Centre Democrat. [volume] (Bellefonte, Pa.) 1848-1989, 1882-01-26
Recent Changes in the Earth's Surface.

Recent Changes In the Earth's Surface.
According to Lombardini, the Po
now transports nearly three times as
much sediment as formerly, the in.
crease being chiefly due to the destruc-
tion of the forests and the consequent
increased denudation of the Alps.
French engineers estimate that the
delta Of the Rhone has advanced at
rate far greater than il did previous to
the cultivation OF its valley. In the
Eastern United States, wherever a m 5un
tain slope has been stripped, incipient
ravines quickly form and enlarge with
such rapidity as to excite the attention
Of geologists. This is especially tho
case with the sandy soils of Maryland,
Georgia and Alabama, previously
covered with pine forests.
The black earth OF Russia, one OF the
chief sources OF the agricultural wealth
of the empire, is quickly cut up into
huge ravines, and the finest soil in En-
rope is being rapidly carried away to
increase the deltas of the Volga and the
Don. and to slit up the sea of Azof.
During the great floods of 1866 and
1868 in France and Switzerland, the
wooded soils alone escaped from being
washed away. The immunity OF the
provinces Of Brescia and Bergamo from
damage by the great foods Of 1872 was
chiefly due to forest improvements.
During ten years the department of the
Lower Alps lost G1, 900 acres Of cult
waited soil from the effects Of torrents
and the clearing OF the forests OF Ar.
deche has resulted in the covering up
Of 10000 acres of good land with barren
sand and gravel.
II is thought by many that vegetation
elevates tho surface as much as water
depresses it. This, however, can only
be the case when natural vegetation is
suffered to decay on tho ground in
which it grew. In the case OF cultivs-
ted crops, which only partly return to
the soil, this elevation of the surface
cannot take place, and it's compensa-
ting effect being lost, denudation is
relatively greater from this cause alone.
Hence, it appears that one effect of
mans Influence, by laying bare large
tracts OF land for cultivation, has been
TO largely increase the erosion OF the
surface. In some instances, however,
the action OF man has been to check the
natural transport of sediment. This
especially has been done in the case of
shifting sand-dunes and encroachments
of the sea. Along that part OF the
French coast which extends from the
Gironde to the Adour, the sea throws up
annually ,245, 900 cubic meters Of sand,
which the wind heaps up into hills and
carries inland, overwhelming villages
and converting streams into marshy
pools. The annual progress Of these
sand hills was so great that in many
R9&ssS VI ofchabho bhs toHn Va chAAhuegH
above q sea Of sand alone marked the
site Of buried villages. The amount of
duneland in Western Europe alone has
been estimated to cover more than
1000. 900 acres, and still larger deposits
exist in parts OF Asia, Africa and Amer
ica. The destruction caused by these
shifting sands has. from an early date,
attracted the attention of governments;
and the result has been TO check their
ravages by careful planting. Thus has
mans ingenuity been successfully op-
posed to the action of the agencies
which have caused those endless wastes
OF drifting sands In Poland, Peru and the
United States; and to the devastation
which has resulted In the formation of
the iandcs Of Gascony, sologno and
Brenne, and the CAMPING sands Of Bel
gium.- Chamber Journal.