|
|
|
|
|
Juan,Y.H; Chen,Z.H; Chen,L.J; Wu,Z.J; Wang,R; Sun,W.T; Zhang,Y.L. |
The kinetic characteristics of soil urease have attracted great attention, but little information was available on its kinetic and thermodynamic behaviors as affected by urease inhibitors and temperature. With black soil (Pachic Udic Mollisol) in Heilongjiang Province of Northeast China as a test soil, an incubation test was conducted to investigate the effect of urease inhibitors (hydroquinone, HQ; phenyl phosphorodiamidate, PPD; N-(n-Butyl) thiophosphoric triamide, NBPT) on kinetic and thermodynamic behaviors of soil urease at 10°C, 20°C and 30°C. The results showed that all tested inhibitors increased Km and decreased Vmax, behaving as mixed inhibitors to soil urease. With increasing temperature, the Km and Vmax values increased significantly. With... |
Tipo: Journal article |
Palavras-chave: Meterkinetic paras; Thermodynamic parameters; Soil urease; Urease inhibitors; Temperatures. |
Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912010000100001 |
| |
|
|
Juan,Y.H; Chen,L.J; Wu,Z.J; Wang,R. |
With black soil (Pachic Udic Argiboroll) of Northeastern China as the test object, an incubation test was conducted to investigate the effects of urease inhibitors, hydroquinone (HQ), phenyl phosphorodiamidate (PPD) and N-(n-Butyl) thiophosphoric triamide (NBPT), on the kinetic characteristics of soil urease under normal moisture and waterlogged conditions, aimed to study the changes of catalytic potential of soil urease and the inhibition mechanisms. The results showed that test urease exhibited typical Michaelis-Menten kinetic behaviors, and all test inhibitors increased the Km and decreased the Vmax of soil urease, behaving as mixed inhibitors to soil urease. Under both normal and waterlogged conditions, compared with HQ, PPD and NBPT made Km increase... |
Tipo: Journal article |
Palavras-chave: Kinetic parameters; Mixed inhibition; Moisture regime; Soil urease. |
Ano: 2009 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912009000200004 |
| |
|
|
Ma,X. Z; Chen,L. J; Chen,Z. H; Wu,Z.J; Zhang,L.L; Zhang,Y.L. |
The purpose of this study was to measure the effects of different land uses on soil glycosidase activities (a- and (β-glucosidase, α- and (β-galactosidase), water soluble organic carbon (WSOC) and their relationships. Glycosidase activities showed significant differences under different land use types, the highest one was woodland. (β-glucosidase had the highest activity among the four glycosidases. The activities of these glycosidases decreased with increasing soil depth, being all significantly affected by change of soil depth. Except grassland, the four glycosidase activities intercorrelated each other. Woodland had the highest content of WSOC in the soil depth of 0-20 cm and at increasing soil depth, WSOC content... |
Tipo: Journal article |
Palavras-chave: Glycosidase activities; Water soluble organic carbon; Land use; Soil depth. |
Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912010000200001 |
| |
|
|
Zhang,Y.L; Chen,L.J; Chen,Z.H; Sun,C.X; Wu,Z.J; Tang,X.H. |
No tillage is being populanzed for the rainfed maize production in Northeast China. In order to evalúate its effects on the nutrient contents and enzymatic charactenstics in upland soils of Northeast China, surface (0-20 cm) meadow brown soil samples were collected from the plots under no tillage and conventional tillage in a 7-year field experiment under maize cropping in Shenyang, with the soil pH, contents of total C, N, P and S and available N, activities of α- and (β-galactosidase, α- and (β-glucosidase, urease, protease, phosphomonoesterase, phosphodiesterase, and arylsulphatase, and kinetic parameters of (β-glucosidase, protease, phosphomonoesterase, phosphodiesterase, and arylsulphatase determined.... |
Tipo: Journal article |
Palavras-chave: Conservation tillage; Conventional tillage; Soil enzyme activity; Enzyme kinetic properties. |
Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912010000200006 |
| |
|
|
|