. Elementary physical geography . row is com-pletely overrunning this country. Insect pests and diseasesare also spread, and these attack not merely man, but alsothe plants and animals. However, it is in the destruction of life that the mostbaneful influence of man is noticed. Animals of nearly allkinds, particularly some of the largest, are disappearingbefore his advance. Several species have been entirely ex-terminated, and some, such as the bison, which was formerlyso abundant, have been so reduced in numbers that they arealmost exterminated. By the destruction of birds, the num-ber of inse
. Elementary physical geography . row is com-pletely overrunning this country. Insect pests and diseasesare also spread, and these attack not merely man, but alsothe plants and animals. However, it is in the destruction of life that the mostbaneful influence of man is noticed. Animals of nearly allkinds, particularly some of the largest, are disappearingbefore his advance. Several species have been entirely ex-terminated, and some, such as the bison, which was formerlyso abundant, have been so reduced in numbers that they arealmost exterminated. By the destruction of birds, the num-ber of insects has been increased; and so both directly and1 It is estimated that one-tenth of Holland is land reclaimed from the sea. MAN AND NATURE. 409 indirectly the influence of man in this direction has beenharmful. Man and the Forest. — Probably the most important singleinfluence of man comes from his habit of destroying theforest (Fig. 263). In many ways the forest covering isimportant. It protects the soil from being washed away,. Fig. 263. A part of the Adirondack forest. (Copyrighted, 1888, hy S. R. Stoddard, Glens Falls, ) and when it is removed, and the soil turned by the plow,both weathering and the removal of the loose materials areincreased. In some places, notably in France, the mountainsides, from which the forests have been stripped, have beentransformed to barren wastes of rock because of the re-moval of the soil by the rain. In other places, the soil has 410 PHYSICAL GEOGRAPHY. been so gullied that it is unfit for cultivation. A part ofMississippi lias been transformed to a barren waste of clay,the features of which resemble those of the Bad Lands ofSouth Dakota (Plate 21). The effect of the absence offorests is well illustrated in the arid lands, where the forestcovering is absent because of natural climatic every rain gullies the land; and on the steeply slopinghillsides, the removal of the soil by rain and wind action hasexposed the bare rock
Size: 1827px × 1368px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthortarrralphsralphstockm, bookcentury1900, bookdecade1900
