Spatial-temporal Analysis And Prediction Of Forest Above-ground Biomass In Jingouling Forest Farm

Forest ecosystem is the main body of terrestrial ecosystem and exerts huge effect in maintaining global carbon balance and mitigating global warming. Forest biomass is the base of evaluating carbon cycling contribution, so studying its regularity of distribution and dynamic change has a significant meaning for us to understand global carbon balance. Jingouling forest farm is located in Northeast China which ranks among top ones of the list of Chinese carbon density storage areas. The change of forest biomass carbon in this place brings many aspects of ecosystem benefits and needs a deeper study. The inventory data of 1987,1997 and 2007 , combined with forest biomass models and GIS was used to analyze the biomass of the temporal and spatial change in Jingouling farm. Finally the biomass temporal and spatial system was developed with GIS secondary development.Forest biomass storage in Jingouling forest farm of 1987,1997,2007 are respectively 1365484.43t,1552527.21t,1614042.32t.Biomass density are respectively 86.20 t/ hm2,97.31 t/ hm2,100.59 t/ hm2.The ratio of mixed broadleaf-conifer forest, conifer mixed forest, broadleaf mixed forest, Larch forest , other forest types is 5:2:1:1:1.As the time goes on ,the ratio of biomass of Abies nephrolepis forest, Larch forest, mixed broadleaf-conifer forest, conifer mixed forest are decreasing, instead broadleaf mixed forest and other precious tree species such as Pinus koraiensis forest , Picea jazoensis forest are increasing. The ratio of biomass of nature forest to biomass of plantation in last 20 years is 9:1. The trend of biomass growth rate in nature forest is decreasing, instead that plantation has an increasing biomass growth trend as the time moves on. The undesirable phenomenon of the proportion of age structure that the proportion of half-mature forest is larger than mature forest is better as time goes on. Commercial forest is a forest type which has the biggest biomass proportion in all kinds of forest categories and it becomes smaller as the time goes on and the biomass proportions of other forest categories are increasing. Unlike the distribution of biomass density at 100-150 t/ hm2 and 150-200 t/ hm2 ,the distribution of biomass density at 0-50t/ hm2 and 200-400 t/ hm2 shows a regulation show a certain regularity. The aboveground biomass is increasing as the increase of altitude until which reaches 701-850m, where owns the biggest biomass value, after different slope aspect is not so far different from each other. The biomass value of each slope gradient is arranged from high to low : slight slope, ramp, flat slope, abrupt slope .Through test, Grey system prediction and Markov prediction model are respectively suitable for biomass density prediction of different forest type and area prediction. Forest area, above ground biomass, biomass density of Jingouling forest farm are respectively 16065.79 hm2, 1699981.54t, 105.81 t/ hm2.