02969naa a2200457 a 450000100080000000500110000800800410001902200230006002400420008310000210012524501030014626000090024952016860025865000220194465000240196665000220199065000190201265000120203165000230204365000160206665000160208265000100209865000110210865300240211965300220214365300220216565300310218765300210221865300190223965300230225865300140228165300250229565300210232065300200234170000210236170000200238270000210240270000200242370000250244377300430246821289792021-12-16       2021    bl uuuu     u00u1 u    #d  a1807-8621 (Online)7 a10.4025/actasciagron.v43i1.467642DOI1 aESPINDULA, M. C.  aAmmonia loss from protected urea in soil under different irrigation depths.h[electronic resource]  c2021  aThis study presents an evaluation of the viability of using protected urea under different irrigation depths to reduce nitrogen losses caused by the volatilization of ammonia (NH3) under the conditions of the Southwestern Amazon. The study was carried out at the Experimental Station of Embrapa Rondônia, in the municipality of Porto Velho, Rondônia State, Brazil. The experiment was conducted in a Red-Yellow Latosol and arranged in a 5 x 6 factorial design consisting of a combination of five treatments (N sources) with six irrigation depths. The sources of N were as follows: 1) urea (45.5% N); 2) urea (44.3% N) + 0.15% copper and 0.4% boron; 3) urea (45% N) + NBPT; 4) urea (43% N) + sulfur (1%); and 5) control (without N). The irrigation depths were 0, 5, 10, 15, 20, and 25 mm. The results showed that, regardless of the use of urease inhibitors, an irrigation depth of 10 mm is suitable for incorporating urea into the soil and stabilizing N losses from NH3 volatilization. NBPT is the most efficient inhibitor under nonirrigated conditions. All N sources promote increases in the concentrations of nitric and ammonia nitrogen in the soil. In the first 15 days after fertilizer application, the highest concentrations of ammonium were in the 0 - 10 cm and 10 - 20 cm soil layers, and NBPT showed the highest ammonium content compared to that of the other sources in the 0 - 10 cm layer. The nitric nitrogen content in the soil was slightly influenced by the irrigation depth in the first 15 days after fertilizer application. However, the ammonia nitrogen content decreased exponentially with the increase in irrigation depth due to the movement of ammonia in the soil.  aAmmonium nitrogen  aDemonstration farms  aUrease inhibitors  aVolatilization  aAmônia  aCampo Experimental  aIrrigação  aNitrogênio  aPerda  aUréia  aAmazônia Ocidental  aEmbrapa Rondônia  aIrrigation depths  aLatossolo Vermelho-Amarelo  aPorto Velho (RO)  aProtected urea  aRed-Yellow Latosol  aRondônia  aSouth Western Amazon  aUréia protegida  aVolatilização1 aRODOVALHO, G. M.1 aMARCOLAN, A. L.1 aBARBERENA, I. M.1 aCIPRIANI, H. N.1 aARAÚJO, L. F. B. de  tActa Scientiarumgv. 43, e46764, 2021.