Migration and Enrichment of Main Elements in Typical Earth-cumuli-Orthic Anthrosols and Its Significance

Distribution characteristics of elements in soil reflect the result of pedogenic process under the integrated impact of a number of natural and anthropogenic factors.Two typical profiles of Earth-cumuli-Orthic Anthrosols were collected on the third terrace of the Weihe River in the central-west Loess Plateau for analysis of distribution characteristics of main elements,including K,Na,Ca,Mg,P,Fe,Al and Ti.Results showed that Ca has the strongest migrating capacity,followed by P,Na,Mg,K,while Fe,Al,Ti are relatively steady.K,Fe,Al,Ti were relatively enriched in the buried paleo-surface horizon(2A) and paleo-argillic horizon(2Bt),where natural pedogenic eluviation and illuviation played a main role.While,Ca,Na,Mg and P showed lower contents in above horizons,especially Ca,due to their relatively high mobility under natural environment.The eluviation of carbonate under warm and humid condition resulted in the relative enrichment of K,Fe,Al and Ti in the buried paleo-surface horizon(2A) and paleo-argillic horizon(2Bt).Effect of human activities on the contents of main elements in Earth-cumuli-Orthic Anthrosols was mainly reflected only in the enrichment of nutrient elements such as C and P in buried plow horizon and modern plow horizon.