Bottom soil quality in Tilapia ponds of different age in Thailand

Abstract

Bottom soil samples were collected from 35 ponds in the vicinity of Samutprakarn, Thailand. Ponds ranged in age from 3 to 39 years and had been used continuously for production of tilapia. Liming materials had been applied in large amounts, and bottom soils of all ponds had pH above 7, low exchange acidity, and free carbonate. Pond soils often contained between 1% and 2% total sulphur, suggesting that they were potential acid–sulphate soils. However, acidity from sulphide oxidation was not expressed because carbonate in the soil neutralized it. Concentrations of total carbon seldom exceeded 4% and the average for organic carbon was 1.90%. The correlations between pond age and both total carbon and organic carbon concentration were weak (r=0.34 and 0.36 respectively). Concentrations of nitrogen in bottom soils did not differ with pond age and ranged from 0.1% to 0.3% with an average of 0.19%. The average ratio of concentrations of carbon and nitrogen was 11. Acid‐extractable phosphorus concentrations averaged 217 mg kg−1, but the phosphorus adsorption capacity averaged 768 mg kg−1 suggesting that soils still have considerable reserve capacity to adsorb phosphorus. Ponds can be used annually for semi‐intensive production of tilapia, and presumably other species, for many years without serious deterioration of bottom soil quality.

Relationship between organic carbon concentration and potential pond bottom soil respiration

“…Steeby et al (2004b) found that channel catfish ponds in Mississippi had an average organic carbon concentration of 1.77% with a range of 0.71-2.89%. In Thailand, the greatest organic carbon concentration in tilapia ponds ranging from 3 to 39 years of age was 3.39%; the mean for 35 ponds was 1.90% (Thunjai et al, 2004). Thus, the range in organic carbon concentration exhibited by samples in this study (Fig.…”

Alkalinity and Hardness: Critical but Elusive Concepts in Aquaculture

“…In tilapia ponds in central Thailand—where soils are naturally acidic—are typically limed during each crop. Alkalinities and hardnesses in these ponds usually are above 100 mg/L and some pond bottoms contain free carbonates from undissolved CaCO 3 (Thunjai et al ; Wudtisin and Boyd ).…”

“…In tilapia ponds in central Thailand -where soils are naturally acidic -are typically limed during each crop. Alkalinities and hardnesses in these ponds usually are above 100 mg/L and some pond bottoms contain free carbonates from undissolved CaCO 3 (Thunjai et al 2004;Wudtisin and Boyd 2006). Natural productivity is not as important in ponds with feeding as in fertilized ponds -except possibly soon after stocking fingerlings or postlarvae that cannot use pelleted feed efficiently (Boyd and Tucker 2014).…”

Evaluation of Composts from Agricultural Wastes with Fish Pond Sediment as Bulking Agent to Improve Compost Quality

“…A very recent study revealed the feasibility of fish pond sediment as a valuable soil amending agent for rice cultivation, which has high nitrogen content with C/N ratio <12 18, 19. Therefore, due to lower C/N ratio and relatively high density, fish pond sediment could be used as a bulking agent to speed up the composting of agricultural waste as well as, to enhance the density of the matured compost.…”