The upper species limit shift of Abies spectabilis and its tree line dynamics under climatic
stress was studied in A. spectabilis forest of Lho village in Manaslu Conservation Area,
central Nepal. The census of A. spectabilis was carried by belt transect laid covering tree line
as well as tree species limit and the sample belt was located by purposive sampling method.
Total number of tree individuals, basal diameter, diameter at breast height (DBH), and crown
diameter, number of seedlings and saplings of A. spectabilis were recorded. Tree age was
estimated by tree-ring counts and the count of branch whorls and bud scars in sapling and
seedlings. Two LANDSAT MSS imageries of year 1976 and 2001 were used to delineate the
change in vegetation. The area of interest of altitudinal belt of 3,700m to 4,200m was
generated and the vegetation change was analyzed. The analysis of the precipitation and
temperature data of 30 years (1971-2010) showed that there was an increase of mean
temperature by 0.10o
C per year and decrease in precipitation by 1.777mm per year. The
establishment of the species in the study area was dated back to 1900. Total 76 individuals of
tree, 112 saplings and 77 seedlings were recorded. The recruitment of A. spectabilis was
positively correlated with mean annual temperature (r = 0.35, P = 0.04) and negatively
correlated with mean annual precipitation (r = -0.36, P<0.5). Between the periods of 1900
and 2012 A. spectabilis upper limit has shifted at a rate of 10.8m/year with the upslope
shifting of 110m with 1911 tree line reference. Similarly, the NDVI analysis of the Landsat
images has shown 9.06sq.km of non-vegetated area in 1976 have turned to vegetated area in
2001.