东北三江平原全新世火演化及其与植被和气候的关系

通过勤得利泥炭剖面碳屑、花粉记录,重建东北三江平原地区全新世火演化与植被变化的历史;研究火演化与植被、气候的关系;探讨人类火活动及其环境效应的信息。三江平原最近9700aB.P.以来,疏林草原植被时期(9200-8500aB.P.)和疏林植被时期(9700-9200aB.P.)对应了暖干气候阶段,碳屑浓度出现峰值,而湿润时期的碳屑浓度均很低。显示在暖干气候阶段,火灾发生的频次高、强度大;湿润或相对湿润阶段。火灾力度相对较小或频次较低。同时,自然植被状况和植物类型同样制约了天然火发生的频次和强度。20世纪50年代三江平原开发与垦荒对火演化和环境产生重要影响。

Fire variations and Relationship among Fire and Vegetation and Climate during Holocene at Sanjiang Plain, Northeast China

The records of charcoal and pollen from peat section at Qindeli, NortheastChina help us to reconstruct the fire variation and the vegetation history in the Holocene at Sanjiang Plain and to study their relationship a-mong fire, vegetation and climate. The reconstruction of fire history also discusses the human activity of fire and the impact on environment. Two peak values of charcoal concentration appeared in the two periods of spares forest and grassland (9 200 -8 500 a B. P. ) and spares forest (9 700 -9 200 a B. P. ) corresponding to two climate epochs of warm-dry and relatively warm-arid respectively. In the wet period the charcoal concentration shows the low values. The frequency and intensity of fire are high in the dry period and low in the wet period. However, the characteristic of vegetation and the types of plant also restrict the frequency and intensity of fire in the Holocene at Sanjiang Plain. In the mean time, the exploitation to Sanjiang Plain influenced the fire variation and environment greatly after the 1950s.