Abstract :
Indigenous stands of tropical rain forests in the region of Kon Ha Nung are one of the most preserved
forests in the whole Vietnam. Despite the logging activities mainly in the 1970’s, it was possible to
preserve intact forests free from any primary harvesting. In the past, other stands were infl uenced
by the logging to various extent. Some of those stands are managed presently; others were le to
natural development. This paper deals with the infl uence of harvesting activities on the root system
in forest stands. In primary stands and in stands with known harvest intensity, samples of root systems
were collected. The total weight of dry basis and mainly their layering within the soil profi le were
assessed. The collected roots were divided into three classes: class I – ? 1.0 mm, class II 1.1–5.0 mm,
class III – over 5.0 mm in the diameter. In the monitored plots, the total weight of dry basis of fi ne
roots to 1.0 mm ranged from 2.34–3.24 t·ha?1. The weight of dry basis of roots from 1.0–5.0 mm ranged
from 6.57–9.69 t·ha?1. The majority of roots of class I is presented in the top 10.0 cm of the soil and
their share drops with the increasing depth. The roots of class II are distributed more equally. It was
impossible to prove the infl uence of the logging on the root system.