古温度定量重建的良好代用指标——湖泊沉积摇蚊化石记录研究进展

A POWERFUL INDICATOR FOR QUANTITATIVE RECONSTRUCTION OF PALEOTEMPERATURE ——ADVANCES IN THE STUDY OF SUBFOSSIL CHIRONOMID IN LAKE SEDIMENT

(双翅目)摇蚊科昆虫对环境因子的变化相当敏感,其水生幼虫的头囊能保存于湖相沉积物中,在国际古湖泊和古环境研究中常被用作一种环境替代指标。因为不同种属的摇蚊对环境因子的最适值和耐受范围有较大差异,所以利用湖相沉积物中的摇蚊化石组合面貌的变化可达到古环境的定量重建。在欧洲和北美进行的许多研究已证实摇蚊是古温度的有效指示器,重建夏季温度相对准确可靠,比其它气候变化代用指标有优势,很可能成为国际上古气温重建所使用的首要生物代用指标。截止目前,该领域研究在国内尚未开展,我国湖泊众多,利用摇蚊研究古温度记录潜力巨大。

Chironomidae (Diptera) is sensitive to environmental change and its larvae possesses a chitinized head capsule whichis resistant to decomposition. This kind of invertebrate is usually used as a proxy of paleoenvironmental change. Because different chironomid taxa have different environmental optima and tolerance, and the ecological magnitude of many chironomid species isvery narrow, the change of chironomid composition in lake sediments can be used to reconstruct paleoenvironment. In Europe and North America, many researches have testified that chironomid is a very effective indicator for paleotemperature, especially for the reconstruction of summer temperature. It has some advantages over other proxies used to indicate climatic change and has potential to become the principal biological proxy in quantitative paleotemperature reconstruction. In western countries, the research in this field has developed fast in recent years. In China where there are many lakes located in different temperature zones, however, little progress has been made now in the utilization of chironomids for reconstruction of paleoclimate or paleoenvironment. Obviously, there are great potentials to use fossil chironomid in the Lakes of China as an indicator for paleotemperature.