1Laws J A,Pain B F. Effects of method, rate and timing of slurry application to grassland on the preference by cattle for treated and untrealed areas of pasture[J]. Grass and Forage Science,2002,57(2):93- 104.
2Webb J, Pain B, Bittman S,et al. The impacts of ma- nure application methods on emissions of ammonia,ni trous oxide and on crop response A review[J]. Ag- ricult ure, Ecosystems and Environment, 2010,137 ( 1 ) : 39-46.
3Frame J. Improved Grassland Management [M]. UK: Crowood Press,1992 :237-257.
4McDonald P,Stirling A C, Henderson A R,et al. Fer- mentation studies on wet herbage[J]. Journal of the Science of Food and Agriculture, 1962, 13 ( 14): 581-590.
5Smith K A,Jackson D R,Misselbrook T H,et al. Re duction of ammonia emission by slurry application techniques[J]. Journal of Agricultural Engineering Re search, 2000,77 ( 3 ) : 277-287.
6Conaghan P, O' Kiely P, O' Mara F P. Conservation characteristics of wilted perennial ryegrass silage made using biological or chemical additives[J]. Jour- nal of Dairy Science,2010,93(2):628 -643.
7Unwin R J,Pain B F, Whinham W N. The effect of rate and time of application of nitrogen in cow slurry on grass cut for silage[J]. Agricultural Wastes, 1986, 15(4) :253 -268.