Research On The Microbialactivity Of Litter Layer And Soil In Snow Cover Korean Pine In Changbai Mountain

Forest soil can keep 0℃under snow for several months in winter, beginning microbial break up nutrition for storage at this time then supply a large number of nourishment for plants at spring. Soil microbial biomass is an important indicator in evaluating land management measures on the impact of the soil quality, most microbial have strong activity and number in the winter, but some microbial activity will be clearly decline in the spring. The increasing trend of soil microbial biomass be achieved by reducing soil organic matter and soil nitrogen within a year from summer to winter. Enzyme mainly from soil microbes, others come from the plants and soil animals. All of the biochemistry responses are catalyzed by enzymes, amylase and cellulose can be characterized the nutrient cycling situation such as soil C and N, soil organic substance can be oxidation by peroxidase, soil urease of soil microbial activity is an effective index. Litter decomposition can made the C,N,P,K and other nutrition in growing season return to the soil and those matter provide sufficient nutrients for plant growth.In this paper, the typical forest ecosystems surface soil and litter of Changbai Mountain were choices, control the temperature and increase induced matter in the laboratory to cultivate the soil. Frozen refrigerator temperature to simulate natural conditions for the menstruate of soil respiration, other temperature settings for comparing the winter under the snow cover with the growing season of soil respiration; number of statistical and identification for soil microorganisms, all carbon and nitrogen analysis; determination of the activity of soil enzyme for study the changes in its months; understanding of soil organic substance and nitrogen changes in months; study the litter on the natural decomposition, observe its decomposition rate; the results are as follows:1) The soil respiration of CO₂ release in Broad—leaved and Korean pine forest: Although the low temperature in winter affecte d soil respiration of CO₂ release, but the soil respiration CO₂ release in the winter have more value, with the temperature stable soil respiration CO₂ release has increased, numerical value in some month is higher than the growth season; It can enhance the ability of soil respiration with adding glucose and glucose + litter; the size of soil respiration CO₂ released to the temperature is 0℃>4℃>-8℃in November and December and 4℃> 0℃> -8℃in January, February, March and April2) Microbial population structure and time dynamics of biomass: After experimentation there are seven advantage of cold—adapted microorganism include three fungi and four bacteria. The number of microbes are high both in winter and summer, in April and May the number started to decline and also low at September, that is the growing season> winter> spring. Through physiological and biochemical tests know that the physical and chemical properties of bacteria under different condition. Microbial biomass carbon and nitrogen are high number under the conditions of low temperature in winter, the change of microbial biomass carbon is winter> summer> autumn >spring when the microbial biomass nitrogen is winter> autumn> summer> spring.3) Activity of soil enzyme changes: All enzyme activity in 0-15 cm layer is higher than 15-20 cm of soil, and the change of 15-20 layer is small. Amylase and cellulose has high activity in low temperature months, this high activity in the growing season is similar. Amylase activity decreased in May and June but has the highest activity in July, August and September, the activity started to decline from October to December; January, February, March the activity increased. The activity of cellulose and starch is similar to the activity of amylase, but the highest activity come in winter; the activity of Urease and catalase is lower in the winter but higher in the growing season, with the increase of temperature, the activity strengthened, the activity of Urine in the summer was significantly higher than that in winter.4) Changes of Organic matter and nitrogen: Soil organic matter has a high number in the winter and before the growing season, nitrogen content rising higher with the increase of temperature, soil organic matter and nitrogen activity in 0-15cm layer are higher than 15-25 cm , organic matter and nitrogen activity has little change in15-25 cm layer.5) Investigate the dynamics of litter decomposition: the maximum decomposition rate of litter is in the winter, the rate is lower in the growing season. In the winter litter covered by snow, snow can keep quantity of heat and the permeability humidity of snow can provide an adaptive temperature for micro-organisms, so there are high number of microorganisms and activity under snow.