| Frame structure of stadium interdicts direct convection of air inside and outside, resulting in a relatively closed microenvironment in stadium. Turfgrass is plant with life and changes of environmental factors in stadium could affect turf growth and quality. At present, systematic research on the microenvironment of the stadium and its effects on turfgrass growth are seldom. A simulated Nest-type National Stadium was built in this study and four experiments were carried out with tall fescue during the summer and winter of 2006 and 2007, respectively. The first was effects of simulated nest-type stadium on the growth environment of sports turf. The second was effects of simulated nest-type stadium on the growth of tall fescue in summer. The third was effects of root-zone cooling on the growth improvement of tall fescue in simulated nest-type stadium. The fourth was effects of simulated nest-type stadium on the growth of tall fescue in winter. The main results were as follows:Frame structure of stadium led to shade environment. Light intensity and direct radiation time in simulated stadium were significantly lower than the outside control. In summer average light intensity and direct radiation time in simulated stadium were only 23.98%～68.07% and 12.08% of the control, respectively. In winter average light intensity and direct radiation time in simulated stadium were only 8.00%～60.47% and 3.34% of the control, respectively. However, temperature in simulated stadium was significantly higher than the outside control, showing that there was a significant heat accumulation in it. The highest air temperature increases were 7.8℃and 7.5℃, and extreme air temperature were 45.3℃and 45.8℃in simulated stadium during the summer of 2006 and 2007, respectively. The increase of temperature in simulated stadium could make turf high quality management more difficult in summer. Heat accumulation in winter was lower than that in summer in simulated stadium. The highest air temperature increase was 2.4℃during the winter of 2006. Relative humidity in simulated stadium was also significantly higher than the outside control. The average relative humidity increases in simulated stadium were 2.9% and 3.0% in the summer of 2006 and 2007, respectively. In the winter of 2006 the average relative humidity increase was 6.7% in simulated stadium. The increase of temperature in simulated stadium dramatically affected the growth of tall fescuse in summer, accelerating the decline of turf quality. Turf quality and growth had been significantly lower than the control since July 23/24 and 20/21, respectively. Turf quality had decreased to below the acceptable level (6.0) since August 8/9. Leaf chlorophyll content had also decreased significantly compared to the control since July 28/29. However, leaf electrolyte leakage had been significantly higher than the control since August 6. MDA content in leaves had also increased significantly compared to the control for about half of the experiment period.Technique of root-zone cooling significantly reduced the root growth temperature of turfgrass in simulated stadium. Root-zone temperature at 10cm depth in Nest1 (treatment) was significantly lower than that in Nest2 (control). The average decreases were 5.11℃and 7.31℃, thus the root-zone temperature at 10cm depth in Nest1 reduced to 30.97℃and 27.78℃. The decrease of root-zone temperature in Nest1 significantly improved the growth of tall fescuse in simulated stadium. Turf quality and growth had been significantly higher than Nest2 since July 23/24 and 20/21, respectively. Leaf chlorophyll content had also increased significantly compared to Nest2 since July 28/29. Turf canopy net photosynthetic rate was significantly higher than Nest2 since July 23 in the year 2006, and the highest increase was 105.4% of Nest2. Turfgrass root activity had also increased significantly compared to Nest2 since July 25 in the year 2007, and the highest increase was 35.1% of Nest2. However, leaf electrolyte leakage had been significantly lower than Nest2 since August 6. MDA content and soluble sugar content in leaves had also decreased significantly compared to Nest2 for about half of the experiment period.The increase of temperature in simulated stadium prompted shoot vertical extension rate in winter, which had been significantly higher than the control during the period of December 16, 2006 and January 6, 2007. However, low light condition in simulated stadium significantly inhibited the growth of tall fescuse. Turf quality, density and turfgrass tiller, shoot dry weight, leaf chlorophyll content and soluble sugar content had been significantly lower than the control since the beginning of the experiment.
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