%A WANG Feng, CHEN Yuzhen, YOU Zhiming, WU Zhidan, JIANG Fuying, ZHANG Wenjin, WENG Boqi %T Effects of Different Nitrogen Application Rates on Nitrification and pH of Two Tea Garden Soil %0 Journal Article %D 2015 %J Journal of Tea Science %R 10.13305/j.cnki.jts.2015.01.016 %P 82-90 %V 35 %N 1 %U {https://www.tea-science.com/CN/abstract/article_849.shtml} %8 2015-02-15 %X Two tea garden soils (yellow soil and red soil) derived from Wuyishan City were incubated at 25℃with a soil moisture content of 60% water holding capacity (WHC) for 46 days. The dynamics of nitrification and pH of soil after urea application at different rates were measured. The results show that urea is hydrolyzed fast (2-6βd) with a high nitrification activity in yellow soil. However, the urea is hydrolyzed relatively slow (16βd) in red soil. The nitrification rate in two tea garden soils are 81.32% and 73.48% respectively, and the nitrification activity in yellow soil is significantly higher than that in red soil (P<0.05). With or without nitrogen application, changing tendency of the contents of NO3-N in two tea garden soils show as ‘J’ type with an obvious delay step for 11-16 days. The nitrification in these tea garden soils follows the exponential model N=N0ekt(P<0.01). Compared with the control treatment, the net amount of nitrified nitrogen, net nitrification rate and k value increase with the urea N application rates, however, the nitrification rates decreased with the urea N application rates. With or without Nitrogen Application, the N2O fluxes from yellow tea garden soil were higher than those from red tea garden soil(P<0.05). Compared with the control treatment, soil pH decreased by 0.16-0.52 and 0.11-0.25 pH units with the urea N application rates. These results indicated that two highly acidic tea garden soils showed high nitrification activity(delay step were 11-16 days), and be conducive to absorb NH4+-N. Urea application could decrease soil pH, and the nitrogen application rate is one of the main factors accelerating acidification of tea garden soil.