Research On Community Structure And Carbon Accumulation Of Moso Bamboo Forest

Global climate change has inspired scientific and political communities to have an increasing interest in the study of carbon storage and carbon balance. Forest ecosystems are major reserves for terrestrial carbon, and they play an important role in alleviating atmospheric CO2increase and associated carbon balance. Moso bamboo(Phyllostachys pubescens) is not only the major income of local farmers but also other widespread utilization. Bamboo is characterized by fast growth speed, can harvest every other year, and sustainable continuous use. Meanwhile, because of the special asexual reproduction, a large number of new shoots grow each year and extend into the surrounding area. Therefore, bamboo forest has a huge CO2fixation capacity and plays very important role in balancing of atmospheric CO2. In this study, combining the field research with experiements, we investigated the physical characteristics of forest communities, the dominant species important values, and species diversity among bamboo forest, pine forest, broad-leaved forest, and mixed coniferous and broad-leaved forest. We analyzed the effect of degree of bamboo density on bamboo population structure, biomass, and the carbon density. The carbon accumulation rules during its fast growth are also studied. The mojar conclusions are as follows:1. The results from Physical characteristics of different forest communities, the dominant species importance value, and species diversity indicated that broad-leaved forest and mixed coniferous and broad-leaved forest have higher evenness, whereas the pine forest and bamboo forest have lower evenness and instable community because of the larger randomness of species distribution. Moverover, in tree layer, Masson pine and Castanopsis populations account for a large proportion, with an important value of55.75%and28.06%, respectively, in shrub layer, Loropetalum and Picca neoveitchii show a greater advantage.2. The unit biomass of Moso bamboo forest increased with the the increase of bamboo density, showing an upward trend, while an opposite trend was observed in biomass of per plant, average diameter and average height as well. The average of unit bamboo forest is66.82t·hm-2, with a carbon concentration of33.89t·hm2, and the biomass of bamboo trunk part from defferent parts is up to56.39%of the total biomass. In higher bamboo density, e.g.3825plants·hm-2, the unit bamboo could up to75.02t·htm-2, and the average biomass of per plant is19.45kg, with a carbon concentration of38.07t·hm-2, this is an ideal type of carbon sinks business of the bamboo forest.3. The average shoot elongation rate and biomass accumulation rate were about17cm d-1and96g d-1respectively. The carbon content increased progressively with the growth stage at all three parts, while opposite was found for N, P, K, Ca, and Mg content. However, the decline rates of macronutrients were differed among different parts:with middle and lower parts declined greatly after shoot emergence and upper part declined significantly only after first shell detached. Furthermore, the fixed carbon was partitioned into cell wall hemicellulose and cellulose to meet the demand of fast cell elongation. These results indicated that the fast growth of bamboo trunk is related to the extraordinary ability to assimilate carbon but not consistently related with mineral nutritents absorption.