Modern Pollen Assemblages of the Forest Communities and Their Relationships with Vegetation and Climate in Northern China
中国北方森林群落现代花粉与植被和气候的关系

In this paper,53 pollen traps and surface samples were collected in order to detect the characteristics of pollen assemblages and their relationships with vegetation and climate in 16 forest communities located in 10 mountains in northern China.The results show that 72% of the pollen taxa(80 taxa) are the same between the traps and the surface samples.The dominant taxa in the plant communities are consistent with the main pollen taxa in the pollen assemblages at the same sites.In Pinus plant communities,both Pinus pollen influxes and concentrations are higher,indicating its higher pollen product and good pollen preservation ability.In Picea or Abies plant communities,Picea or Abies have lower pollen influx but high concentrations,suggesting their low pollen productivities but good pollen preservation abilities.In Betula or Quercus plant communities,Betula or Quercus have higher pollen influx but low concentrations,revealing their high pollen productivities but poor pollen preservation abilities.The study of the relationships between pollen and vegetation with discriminant analysis shows that pollen assemblages from both trap and surface samples can reflect the characters of different communities and distinguish different ecological areas,but the surface samples reflect the dominant components of communities much better than the traps.The study on the correlations between pollen assemblages and climate with DCCA reveals that significant correlations exist between pollen assemblages and mean temperature of the coldest month(R = 0.84 for trap samples,R = 0.72 for surface samples),and annual mean precipitation as well(R = 0.73 for trap samples,R = 0.71 for surface samples).