Research On Recovery Effect Of Different Forest Types Of Burned Area In Northern Slope Great Xing’an Mountains

Research on Pinus sylvestris var.mongolica plantation Larix gmelini plantation Betula platyphlla natural forest Pobulus davidiana natural forest in Great Xing’an Mountains which in serious burned occurred in May6,1987. The serious burned aera occurred in2009as the control (hereinafter referred to as the control plots). Litter and soil water holding capacity, soil chemical properties, vegetation diversity of the four forest stands were studied, And assess the restoration effects by using Analytic Hierarchy Process (AHP). Results showed that,(1) The litter tickness of the four forest stand varied from2.3cm to6.2cm. The litter storage of them varied from8.65t·hm-2to37.84t·hm-2, The maximum water-holding capacity of litter had the same order with the storage of litter. It was Larix gmelini plantation> Pinus sylvestris var.mongolica plantation> Betula platyphlla natural forest> Pobulus davidiana natural forest, The soil mechanical composition of the four forest stands are quite different. Compared with the the control plots, we found the content of the soil sand (0.05-2mm) was increased, the content of soil silt particle (0.002-0.05mm) was decreased, the content of soil clay (<0.002mm) as following Larix gmelini plantation and Betula platyphlla natural forest were increased, but Pinus sylvestris var.mongolica plantation and Pobulus davidiana natural forest were decreased. The order of soil bulk density was Pinus sylvestris var.mongolica plantation> Pobulus davidiana natural forest> the control plots> Larix gmelini plantation> Betula platyphlla natural forest. The total porosity soil had the same order with the maximum water-holding capacity of soil. The maximum water-holding capacity of soil was in the order that Betula platyphlla natural forest was665.9t·hm-2, the control plots was615.88t·hm-2、Larix gmelini plantation was597.5t·hm-2, Pobulus davidiana natural forest was559.5t·hm-2, Pinus sylvestris var.mongolica plantation was514.6t·hm-2. There different effects in water-holding capacity of the soil in four forest stands after fire. The order of the maximum water storage of the four forest types were Larix gmelini plantation (721.28t·hm-2)> Betula platyphlla natural forest (715.8t·hm-2)> Pobulus davidiana natural forest (598.1t·hm-2)> Pinus sylvestris var.mongolica plantation (573.35t·hm-2).(2) The soil pH value of four forest stands was Pinus sylvestris var.mongolica plantation> Pobulus davidiana natural forest> Larix gmelini plantation> Betula platyphlla natural forest. Soil organic matter, total nitrogen, hydrolyzed nitrogen, total phosphorus, available phosphorus of four forest types had varying degrees of difference, Compared with the control plots, Soil organic matter, total nitrogen, hydrolyzable nitrogen, total phosphorus and available phosphorus of Larix gmelini plantation, Betula platyphlla natural forest and Pobulus davidiana natural forest increased to varying degree, but the above indices of Pinus sylvestris var. mongolica plantation were observed to decrease on the contrary. Compared with the control plots, Only the soil ammonium of Betula platyphlla natural forest was increased; The soil nitrate nitrogen of Betula platyphlla natural forest was decreased than the serious burned aera occurred in2009,but the other three stands were increased than that, Compared with the control plots, Soil total potassium of four forest stands were all increased, Soil available potassium of four forest stands were all decreased.(3) In the four forest stand, The plant species diversity of Pinus sylvestris var. mongolica plantation was the highest, followed by Larix gmelini plantation, Pobulus davidiana natural forest, Betula platyphlla natural forest. The diversity of coniferous forest was better than broadleaf forest.(4) We evaluation system to establish the effects of different forest types in Great Xing’an Mountains which in serious burned occurred in1987after vegetation restoration by using Analytic Hierarchy Process (AHP), The result show that, The recovery effect of Larix gmelini plantation was the best, and then followed by was Betula platyphlla natural forest and Pinus sylvestris var. mongolica plantation, The recovery effect of Pobulus davidiana natural forest was the worst.