Research The Diametric Structure Of Forest Stands And The Growth Process Of Larix Gmelinii At Daxing’ Anling In Inn Mongolia

Using the applicable Linear equation、Logarithmic equation、Reciprocal equation、 Secondary equation、Cubic equation, to fit the relative cumulative percentage of Larix Gmelinii. The result has showed that:no matter artificial forest or natural forest, the best effect is Cubic equation in the five equations. The determination of function R2is almost above0.970, and more than67.5%to reach0.990.Use normal distribution and Weibull distribution to fit diametric structure of artificial forest and natural forest. Making the theory and the actual tree’s number in two distributions do the X2test and finding their acceptable rate. The result has showed that:no matter artificial forest or natural forest, the acceptable rate of Weibull distribution is significantly higher than the acceptable rate of normal distribution in the north、central、 south of Daxing’anling in Inn Mongolia. Especially the natural forest in the north, the acceptable rate of Weibull distribution is2times than normal distribution. Even the natural forest in the centre which acceptable rate is the most approaching, Weibull distribution is13percentage points higher than normal distribution.Use the eight kinds of growth equations to fit the diametric growth process of Larix Gmelinii. The result has showed that:Korf model is the best equation to fit Genhe Forestry、Tulihe Forestry in the central of Daxing’anling and the Southern Region of Daxing’anling, but the best equations to fit other region in central and the Northern Region of Daxing’anling are constituted by three equations:Richards model、Korf model、Correct Weibull model. And, whether it is in the north、central、south of Daxing’anling as long as Larix Gmelinii in the downhill the best model is Korf equation. When the optimum equations divided by density, it can be drawn that:if the density reaches10,000plants/hm2in the north of Daxing’anling, the best model to fit diametric growth process of Larix Gmelinii is Korf equation.When fitting the growth process of tree’s height, we can see that:Richards model is the best equation to fit Genhe Forestry、Tulihe Forestry in the central of Daxing’anling and the Southern Region of Daxing’anling, and the acceptable rate is95%、92%、93%. The best equations to fit other region in central and the Northern Region of Daxing’anling are constituted by three equations:Richards model、Korf model、Correct Weibull model. And, whether it is in the north、central、south of Daxing’anling as long as Larix Gmelinii in the downhill the best model is Richards equation. When the optimum equations divided by density, it can be drawn that:if the density reaches5000～10,000or10,000plants/hm2in the north of Daxing’anling, the best model to fit diametric growth process of Larix Gmelinii is Richards equation.When fitting the growth process of volume, finding has showed significantly different from the diametric and tree’s height process. That is whether Larix Gmelinii in the north、 central、south of Daxing’anling in Inn Mongolia the best model is Correct Weibull equation, and which is significantly better than the other seven equations.