The Effects Of The Soil Cellulose-decomposing Bacteria And Its Enzyme Activity In Different Tillage Measures

On basis of the principles of soil microbiology,changes of different tillage experiments about the intensity of cellulose-decomposing,the population of cellulose-decomposing bacteria,the population of cellulose-decomposing fungi and soil cellulase in pea field and wheat field were studied in this four treatments(No-tillage and straw cover(NTS), plough with straw incorporated(TS), No-till without straw (NT), conventional cultivation(T) in Dingxi of the semi-arid areas of the Loess Plateau. The main research results are showed as follows:1 The effects of cellulose-decomposing intensity in different tillage measures:1) In two rotation sequences, the cellulose-decomposing intensity in No-tillage treatment is higher than the cellulose-decomposing intensity in conventional cultivation treatment; And compared with the cellulose-decomposing intensity of straw conventional cultivation, the cellulose-decomposing intensity of No-till without cover increase about 12.85%,16.58%,30.72% in0-5cm, 5-10cm and 10-30cm on average.2) In two rotation sequences, the cover treatment can increase the cellulose-decomposing intensity in0-5cm. And compared with the cellulose-decomposing intensity of plough with straw incorporated, the cellulose-decomposing intensity of No-tillage and straw cover increase about 59.26%,14.03%,9.03% in0-5cm, 5-10cm and 10-30cm on average.3) In two rotation sequences, the cultivation effect has have very significant influence(P≤0.01) to the cellulose-decomposing intensity. But cover effect and mutual effect of cultivation and cover only have very significant influence(P≤0.01) to the cellulose-decomposing intensity in wheat field.4) In two rotation sequences, the deepper of the layer, the higher of the cellulose-decomposing intensity.5) Compared with 2006, the cellulose-decomposing intensity of the W/P/W rotation sequence increases in 2007.However the P/W/P rotation sequence changes in different.2 The effects of cellulose-decomposing bacteria population in different tillage measures:1) In two rotation sequences, the population of cellulose-decomposing bacteria in No-tillage treatment is higher than the population of cellulose-decomposing bacteria in conventional cultivation treatment; And compared with the population of cellulose-decomposing bacteria of straw conventional cultivation, the population of cellulose-decomposing bacteria of No-till without cover increases about 36.07%,10.19%,52.22% in0-5cm, 5-10cm and 10-30cm on average.2) In two rotation sequences, the cover treatment can increase the population of cellulose-decomposing bacteria in5-10cm. And compared with the population of cellulose-decomposing bacteria of plough with straw incorporated, the population of cellulose-decomposing bacteria of No-tillage and straw cover increase about 9.89%,18.83%,3.15% in 0-5cm, 5-10cm and 10-30cm on average.3) In two rotation sequences, cover effect ,the cultivation effect have very significant influence(P≤0.01)the population of cellulose-decomposing bacteria. But mutual effect of cultivation and cover only has very significant influence(P≤0.01) to the population of cellulose-decomposing bacteria in wheat field.4) In two rotation sequences, the deepper of the layer, the lower of the population of cellulose-decomposing bacteria.5) Compared with 2006, the population of cellulose-decomposing bacteria in two rotation sequences increase evidencely.3 The effects of cellulose-decomposing fungi population in different tillage measures:1) In two rotation sequences, the population of cellulose-decomposing fungi in No-tillage treatment is higher than the population of cellulose-decomposing fungi in conventional cultivation treatment; And compared with the population of cellulose-decomposing fungi of straw conventional cultivation, the population of cellulose-decomposing fungi of No-till without cover increases about 10.53%,3.61%,12.99% in0-5cm, 5-10cm and 10-30cm on average.2) In two rotation sequences, the cover treatment can increase the population of cellulose-decomposing fungi in0-5cm. And compared with the population of cellulose-decomposing fungi of plough with straw incorporated, the population of cellulose-decomposing fungi of No-tillage and straw cover increase about 14.94%,2.5%,-2.41% in0-5cm, 5-10cm and 10-30cm on average.3) In two rotation sequences, the cultivation effect has very significant influence(P≤0.01)the population of cellulose-decomposing fungi. And cover effect only has very significant influence(P≤0.01) to the population of cellulose-decomposing fungi in pea field.4) In two rotation sequences, the population of cellulose-decomposing fungi changes in different in three layers.4 The effects of the soil cellulase in different tillage measures:1) In two rotation sequences, the soil cellulase in No-tillage treatment is higher than soil cellulase in conventional cultivation treatment; And compared with the soil cellulase of straw conventional cultivation, the soil cellulase of No-till without cover increases about 14.08%,6.18%,16.03% in0-5cm, 5-10cm and 10-30cm on average.2) In two rotation sequences, the cover treatment can increase the soil cellulase in0-5cm. And compared with the soil cellulase of plough with straw incorporated, the soil cellulase of No-tillage and straw cover increase about 7.36%,2.13%,4.11% in0-5cm, 5-10cm and 10-30cm on average.3) In two rotation sequences, cover effect ,the cultivation effect have very significant influence(P≤0.01)to the soil cellulase. And only mutual effect of cultivation and cove has very significant influence(P≤0.01) to the soil cellulase in pea field.4) In two rotation sequences, the deepper of the layer, the lower of the soil cellulase.