Abstract:
The paper presents
experimental results reported for a period of
24 years, during 1985-2008, on runoff and
erosion processes, measured on some runoff
plots. They are located on the left hillside of
the Upper Tărnii Valley, Eastern Romania,
on mollisols (Cambic Chernozem),
developed on top of loams, moderately
eroded, with a 12% slope. The average of
multiannual precipitation is 492.2 mm.
From the total of eight plots, six of them are
100m2 (25×4m with 1 m border areas
between them) and the other two are 150 m2
(37.5×4m). Six plots were cultivated with
different crops as follows: corn, beans,
soybeans, winter wheat and bromegrass.
Two check plots of 100 and 150m2 were
maintained like black fallow, always free of
weeds. Also, annually one of the crops is
cultivated both in the 100m2 and 150 m2
variants. Averages of soil losses in the study
period of time were 0,16 to/ha/y for
bromegrass, 0,86 to/ha/y for winter wheat,
5,60 to/ha/y for Beans, 9,30 to/ha/y for corn
and 43,12 to/ha/y for black fallow. The
intensity of erosion processes has been
marked by some historical rainstorm events
that have exceeded the value of 80 mm for
which the soil losses ranged between 20 and
35 to/ha/y for the black fallow check plot.
During the period of vegetation maximum
peak erosion rates for winter wheat and
beans were registered in May while for the
rest of crops and for the black fallow
maximum values were noticed in June.
