Effect of Mowing Frequency on Characteristics of Soil Respiration of Mixed Turfgrass

Mixed turfgrass consisting of Poa pretensis and tall fescue in front of the Herbage Seed Pavilion at Chinese Agricultural University was researched.Diurnal dynamic characteristic of turfgrass soil respiration rate among different mowing frequencies was measured using Li-8100 system.Results showed that the diurnal variation of soil respiration rate presented a monopeak curve for mowing once a week,mowing once every two weeks and common practice(control).The maximum soil respiration rate appeared at 12:00-14:00 for all treatments,whereas the minimum soil respiration rate appears inconsistent for all treatments.Annual total soil respiration output of turfgrass had no significant difference among all treatments in June and July.Annual total soil respiration output of turfgrass mowed once every two weeks had significant difference in August compared with that of turfgrass when mowed once a week and the control.There was no significant difference between the turfgrass mowed once a week and control.There was a significant positive correlation as a whole between soil respiration rates and soil temperatures at five cm depth in all treatments.However,the correlation between soil respiration rates and other temperature indicators varied for different months and different treatments.Q10 value of turfgrass soil respiration was increased with soil depth increasing.