Construction of a carbon budget model of soil ecosystems for measures to prevent the global worming

北海道森林和农用地的年固碳量为10.61 × 10^6 tC，由于化石能源的大量消耗，其年预算排放量为9.09 × 10^6 tC。为达到收支平衡，人口应减少到现有人口的59% （3.34 × 10^6人口），人口密度为40人km^<-1>。2000年和2002年关东八城地区森林地表co2排放量分别为：落叶栎林501 mgCO_2 m^<-2> h^<-1>和常绿针叶松319 mgCO_2 m^<-2> h^<-1>。通过室内碳矿化试验估算了不同气候、母质和植被条件下的森林CO_2通量不仅受土壤温度的影响，还受树木季节生理状态的影响。牧场果园草根系中，强酸性和强酸性非磷磷化合物最多，低腐殖质磷磷化合物最少。在整地时施用缓释肥料显著降低了果园草地最上层根系的积累量，而常规肥料则在整地时分步施用。经估算，水田耕层渗透到底土的CO_2通量约占耕层总碳含量的几个百分点，渗透到底土的CO_2在汛期被暂时保留。采用一种改进的测定土壤吸附碳酸盐离子的方法，在4% CO_2气氛中改变pH条件，对邻苯二酚进行了测定。吸附量随pH值的增加而增加，但在pH值为7时吸附量最大。施用有机物质（酵母浸出物）后co2排放量依次为冲积土<洪积土<水稻土<安藤土。冲积土微生物群落对碳水化合物代谢最少，而安藤土壤微生物群落对长链碳质有机质保持较高的分解活性，导致安藤土壤长期分解有机质最多。少

The annual carbon fixation in forests and agricultural lands in Hokkaido was 10.61 × 10^6 tC and the annual budget was 9.09 × 10^6 tC emission due to the large consumption of fossil energy. And for the balanced budget, the population should decrease to 59 % of the present population (3.34 × 10^6 population) and the population density be 40 persons km^<-1>. The CO_2 emission from the forest floors in Hachijoji, Kanto District was 501 mgCO_2 m^<-2> h^<-1> for a deciduous oak (Quercus serrata) forest and 319 mgCO_2 m^<-2> h^<-1> for an evergreen needle-leaved Japanese cypress, respectively, during 2000 and 2002. CO_2 fluxes from the forests under different conditions of climate, parent materials, and vegetation were known to be influenced by not only soil temperature but also seasonal physiological status of forest trees, which was estimated from the laboratory experiment of carbon mineralization.Root system of orchard grass in pasture was concentrated in the uppermost layer most in stron … More gly-acidic non-allophanic Andisols, and least in low-humic allophonic Andisols, respectively. The application of slowly-released fertilizers at the time of land preparation significantly decreased the accumulation of root system of orchard grass in the uppermost layer in comparison with split application of conventional fertilizers.CO_2 flux to the subsoil by water percolation was estimated to amount to several percents of total carbon content in the plow layer of a paddy field, and the percolated CO_2 to the subsoil was temporally retained during the flooding period.A improved method for determining carbonate ions adsorbed to soils was applied to allophonic Andisols under the 4 % CO_2 atmosphere changing the pH condition. The amount of adsorption increased with the increase in pH without showing the adsorption maximum near pH 7. The CO_2 emission after the application of organic material (yeast extract) increased in the order of alluvial soil < diluvial soil < paddy soil < Ando soil. The microbial community in the alluvial soil metabolized carbohydrate fractions least, and that in the Ando soil maintained the high decomposing activity to long-chain carbonaceous organic materials, resulting in the Ando soil decomposing organic matter most in the long-term. Less