Ecological study in ponds of Litopenaeus vannamei

This study has carried out on five earth ponds of Litopenaeus vannamei shrimps investigation and Mahan Siraf farm s which located at Helleh site in the Bushehr province from may 2007. main objectives’ were: (1) Measurements of quality factors in water and sediment, Planktons and benthoses, (2) quality factors’ effects on growth and survival of Litopenaeus vannamei. With respect the time of shrimp stocking and harvesting, the frequencies of water and sediment sampling were done per 10 day and once per month, respectively. both sediment sampling of the pond beds have done before and after harvesting. The measured factors in the water ponds were: pH, salinity, dissolved oxygen, transparency, temperature (Twice a day in the morning and the afternoon), chlorophyll-a, nitrate, nitrite, orthophosphate, iron, biochemical oxygen demand, TSS, TDS, Planktons. The parameters (pH, total organic matter, iron) were measured in sediment. The measurement of grain size has done in two times (before and after harvesting). Independent variables including nitrate, Ammonia, orthophosphate, iron and chlorophyll-a had significant correlations with shrimp weights as dependent variable. Nitrate showed the highest correlation with the shrimp weights (r=0.921). overall correlation of fifth most important factors with the shrimp weights, namely nitrate, orthophosphate, Ammonia, iron and chlorophyll-a was estimated to r=0.999. The results show low concentration of the essential nutrient such as phosphate and nitrate, high concentration of ammonia, undesirable’s transparency, and a great amount of clay in pond beds. On the basis of above description, required to renewing management in fertilizing, feedings, liming qualities of the bed

A survey on effects of shrimp aquaculture on the coastal waters of Bushehr (Helleh and Mond)

The effects of aquaculture industry on the environment were evaluated by studying the water quality of Bushehr costal water during culture season 2005 and 2006. The variations of selected parameters such as total phosphorus, ammonia, chlorophyll a, pH, salinity and... Were monitored in effluent canal, influent canal and open sea in Helleh and Mond regions as monthly. Following occurrence of White Spot Disease (W.S.D) in the shrimp ponds of Bushehr province, shrimp culture suspended and entrance of effluent waters completely were blocked since August 2005, despite the absence of aquaculture sewage evaluation of environment and sampling were continued. During releasing of sewage of shrimp ponds to the coastal waters of Bushehr in Jun 2005, the average amount of ammonia in Helleh and Mond were obtained to be 0.161 mg/l and 0.194 mg/l, however the average amount of total phosphorus in Helleh and Mond regions were 0.149 mg/l and 0.043 mg/l, respectively. Although effluent water suspension, amount of ammonia and total phosphorus were increased in both region especially in June 2006. Comparing present data in Jun 2005 and recorded data from culture period 1997-2003 with permitable range of municipal and aquaculture waste show that; aquaculture industry on both regions have not had any obvious negative effect on the coastal waters of Bushehr but it seems if other sources of pollutions in the region is not controlled, then the aquaculture industry can contribute to occurrence of environmental problems

Hydrology and hydrobiological study of the Persian Gulf in the Bushehr region

In order to investigate some ecological condition of the waters of Bushehr province in the Persian gulf between 50~'-01 E to 52~'-47 E and 26~'-39 N to 29~'-03 N, 18 major and 16 minor stations have been studied from Nayband bay to Kharg Island, using R.V. Ferdows 1. There have been a preliminary survey in winter 2001, 4 seasonal surveys in 2001-2 and a complementary one in summer 2002. During this period the seasonal environmental conditions, physico-chemical parameters, zoo and phytoplankton concentrations in water layers, macrobenthoses and sediments were studied. Sea bed swelling in the Motaf region has resulted in division of the area in two parts and in a such away that the climatic and chemico-physical conditions in the southeast area are different from the northwest area. In the southeast area the termocline, halocline, picnocline and oxycline are generated in spring, increased in summer, moved down to the deeper layers in fall and disappeared in the winter. In the Northwest area the clines are only formed in spring and summer but disappear in fall and winter due to almost perfect water column mixing resulted from climatological conditions. During survey period the water temperature ranged from 18 34.1~'C, salinity 37.9 41.3 ppt, conductivity 51.3 70.4 ms/cm, sigmaT 23.1 30.2 g/cm3, dissolved oxygen 0.2 8 ppm, and chlorophyll a 0.1 3.6 mg/m3. It is observed that salinity, conductivity and sigmaT have increased from surface to depeer layer, while oxygen and chlorophyll a had a pick in mean layers but temperature have decreased from surface to the depth. Temperature and conductivity decreased from southeast to the northwest and from costal to offshore. Salinity and sigmaT increased from southeast to the northwest. Dissolved oxygen and chlorophyll-a did not show any trend. The concentration of nutrients including ortho silicate (Si-SiO4- 4), ortho phosphosphate (P PO4-4), nitrate (N NO3- ) and nitrite (N NO2- ) varied between 0.4 13.3, 0.05 1.6, 0.1 12.3 and 0.1 1.4 ~kmol/l, respectively. The overall nutrient concentrations increased from surface to depth. 61 genuses of 5 phytoplankton groups and 8 branches, 12 classes of zooplankton were identified. The identified phytoplanktons included 42 Diatom, 16 Dinophyceae, 3 Cyanophyceae, one Chrysophyceae and one Euglenaphyceae geneses. The highest intensity of phytoplanktons was recorded in summer, while in the case of zooplankton, was recorded in spring. Diatoms had the highest variety in all seasons and the maximum abundance in fall and winter. Cyanophyceaes were predominant group in the spring and summer. On the contrary to zooplanktons, the intensity of phytoplanktons decreased from coastal to the offshore waters. The highest intensity of all planktons (zoo and phyto) was in 10-20 m layer. The intensity of phyto plankton increased from southeast towards northwest. The zooplankton concentration didn t follow any particular trend. The identified macrobenthoses were 69 families including 34 polychaets, 22 gastropods, 10 of bivalvs, 1 crustacean, 1 scaphopoda, 1 foraminifera, 5 classes and 6 orders of crustacea, 1 order of echinodermata, 1 fish larva and 6 branches of other benthoses. Intensity and biomass of all groups were determined. The polychaets and malacostraca had the most abundance in contrast to the other groups. Macrobenthosis intensity decreased from coast to the offshore in southeast of Motaf region, while the middle stations of northwest of Motaf had a better intensity. The mean abundance and biomass of total area decreased from coast to the offshore, and the slope of decrease in biomass was more than abundance. Seasonal minimum and maximum abundance ranged from 1457 to 1903 per square meter in spring and winter, and the biomass ranged between 7.8-10.8 g/m2 in summer and spring, respectively. In spite of high abundance of macrobenthose in the transect no: 13, the estimated biomass was lower than other transects. This might be due to prolonged exposition to more pollutant. The grain size of sediments was classified as gravel, sand, silt and clay. The organic matter of sediments ranged from 1.12 3.3% with annual average of 1.6%. The grain size of sediments in southeastern point was coarser than other areas. The middle stations of northwestern area had fine grain and more organic matter in contrast to the offshore and coastal stations

Environmental impact assessment (EIA) on cultivation of the nile tilapia (Oreochromis niloticus) with brackish water in Dashtestan

EIA is a worthy tool for identifying and assessing potential impacts and control them.it compatibles environmental aspects with sustainable development. In order to predict the effects of tilapia culture activities on regional we gathered physical, biological, and social information to quantify the activities effects on them. We addressed 42 impacts consist of 31 positive, and 11 negative. These affect half of social, 33% of physical, and 17 of biological elements. This equivalent with -42, +304, and+36 when puts in the charts.in order to have a good and comprehensive assessment of activities Leopold matrices was employed. Based on summarized values from this we have +380and -82 results +298. This means that this activity has a great positive result especially on socio-economic environment. These kinds of studies are highly recommended for other parts of the Bushehr province e.g Dashtestan county that most of their water resources are brackish and not suitable for agriculture

Impact assessment of master plan of "attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products" on Bushehr city environment: A case study, Shoghab research station

This study is a part of the national and technology master plan entitled "Attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products". The goals of this work were to assess the environmental effects of Specific Pathogen Free shrimp production complex on surrounded region in Persian Gulf (Shoghab) research station in Bushehr city. The environmental impacts were assessed in Persian Gulf (Shoghab) research station in Bushehr city by usage of simple checklist for impacts prediction, and scaling check list for assessment during Feb 2012 till Sep 2014. Flushing the effluents to the sea is the biggest concern of this project that can resulted in health impacts on aquatic and human communities that can be avoided by treatment. Low diversity in activities beside lack of environmental sensitive elements in the region leads us to use of scaling check list for impact assessment. Environmental grade of each activity can be achieved by stratification of them according to their intensity, significance and scale. We reached +320 and -198 for positive and negative points respectively that sounds a clear yes for execution choice

Impact assessment of master plan of "attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products" on Bushehr city environment: A case study, Shoghab research station

This study is a part of the national and technology master plan entitled "Attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products". The goals of this work were to assess the environmental effects of Specific Pathogen Free shrimp production complex on surrounded region in Persian Gulf (Shoghab) research station in Bushehr city. The environmental impacts were assessed in Bandragah research station in Bushehr city by usage of comprehensive method for impacts prediction, and Pastakia Matrix for assessment during Feb 2012 till Sep 2014. Results showed 8 negative and 3 positive environmental factors that affect by operating phase including 48% very slightly negative and 44.5% slightly positive and 7.5% very slightly positive effects. Although there is no significant different between negative and positive effects but based on national strategy on getting the technology doing such a projects is highly recommended. By the usage of technical methods in effluents treatment control and reduction of bad impacts is achievable

Environmental risk assessment of the activity of specific pathogen free shrimp production centers

This study is a part of the national and technology master plan entitled "Attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products". The goals of this work were to assess and analysis the risk factors of production of specific pathogen free Litopenaeus vannamei shrimp in its all stages (broodstocking, laravl production, shrimp farming, feeding and water quality), determining the pattern of outcomes monitoring, management and control of outcomes from April 2012 to September 2015 in Bandargah research station and Persian Gulf SPF Shrimp research station and their environment, belonging to Shrimp Research Center, located in Bushehr. Identification and screening of risk factors have been done based on Environment Aspect and Effect Analysis method, (EA)2, using a fine statement questionnaire and quantification of risks. The number of identified risk factors in Bandargah research station was 15 while it was 13 in Persian Gulf SPF Shrimp research station. The more number of risk factors in Bandargah station in respect to its number in Persian Gulf station is might due to lower level of biosecurity, physical structure and aging of Bandargah station and existence of two possible source of contamination, the Bushehr nuclear power plant pollutants and Bandargah fishing harbor, near to the station. On the basis of results, the maximum values of APN in Bandargah station was 42 while it was 30 in Persian Gulf station. These results revealed that the level of risk in Bandargah station is lower than that in Persian Gulf station. The most probable risks in both studied research stations are related to transmission of pathogens in shrimp feeding and water intake pollution