Abstract: A comparative study on meteorological and hydrologic factors of forest vegetation andgrassland in subtropics of Guanxi shows that inside the stands with larger crown density,the annual mean temperature and its range are 0.1-0.7℃ lowe, but the annual meanralative humidity is 0.7-6.7% higher than outside. The annual mean temperature andits range at the ground and at the same soil horizon inside the stands are respectively 2.3-7.8℃ and 1.6-4.6℃ lower than outside. The annual mean water surface evaporationinside the stands is 51.3-73.0% lower than outside, and the canopy interception occupies by 9.9-15.8% of precipitation, the stemflow by 0.5-3.3%, and throughfall by 83.9 - 88.0%. The maximum moisture capacity in the litter layer of forest land is 4-13 times larger than that on grassland. The annual mean surface runoff on forest land is 0.46-22.3mm, 35.2-93.8% lower than that on grassland.

Key words: Forest vegetation, Climate, Ecological function, Subtropics