Abstract:
The natural forest in Tabalong District has been degraded, proved by the
fact that Ulin trees (Eusideroxylon zwageri T. & B.) are rarely to be found. Ulin is in
the status of endangered species, thus it must be protected and under the development
efforts. Therefore, it needs information of the optimum growing requirements. The
aim of this research is to analyze the relationship between land characteristics with
the presence of Ulin. The data required are primary data collected by sampling
method and secondary data by indirectly through institutions. Sampling was done by
line observations followed the mapping unit representation which consists of land
system majority, elevation, and slopes. Transects made the cut contour, thus the line
observation represent the condition of ecological site from the lower land to the upper
land. Data collection include data spatial of Ulin, relief, climate and soil sample. Land
system and relief spatially analyzed using geographic information systems, while the
land characteristics analyzed in the laboratory.
The results of this study are optimum growing requirements on the attributes Ulin
temperatures ranging from 25-32 oC, the availability of water (w): the number of dry
months <3 month per year, rainfall >2000 mm per year, rooting medium (r): soil
permeability is medium class, soil texture is sandy clay, soil effective depth >50 cm,soil porosity 55-65 percent, field capacity water >45 percent, nutrient available (n):
does not require sufficient nutrient supply with low-grade organic C and relief (s) of
slope <25 percent.
