The Study Of Rotation Age In Larch Plantation

The determining cut age of artificial timber is the key technique in plantation management. A long time, in the production activities, the determining cut age is mainly based on the number mature and technology mature, and the economic factors are relatively few to be considerd. the traditional method of harvesting age is difficult to meet the needs of the scientific management of artificial timber. therefore There is a need from the theory, techniques and methods to conduct research to guide practice. this paper analyze and summarize the relevant research results at home and abroad.the theory, techniques and methods of reasonable artificial timber harvesting age were studied. The mathematical programming is used in plantation. The main conclusion of the study are as follows:1, The baseline age of 30 years is determined in application of sample survey data , the larch plantation site quality is fitted, and the multiple coefficient of determination of various factors are determined in the model. Fitting results show that the function is the best larch plantation sub-index of the status of class-oriented curve model, the model status-class index:SCI=(H|-)*exp((12.51004/A)-(12.51004/30))2, The diameter, volume and age, density is non-linear relationship between index in the same average height stand.After fitting, the larch stand mean diameter, arithmetic mean diameter, volume forecast model are gained. The test results of various models shows that the model's forecast accuracy is more than 91% and pass the F test.3, The diameter distribution of larch forest were fitted in use of Weibull function. the model parameters are acquired in use of the parameter recovery method.4, According to the model, the rotation is calculated in different site conditions, stand density. The purlin timber rotation of Larch is a period of 14-23 years; the pitprop rotation is period of 17-31 years; only a density of 1000 / hm2, status-class index 18, the logs rotation is period of 44 years , the logs rotation of other stands are 50 years upwards.