| The rise of the carbon dioxide’s volume fraction as the main driving force of global warming, has gained widely attention. The vegetation carbon storage played the key factor for studying on forest ecosystem absorb and release the carbon to atmosphere. Therefore, the research information on the vegetation carbon storage and its distribution is of vast importance to evaluate the carbon dioxide source and sink function of regional forest.Based on the plot survey date of forest resource of Haxi Forest in 2000, this paper adopted the method of the Variable Biomass Expansion Factor to calculate the biomass, then multiply by internal conversion coefficient(0.5) to get the total amount of carbon storage, and evaluated the carbon storage from the main type of forest, forest ages, crown density and so on. At the same time, applying the GIS, with the help of forest map and Digital Terrain Model data, the overall spatial distribution feature of the arbor forest carbon storage, and the spatial distribution feature along with the elevation, slope and aspect were studied. At last, through GIS and Geo-statistical Analysis, the forest carbon density of spatial distribution and spatial variable under different scales were studied to provide a science basis for sustainable management. The main conclusions of this study are as follows.1. The total amount of biomass and the carbon storage is 125.40×104t and 62.70×104t in forest region of Haxi in 2000. The biomass of arbor forest occupy a large proportion in Haxi Forest Protection Station, the size order of main type of arbor forest is Picea crassifolia, Sabina praewalskii, Betula, mixed broadleaf-conifer forest, Populus and Coniferous forest. The size order of the different group of main arbor forest is immature timber, near-mature forest, ripe-wood, sapling forest, over-mature forest. The result showed the vegetation carbon storage in study area mainly distributed in immature timber, near-mature forest and ripe-wood. Moreover, the trees in the stand of study area main arbor forest is based on centre crown density(0.4-0.6), and in its components structure the amount of carbon storage in Picea crassifolia is obviously high. The second in the stand is high crown density(above 0.7). And the low crown density(0.2-0.3) is less.2. The characteristic of the carbon storage of the main arbor forest in study area has a significant spatial distribution. The higher biomass amount types such as Picea crassifolia, Coniferous forest and mixed broadleaf-conifer forest, mainly distributed in southeast, northeast and central regions. And with high population density in shallow mountain valleys of eastern, there has a relatively small carbon storage amount. And in the arid, semi-arid area, any vegetation is hardly distributed.The type of arbor forest in research area is main distributed 2100-3900 m. At this range of altitude, the area and the carbon storage of arbor forest performance the increases with the rising of altitude, at the range of altitude 2700-3300 m, it reached the largest, then decreased. The six type of arbor forest are mainly distributed at slope grade 2and 3 that is gentle slope and slope. And there is a larger area and higher carbon storage at slope grade 2, which is showed gentle slope is suit for these type arbor forest. Apart from the Coniferous forest is not distributed at the slope grade 4, the rest are distributed at each slope. Summarizing results, the order of area is northeast, east, northwest, southeast, south, west, north and southwest, and the order of carbon storage is southeast, northeast, east, northwest, west, south, north and southwest.3. By the Log conversion, the data of carbon density under the default precision and different scales obey the normal distribution and then fit the model of semivariable function. Using the statistical analysis module, the optimal models of semivariable function under the default precision and the scales of 30×30m, 300×300m, 600×600m, 900×900m, 1200×1200mand 1500 × 1500 m were Spherical, Gaussian, Spherical, Gaussian, Gaussian and Exponential models. All of the models were fitted well, which could reflect the characteristics of the spatial variation of carbon density.By the variation parameter of the optimal carbon density models, it showed that the rest of the values of C0/C0+C of optimal models were got at the range of 0.2-0.5 except for the scale of 1500×1500m, and the spatial heterogeneity variation were significant. The values of C0/C0+C of optimal models under different scales were smaller, and the values of C/C0+C of optimal models were larger, it showed that the spatial heterogeneity caused by the autocorrelation is higher, the degree of space variation caused by random part is smaller. It turned out that the spatial variation of carbon density is given priority to structure and the random factor such as human disturbance has a less influence on variables. Compared the carbon density variation parameter values under different scales, the precision of 30×30mis relatively close to the default value. |
PDF Full Text Request