Use of flood chronology for detailed environmental analysis: a case study of Lake Kizaki in the northern Japanese Alps, central Japan

作者：Ito Takuma^*; Iwamoto Haruka; Kamiya Koichi; Fukushima Takehiko; Kumon Fujio

来源：Environmental Earth Sciences, 2010, 60(8): 1607-1618.

DOI：10.1007/s12665-009-0295-y

• Element analysis
• Flood chronology
• Grain size
• Hyperpycnite
• Lake Kizaki

This paper presents a study of the usefulness of flood layers as a time marker in sediments and a report of a case study of Lake Kizaki in central Japan. A flood layer can be identified as a layer having a higher density, coarser grain size, lower TN content, and higher C/N ratio than those of the upper and lower horizons. It can also be characterized by a hyperpycnal sequence composed of a basal coarsening-upward unit and a top fining-upward unit. When flood layers can be correlated with heavy rains in meteorological records, detailed age markers are well established in the sediment. Five flood layers were identified in the surface sediment of Lake Kizaki, and they could be attributed to the historical heavy rainfalls that took place on July 12, 1995; September 28, 1983; August 25, 1974; September 26, 1959; and September 1, 1949 under the constraint of an age model. A precise age model is essential to clarify the environmental changes such as the pollutant history in detail.

• 出版日期2010-6