Shrimp Pond Waste: A Source of Manure for Coconut
Kalpani Wijayasinghe and Indika Herath
Abstract
Background: Pond waste from shrimp farming in brackish-water is a solid waste that has no identified use, rather become an environmental problem. This study aims to evaluate the potential use of shrimp pond waste as a manure for monoculture coconut plantations.
Methods: The treatments were T1- No fertilizer, T2- Inorganic fertilizer (N, P, K and Mg) and T3- Raw Shrimp Pond Waste (RSPW) with Muriate of Potash. Treatments were arranged in a Randomized Complete Block Design with 3 replicates. After treatment application the soil properties were evaluated by analysing soil pH, electrical conductivity (EC), Organic Carbon (OC), Total N, Available P, Exchangeable K and soil bulk density. Additionally, Water holding capacity (WHC) of soil as a result of addition of RSPW was also evaluated. Foliar nutrient levels of palms were also analysed for primary nutrients, six months after treatment applications.
Results: Results showed that treated soils with RSPW has been given the highest EC (0.63 dS/m) compared to all other treatments. There was no significant difference among the treatments in soil pH, OC, total N and exchangeable K. Available P is also not significantly different between T2 and T3, but significantly higher than the control. The WHC of soil increased by 31 % as a result of adding RSPW. The foliar nutrient levels were higher than critical values in T2 and T3.
Conclusions: According to the results, SPW has the potential of using as a fertilizer for coconut while long term effects need further investigations.
Keywords: Coconut, Organic Fertilizer, Shrimp Pond Waste, Soil Nutrients, Soil Properties