阔叶红松林不同大小林隙土壤温度、水分、养分及微生物动态变化

对小兴安岭阔叶红松林不同大小林隙主要土壤性质和微生物数量进行测定,对其动态变化进行比较和分析。结果表明,林隙表层(0-10cm)土壤含水量比郁闭林分高。不同大小林隙土壤月平均温度呈现单峰变化。中林隙有机质平均含量(194.34g/kg)>大林隙(169.47g/kg)>小林隙(143.49g/kg)>郁闭林分(128.61g/kg)。各林隙土壤表层NH4+-N含量季节动态变化趋势基本一致。大林隙中,土壤各月平均总有效氮(铵态氮+硝态氮)含量春季最高,夏季最低。林隙的有效磷含量呈现多峰变化。8月份是速效钾吸收和淋失的高峰期。林隙土壤微生物的数量秋季最多,生长季和雨季较少。不同大小林隙土壤因子的相关分析表明,pH值与有机质、速效钾呈显著负相关,与微生物和有效磷呈显著正相关。有机质与全氮、铵态氮、硝态氮、微生物和速效钾呈现显著或极显著相关。

Dynamic Changes in Soil Temperature,Water Content,Nutrition and Microorganisms of Different Size Gaps in the Mixed Broadleaved Korean Pine Forest

The main soil properties and microorganisms quantity were measured and their dynamic variation were analyzed and compared in different size forest gaps in broad-leaved Pinus koriensis forest of Xiaoxing’an Mountain.Conclusions were as follows: Water content in upper soil layer(0-10 cm) in forest gaps was higher than that in closed forest.The monthly changes in soil temperature showed unimodal curve.Mean soil organic matter decreased in the order of medium gap(194.34 g/kg),large gap(169.47 g/kg),small gap(143.49 g/kg),closed forest(128.61 g/kg).Seasonally dynamic change in NH+4-N in upper soil layer in each gap exhibited basically the same trend.Mean total available nitrogen(NH+4-N+NO-3-N) in large gap was highest in spring and lowest in summer.The available phosphorus content presented multimodal curve.The peaks of absorption and leaching of available potassium in forest gaps occurred in August.Soil microorganic quantities were the highest in August in three gaps,but lower in growing season and rainy season.Correlation analysis indicated that significantly negative correlation existed between pH value and organic matter,available potassium,but significantly positive correlation existed between pH value and microorganisms and available phosphorus.Organic matter was significantly or highly significantly correlated with total nitrogen,ammonium nitrogen,nitrate nitrogen,available phosphorus and available potassium.