Research Oil The Mineralization Characteristic Of Soil Organic Matter In The Estuary Wetland

Estuarine wetlands are primarily terrestrial buffer spaces for the ocean material transport. With the rapid development of the city, a lot of nutrient substances go into the inland river. Nutrients are carried by the river passing estuarine wetlands and go into the ocean. This creates a great impact on soil physical and chemical environment in the wetland. Pigeon-nest wetland in Qinhuangdao City of Hebei Province and Shuangtai river wetland in Panjin City of Liaoning Province are all National Wetland Nature Reserve. They are in the half-open-sea environment in Bohai Bay and their soil micro-environment are very special. They are affected by anaerobic conditions produced by periodic flooding and sea salt cyclically. Compared with terrestrial soil, it have a lot of particularity such as earth science, hydrology, chemistry, biology, etc.Firstly, this article established an indoor simulation experiment to explore the biochemical properties of the soil base changes in 300 days. Secondly, do field positioning sampling continuously for one year(April to December) on the two wetland soils to explore the estuarine wetland soil organic matter source and monitor the changes of soil organic matter, microbial biomass and other indicators between different months under natural conditions. Third, revealed spatial and temporal variability of organic matter content by using Arc GIS software. Finally, using Corn leaves, Scytosiphon lomentarius, Suaeda glauca and sucrose as exogenous material to research the priming effect on soil carbon in the estuarine wetlands. The conclusions are:(1) Compared with the soil under natural conditions, the soil organic matter content is slightly lower, microbial biomass content is higher, Soil p H values is slightly in the incubator. In incubator, the soil organic matter content had a downward trend in 0-30 days, then go to a stable state. Soil microbial biomass showed an increasing trend in 0-60 days. After 60 days, Pigeon-nest wetland stabilized after a slight decline in the state of content. Shuangtai river wetland had a downward trend in the first 60 days, and go down to the flat state with the started after 150 days. Soil p H had a decreasing trend in 0-60 days and then restored to its original size gradually.(2) Through a one-year field study of continuous monitoring sampling, we found that soil organic matter in estuarine wetland mainly came from the litter decomposition of wetland plants and marine plants. On terms of soil organic matter content, the Pigeon-nest wetland increased from April to July and go into a stable state soon. From October the soil organic matter content decreased to the level of April until the soil into the frozen state. Shuangtai river wetland increased from April to June gradually and then began to decrease. After August had the same content with April and then stay in a steady state. On terms of soil microbial biomass, the Pigeon-nest wetland increased from April to August and go into a stable state soon. And it declined from October to December, and go to the May level before the soil began to Froze. Shuangtai river wetland increased from April to August gradually and then began to decrease until the same with June. The soil organic matter and soil microbial biomass had a significant positive correlation.(3) Soil organic matter content has a certain temporal variability in Pigeon-nest wetland. In time, the maximum organic matter content 6.14 g/kg is in summer of the year and the minimum organic matter content 1.46 g/kg is in winter. The average of organic matter content is 2.87 g/kg. The range of soil organic matter in spring, summer, autumn and winter are 1.61~3.96 g/kg, 1.65~6.14 g/kg, 1.81~5.17 g/kg, 1.46~5.16 g/kg. Soil organic carbon storage in order to increase by spring,summer,winter and autumn seasons in Pigeon-nest wetland. From winter to spring until go to winter, the changes are reduce 93.07 t, increase 77.63 t, increase 108.93 t, reduce 93.49 t. In space, The spatial pattern of SOM content distribution showing an overall trend from west to east.(4) Experimental results of priming effect of soil organic matter show that, totally, put exogenous in Shuangtai river wetland the priming effect was demonstrated significantly higher than the Pigeon-nest wetland. Add scytosiphon lomentarius in Pigeon-nest wetland we fond negative priming effect. But if add others we fond positive effect. Add all substance in Shuangtai river wetland we fond positive effect. Corn leaves as a foreign substance added to soil, Pigeon-nest wetland had a positive effect in the first 7 days and turned to negative effect from 7 days to 28 days. Shuangtai river wetland and Pigeon-nest wetland is completely opposite. Scytosiphon lomentarius as substance, it showed positive excitation in Shuangtai river wetland and in Pigeon-nest wetland the first 7 days is positive excited and then turned to negative excitation. Suaeda glauca treatment are all showed a significant positive excitation in the two kinds of soil. But the effect showed a decreasing trend. Sucrose as exogenous material, it had a positive excitation until the 14 th day in Pigeon-nest wetland. After that it turned to negative excitation. It had a positive excitation in the all 28 days in Shuangtai river wetland. But it was a little stronger in the first 14 days and go weak latter.