Balancing carbon/nitrogen ratio to improve nutrients removal and algal biomass production in piggery and brewery wastewaters

Atrazine, a chlorinated s-triazine group of herbicide is one of the most widely used pesticides in the World. Due to its extensive use, long half-life and various toxic properties, it has very high environmental significance. Up to 22 mg l-1 of atrazine was found in ground water whereas permissible limit of atrazine is in ppb level in drinking water. As per Indian standard there should not be any pesticide present in drinking water. Among many other treatment processes available, Incineration, adsorption, chemical treatment, phytoremediation and biodegradation are the most commonly used ones. Biological degradation of atrazine depends upon various factors like the operating environment, external carbon and nitrogen sources, carbon/ nitrogen ratio (C/N), water content and the bacterial strain. Although, general atrazine degradation pathways are available, the specific pathways in specific conditions are not yet clearly defined. In this paper extensive review has been made on the occurrence of atrazine in surface and ground water bodies, probable sources and causes of its occurrence in water environment, the toxicity of atrazine on various living organisms and its removal by biological processes.

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The Organic Matter and Nitrogen Content and Carbon-Nitrogen Ratio of Cecil Soil as Influenced by Different Cropping Systems on Classes II, III, and IV Land

Soil Science Society of America Journal ◽

10.2136/sssaj1950.036159950014000c0046x ◽

1950 ◽

Vol 14 (C) ◽

pp. 203-208

Author(s):

G. W. Gosdin ◽

Matthias Stelly ◽

W. E Adams

Keyword(s):

Organic Matter ◽

Nitrogen Content ◽

Cropping Systems ◽

Carbon Nitrogen Ratio ◽

Nitrogen Ratio

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Effects of Organic Fertilizer on Bok Choy Growth and Quality in Hydroponic Cultures

Agronomy ◽

10.3390/agronomy11030491 ◽

2021 ◽

Vol 11 (3) ◽

pp. 491

Author(s):

Kazuki Kano ◽

Hiroaki Kitazawa ◽

Keitaro Suzuki ◽

Ani Widiastuti ◽

Hiromitsu Odani ◽

...

Keyword(s):

Plant Root ◽

Oxygen Deficiency ◽

Organic Fertilizer ◽

Corn Steep Liquor ◽

Ascorbic Acid Content ◽

Growth And Yield ◽

Significant Difference ◽

Carbon Nitrogen Ratio ◽

Nitrogen Ratio ◽

Steep Liquor

Effects of corn steep liquor (organic fertilizer, OF) and conventional chemical fertilizer (CF) on the growth and yield of bok choy (Brassica rapa var. chinensis) in summer and autumn hydroponic growing systems were compared. When OF and CF were applied with the same amount of total nitrogen in summer cultivation, there was no significant difference between yields; however, the growth rate in OF was slower than in CF. When OF was applied with twice the amount of nitrogen in CF (OF2), bok choy growth and yield were significantly inhibited in summer cultivation, likely owing to dissolved oxygen deficiency and different rates of nitrification and nitrogen absorbance by the plant root. Although the contents of potassium, calcium, and magnesium in bok choy showed no difference among the three treatments in both cultivation seasons, the carbon/nitrogen ratio tended to be higher in OF and OF2 than in CF. Lower nitric acid and higher ascorbic acid content was found in OF and OF2 than in CF. Overall, our results suggest that a comparable yield is expected by using the same nitrogen amount with a conventional recipe of chemical fertilization in autumn cultivation. However, further improvement of hydroponic management is needed in summer cultivation.

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