4Aulakh M S, Doran J W, Mosier A R. Soil denitrification-significance, measurement, and effect of management [J]. Advances in Soil Science, 1992,18:1-57.
5El-Ghamry A M, Xu Jian-min, Huang Chang-yong. Influence of herbicides on microbial biomass and nitrogen mineralization in soils [J]. J. of Zhejiang Univ. (Agric. and Life Sci.), 1999,25(6): 639-644.
6Cai G X, Chen D L, Ding H, et al. Nitrogen losses from fertilizers applied to maize, wheat and rice in the North China Plain [J]. Nutrient Cycling in Agroecosystems, 2002,63:187-195.
7Weier K L. Nitrogen use and losses in agriculture in subtropical Australia [J]. Fertilizer Research, 1994,39:245-257.
8De Klein C A M, Van Logtestijn R S P. Denitrification in grassland soils in the Netherlands in relation to irrigation, N-application rate, soil water content and soil temperature [J]. Soil Biol. Biochem., 1996,28(2):231-237.
9ANDERSON J P E,DOMSCH K H A.Ohysiological method for the quan-titative measurement of microbial biomass in soils[J].Soil Biology and Bi-ochemistry,1978,10(3):215-221.
10Zabinski C A, Cannon J E. Effects of recreational impacts on soil microbial communities [J]. Environmental Managemenl,1997, 21:233-238.