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Variation in aeolian environments recorded by the particle size distribution of lacustrine sediments in Ebinur Lake, northwest China.

Ma L, Wu J, Abuduwaili J - Springerplus (2016)

Bottom Line: Compared with the grain-size distributions of natural dust samples, the results showed that the coarser particle size fraction of lake sediments was mainly derived from the sediments that had experienced aeolian transport to the drainage surface, and the finer sediments came from hydraulic inputs.During the last 150 years, strong intensity aeolian transportation occurred during three periods, 1915-1935, 1965-1975 and since the beginning of the 2000s.Since 1950s, the climate controlled the foundation of aeolian dust transport, and the aeolian dust transport won't be increased under the humid climate.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011 China.

ABSTRACT
Particle size analysis of lacustrine core sediments and atmospheric natural dust were conducted in the drainage area of Ebinur Lake in arid northwest China. Using a combination of (137)Cs and (210)Pb dating, a continuous record of aeolian transportation to the lake sediments and related factors over about the past 150 years was analyzed. Factor analysis revealed the particle-size distributions of riverine and aeolian sediments composed of the terrigenous materials of the lake deposits. Compared with the grain-size distributions of natural dust samples, the results showed that the coarser particle size fraction of lake sediments was mainly derived from the sediments that had experienced aeolian transport to the drainage surface, and the finer sediments came from hydraulic inputs. Then, the method of variations in particle-size standard deviation was used to extract the grain size intervals with the highest variability along a sedimentary sequence. The coarser grain-size populations dominated the variation patterns of the sedimentary sequence. During the last 150 years, strong intensity aeolian transportation occurred during three periods, 1915-1935, 1965-1975 and since the beginning of the 2000s. The climate was dry around 1910s-1930s in this region associated with the appropriate dynamic condition, which provided the enhanced source materials and wind power for the aeolian dust transport. Since 1950s, the climate controlled the foundation of aeolian dust transport, and the aeolian dust transport won't be increased under the humid climate.

No MeSH data available.


Related in: MedlinePlus

The specific activity of 137Cs, total 210Pb and 226Ra versus depth in sediment cores of Ebinur Lake (a) and the related particle size distribution of the sediment cores (b)
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Fig2: The specific activity of 137Cs, total 210Pb and 226Ra versus depth in sediment cores of Ebinur Lake (a) and the related particle size distribution of the sediment cores (b)

Mentions: Figure 2a shows the distribution of 210Pb and 137Cs activities. The unsupported 210Pb activity (210Pbex, 210Pbex = total 210Pb − 226Ra). The 210Pbex decreased from 250 Bq/kg at surface to zero at nearly 49 cm (Fig. 2a). A constant rate of supply model was used to calculate the date for each core sample (Appleby 2001). The beginning of 137Cs activity was appointed 1954 and the peak value was the 1963 fallout maximum from atmospheric testing of nuclear weapons (Pennington et al. 1973), which was consistent with the 210Pb chronology. Figure 2b provides a plot of the sedimentary data versus geologic age.Fig. 2


Variation in aeolian environments recorded by the particle size distribution of lacustrine sediments in Ebinur Lake, northwest China.

Ma L, Wu J, Abuduwaili J - Springerplus (2016)

The specific activity of 137Cs, total 210Pb and 226Ra versus depth in sediment cores of Ebinur Lake (a) and the related particle size distribution of the sediment cores (b)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4837753&req=5

Fig2: The specific activity of 137Cs, total 210Pb and 226Ra versus depth in sediment cores of Ebinur Lake (a) and the related particle size distribution of the sediment cores (b)
Mentions: Figure 2a shows the distribution of 210Pb and 137Cs activities. The unsupported 210Pb activity (210Pbex, 210Pbex = total 210Pb − 226Ra). The 210Pbex decreased from 250 Bq/kg at surface to zero at nearly 49 cm (Fig. 2a). A constant rate of supply model was used to calculate the date for each core sample (Appleby 2001). The beginning of 137Cs activity was appointed 1954 and the peak value was the 1963 fallout maximum from atmospheric testing of nuclear weapons (Pennington et al. 1973), which was consistent with the 210Pb chronology. Figure 2b provides a plot of the sedimentary data versus geologic age.Fig. 2

Bottom Line: Compared with the grain-size distributions of natural dust samples, the results showed that the coarser particle size fraction of lake sediments was mainly derived from the sediments that had experienced aeolian transport to the drainage surface, and the finer sediments came from hydraulic inputs.During the last 150 years, strong intensity aeolian transportation occurred during three periods, 1915-1935, 1965-1975 and since the beginning of the 2000s.Since 1950s, the climate controlled the foundation of aeolian dust transport, and the aeolian dust transport won't be increased under the humid climate.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011 China.

ABSTRACT
Particle size analysis of lacustrine core sediments and atmospheric natural dust were conducted in the drainage area of Ebinur Lake in arid northwest China. Using a combination of (137)Cs and (210)Pb dating, a continuous record of aeolian transportation to the lake sediments and related factors over about the past 150 years was analyzed. Factor analysis revealed the particle-size distributions of riverine and aeolian sediments composed of the terrigenous materials of the lake deposits. Compared with the grain-size distributions of natural dust samples, the results showed that the coarser particle size fraction of lake sediments was mainly derived from the sediments that had experienced aeolian transport to the drainage surface, and the finer sediments came from hydraulic inputs. Then, the method of variations in particle-size standard deviation was used to extract the grain size intervals with the highest variability along a sedimentary sequence. The coarser grain-size populations dominated the variation patterns of the sedimentary sequence. During the last 150 years, strong intensity aeolian transportation occurred during three periods, 1915-1935, 1965-1975 and since the beginning of the 2000s. The climate was dry around 1910s-1930s in this region associated with the appropriate dynamic condition, which provided the enhanced source materials and wind power for the aeolian dust transport. Since 1950s, the climate controlled the foundation of aeolian dust transport, and the aeolian dust transport won't be increased under the humid climate.

No MeSH data available.


Related in: MedlinePlus