3.2. Effect of mulch thickness on soil temperature
Figure 2 shows the trends of daily soil temperature at 5 and 10 cm depths for mulch thickness treatments. The daily soil temperature in the 11 cm mulch thickness treatment was very similar to 9 cm mulch thickness treatment. The results indicated that the soil temperature at 5 and 10 cm depths was higher for all mulched treatments than for the non-mulched ones from 23:00 (night) to 8:00(morning), and increased slightly with increased thickness of mulch(Fig. 2).