Method for estimating buried organic carbon in lake sediment based on water volume

Abstract

The invention discloses a method for estimating buried organic carbon in lake sediment based on water quantity. The method comprises the following steps of: collecting lake sediment samples; testing and analyzing the sediment age, the sedimentation rate, the sediment dry density and the organic carbon content; calculating an organic carbon burial rate of a lake; extracting the lake positive high water level through utilizing satellite altimeter data; rejecting abnormal values, acquiring single-day water levels, and calculating annual average water levels; acquiring a high value, a low value and a mean value of the annual average water level; acquiring autumn cloudless Landsat data of a water level extreme value year, and setting a threshold value according to an MNDWI histogram to extract the water body area of the lake; assuming that the lake is a cone, determining the shape of the lake according to the water body areas of the years with extremely high water level and the years with extremely low water level, and estimating the lake water volume corresponding to the average water level for many years; and converting the area of the isometric cone according to the water quantity, and acquiring the total amount of the organic carbon buried in the lake sediment based on the water volume by combining the sediment age and the organic carbon burying rate.

Description

technical field [0001] The invention relates to a method for estimating buried organic carbon in lake sediments based on water volume, belonging to the field of lake hydrology. [0002] technical background [0003] Lakes are important carbon sinks. In the early days, the role of lakes in the carbon cycle was neglected because lakes accounted for a small area of ​​the earth's land surface (lakes accounted for about 2.8% of the land area). Although carbon dioxide and methane discharged into the atmosphere from inland water bodies such as lakes and reservoirs will become greenhouse gases and are carbon sources, carbon stored in sediments will enter long-term geological cycles and is also a permanent and important carbon sink. Local and regional-scale studies have shown that even though the flux of carbon burial in lake and reservoir sediments is generally smaller than that of carbon emission, it is still an important long-term carbon sink and plays an important role in the reg...

AI Technical Summary

Problems solved by technology

However, due to the lack of data, most of the current researches directly multiply the organic carbon burial rate by the lake area to obtain the total organic carbon burial

while lake area is usually an instantaneous result for a given year, which adds to the uncertainty of the estimates

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