Abstract: Taking the coastal Metasequoia glyptostroboides backbone protection forest belt in Pudong District of Shanghai as test object, this paper assessed the changes of stand canopy and soil property after thinning and after planting other trees under thinned stands. The results showed that both the thinned and the two-storied stands promoted the growth of upperstory tree height and diameter at breast height significantly, and also, accelerated the understory vegetation development. The leaf area index (LAI) was the highest in un-thinned M. glyptostroboides stands, followed by in two-storied stands, and in thinned stands. The gap fraction distribution of the three kinds of M. glyptostroboides stand was contrast to LAI. The total N, total P, and available K contents of the soils in the three kinds of M. glyptostroboides stand had no significant differences, while the soil available P, hydrolyzable N, and organic matter contents were higher in thinned and two-storied stands than in un-thinned stands. There was no significant difference in the soil nutrient contents between the thinned and two-storied stands. Forest structure control increased the soil organic carbon (SOC) storage in 0-50 cm layer, and the SOC density was the highest in 0-15 cm layer. The soil respiration in two-storied and thinned stands increased by 42% and 33%, respectively, compared with that in un-thinned stands.

Key words: Landscape ecological assessment, Landscape ecological planning, GIS