Variation Of Soil Respiration In The Terraced Ecological Ecosystems And Their Relationship With Environmental Factors In The Horqin Sandy Land

The paper,the six sandy ecosystems including the bare dune land,the Artemisia halodendron community,the Salix gordejevii,dune-meadow transition zone,the Leymus chinensis and Artemisia halodendron community,the meadow Phragmites australis and the Artemisia abrotanum in the Horqin cascade ecobelt were planted.The study object was to use the Li-6400-09 soil respiration measurement system to observe the daily and seasonal changes of soil respiration during different periods of the growing season.The automatic weather stations were used to monitor the environmental factors of various ecosystems for a long period of time to explore the changing patterns of soil respiration and their The response of the impact factors is expected to provide a theoretical basis for the management of the soil carbon pool and desertification control of Artemisia halodendron community and bare land in the dunes-meadow arid and semi-arid area of the Horqin sand.The main conclusions were as follows:?1?The seasonal changes of soil respiration under the cover of dune vegetation?Artemisia halodendron community?showed a significant increase under vegetation coverage?P<0.01?.The seasonal changes in soil respiration at different slopes covered by sand dune will show that the downslope is larger than the mid and uphill slopes?P<0.01?.In addition,the changes of soil respiration in the dunes showed that the nocturnal soil respiration was higher than that in the daytime.?2?The diurnal variation of soil respiration in the meadow Phragmites australis and the Artemisia abrotanum was significantly correlated with only partial diurnal variation of soil temperature.The seasonal variation of soil respiration in the meadow Phragmites australis and the Artemisia abrotanum has significant index positive correlation,with soil temperature,and the number of soil bacteria has been significantly positively related to the power function,but no significant correlation between soil moisture content and,in this study for meadow ecosystem enough moisture,soil temperature are the main controlling factor of the season change.?3?The seasonal variation of soil respiration in six ecosystems in the cascade ecosystem was significantly different?P<0.05?.Growing season at the same time?8:00 to10:00?average of soil respiration is Phragmites australis community(11.19?molm^-2s^-1)>meadow Artemisia abrotanum community(7.75?molm^-2s^-1)dune Salix gordejevii(6.78?molm^-2s^-1)>transitional zone south of the lake,Artemisia halodendron(4.87?molm^-2s^-1)>lake north transitional zone north of the lake,Leymus chinensis(4.28?molm^-2s^-)>Bare Sand Dunes(3.09molm^-2s^-1).The Q₁₀ values of temperature sensitivity were as follows:Bare Sand Dunes?1.11?,lake north transitional zone north of the lake,Leymus chinensis?1.12?,meadow Phragmites australis community?2.36?,meadow Artemisia abrotanum community?2.34?,ansitional zone south of the lake,Artemisia halodendron?1.77?,Salix gordejevii dunes?1.89?.There was no significant difference in soil temperature?P>0.05?,but there was significant difference in soil water content and soil bacteria?P<0.01?.?4?Due to the ecological system of the main factors affecting soil respiration in time and space differences,the relationship between soil respiration and impact factor,bare dunes,Salix gordejevii dunes,transition zone Leymus chinensis and the transition zone Artemisia halodendron four ecosystems are correlated with soil temperature was not significant?P>0.05?,the bare dunes,transition zone Leymus chinensis and transition zone Artemisia halodendron with soil moisture content was significantly positive correlation?P<0.05?,and the seasonal change form is mainly controlled by soil moisture,and sand dunes Salix gordejevii because of the influence of the vegetation,and soil moisture was significantly negative correlation?P<0.05?.meadow Phragmites australis community and Artemisia abrotanum community both ecosystem and soil temperature show a significant positive correlation?P<0.05?,and the soil moisture content was significantly negative correlation?P<0.05?,the seasonal change form by the combination of soil temperature and soil moisture content.Microbial respiration as part of the soil respiration,soil respiration were six ecosystem with the power function of the number of soil bacteria has been significantly positive correlation?P<0.01?,and meadow ecosystem soil bacteria number greater than the dunes ecosystem.The research results provide references for revealing the changing rules of soil respiration in semi-arid desertification areas.