【摘要】 综述了用分子地层学方法反演河口缺氧及富营养化发生与发展的研究进展,对可追溯缺氧发生的时间及变化趋势、表征人类活动对缺氧的影响的表征的参数的研究进展进行了分析。研究表明:美国河口缺氧事件的发生可追溯到上世纪中期,自70年代起也呈愈演愈烈的发展趋势。沿海人口的增加及人类活动的加剧导致了营养物质输入的增加,再加上全球变暖的趋势,河口区域缺氧将朝更加严重的方向发展,为此需要采取必要措施,通过减少营养物质尤其是硝酸盐的输入来减缓缺氧。更多还原

【Abstract】 The semi-close Chesapeake Bay and the open Gulf of Mexico were selected as the typical and more severe seasonal hypoxia estuaries to be studied.Here we present a review on the history of the hypoxia and the eutrophication in the last several decadal years according to the stratigraphic records from sediment cores.The main hypoxia characteristic indicators in the sediment included sedimental rate,benthic foraminifers,glauconite and sediment coarse fraction,biogenic silica,total organic carbon(TOC),sulfur speciation,biological markers(fatty acid,pigment,et al),stable carbon and nitrogen isotope.The scientific evidence showed that the hypoxia in U.S.A.estuaries began by approximately mid～1950s and intensified since the 1970s.The more nutrient inputs as the consequence of increasing coastal population and anthropogenic influence,and the global warmer climate would strengthen more severe hypoxia.To reduce,mitigate and control hypoxia in the estuaries,the management policy and actions on decreasing the inputs of nutrient,especially the nitrate loads are necessary.更多还原