The pond bottom soil of Inceptisols mixed with Ultisols (I-U) and Vertisols (I-G) with theÂ proportion of (70:30); (50:50); (30:70) showed the improvement of clay fractionsÂ >30% compared with the control (100% Inceptisols). These mixtures were given basalÂ fertilizer (quail droppings manure with dosage of 2 tons/ha/month), Urea, and SP36.Â Cultivation system was divided into two stocked: fish ponds with 50 fish/m2 andÂ ponds without fish. The best mix with the basal fertilizer was further treated withÂ fertilization treatment (1 ton/ha/month of quail droppings manure) 3 times within 42Â days of larval rearing. Physical and chemical soil analyses showed an increase ofÂ total soil porosity (> 50%), decrease of SG, BD, and permeability (medium), pH > 5, theÂ CEC > 20 cmol (+) kg-1, and the C/N ratio < 6.5. The proportion of the best mix of 30%Â I : 70% U and 50% I : 50% G with 3 times of the fertilization frequency gave significantÂ improvement of water quality, chlorophyll-a, diversity of plankton, benthic algae, fishÂ growth, and total biomass. The presence of mineral montmorillonite on a mixture ofÂ 50% I : 50% G was a very good sign of the bottom soil fertility.
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