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Sediment cores from desert lakes serve as good records of the frequency and intensity of sandstorms in his- tory. By multi-proxy analysis of grain-size, magnetic suscep- tibility, TOC and Rb/Sr ratio, the paleosandstorm character- istics and lake evolution history in Yulin Area for the past 80 years. are discussed in this article. It is revealed that Hong- jiannao Lake formed in about 1928 A.D. and in its initial stage sandstorms were prevalent with three extremes taking place in 1936 A.D., 1939 A.D. and 1941 A.D.. During the ex- pansion period of 1952―1960 A.D., inflow waters to the lake increased sharply and a lot more weathered materials were carried into the lake. The frequency and intensity of sand- storms have reduced a lot since 1960s and the “double peaks” feature of the grain-size frequency curve has changed into the “single peak” feature. Study on the catchment ecol- ogy of the lake shows that the occurrence of sandstorms has been effectively restrained by the forest plantation and water and soil conservation.
Sediment cores from desert lakes serve as good records of the frequency and intensity of sandstorms in his- tory. By multi-proxy analysis of grain-size, magnetic suscep- tibility, TOC and Rb / Sr ratio, the paleosandstorm character- istics and lake are discussed in this article. It is revealed that Hong- jiannao Lake formed in about 1928 AD and in its initial stage sandstorms were prevalent with three extremes taking place in 1936 AD, 1939 AD and 1941 AD. During the exponential period of 1952-1960 AD, inflow waters to the lake increased sharply and a lot more weathered materials were carried into the lake. The frequency and intensity of sand-storms have reduced a lot since 1960s and the “Double peaks” feature of the grain-size frequency curve has changed into the “single peak” feature. Study on the catchment ecol- ogy of the lake shows that the occurrence of sandstorms has been effectively restrained by the fores t plantation and water and soil conservation.