以人为本快速反应高效有序开展抗震救灾工作

2007年6月3日凌晨,云南省普洱市宁洱县境内发生里氏6.4级地震,此次地震震源浅,震级高,破坏力大,造成了普洱市5个县(区)40.3万人受灾,42万多间房屋倒损,其中倒塌9万多间,紧急转移安置灾民18万多人。教育、卫生、公路、通讯、水利、电力、市政等基础设施受损严重。直接经济损失18.99亿元。     

Relationship between (210)Pb(ex) activity and sedimentary organic carbon in sediments of 3 Chinese lakes

This report demonstrates that organic matter was an important factor in lake sediment ²¹⁰Pb_ex dating. Sediment cores from lakes in central and western China with different-trophic levels were collected, and the ²¹⁰Pb_ex activity and total organic carbon (TOC) were measured. The Rock-Eval pyrolysis technique was used to deconvolute TOC into free hydrocarbons (S1), thermally less-stable macromolecular organic matter (S2a), kerogen (S2b), and residual carbon (RC). The results show significant correlations between TOC and ²¹⁰Pb_ex, particularly between S2a and ²¹⁰Pb_ex, in all the sediment cores. This indicated that the algal-derived organic component S2a may play the most important role in controlling the distribution of ²¹⁰Pb_ex. Scavenging by algal-derived organic matter may be the main mechanism. As chronology is the key to the understanding of pollution reconstruction and early diagenesis in sediments, more attention should be paid to the influence of organic matter on ²¹⁰Pb_ex.