Effect of Sodium Chiloride Application on Nitrification Rate in Coconut Growing Soils
No Thumbnail Available
Date
2015
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Uva Wellassa University of Sri Lanka
Abstract
Nitrification is the main transformation that governs the pool size of the two plant available N forms; NH4+ and NO3- in soil. A study was conducted to identify the effect of NaC1 application together with KC1 on nitrification rates of coconut growing soils and to evaluate the NO3- -N losses with respect to chloride application under rainfall simulated conditions.
The experiment was conducted. a.s a pot experiment using soils of Madampe soil series with five treatments i.e. (i) Zero fertilizer application (NF), (ii) Adult palm mixture (APM) for Coconut in intermediate zone, (iii) APM + 1 kg NaCl/palm/year, (iv) APM
2 kg Naapalm/year, (v) APM 3 kg NaCl/palm/year with three replicates (n = 3). Soil
, ,
sampling were carried out at the 2nd 4th 6th , and 10th weeks after imposing the
treatments and they were assessed for pH, electrical conductivity, NH4+ -N, NO3- -N, Nat, Cr, Kt contents, ammonium oxidizer and nitrite oxidizer population and potential nitrification rates. Soils were leached simulating rainfall conditions at the 6th and 12th weeks after treatment application and the leachate was analyzed for NH4+-N and NO3--N contents.
Soil treated with 2 k.g NaC1 and 3 kg NaCi/palm/yr showed significantly (p < 0.05) higher NH4+ -N content throughout the experimental period where as significantly (p < 0.05) lower soil. NO3- -N content was observed in NF followed by APM + 3 kg NaCl/palm./yr during the whole experimental period except in 2 weeks after imposing the treatments. Potential nitrification rates ranged from 1.27 to 2.5 land 0.68 to 3.65 and 0.13 to 1..1.5 1.tgNO3- -N/g dry soil/h in 211d, 6th and • e weeks after treatment application respectively. The soil nitrification rates in the treatment of APM + 3 kg NaCl/palm/yr were significantly reduced with the time. Application of NaCl showed reduction in leaching losses of NO -N and NH4+ -N up to 6th week but, it was not effective in. 12 weeks after treatment application.
As a conclusion, it was obtain that, addition of extra CF as MCI helps decrease the NO3- -N content in the soil. It was also reflected by high NH4+ -N content in the Cr treated soils and leachate. Moreover, application of 3 kg NaClipalinlyr with APM has an effect of nitrification rate as well as NO3- N content.
Key words: Ammonium, leaching loss, nitrate, nitrogen, nitrifiers, potassium
chloride
Description
Keywords
Palm and Latex Technology and Value Addition Degree Programme ( PLT)