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宁夏南部海原剖面12.5-7.2 kaBP期间的地球化学元素含量与粒度组成的环境指示意义显著,主要表现为冷干气候条件下植被稀疏,上游及坡面植被水土保持能力低造成粗颗粒物质含量较多,易溶元素如Na氧化物较多被淋失,难溶解的Si、Al、Fe氧化物相对富集;暖湿气候条件下植被发育良好,剖面沉积的细颗粒物质含量较多,土壤中Na元素不易淋失,Si、Al、Fe含量相对减少。但也注意到在温暖湿润环境下,元素活动性相近K2O与Na2O含量出现相反的变化,这可能主要是生物地球化学循化的作用,即植物对钾的吸附作用强于对钠的吸收导致的。
The environmental indicators of geochemical element content and grain size composition in the Haiyuan section of southern Ningxia during 12.5-7.2 kaBP are significant, mainly due to the sparse vegetation in cold and dry climates and the coarse particulate matter content caused by the low soil and water conservation capacity in the upper reaches and slope vegetation , Soluble elements such as Na oxide are more leached, insoluble Si, Al, Fe oxides are relatively enriched; under warm and humid climates well-developed vegetation, the profile of the deposition of more fine particulate matter content in soil Na Element is not easy to leaching, Si, Al, Fe relative reduction. However, it is also noticed that there is an opposite change in K2O and Na2O contents in warm and humid environments, which may be mainly the result of biogeochemical cyclization. That is, the adsorption of potassium by plants is stronger than that of sodium absorption .