6 research outputs found

    AN ECOLOGICAL INVESTIGATION ON COLONIZATION OF FRESH WATER ARTIFICIAL REEFS

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    1 Colonization of four different artificial reefs (cemented rope, brick, wood and ceramic

    Effects of trout farm activities on water quality of Taleghan dam and related rivers

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    The result of chemical examination on samples demonstrates that most of assessed parameters met the environmental standards. The trend of BOD5 changes showed a decrease due to recreation of the rivers in the both studied points (1-4 stations of Khochireh zone and 5-8 Hassanjun zone). Therefore, aquaculture activities did not play a significant role in enhancing the instant organic load (p<0.05). Investigating the amount of total phosphorous revealed that Khochireh zone owned less pollutant consists of phosphorous compounds in comparison to Hassanjun zone. Hilsenhoff was an applied to determining the amount of pollution of assessed rivers. Biological and chemical examination of the Hassanjun, Khochireh and the main branch of Shahrud River was organized and done in May, 2012 by fast sampling method. Also monitored levels of total phosphorous showed the both rivers experienced an increase in downstream compared to upstream. The trace of frequency variation of macro benthos showed that Chironomidae and Elmidae families which are from Diptera and Coeloptera orders considered as the most crowded populations of macro benthos in the study zone with the total frequency average of 11.6 and 10.0 per square meter. The result of studying on macro benthos based on Hilsenhoff biological index elaborated in Khochireh zone the activity of aquaculture industry (without any urban zone and other industries) led to deteriorate the water quality from average in station 1 to average –weak in station 2 whereas, fish farms couldn’t affect the quality of main branch of Shahroud river due to higher volume, so didn’t any significant change in third and fourth station. In the Hassanjun River at the upstream of the fish farm the water quality seems to be never appropriate, that be alleviated to average in downstream. The main branch of Shahroud River was affected due to admixture with hassanjun River; therefore turned the quality from very good in station 7 to bad in station 8, obviously due to the low quality of Hassanjun River. To conclude, the chemical and biological investigation illustrate aquaculture activity throughout the Shahroud River affects the water quality in an ignorant level which is offset by recreation ability of the river. However, other types of pollutants which are emitted by other industries decrease the water quality of studied zone particularly at the downstream and entrance of the Taleghan dam

    Optimum management of warmwater fish farms stocking, capacity determination, growth rate and brood stock managements and harvesting

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    This study was conducted to codify the guideline and indexes of optimal management in warm-water fish farms to attain sustainable aquaculture which they are population density, species diversity, brood stock'smanagements, capacity determination, growth and harvesting managements in cultural ponds. As results, these guideline and indexes were codifies for these fish farms and propagation centers. It's obviously that these sustainable patterns can be used for improving of permanent development for this aquacultural industry

    A study on water quality and physio- chemicals parameters in surface water, underground water and wastewater of Mangol dam basin (Mazandaran province)

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    This study was conducted to determine water quality of surface water (7 stations), ground water (5 stations) and wastewater (4 stations) at Haraz River during instruction of Mangol Dam in 2009-2010. This study is to follow physico-chemical fluctuation of waters and compared the data obtained with previous studies and standard levels. Results of current study showed that annual mean with standard error of temperature, DO, BOD_5, COD, HCO^3-, CO_3^2-, TA, Ca^2+, Mg^2+, TH, TSS, TDS, Cl^-, PO_4^3-, NH^4+, NO2- and NO3- were observed 12.7 (±0.61) centigrade, 10.13 (±0.12), 2.1 (±0.1), 7.71 (±0.99), 28.1 (±6.1), 14.34 (±1.64), 36.30 (±2.33), 64.66 (±2.34), 28.84 (±1.52), 271.62 (±8.41), 0.37 (±0.03), 0.30 (±0.02), 28.02 (±1.96), 0.06 (±0.01), 0.010 (±0.001) and 0.94 (±0.03) mg/l, pH was 8.00 (±0.02) and EC 0.50 (±0.02) ms/cm in surface water. The annual mean with standard error of temperature, HCO^3-, CO_3^2-, TA, Ca^2+, Mg^2+, TH, TSS, TDS, Cl^-, PO4^3-, NH^4+, NO^2- and NO^3- were observed 21.62 (±1.03) centigrade, 54 (±5), 11 (±5), 57 (±5), 208.6 (±42.5), 109 (±23), 1088 (±165), 0.065 (±0.017), 0.97 (±0.11), 317.8 (±76.2), 0.25 (±0.06), 0.06 (±0.01), 0.0007 (±0.0001) and 0.78 (±0.05) mg/l, pH was 7.37 (±0.07) and EC 1.98 (±0.23) ms/cm in underground water. In addition, the annual mean with standard error of temperatute, DO, BOD5, COD, TSS, TDS, and NO3- were observed 12.7 (±0.61) centigrade, 13.59 (±0.87), 9.80 (±0.12), 2.22 (±0.18), 7.54 (±1.02), 0.50 (±0.03), 0.320 (±0.008) and 0.990 (±0.016) mg/l, pH was 7.95 (±0.02) and EC 0.64 (±0.01) ms/cm in wastewater. Quality of surface water of Haraz River and its branches were almost contained suitable for usual applications, but sometimes the quality of surface water based on BOD5 need to more attention for man uses (such as supply of drinking water). In addition, the quality of surface water was relatively suitable for aquatic based on the aquatic standard levels. Results also showed that water quality index (WQI) was declined from upstream to downstream and some parameters were not in standard ranges. The quality of surface water classified in group II at all stations based on water classification rules which it shows serious water quality changes due to environmental destroyed and domestic, agriculture sewage pollutions. Groundwater were affected by different springs at middle and downstream which they caused change physico-chemical characteristics and water quality. Wastewater was classified from good to moderate based on BOD5. The quality of wastewater was declined at downstream with decreasing DO and pH and increasing BOD5 and pollutants

    A comparison among benthic macrofauna in three environments around Vales Point Power Station, Lake Macquarie

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    Temporal variability in macroinvertebrates diversity patterns and their relation with environmental factors

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    Abstract. Gerami MH, Patimar R, Negarestan H, Jafarian H, Mortazavi MS. 2015. Temporal variability in macroinvertebrates diversity patterns and their relation with environmental factors. Biodiversitas 17: 36-43. Seasonal changes are the most important factor in temporal variability of macroinvertebrates communities in marine benthic zone. Realizing the pattern of these changes are the key attributes to maintain benthic resources. For this purpose this study aimed to investigate temporal variability of macroinvertebrates diversity patterns in different seasons in Hormozgan province waters, Persian Gulf. Five sites were identified and sampling was carried out randomly at three places with three replicate in each site from autumn 2014 to spring 2015. Physiochemical properties of water were recorded in each sampling site. Total of 19 macroinvertebrate orders were identified form four seasons in all sites. Results showed that Polychaeta were dominant taxa in all seasons and maximum diversity of benthic macroinvertebrates exhibited in winter. According to evenness index (E1), abundances of species were most balanced in spring. Analysis of weight and density revealed that the species diversity and mean weight of macroinvertebrates had maximum in winter and minimum in summer. Macroinvertebrate community structure was similar in the spring and summer and partly discriminated from remaining two seasons. SIMPER analysis confirmed these dissimilarities and revealed that Foraminifera, Gastropoda and Polychaeta have three major contributions in dissimilarities between seasons. According to BIO-ENV analysis, oxygen and chlorophyll a were the best variables (r = 0.7143) explaining changes in the abundance over time of the benthic fauna under study. On the contrary, eight orders (Amphipoda, Secernentea, Cumacea, Euphausiacea, Gastropoda, Isopoda, Anthozoa and Sagittoidea) did not show any convergence with environmental factors in this study
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