陇中南黄土残塬区表土的孢粉和气孔器特征及相关研究

Characteristics of sporopollen and stomatal apparatus in surface soil from Loess Broken Plateau Area in the Central South of Gansu Province and related research

对陇中南黄土残塬区15个采样点表土中的孢粉和气孔器进行了鉴定,在此基础上,对该区域表土孢粉和气孔器的总体特征及不同植被类型表土的孢粉特征进行了分析,并对各采样点进行了聚类分析,对花粉类型和采样点进行了DCA排序分析。结果表明:该区域表土中的孢粉以木本植物花粉为主(花粉百分含量的均值为71.2%),木本植物与草本植物花粉数量比值的均值为2.5,主要孢粉类型有松属(Pinus Linn.)、云杉属(Picea A.Dietr.)、蒿属(Artemisia Linn.)和水龙骨属(Polypodiodes Ching);气孔器只有柏科(Cupressaceae)、松属和云杉属3个类型。针叶林和森林草原表土中的孢粉能够很好地反映母体植被的群落特征,针阔混交林表土中的孢粉能够较好地反映母体植被的群落特征,灌丛表土中的孢粉基本能够反映母体植被的群落特征,落叶阔叶林表土中的孢粉不能反映母体植被的群落特征。聚类分析结果表明:15个采样点被分成Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ5组,分别包含1至3号、4至9号、10号、11至13号及14和15号采样点,并且,Ⅱ组的采样点进一步分成2个小组,而Ⅲ和Ⅳ组的采样点可聚在一起,说明该区域落叶阔叶林表土的孢粉组成差异较大,林地与灌丛和森林草原表土的孢粉组成差异较大,林地边缘区域表土的孢粉组成受外界孢粉散播干扰明显。DCA排序分析结果表明:花粉类型和采样点沿排序轴分类明显。研究结果显示:在陇中南黄土残塬区,松属、云杉属和蒿属植物花粉具有超代表性,孢粉和气孔器数据相结合能够准确指示该区域母体植物的分布状况,利用孢粉的百分含量可较好地区分该区域的植被类型。

Sporopollen and stomatal apparatus in surface soil of 15 sampling sites from Loess Broken Plateau Area in the Central South of Gansu Province were identified,on the basis,general characteristics of sporopollen and stomatal apparatus in surface soil of this area and sporopollen characteristics in surface soil of different vegetation types were analyzed,and cluster analysis on each sampling site was conducted,DCA ordination analyses on pollen type and sampling site were performed.The results show that sporopollen in surface soil of this area is mainly woody plant pollen(mean of pollen percentage is 71.2%),and mean ratio of pollen number of woody plants to that of herbaceous plants is 2.5,the main sporopollen types are Pinus Linn.,Picea A.Dietr.,Artemisia Linn.,and Polypodiodes Ching;stomatal apparatuses only have 3 types of Cupressaceae,Pinus,and Picea.Sporopollens in surface soil of coniferous forest and forest steppe can nicely reflect the community characteristics of parent vegetation,that of coniferous and broad-leaved mixed forest can do well,and that of shrub can do basically,while that of deciduous broad-leaved forest cannot do.The cluster analysis result shows that 15 sampling sites are divided into 5 groups ofⅠ,Ⅱ,Ⅲ,Ⅳ,andⅤ,which contain Nos.of 1-3,4-9,10,11-13,and 14 and 15 sampling sites,respectively;and sampling sites in groupⅡare further divided into 2 small groups,while those in groupⅢand groupⅣcan be clustered together,indicating that there is a relatively big difference in composition of sporopollen in surface soil of deciduous broad-leaved forest in this area,and there are relatively big differences in composition of sporopollen in surface soil of forest land with shrub and forest steppe,and composition of sporopollen in surface soil of forest land margin area is evidently interfered by external sporopollen spread.The DCA ordination analysis result shows that the classification of pollen type and sampling site are evident along the ordination axes.It is suggested that in Loess Broken Plateau Area in the Central South of Gansu Province,pollens of Pinus,Picea,and Artemisia plants have super-representations,combining data of sporopollen and stomatal apparatus can accurately indicate the distribution status of parent plants in this area,and percentage of sporopollen can be used to distinguish vegetation type in this area.