LUO Shao-yong1, ZHOU Yue-fei2，LIU Xing1
( 1.Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China；
2. School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, China)
Abstract: Seven sets of drilling cores of recent sediments from the Dianchi Lake in Yunnan Province have been collected in this paper. The contents of P (TP), Fe, Al and Ca of the sediments, have been analysed. It is first time to have obtained data of various forms of P in sediments buried deeper than 25 cm. The temporal and spatial distribution characteristics of total P (TP) and various forms of P, as well as the relationships between TP and Fe, Al and Ca contents were explored. Subsequently, the controlling factors and regional differences of the release potential of endogenous P in the Dianchi Lake have been discussed. The results show that TP contents of sediments are gradually increased at first and then decreased with the increase of depth, from north to south areas of the Dianchi Lake. Contents of various forms of P are subsequently decreased with an order of detrital P (DP) > organic P (OP) ≈ Fe-bound P (Fe-P) > occluded P (OcP) > Ca-bound P (Ca-P) > Al-bound P (Al-P) > soluble reactive P (SRP). Vertically, the Fe-P contents are gradually increased but the OcP are gradually decreased with the depth, while there is no obvious variation regulation for contents of other forms of P with the depth. Horizontally, contents of the TP, DP, OP, Fe-P, Ca-P, and Al-P of sediments in southern part of the Dianchi Lake are higher than those of sediments in the northern areas. In the southern Dianchi Lake where sediments contain relatively high contents of DP, there are positive correlations between the TP and respective Fe and Al contents of sediments, but there is a negative correlation between the TP and Ca contents. However, such correlations have not been found for sediments in other parts of the Dianchi Lake. This implies that the release potential of endogenous phosphorus of sediments in the southern Dianchi Lake is higher than those of the central and northern parts. The endogenous phosphorus of sediments in the southern Dianchi Lake is mainly influenced by the input of DP. However, the release of endogenous phosphorus in the northern Dianchi Lake is relative strongly inhibited by the wind wave disturbance.
Keywords: Dianchi Lake; recent sediment; terrigenous source; phosphorus; mode of occurrence; environmental effect
ACTA MINERALOGICA SINICA Vol. 39, No.1, 2019, page 15-22
