Silviculture and Cinegetics Review - Societatea Progresul Silvic

FORESTRY BELTS SILVICULTURE AND CINEGETICS REVIEW XVII/30/2012
mercury containers shaded with paper cones, and the
soil thermometers were provided with metal housing.
The results in the table highlight the net differences
between forest and grassland temperatures, as well as
between soils and air.
Thus, at 7 AM, the average difference between forest
and grassland temperature is of 1°C in the air and of
0.5°C in the soil, growing at 13 00 , up to 4.2°C in the air
and 3.1°C in the soil on the grassland compared to the
forest.
With the help of thermal micro-gradients it was
possible to draw up temperature’s evolution from 10 to
10 cm high in the air and deep in the soil. (Maruşca and
Filip, 1995) (Figure 1).
The highest changes of the thermal micro-gradients
were recorded on intervals of 0–40 cm in the air and soil
especially in the grassland where they are of -1.6°/10
cm (17.2-14.0°C) in the air and -2.8°C (16.0-10.4°C) in
the soil.
In the forest the air and soil temperatures are more
constant, being recorded subunit values for microgradients,
confirming the protective role of woody
vegetation compared with other ways of land use.
The thermal regime of air (0-200 cm high) and soil (0-
150 cm deep) of woody vegetation is lower and more
stable in comparison to that of herbacous vegetation
during the growing season (May-September) at 1100 m
altitude.
The average thermal micro-gradients in the air are
absent in the forest on the interval 50-200 cm high from
the soil (11.5 0 C) and have a slight decrease in the
grassland of -0.04°C/10 cm (13.1-12.7 0 C) at the same
height.
In the soil, at a depth of 50-150 cm, the micro-gradients
are equal, respectively -0.08°C/10 cm, but with the
average limits of 8.7-8.3 0 in the forest and 10.3-9.9 0 C in
the grassland.
These data show once again, if it’s needed, the
thermoregulator role of forests in the mountain area
climate.
Fig. 1.Thermal micro gradient evolution of mountain forest
and grassland ecosystems during the growth season
(Apuseni Mountains 1100 m altitude)
3.2. Communal pastures with trees
Given the characteristics of the more balanced
microclimate of the forest compared to the extreme one
of the open fields, for farming, since immemorial times,
in our country as well were carried out works of
thinning of existing forests in order to install the grassy
in our country as well were carried out works of
thinning of existing forests in order to install the grassy
carpet of grasslands for fodder, action called
“dumbrăvire
In areas where forest was completely cleared, on the
resulting pastures solitary trees were then planted, in
clusters and/or alignments for animals sunburn
protection while also obtaining wood necessary for
households.
The action of “setting” the groves with planted
seedlings can be called dumbrăvuire as the creation of
forest belts on arable land is called perdeluire
(Ianculescu, 1990).
Thus, using the two methods dumbrăvire and
dumbrăvuire related the well known groves or open
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