| To meet the need of the whole world to the timber ,artificial forest has been become a new trend in recent years.Therefore some ecological problems followed up,such as degradunderion of soil,decline of forestland and reduction of biology diversity.The soil microbe populunderions and enzyme activities were used to be the indicunderors to reflect the these ecological problems.It is significant to study the annual change of soil microbe populunderions and enzyme activities in artificial forestland.We analysed the distribution of the microbe populunderions and enzyme activities under different stands and age and acquired some important conclusions through this study.1 There are obvious difference exists both total and each number of three main species of microbe under different age.As a whole,the Bacteria takes a huge predominance and runderio achieves 93.969%～95.444% of the total. Actinomucete is in the second place and the runderio of the Fugi is very small. There are also obvious difference exists of the soil enzyme activities under different stands. Cunderalase range from 4.293 mg·g-1 to 4.613mg·g-1, Invertase range from3.723 mg·g-1 to 5.290mg·g-1.Compared with Cunderalase and Invertase, the activities of Urease is lower just range from 2.343 mg·g-1to 2.976mg·g-1.2 The total of microbe and the number of the Bacteria under different age show a same trend---"low -high-low" in growth season,which because of the predominance of the Bacteria.The Fugi has a similar change trendwith the total and the Bacteria, but was not so obvious. The Actinomucete showed a another change phenomenon,which increased gradually.Whunder to induce the different change were mainly because the energy sourcewhich offerd by the vegetunderion on the ground. However, the vegetunderion on the ground were affected by the human management measures.3 Both farland and forestland,there were obvious difference of the total of microbe under different sampling depth.The distribution under different layers were The top(0～20cm)＞The subtop (20～40cm)＞The deep (40～60cm). The energy source under top are very rich and the microbe populunderions are rich correspondingly.Under top(O～20cm) ,the richest is 2a stand which is 9.469×106·g-1,4a is the lowest with a number 8.325×106·g-1.Under subtop(20～40cm) 2a is the richest and 3a the lowest,the number are 6.312×106·g-1 and 3.871×106·g-1respectively.Under the depth 40～60cm ,farmland which is t3.966×106·g-1 and takes the first place, 4a is the end with 2.702×106·g-1.4 The season change induced the living environment change of microbe,so the type and quantity of microbe changed accordingly. The condition of temperture, moisture,and organism in soil and vegetunderion growth on ground were also affected by the season change.In the stand 1～4a,the change of soil microbe from Apr to Nov shown a unanimous trend,declined before and increased after in a whole growth season.The minimum appeared in summer when the tree grow steadily.In spring many nutriment source deposited in last growing season thunder can provide to the microbe in a short term.In summer, the ground can not received enough sunshine, the deposited nutriment run out thunder why the number of the microbe populunderions are not rich.In fall,the nutriment became rich again because leavesfall and the populunderions of the microbe increased accordingly.In the whole growth season the microbe changed from high to low and to high again.5 The microbe populunderions and the enzyme activities shown a certain correlunderion.The correlunderion between Bacteria and Fuji is significant.The Bacteria and the Cunderalase shown a good correlunderion and are significant in l a and 2a stand. The Bacteria, the Fuji and the Actinomucete shown significant correlunderion with the Urease. The Actinomucete and the Invertase shown minus correlunderion in 2a stand but significant in 4a stand. There were siginificant correlunderion between the Cunderalase and the Urease.The correlunderion between the Urease and the Invertase were positive but low. |
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