沈阳城市森林三维绿量测算

为了探讨城市森林三维绿量的测算方式及精度,该文利用2001年8月沈阳市真彩航片和抽样调查,借助ARC/GIS,以“立体量推算立体量”的方法测算沈阳城市森林三维绿量结果表明,不同城市森林类型的单位面积三维绿量以风景游憩林最高,为5.35 m3/m2,附属林4.93 m3/m2,道路林3.65 m3/m2,生态公益林3.62 m3/m2,生产经营林2.35 m3/m2;城市森林分布区的单位面积三维绿量为4.25 m3/m2;城区单位面积城市森林三维绿量为0.35 m3/m2.沈阳城市森林总体三维绿量为161 296 716.85 m3,其中附属林为60 116 966.36 m3,37.27%,生态公益林43 321 771.43 m3,占26.86%,风景游憩林30 482 879.04 m3,占18.90%,道路林23 841 208.75 m3,占14.78%,生产经营林3 533 891.27 m3,占2.19%.经检验,该方法精度达到85.50%（α=0.05）. 

Tridimensional green biomass measures of Shenyang urban forests

In order to study the measurement method of urban forest tridimensional green biomass(TGB) and its ratio of precision with true color aerial photo and ARC/GIS, using a method of “estimating tridimensional volume by tridemensional volume", the TGB of urban forests of Shenyang in August 2001 was measured. TGB per unit area of recreation forests was 5.35 m3/m2, which was the highest of urban forest types. The TGB of subordinated forests, road forests, ecological and public welfare forests, and production and management forests were 4.93, 3.65, 3.62 and 2.35 m3/m2. TGB per unit area in urban forest distribution area was 4.25 m3/m2 and that in Shenyang urban area was 0.35 m3/m2. Total TGB of Shenyang urban forests was 161 296 71685 m3. Subordinated forests, ecological and public welfare forests, landscape and relaxation forests, road forests, and producti on and management forests accounted for 37.27%, 26.86%, 18.90%, 14.78% and 2.19% of the total, and their TGB were 60 116 966.36, 43 321 771.43, 30 482 879.04, 23 841 208.75 and 3 533 891.27 m3 respectively. Having checked this method, its ratio of precision was up to 85.50% (α=0.05).