in contrast to the infertile desert, the
‘red land’ (Schoske et al. 1992: 15). Since in Ethiopia today state control of
deforestation is less strict than formerly, erosion in the Ethiopian Highlands
has increased, so that the amount of silt transported by the Nile should have
become greater in recent decades. The seasonality of the Nile discharge due
to the monsoonal rains was the reason why formerly the Nile run-off at
Aswan in September was usually about thirteen times as great as in April.
The variability was not only seasonal but annual, corresponding with the high
rainfall variability in Ethiopia. Extreme discharges measured at Aswan were
141.6 billion m3
in 1878/79 (Said 1993: 140) and 34.8 billion m3
in 1983/84
(El-Naggar 1999: 119).
‘red land’ (Schoske et al. 1992: 15). Since in Ethiopia today state control of
deforestation is less strict than formerly, erosion in the Ethiopian Highlands
has increased, so that the amount of silt transported by the Nile should have
become greater in recent decades. The seasonality of the Nile discharge due
to the monsoonal rains was the reason why formerly the Nile run-off at
Aswan in September was usually about thirteen times as great as in April.
The variability was not only seasonal but annual, corresponding with the high
rainfall variability in Ethiopia. Extreme discharges measured at Aswan were
141.6 billion m3
in 1878/79 (Said 1993: 140) and 34.8 billion m3
in 1983/84
(El-Naggar 1999: 119).
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