| ABSTRACTWith the acreage of 3,868,300 hectares making up 71.89% of the national total bamboo forest area or 2.13% of the total national forest acreage, Moso bamboo (Phyllostachys edulis) has been a significant forest species for the ecological construction and farmer income addition polices in the collective forest areas of southern China and fertilization as a key technical measure of forest management has been practiced on growing scale. To explore improved scientific Moso bamboo fertilization method, field experiments and household surveys were designed in Anji, Longquan, Suichang etc of Zhejiang Province and Yong'an of Fujian Province to study the morphological and silviculture ecology responses of Moso Bamboo to the widely practiced model fertilization methodology to put forward and verify the economically viable and soil ecological performance assured Moso bamboo soil-testing recommended fertilization methodology. The research had the following main conclusions.(1) After the model fertilization the amount of single-culm leaves of the Moso bamboo forest increased by 24% and the leaf area index (LAI) increased significantly. During the stabilized period, the model fertilization stands had the LAI of 7.67 which was 1.48 higher than the control. Model fertilization did not have significant impact on the single-leaf area, the thousand-leaf weight and the gravity center of the leaf canopy leaves. The added LAI strengthened the photosynthetic capability for higher organic matter accumulation for raised biological output and economic production of Moso bamboo forest.(2) After the model fertilization, the economic morphological features of Moso bamboo culm changed slightly and the biological output and economic production increased as the result of the raised bamboo stands DBH and density. Model fertilization had insignificant impacts on the morphological features of the culm length, amount of culm inter-node sections, the culm inter-node length, the taper degree and culm wall thickness, and had significant impact on the culm weight and below-branch culm height. Specifically, after the model fertilization, the culm weight decreased by 6.8%, the below-branch culm height decreased by 17.3% while the average bamboo stands density, the average DBH and the young bamboo culm quantity increased significantly by 45.6%,4.59% and 43% respectively.(3) The model fertilization was helpful for the maintenance of soil biological communities, and thus contributive to maintaining forest land ecological quality. By contrasting the soil nutrient level of three land use types namely the long-term model fertilization (OM), traditional style N fertilization (CM) and no fertilization (UM), the OM was the highest. In addition, the enumerated bacterium quantification of plain plate indicated that the soil bacteria community quantity OM>UM>CM. The established 16S rDNA genomic library of soil microorganism indicated the total DNA enzyme cutting variation levels OM>UM>CM. The study of Shannon-Wienner index, Simpson index, abundance degree and uniformity levels of the total DNA genomic library all showed that the OM was superior in general to other two samples.(4) The Moso bamboo forest has comparatively higher capability of soil and water conservation. The model fertilization runoff and nutrient of Moso bamboo forest produced an acceptably high runoff amount which did not form regional level negative environmental impact. However, the long-term pressure of applying fertilizer for good regional environment existed. The study showed that the rainfall, rainfall intensity, bamboo forest density affect runoff levels and the ditch style fertilization mode had higher erosion than the hole type fertilization mode by the model fertilization. The measured Moso bamboo forest runoff coefficient was between 0.0007-0.001,with the nitrogen runoff was between 0.106-0.153 kg/hm2;the P between 0.001-0.002 kg/hm2 which were both at comparatively low levels.(5) The Zhejiang Moso bamboo management technology were economic revenue oriented, which brought about immense ecological pressure to the forest ecosystem. The nutrient condition of bamboo forest soil needed to be improved. The average pH value of Moso bamboo land of the province ranged from 4.66 to 5.03 while the soil nutrients of organic matter, whole nitrogen, available nitrogen, available phosphorus and available potassium had high discrepancies. For most areas, the soil needs supplementation of P and N while the available potassium is generally higher. Meanwhile, by nutrient variation analysis to 10a-30a managed Moso bamboo forest soil, it showed that applying fertilizer as far as the applying time, dosage and operation manners etc were concerned, reduced the correlation of soil nutrient and the reduction degree differed among the forest management activities. Nevertheless, as the managed time went on, the distribution of soil nutrient contents tended to be more uniform.(6) Application of Moso bamboo soil-testing formulation recommendation fertilization on large scale was a process of technical standardization and informationization. Such technology should have explicit principles, simplified operational procedures and farmer technology development participation arrangements to raise fertilization efficiency preserve land quality and mitigate the environmental risks. The pilot program of soil-testing formulation recommendation fertilization in Suichang County incorporated such participation and integrated management measures. Consequently, the cost-benefit ratio dropped from 1:2.3 to 1:2.99 and the used fertilizer quantity decreased by 4-23%, which proved that the fertilization of the soil-testing formulation fertilization was contributive to social, economic and environmental coordinated sustainable Moso bamboo forest management.
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