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在精确AMS14C年代测定的基础上,对采自广西桂林岩溶区西南村的沉积样品进行了孢子、花粉和淡水藻类分析,获取了该地区中全新世以来的植被、气候和沉积环境变化的记录.结果显示,ca.5390~1990 cal a BP研究区周围分布有亚热带常绿落叶阔叶林和少许针叶林,低山丘陵上生长着以常绿栎为主的常绿落叶阔叶林,较高海拔处分布有少量以松为主的针叶林,气候温暖湿润;ca.1990~380 cal a BP植被演替为亚热带常绿落叶阔叶、针叶混交林,气温较前一阶段有所降低,期间存在冷暖干湿变化.ca.5390~3160,ca.1990~1540和ca.1360~750 cal a BP三个阶段剖面所在位置湿生草本植物莎草科花粉和淡水藻类环纹藻含量同步升高,指示研究区内水域面积扩大;ca.3160~1990 cal a BP发育泥炭;而ca.1540~1360与ca.750~380 cal a BP两个阶段莎草科花粉和环纹藻含量下降,说明水域面积有所缩小.ca.750~380 cal a BP,人类活动不断增强,森林植被和沼泽资源遭受破坏,石漠化日益加剧.
On the basis of the accurate AMS14C dating, the spore, pollen and freshwater algae collected from the southwestern village of Karst area in Guilin, Guangxi Province were analyzed, and the records of the changes of vegetation, climate and sedimentary environment in the area since the Holocene were obtained. The results showed that subtropical evergreen deciduous broad-leaved forest and coniferous forest were distributed around ca.5390 ~ 1990 cal a BP. The evergreen and deciduous broad-leaved forest dominated by evergreen oak grew in the hilly region, There was a small amount of coniferous forest dominated by pine at high altitude, and the climate was warm and humid. The succession of vegetation from 1990 to 380 cal BP was subtropical evergreen and deciduous broad-leaved and coniferous mixed forest, Decreased during cold and warm wet and dry changes.ca.5390 ~ 3160, ca.1990 ~ 1540 and ca.1360 ~ 750 cal a BP section of the three stages where the location of the wet plant herbs Cyperaceae and freshwater algae ring algae content The area of water in the study area was expanded; ca.3160 ~ 1990 cal a BP developed peat; while the contents of pollen and ring algae in ca. 1540 ~ 1360 and ca. 750 ~ 380 cal a BP Decline, indicating that the water area has been reduced .ca.750 ~ 380 cal a BP, human activity is not Enhancement, forest and swamp vegetation resources destroyed, increasing desertification.