| The research was conducted from 2000 to 2002 in Root System Lab, College of Horticulture, Shandong Agricultural University. It utilizes the seedlings of M- hupehensis Rehd. As testing materials planted in pots and PVC tubes, and uses the compound of peat and vermiculite as basic media to which are first added chicken manure, sheep manure, peanut straws and the mixture of chicken manure and sheep manure respectively and then added the compound fertilizer with N,P,K respectively, or adopts soil to which is added compound fertilizer,The thesis explores annual changes of various organic material decomposition, of mineral nutritious elements, and of microorganism quantity. And it further probes into the effect of different organic materials on the life span and growth speed of new roots, respiration intensities of white roots and brown roots of the root system structure at different stages, absorption dynamic parameter of 32P, absorption distribution of N and absorption and distribution of 15N at final stages, difference of photosynthetic rate of leaves and changes of root morphological features and organism quantity.The results of the research are as follows.1. The decomposition rates (weight loss rates ) of different organic materials vary within a year. Chicken manure turns out to decompose faster at earlier stages of which 86 percent of organic matter has been decomposed, and loses less weight at finals stages. Sheep manure disintegrates more slowly than chicken manure at first and it gradually develops faster, and it has a tendency to decompose all the year around. At first stage, peanut straws give out 80 percent of the total decomposition. The number of microorganism. Varies greatly in different treatments. The number of bacteria, fungi and actinomycetales in the earlier treatment of chicken manure is more than that in sheep manure, and the number of microorganism in chicken manure treatment at final stage is fewer than diat in sheep manure, The concentration of mineral nutritious elements in theearlier treatment of chicken manure is higher than that in sheep manure, at final stage the case is quite contrary, while the concentration of mineral elements and the number of microorganism in mixture of chicken manure and sheep manure keeps a higher level in the whole year.2. Applying organic materials to the basic media lengthens the life span of roots to certain extent. The life span of roots in chicken manure treatment is the longest, which lasts 48 days, followed by sheep manure treatment (40 days), treatment of the mixture (34 days) peanut straw treatment (29 days), CK (26 days) and soil cultivation (21 days). The speeds of root growth differ in different treatments. Roots grow fastest in the mixture. Different seasons see a contrary growth rate between the treatments of chicken manure and sheep manure. In summer the growth rate in the former is faster than that in the latter, and in autumn that in the latter faster than that in the Latter, and in autumn that in the latter faster than in the former. And the root growth in all the treatments show a faster rate in summer. At earlier stage weight of white roots in chicken manure treatment is more than that in sheep manure, and at final stage the weight of white roots in the former is less than that in the latter, while in the treatment of the mixture the white roots are the heaviest all the year round.3. Respiration intensity of roots is affected by the types Of organic materials. The intensity in the mixture is the highest, the second to follow being that in sheep manure and the lowest being that in peanut straw treatment, compared with CK (in summer). Compared with CK, the respiration intensities of the whole root system in the treatments of the mixture, of chicken manure, of sheep manure and of peanut straws have increased by 101 percent, 56 percent, 31 percent and 25percent respectively.In autumn the respiration intensity in sheep manure is higher than that in chicken manure.4. The respiration intensity of absorbing roots, growing ro...
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