with vermicompost fertilizer will improve the carps culture system.

Primary production is a key indicator in the evalution of aquatic ecosystems that can directly affect carbon sequestration. Due to climate change and environmental dynamics, this component has changed spatially and temporally in different ecosystems. Therefore, to understand and monitor these changes, the most important influential parameters include; sea surface temperature, chlorophyll-a and algal bloom on this component and their changes were analyzed based on the time series. Images related to Chl-a, SST and NPP from January 2003 to December 2018 were used by MODIS sensor and VGPM model to estimate NPP in the study area. Aftar pre-processing and extracting the time series algorithm, the trend of variation was determined using the mann-kendall and theil-sen procedure. Then, using enhancing false color composite, algal blooms in the Persian Gulf and the sea of Oman were identified and the amount of chl-a concentration in the algal bloom area and outside the area was determined.  The results of trend analysis with theil-sen procedure showed that the rate of change for chl-a is decreasing in all regions except the fifth region. The highest amount was observed in the fifth region (-0.19), which corresponded to the rate of NPP. The results also show that the highest amount of NPP in the first region in March and the lowest in June and July (540 and 690 gC/m2/day), which corresponds to the amount of chl-a concentration. Despite the apparent correlation, there is no cause-and-effect relationship between SST and chl-a as well as chl-a and NPP. In this way, factors other than chl-a can be considered for algal bloom and NPP.

A completely randomized experimental design in triplicates was conducted to evaluate the effects of different levels of nitrogen with the constant level of carbon and phosphorous on production of warm water fish in Chapakrod fish farm in Joybar. The treatments were use of three levels of C: N: P, respectively, 1: 5.5: 88.6 (T1) 1: 7.5: 88.6 (T2) and 1: 9.5: 6.88 (T3). The mixed chemical fertilizers and organic manures consisted of chicken, cattle feces, vermi-compost, phosphate and urea mixed together to get different levels of CNP. The effect of different concentrations of nitrogen on phytoplankton abundance and chlorophyll, were investigated as well. At the end of experiment, the highest number of phytoplankton, chlorophyll, relative growth indices were significantly different (P

This study provides information on the effect of three light intensities (37.5, 62.5 and lOO!lmol photons.m- 2 s-1) and photoperiods (light:dark) cycle 8:16, 12:12 and 16:8h on growth rate, duplication time and biomass production in microalga Chiarella vulgaris. Stock of C. vulgaris was separated from water samples taken at Anzali Wetland, purified and cultured in lOOOml Erlenmeyer at constant temperature 25±0.5°C, using Zehnder medium.Cell count was conducted daily and biomass was measured at the exponential growth phase in different treatments. Analysis of variance indicated significant difference (P<0.05) among light regimes. The maximum growth rate 1.13d-1 was observed at 10011mol photons.m- 2 s-1 and 16:8h light duration and also the minimum duplication time 0.61d- 1 occurred at this treatment. The maximum biomass 2.05gr 1 was recorded at 62.5!lmol photons.m -2 s-1 and 8:16h light period.