The Effect Of Bioorganic Matter On Travertine Sedimentation And Degradation In Huang Long Scenic Area

Huanglong Natural Scenic Area is a travertine scenic spot dominated by the Kashite landforms,enjoying the title of World Natural Heritage and National Natural Scenic Area.In recent years,with the development and utilization of tourism resources in the Huanglong Scenic Spot and tourism activities and other factors,the scenic travertine pools and ancient travertine ponds have undergone repeated degradation phenomena such as dissolution,blackening,and desertification.According to previous studies,in addition to the impact of tourism activities,a large number of biological organisms,such as vegetation and algae produced directly or indirectly,in the Huanglong scenic area also have an influence on the deposition and degradation of travertine,in order to systematically study the effects of bio-organic matter on Huanglong water body and travertine deposition and degradation,this research team collected the waters of the Huanglong scenic spot and different types of travertine in the May,August and October of 2016.Through the application of relevant water quality analysis,elemental analysis,XRD,XRF,FI-IR,SEM,UV-vis,EEMS and other testing methods,the quality of water quality in different locations and the types,morphology,composition,and participation of organic matter in different types of travertine crystals were studied preliminarily,The degree of participation of organic matter in water bodies and travertine was key studied.The results of the study were as follows:?1?Huanglong water p H and conductivity showed a slow rise?p H?and decrease?Ec?trend with altitude.The changes of Ca²⁺,SO₄^2-,Mg²⁺,and HCO₃^-ions in water bodies at different measurement sites are more complex with the seasons,The main reason for this is that water is affected by displacement in different periods on the one hand,and the phenomenon of run-off and stagnant water occurs in some areas,the water bodies cannot get the same degree of update,On the other hand,due to tourism and seasonal environmental influences,algae and other growth conditions at different locations have different effects on the ions contained in water bodies.?2?accordding to statistical analysis of a large number of water quality data found that changes in TP,TIC,TOC,etc.in the environment have important effects on the deposition and degradation processes of travertine.TIC is mainly related to HCO₃^-and CO₃^2-related to travertine deposition in the water.TP mainly affects the seasonal changes of algae,and the assimilation and dissimilation of algae in the process of growth will produce a large number of bio-organic metabolites.With the change of time and the influence of the environment,metabolites will be corrupted and form a large amount of organic matter,this in turn affects the TOC content of the water.?3?Through the determination of FA and HA in different degenerate travertine,There is a big difference in different travertine organic materials were the absorbances of SUVA₂₅₄54 and SUVA₂₈₀?the ratios of E2/E3 at 250nm and365nm?the ratios of E3/E5 at 350nm and 550nm and the ratios of E4/E6 at465nm and 665nm,which shows that there are some differences in the degree of travertine corruption and there are also differences in the degree of corruption of organic matter in different travertines body.?4?In addition to the formation of large amounts of calcite-type calcium carbonate,newly deposited travertine also forms a small amount of aragonite-type calcium carbonate,during the course of its crystal research,it was found that although it was newly deposited travertine,its crystal shape also occurred,different degrees of change,the diffraction peak height and peak width appear different,indicating that the crystallinity,crystal integrity,etc.of travertine crystals are different.This phenomenon is also confirmed by SEM pictures,The completeness of the crystal is damaged to varying degrees,It is found that the rhombus and the surface are corroded and the pore structure appears.It shows that travertine is affected by external factors in the sedimentary composition,which makes the growth appear distorted.In addition,during the analysis of the composition of the newly deposited travertine,it was found that in addition to calcium carbonate,there are inorganic elements such as N,S,Si,Al,Fe,K,S,Sr,P,Mg,and Ba in the crystal,and there are organic compounds such as organic acids,which contain functional groups,such as carboxyl,methyl,aldehyde group,etc,fatty acids,and sugars,It can be proved that the biological participation and influence of Huanglonggou travertine during deposition.?5?For different types of degraded travertine research,it has been found that the apparent structure and internal microstructure of different degraded travertine samples are different from those of newly deposited travertine.It is found by XRD that the degenerated travertine crystals contain calcite type calcium carbonate and a small amount of aragonite type calcium carbonate,they were basically the same as newly deposited travertine,however,the crystallinity of crystals differs greatly from newly deposited travertine,and the degenerate travertine crystallinity is only about 24.50%-62.74%.In addition,the degenerate travertine crystals are destroyed compared to the pure calcite-type calcium carbonate,the crystal plane spacing increases,and the crystal lattice appears distorted.The surface has undergone dissolution and etc,which are involved in the action of algae and etc.There are a large number of organic-like particles attached to the surface,with different degrees of differentiation,sandification and other serious effects,which performs the surface structure is loose,scattered shape,the lower adhesion between travertine particles.It can be seen that degenerative travertine shows different degrees of degradation.?6?Study of new sedimentary travertine deposits at different depositional sites have been found that they also contain large amounts of Ca and a small amount of Si,Mg,Al,S,Fe,Sr,K,Na,P,Ba,and Cl.In addition to the characteristic absorption peaks of calcite in different degenerate travertines,there are also substances containing a large number of functional groups,namely the presence of organic substances such as phenols,organic acids,fatty acids,ketones,esters,aldehydes and aromatics,etc.It shows that the degenerate travertine contains different organic substances,andinfrared peak and the peak area also have different changes,indicating that the types and content of organic matter are also different.In summary,the travertine of Huanglong is directly or indirectly influenced by the surrounding environment and human tourism activities,in addition to being affected by the water flowrate.The changes in water quality caused by these effects eventually lead to changes in aquatic organisms?algae,microorganisms,etc.?,and reverse affect the water quality of the water bodies,eventually leading to changes in the deposition and degenerate processes of travertine.The results of this study to a certain extent expounded the participation of substances in the degenerate process of travertine and the results of the degenerate of travertine,which has certain significance for the protection of Huanglong travertine and the rational development and utilization of scenic travertine landscape.