Effects Of Vegetation On Soil Carbon, Nitrogen, Phosphorus And Some Enzyme Characteristics Of Tidal Flat Wetland In Liaohe Estuary

The study of the physical and chemical properties of the sediments under different vegetation conditions in the tidal flat of Liao river River,the changes in the ecological measurement of soil carbon,nitrogen and phosphorus,and the characteristics of some soil enzymes are of great significance for understanding the ecological conditions of the tidal flat wetland in Liao river mouth.In this paper,the stratification and soil enzyme activity of the sediments were measured by field sample collection and laboratory analysis in the area of reed growth area and barren beach area in the tidal flat of Liao river River Estuary.The following are discussed:(1)changes in physical and chemical properties of tidal flat sediments at different growth stages.(2)changes in physical and chemical properties of sediments in tidal flat wetlands.(3)Soil Eco stoichiometry characteristics of tidal flat wetland sediments at different growth stages and different vegetation types.(4)the activities of cellulase,alkaline phosphatase and nitrite reductase at different growth stages in tidal flat wetland.The results were as follows:(1)the vegetation types of the tidal flat wetland in Liao river estuary affected the carbon,nitrogen and phosphorus content and the activity of cellulase,alkaline phosphatase and nitrous reductase;(2)the C:N ratio in the tidal flat wetland of Liao river River Estuary was the same in the upper and lower layers in different periods,and the maximum fluctuation in July was the smallest in September;(3)The C:P ratio of the Liao river estuary wetland sediment vegetation growth zone varies greatly in different periods,and the C:P ratio in different periods is 28~136.(4)the N:P ratio of the sediments in the Liao river estuary wetland is lower than the N to P ratio of 5.2 in the soil of our country(250 cm depth).The N:P ratio in the upper layer of the wetland sediments is higher than the lower layer and the sediment N:P under the different vegetation conditions.(5)there was no significant correlation between the activity of soil cellulase and alkaline phosphatase and the value of pH,and the negative correlation between the nitrite reductase and the pH value(P<0.05),and(6)the activity of alkaline phosphatase and nitrous reductase was positively correlated with the content of soil organic carbon(TOC)(P<0.05 There was no significant correlation between the content of cellulose reductase and soil organic carbon(TOC)(P>0.05);(7)there was no significant correlation between soil alkaline phosphatase and total phosphorus(TP)content,and there was a significant positive correlation between soil nitrous reductase activity and total nitrogen(TN)content(P<0.05),and(8)the same region fiber at different growth stages.The activity of the enzyme,alkaline phosphatase and nitrous reductase is different,the activity of the soil enzyme in the upper and lower layers is different,the trend of the changes in the upper and lower layers of the nitrous reductase activity in different growth periods is the same,and the nitrous reductase in the tidal flat wetland of Liao river River in July is higher than that of the other months.