洪湖人类活动的沉积物记录

对洪湖150cm长的沉积物样芯进行了TOC、TN、TP、Ca、硫化物测试和AMS定年,在此基础上对洪湖地区人类活动的湖泊沉积响应进行了讨论.TOC和TN的含量呈现相似的变化规律,它们在样芯顶部和底部都出现显著峰值,而中部变化平坦,表示1500年来洪湖环境变演的三个显著不同的阶段;TP从过去到现在总体呈上升的趋势,但上升的幅度不大,这与磷在沉积物中复杂的循环机制有关;Ca的剖面变化显示为底部含量高上部低,其变化情况较复杂;硫化物在顶部15cm的含量比背景值略高,可能指示了上个世纪人类对铁矿和矿物燃料开采强度的增大.

Records of Human Activities in Sediments from Honghu Lake

Basing on the measurements for contents of TOC, TN, TP, Calcium and sulfide and AMS dating of sediment from Honghu Lake, we discussed the response of human activities in the lake sediment. The variations of TOC, TN are agreed with each other. They all appear as a remarkable peak value both on the top and bottom of the core, while flat in the midst. This indicates that the environmental change history of Honghu Lake can be divided into three distinct stages in recent 1500 a. TP generally ascend from past to present, but the extent of rise is not remarkable. This can be related to its complicated cycling mechanism in sediment. The profile of Calcium shows higher in the bottom lower in the top, its variation is complicated. The contents of sulfide on the top 15 cm is higher than the background, this possibly indicates the increase of mining intensity of iron ore and fossil fuel in the last century.