Content and distribution of mineral nitrogen forms in leached smolnitza under long-term nitrogen fertilization
1998
Panajotova, G. (Institut po Pamuka i Tv"rdata Pshchenitsa, Chirpan (Bulgaria)) | Karev, K.
It was estabilished that the content of mineral nitrogen in both soil layers and total for 0 - 60 cm varied depending on the nitrogen fertilization and on weather conditions. The content of NH4-N before autumnal N application in surface for check was 0.9-3.3 kg/da. At all applied N rates NH4-N increased and at high N level reached to 2.7-9.6 kg/da. In the 30-60 cm soil layer the values were 0.9-3.9 and 1.8-4.8 kg/da respectively. At the end of the durum wheat vegetatin (VII) the content was considerable higher. The contants of NO3-N were lower compared with the NH4-N. The mineral nitrogen in 0-60 cm increased with incresing of N level. In starting samples (VII.1988) for the check was 15.6 kg/da. At applied low N rate increased with 48.1% at the moderate - with 88.8% and at the high N rate - with 103.8%.
显示更多 [+] 显示较少 [-]