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以移栽自兴安落叶松林自然分布区内4个纬度梯度(塔河、松岭、孙吴和带岭)的8年生兴安落叶松林为对象,于移栽3年后(2007年)的春季土壤解冻期,采用氯仿熏蒸浸提法测定了4个纬度梯度(处理)土壤的微生物生物量碳(Cmic)和微生物生物量氮(Nmic)的时间动态.结果表明:在相似基质和相同气候条件下,移栽自4个纬度梯度的兴安落叶松林春季土壤解冻期的Cmic和Nmic平均值差异显著,呈随纬度升高而减少、随土层加深而下降的分布格局.其中塔河、松岭、孙吴和带岭的Cmic平均为554.63、826.41、874.81和1246.18mg·kg-1,而Nmic分别为70.63、96.78、79.76和119.66mg·kg-1.Cmic和Nmic在解冻前达到最大值;解冻初期迅速下降;在冻融交替阶段变化不显著,且维持在较低水平;在解冻末期,来自低纬度的带岭和孙吴的Cmic回升较快.春季冻融期土壤温度和含水量对Cmic和Nmic的影响显著,其影响程度随冻融阶段而变化.土壤微生物生物量与解冻前的土壤温度呈负相关,与整个解冻期间的土壤含水量呈指数关系.
The 8-year-old Larix gmelinii forest, which was transplanted from the natural latitudes of Larix gmelinii forest in Tahe, Songling, Sunwu and Linglin, was used as the target. After 3 years of transplanting (2007) During the thawing period, the temporal dynamics of microbial biomass carbon (Cmic) and microbial biomass nitrogen (Nmic) in four latitudinal gradients (treatments) were determined by chloroform fumigation method.The results showed that under similar conditions and under the same climatic conditions , The average values of Cmic and Nmic in soil thawed during the thawing period of Larix gmelinii forest transplanted from 4 latitudes varied significantly with the decreasing of latitude and decreasing with the deepening of the soil layer.The distribution pattern of Tahe, Songling, The average Cmic values of Sun Wu and Lingling were 554.63, 826.41, 874.81 and 1246.18 mg · kg-1, respectively, while the Nmic values were 70.63, 96.78, 79.76 and 119.66 mg · kg-1, respectively. The initial stage of rapid decline in the freezing and thawing of the transitional phase did not change significantly, and maintained at a low level; at the end of thawing, from low latitudes Ridge and Sun Wu Cmic rebound faster. Spring soil temperature and water content during freezing and thawing Cmic And Nmic significant impact, the extent of its impact with the freezing and thawing Changes in soil microbial biomass and soil temperature before the thaw was negatively correlated exponentially with soil moisture throughout the period of thaw.