Paleoenvironmental information recorded by pollen in B-3GC gravity core in Okinawa Trough  

作　　者：SONG Changqing, SUN Xiangjun & Yoshiki SaitoNational Natural Science Foundation of China, Beijing 100085, China Open Lab of Marine Geology, Tongji University, Shanghai 200039, China Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China Geological Survey of Japan, Higashi 1-1-3, Tsukuba, Ibaraki, 305-8567,Japan 

出　　处：《Chinese Science Bulletin》2001年第11期938-942,共5页

基　　金：the Special Coordination Funds for Promoting Science and Technology of the Science and Technology Agency of Japan and by the National Natural Science Foundation of China (Grant Nos. 49732060 and 49894170).

摘　　要：Based on pollen records in B-3GC gravity core, environmental change since 9500 aBP of Okinawa Trough and its adjacent islands was derived. The result showed that the most time during this period was in a warm temperate climate except in middle Holocene (6800-4400 aBP) that was under subtropical climate control. During 9500-8300 aBP and 3100-2000 aBP periods, it appeared colder and drier than the rest time. The original area of pollen sources surrounding Okinawa Trough was covered by evergreen and deciduous broadleaf forest alternatively with mixed broad-leaf-conifer forest distributed in high mountainous areas. Usually, these three kinds of forests existed at the same time with difference in altitude. Pollen from subtropical and tropical plants increased obviously in about 5000-6000 aBP, reflecting a great lifting of vegetation zone and expansion of evergreen broad-leaf forest in the study area. However, there was a slight descending of plant zone and shrinking of evergreen broadleaf forest duringBased on pollen records in B-3GC gravity core, environmental change since 9500 aBP of Okinawa Trough and its adjacent islands was derived. The result showed that the most time during this period was in a warm temperate climate except in middle Holocene (6800-4400 aBP) that was under subtropical climate control. During 9500-8300 aBP and 3100-2000 aBP periods, it appeared colder and drier than the rest time. The original area of pollen sources surrounding Okinawa Trough was covered by evergreen and deciduous broadleaf forest alternatively with mixed broad-leaf-conifer forest distributed in high mountainous areas. Usually, these three kinds of forests existed at the same time with difference in altitude. Pollen from subtropical and tropical plants increased obviously in about 5000-6000 aBP, reflecting a great lifting of vegetation zone and expansion of evergreen broad-leaf forest in the study area. However, there was a slight descending of plant zone and shrinking of evergreen broadleaf forest during 9500-8300 aBP and 3000-2000 aBP. During the remaining periods vegetation zone was higher than the present but in a limited range.

关 键 词：environmental change HOLOCENE POLLEN OKINAWA Trough. 

分 类 号：P59[天文地球—地球化学]