Nitrogen loading levels affect abundance and composition of soil ammonia oxidizing prokaryotes in semiarid temperate grassland

Abstract

Purpose: Global nitrogen deposition has profound impact on the terrestrial ecosystem including the semiarid temperate grassland, causing vegetation community shifts and soil acidification. Little is known regarding the effect of nitrogen (N) deposition on the belowground microbial communities. This study aimed to examine the response of ammonia-oxidizing bacteria (AOB) and archaea (AOA) to added N in semiarid temperate grassland. Materials and methods: We studied the changes of AOB and AOA by using molecular techniques targeting amoA genes along a urea fertilization gradient, i. e., 0, 1, 2, 4, 8, 16, 32, 64 g N m-2 year-1, in a 6-year field experiment of semiarid temperate grassland, Inner ..