@article {KNZ00671,
	title = {Changes in enzyme activities and microbial biomass of tallgrass prairie soil as related to burning and nitrogen fertilization},
	journal = {Soil Biology \&amp; Biochemistry},
	volume = {31},
	year = {1999},
	pages = {769 -777},
	abstract = {Microbial biomass and enzyme activities are affected by management practices and can be used as sensitive indicators of ecological stability. Microbial biomass C (MBC), microbial biomass N (MBN) and eight enzyme activities involved in the cycling of C, N, P and S were studied in the surface (0{\textendash}5 cm) of an Irwin silty clay loam soil (fine, mixed, mesic, Pachic Arguistoll) in a tallgrass prairie ecosystem. Treatments of annual spring burning and N fertilization were initiated in 1986 and encompassed: (1) unburned{\textendash}unfertilized, (2) burned{\textendash}unfertilized, (3) burned{\textendash}fertilized, and (4) unburned{\textendash}fertilized. Activities of dehydrogenase, β-glucosidase, urease, deaminase, denitrifying enzyme, acid phosphatase, alkaline phosphatase, and arylsulfatase were assayed. Long-term burning and N fertilization of the tallgrass prairie soil reduced MBC and MBN relative to the unburned{\textendash}unfertilized treatment. The effects of burning and N fertilization varied among the enzymes and the time of sampling. Long-term burning significantly (P<0.05) increased activities of urease and acid phosphatase, but decreased activities of β-glucosidase, deaminase and alkaline phosphatase. Long-term N fertilization significantly increased activities of β-glucosidase and acid phosphatase but decreased urease activity. This study found that several soil enzyme activities can be used as indicators of ecological changes caused by N fertilization and long-term burning management practices. The relevance of these changes in surface soil to the long-term sustainability of this ecosystem needs further evaluation.},
	keywords = {LTER-KNZ, tallgrass prairie},
	doi = {10.1016/S0038-0717(98)00177-1},
	author = {Ajwa, H.A. and Dell, C.J. and C. W. Rice}
}
