关键词:
Biomass
Crown cover
Forest type
Himalaya
Landuse
Remote sensing
摘要:
In the present study, forest biomass mapping and estimates were carried out for a watershed in Garhwal Himalaya using stratified approach. IRS-1B, LISS II data of May 1994 with four spectral bands of spatial resolution 36.25 m were used for forest type and crown cover mapping. The forest type-cum-crown cover map was used as a major base for forest biomass mapping, which was then integrated with 'crown cover-biomass model'. Stand biomass for each site was computed from ground inventory using mean cbh, density and generalized species and interspecies allometric equations. Stand biomass values were related to the crown cover through allometric equations. Using these equations and mean crown cover for each individual class, mean biomass was computed for various components. The total biomass for each forest type was computed by using mean values and the areal extent of the class. Of the total geographical area of 113.50 km2, non-forested land occupied 54.1% area. Forest cover was distributed in five forest types and stratified into three crown cover classes ranged viz., 21-40%, 41-60% and 61-80%. About 6.8% of the forest area (i.e. 3.1% of total area) was under 61-80% crown cover. Crown cover of >60% was encountered only in mixed conifer forest. The forests with >40% crown cover occupied 78.2% of forest land (i.e. 35.8% of the total area). Total above ground biomass in entire study area including village woodlands was 1217.94×103 t out of which 130.31×103 t was in village wood-lands. Among different forest types maximum biomass was found in Pinus roxburghii forest (315.55×105 t). © International Society for Tropical Ecology.