To provide basic information for studying balancing mechanism of nutrition environment in aquaculture ponds, sediment samples were collected periodically during the breeding process of tilapia in ponds. Then various t...To provide basic information for studying balancing mechanism of nutrition environment in aquaculture ponds, sediment samples were collected periodically during the breeding process of tilapia in ponds. Then various types of nutrient content of the samples were detected and the changing rule was summarized. The results showed that dry weight of the sediment and content of TP, TN and TOC generally presented a trend of first increasing and then decreasing. The main production period of each nutrient was from July to September and the production percentage was close to 80% of the total production. The content of NH4^＋-N increased gradually and reached a peak in early August, then maintained at the peak level. NO2^--N content of the sediment in each pond was basically the same in the earlier aquaculture stage and decreased in middle stage with a big difference, then rose again in the later stage.展开更多
There is need for alternate quick-search of pathogens’distribution in community water sources,instead of the cumbersome“Escherichia coli detection.”Physical and chemical(physico-chemical)parameters were evaluated a...There is need for alternate quick-search of pathogens’distribution in community water sources,instead of the cumbersome“Escherichia coli detection.”Physical and chemical(physico-chemical)parameters were evaluated as veritable indicators of faecal Escherichia coli contamination of surface waters,using Adada River in Nigeria as case-study.Thirty-two(32)physico-chemical parameters were analyzed in the river(at specified geographical coordinates)for their quality and quantity and connected(using Pearson’s Correlation Analysis)with the distribution of the river’s isolated Escherichia coli.The 32 physico-chemical parameters consist of 11 cations,6 anions,7 physical properties,3 properties relating to oxygen and 5 properties relating to anions/cations.Physico-chemical indices from the analysis,revealed very significant positive correlation relationship of Escherichia coli with the presence of Mg(Magnesium)and K(Potassium)in the dry and rainy season,respectively.E.coli affinity tests(Kirby-Bauer Disc Diffusion)for these metals were also positive.Mg and K also showed significant positive Pearson’s possible paired correlation relationship.From this evaluation,potential index analysis indicated that Mg and K could serve as markers for the faecal bacteria indicators,and possible index for future monitoring of the potability of such surface water.The method is straight forward,cost effective,less cumbersome than other currently existing approaches.展开更多
基金Supported by Fundamental Research Funds in Central Public Welfare Research Institutes(2015JBFM28)National Agriculture Industrial Technology(CARS-49)~~
文摘To provide basic information for studying balancing mechanism of nutrition environment in aquaculture ponds, sediment samples were collected periodically during the breeding process of tilapia in ponds. Then various types of nutrient content of the samples were detected and the changing rule was summarized. The results showed that dry weight of the sediment and content of TP, TN and TOC generally presented a trend of first increasing and then decreasing. The main production period of each nutrient was from July to September and the production percentage was close to 80% of the total production. The content of NH4^＋-N increased gradually and reached a peak in early August, then maintained at the peak level. NO2^--N content of the sediment in each pond was basically the same in the earlier aquaculture stage and decreased in middle stage with a big difference, then rose again in the later stage.
文摘There is need for alternate quick-search of pathogens’distribution in community water sources,instead of the cumbersome“Escherichia coli detection.”Physical and chemical(physico-chemical)parameters were evaluated as veritable indicators of faecal Escherichia coli contamination of surface waters,using Adada River in Nigeria as case-study.Thirty-two(32)physico-chemical parameters were analyzed in the river(at specified geographical coordinates)for their quality and quantity and connected(using Pearson’s Correlation Analysis)with the distribution of the river’s isolated Escherichia coli.The 32 physico-chemical parameters consist of 11 cations,6 anions,7 physical properties,3 properties relating to oxygen and 5 properties relating to anions/cations.Physico-chemical indices from the analysis,revealed very significant positive correlation relationship of Escherichia coli with the presence of Mg(Magnesium)and K(Potassium)in the dry and rainy season,respectively.E.coli affinity tests(Kirby-Bauer Disc Diffusion)for these metals were also positive.Mg and K also showed significant positive Pearson’s possible paired correlation relationship.From this evaluation,potential index analysis indicated that Mg and K could serve as markers for the faecal bacteria indicators,and possible index for future monitoring of the potability of such surface water.The method is straight forward,cost effective,less cumbersome than other currently existing approaches.
