Study On The Rhythm Of Shooting And Growing Into Culms And Structure Regulative Techniques Of Pulp Sympodial Bamboo Forest

In order to improve cultivating technology level of pulp bamboo forest,three sympodial bamboo plantations (D.farinosus, B.pervariabilis×D.daii, B.rigida) growing in southern Sichuan were taken for research object.Growth characteristics and forest structure regulative were researched. There are following aspects.1)In order to provide scientific basis for prediction of yield and biomass, culm feature and biomass of three bamboo were surveyed.The result showed that the correlation among DBH and the other culm feature factors,such as culm height, culm weight, whole node and biomass of organs reached significant level. prediction of yield and biomass could be compiled by regression equations.The result of biomass allocation showed that above-ground biomass account for more than 80% of the total biomass ,clum biomass account for 66.8～68.1% of the total biomass. distribution proportion were clum>underground part>branch>leaf.2)Four pairs bamboo buds which located at stem basal were named at first bud, second bud, third bud and fourth bud from bottom to top in sequence, in order to survey reproductive capacity of bamboo buds,bamboo shooting and growth of four pairs bamboo buds were surveied. The result showed that one-year-old mother bamboo had the best reproductive capablity,then decreased quikly at two years old, at three years old, the mother bamboo had had almost lost reproductive capacity. For different bamboo buds locations, the shooting rate and survival rate of bamboo shoots were the second bud>first bud>third bud>fourth bud, furthermore, the first and the second buds were significantly higher than the third and the fourth buds. The comprehensive analysis showed that The shooting rate and the survival rate of first bud at one-year-old mother bamboo in three Sympodial bamboo were 65%,60% respectively ,and secend bud was up to70%,65% respectively.It was manytimes than third and fourth buds.So,the germination ability of the first and the second buds at one-year-old mother bamboo were optimal. Germination age and shooting time of bamboo buds were related with the buds locations, the germination age and shooting time of the first and the second bamboo buds located in middle and lower location were earlier than the third and the fourth bamboo buds. these conclusions could provide scientific basis for stand structure regulation. 3)In order to seek age-structure of three bamboo. thinning experiments of age-structure were arranged.The result showed that shoot-emergence number increased rapidly with increasing thinning emphasize and the survival rate of bamboo shoots,relative growth rate first increase and then decrease. the yield of D.farinosus, B.rigida were up to2271.7,2219.1kg/Mu at C₃ treatment respectively, the yield increase rate being 68.29%,49.97%; the yield of B. pervariabilis×D. daii were up to2014.9 kg/mu at C₂ treatment, the yield increase rate being 19.19%. these conclusions showed that one years mather bamboo should be whole retained,two year mather bamboo could partially hold.4)In order to improve nutrient utilization, use for reference form bud picking.third and fourth buds which have poor shooting and survival rate were resected.The result showed that erasing bamboo buds have no obvious effect to shooting rate,but could increase the survival rate of bamboo shoots,relative growth rate and bamboo yields markedly. yield-increasing effect at erasing third and fourth buds was best. the survival rate of three bamboo shoots increase 6.69%,11.64%,15.06% respectively, relative growth rate increase 5.51%,5.91%,4.73% and the rate of yield-increasing were31.04%,25.59%, 37.87% respectively. These conclusions showed that erasing bamboo buds could increase survival rate, relative growth rate and bamboo yield.5)In order to study comprehensive technology of bamboo pulp forest, L₉(3₄) Orthogonal Design Test of comprehensive technology were arranged.The result of orthogonal test showed that fertilization was an important management measure which could increase survival rate of bamboo shoots,shooting rate and relative growth rate obviously.yield-increasing effect at the level of 1.5kg/clump was best. Hilling which increase bamboo shoots and yield could speeding up bamboo rhizome floating upward,so Hill the bamboo-clump which floating upward seriously. At last, pawing out soil and sunning buds have no obvious effect to bamboo shoot and bamboo growth. So, fertilization could be used in production regularly;Hilling could be considered appropriately;pawing out soil and sunning buds ,which influence can be neglected.