Late Holocene pollen and organic walled dinoflagellate cysts analyses of sedimet cores from the Java Sea

The pollen, spore and organic walled dinoflagelletas cyst associations of two marine sediment cores from the Java Sea off the mouths of Jelai River (South Kalimantan) and Solo River (East Java) reflect environment and vegetation changes during the last ca 3500 years in the region. A decline in primary forest taxa (e.g. Agathis, Allophylus, Dacrycarpus, Dacrydium, Dipterocarpaceae, Phyllocladus, and Podocarpus) suggest that the major change in vegetation is caused by the forest canopy opening that can be related to human activity. The successively increase of pollen of pioneer canopy and herb taxa (e.g. Acalypha, Ficus, Macaranga/Mallotus, Trema, Pandanus) indicate the development of a secondary vegetation. In Java these changes started much earlier (ca at 2950 cal yr BP) then in Kalimantan (ca at 910 cal yr BP) and seem to be more severe. Changes in the marine realm, reflected by the dinoflagellate cyst association correspond to changes in vegetation on land. They reflect a gradual change from relatively well ventilated to more hypoxic bottom/pore water conditions in a more eutrophic environment. Near the coast of Java, the shift of the water trophic status took place between ca 820 and 500 cal yrs BP, while near the coast of Kalimantan it occurred as late as at the beginning of the 20th century. We observe an increasing amount of the cyst of Polykrikos schwarzii, cyst of P. kofoidii, Lingulodinium machaerophorum, Nematosphaeropsis labyrinthus and Selenopemphix nephroides at times of secondary vegetation development on land, suggesting that these species react strongly on human induced changes in the marine environment, probably related to increased pollution and eutrophication.

取自加里曼丹南部哲莱河（Jelai River）河口外爪哇海，以及东爪哇梭罗河（Solo River）河口外爪哇海的两处海洋沉积岩芯，其所含的花粉、孢子与有机壁沟鞭藻囊孢（dinoflagellate cyst）组合，反映了该区域过去约3500年以来的环境与植被演变历程。原生森林类群（如贝壳杉属*Agathis*、异木患属*Allophylus*、泪松属*Dacrycarpus*、陆均松属*Dacrydium*、龙脑香科*Dipterocarpaceae*、叶枝杉属*Phyllocladus*以及罗汉松属*Podocarpus*）的丰度下降，表明植被的主要转变源于林冠开放，这一过程与人类活动密切相关。先锋冠层类群与草本类群的花粉丰度持续上升（如铁苋菜属*Acalypha*、榕属*Ficus*、血桐属/野桐属*Macaranga/Mallotus*、山黄麻属*Trema*以及露兜树属*Pandanus*），指示了次生植被的发育过程。爪哇地区的此类转变起始时间远早于加里曼丹（约2950校准年前[cal yr BP]），而加里曼丹的转变起始时间约为910校准年前[cal yr BP]，且爪哇的植被转变程度似乎更为剧烈。以沟鞭藻囊孢组合所反映的海洋环境变化，与陆地植被变化呈现对应关系：此类变化指示了环境从相对富氧的底层/孔隙水条件，逐步向富营养化程度更高的低氧底层/孔隙水条件转变。爪哇近岸海域的水体营养状态转变发生于约820至500校准年前之间，而加里曼丹近岸海域的此类转变直至20世纪初才发生。我们观察到，当陆地次生植被发育时，施瓦茨多丝藻*Polykrikos schwarzii*囊孢、科氏多丝藻*P. kofoidii*、镰状原多甲藻*Lingulodinium machaerophorum*、迷宫拟球藻*Nematosphaeropsis labyrinthus*以及肾形硒甲藻*Selenopemphix nephroides*的丰度持续上升，这表明这些物种对人类活动诱导的海洋环境变化响应强烈，此类变化大概率与污染加剧及富营养化程度升高相关。