in them owe their origin to other causes. A few may be mentioned: the lake country of an appreciable section of Indonesia is the result of displacement of the
earths crust and damming by lava flows that of Java, Bali, NTT, etc. is a result of certain soluble rock condition. There is the result of variations in the deposition of
river alluviums, plus, in part, some warping of the earths crust. Beyond these, there are many other occurrences and possibilities of formation, but the original
generalization, that lakes are most numerous in glaciated regions, especially those of most recent glaciation, is not invalidated by the exceptions.
3.2 Streams
The lines of moving water which tread their way across the land vary in size from mere rills and brooks to broad, full-flowing rivers. Where land masses
and drainage are large and precipitation plentiful, streams are numerous and permanent; where drainage basins are small and especially where precipitation is
meager, streams are small and intermittent. The presence or lack of streams affects man’s movement and settlements
in a wide variety of ways. Primitive man camped at places along or near streams where water and fish were available and where he had a highway for his raft or
crude boat. Man, primitive or not, has often settled on islands in rivers where the encompassing water provided a barrier against enemies. River junctions have
been strategic points for the control of, and participation in, the trade which moved on the streams. River mouths, making union with the sea, gave access to
ocean routes. When industrial centersarose, the riverbank position provide large quantities of water for rapidly growing urban populations and supplied water for
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power and the processing of materials. In many areas, the fine dark alluviums of river flood plains attracted agricultural populations. In Indonesia westward move-
ment was locally carried and directed by the streams which floated men and their belongings. These are only a few of the ways in which rivers and men have been
and, in many ways, still are related. In regions of humid climate, all except the smallest tributaries are
normally permanently flowing waters. Their volumes may vary with seasonal differences in the amount of water available from precipitation, surface drainage,
and underground drainage. High and low stages represent ordinary behavior, but the streams are always there. In some streams, there may be little difference
between highest and lowest water. This is true particularly where rainfall is of comparatively even distribution throughout the year and where waters are not
partly locked up in the form of ice during the winter season. Variations in flow are significant as part of the physical picture of an area, but they are more significant
in their relations to man and his activities. It is readily apparent that a permanent stream which is in high flood during part of the year and barely flows at another
time is of much less utility than one which maintains a relatively uniform level. Each continent in the world has important rivers and one of them is
Indonesian which has thousands of rivers. All of them have their sources in humid lands, chiefly in rainy, and most of them flow in humid regions throughout their
courses. Streams of this nature, however, they receive sufficient water in the wet lands of their origin to carry them through steppes and deserts. Such streams are
known as exotic streams; at least they are strange, or exotic, in the portions of
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their courses which extend through climatically dry regions. Exotic streams have played a large part in human history. They have supplied relatively abundant
water to regions which otherwise could have supported only small and widely scattered settlements. They have encouraged, even forced, cooperation among
peoples using them particularly in connection with the construction and mainte- nance of extensive irrigation works. Humid-land streams have also played much
the same role because the development of river transportation, the control of floodwaters, the generation of power, and the insurance of sufficient and proper
supplies of domestic and industrial water have demanded cooperative, rather than individual, activity.
Some of the famous and longest river systems in Indonesia are Bengawan Solo in Java, the river of Musi in South Sumatera, ular in North Sumatera,
Tjiliung in Java. Among its conspicuous features are a large number of tributaries, broad and fertile flood plains in its lower portion, and the wide delta which it is
still building out into the Gulf of Sunda. So great water is the volume and so heavy the load of fine materials that the rivers can be detected as a dirty fresh-
water stream for many miles out into the osean, a sort of river in the ocean. Many large and small islands split its discharge area so that it has several mouths instead
of one. Should the Indonesian rivers ever become highly developed, this river probably will be one of the worlds major arteries. It is disproportionate area of
dry climates and with only small drainage basins in the sections which are humid, has few large permanent streams.
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A study of maps which portray the lines of flow of surface waters will indicate many patterns. These are the particular patterns which individual streams
have etched into the land as they have carried on their erosive work. That the patterns are very much a part of the actual geographic expression and not just
features which have been unduly emphasized on maps is illustrated by almost any view which enables the observer to look down upon the land.
The most common stream pattern is the dendritic pattern. The term ‘dendritic’ means tree like, and a stream system with this plan possesses a main
trunk and branches which join it at acute angles. This pattern develops where the running water is cutting rocks, whether loose or consolidated, which are relatively
uniform in their reaction to erosion. Thus, this pattern will occur in a region where streams are running on granite alone, or on a homogeneous sandstone, or wholly
on loose clays, and so on. Sometimes it presents the actual plans of some streams, large and small, which have the dendritic pattern.
Other major stream patterns are the trellis, radial, annular, braided, and glacially deranged. Over the land surface as a whole, they are much less common
than the dendritic pattern, but in areas where they do occur, they are just as observable and significant. The trellis pattern is comprised of relatively straight
lines which join each other at right angles. This pattern occurs where there is a definite banding of the rocks or a pattern of structural weakness in the earths
crust. The radial pattern is found where there is a centrally located area of higher land from which the streams flow out in all directions like spokes from the
hub of a wheel. It also occurs in areas where there is a central low section and
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streams flow in from all, or many, directions. The annular, or ring, pattern occurs most frequently as a result of the erosion of structural domes. Its plan reflects rock
controls which are made operative as soon as the domes have passed the initial stage in their dissection. In a sense, the annular pattern is a curved or bent trellis
pattern. Thebraided pattern, characteristic of streams which are overloaded and have hence dropped materials to clog their former channels, is one of many
joining and rejoining lines. It indicates, better than words, the nature of this pattern. The glacially deranged pattern will be discussed in the next pages, which
includes mention of continental and valley glaciation. Stream patterns are important in many ways. They provide part of the physical plan of a countryside
and they affect the distribution of other physical features. One example is seen in the streams of Bengawan Solo, Musi, etc. Their patterns largely dendritic and so
are the patterns of accompanying flood plains. Water is an abundant in the flood-plain soils and trees able to maintain themselves there. Thus, fin and lines of
trees stand out in dendritic pattern and in sharp contrast to the drier grassy interstream areas. In the ridge-and-valley region of Namo Karang the stream
pattern is trellised and this is the key to distribution of the richer bottomland soils, as well asto the location of those types of natural vegetation which require more
moisture than do the types on the ridges. These only two examples, chosen more or less at random, but they serve to illustrate some of the relationships between
stream patterns to the other natural features. When man comes to travel across the land and to inhabit and use it, stream
patterns; reflected in still other fashions. In the river of Namo Karang, the stream
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pattern is dendritic a many of the villages. It might described as a broken dendritic pattern. The best cornlands are found on the fertile, recent luvium which borders
the stream channels hence the pattern of corn distribution, at least of heavy corn fields, is the same as that the streams. An annular pattern is characteristic of much
of the drainage system of the big hills and the pattern of ranch large follows in strong correspondence. In a large part of Kabupaten Karo, chiefly along the bank
of the river Namo Karang the stream pattern is trellis and the individual parts of the pattern of the positions of the more level lands. These are the lands of densest
settlement for that portion of the state and the population pattern there is essentially trellised.
These are both friend and enemy to man: friend in that they serve so many of
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his needs; enemy in that they go on rampages of destruction or change their courses and thus confuse property limits and political boundaries, or become
polluted and carry filth and disease. The problem of high water is acute in densely populated regions,
especially where the presence of fertile flood plains and strategic trade and manufacturing foci haslured large populations not only into the lower areas but to
the very edge of the low-water channels. It has been said that the problem is not so much to keep the rivers away from the people as to keep the people out of the
rivers. The magnitude of the problem is partly indicated by the fact that one serious floodon the river that may take scores of lives and cause hundreds of
millions of money in damage.
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The control of river waters to the point of preventing serious floods is neither easy nor inexpensive. Normally it requires careful study and artificial
controls of entire drainage basins from uppermost tributaries to stream mouths and the costs run into millions of dollars. Also, it requires the cooperation of many
agencies and of the public as a whole. Yet it may be cheaper to pay for proper controls than to pay the bills for flood damage, particularly if man continues to
crowd the rivers. Stream control itself is only part of the price man pays for cutting away the forests, breaking the sod of grasslands, running cultivation
furrows up and down the slope instead of aligning them with the contours, and settling in the natural drainways. Remedies lie in reforestation, re-grassing,
contour plowing, strip cropping, construction of large and small damsin general, in wise land-use policies operating throughout entire drainage areas, including
suitable adjustments in the use of areas of flood hazard. There is always a certain amount of erosion under perfectly normal con-
ditions, but it is seldom, except in dry regions, that normal erosion causes any widespread difficulties. It is when natural balances are upset and waters speed
unchecked that erosion rises far above normal, and land, soils, and the works of man are then destroyed. It may be possible to rebuild rather quickly the works of
man, whether bridges, highways, or homes, but destroyed soils cannot be replaced for many generations and, in most instances, they are gone for all time.
In regions where water is naturally scarce or in humid areas where de- mands on surface and ground waters are especially heavy, there arise many
conflicts over rights to water. The majority of such conflicts revolve around
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.stream water. In the old days, the disputes were normally settled by force; today they are settled in court and in terms of laws and procedures which have be-
come vciy complicated. It is not unusual forlitigation of a given dispute to continue for several years, or even for decades. Problems of water rights are
particularly complicated in connection with streams which flow through two or more states or in more than one country.
Countless streams formerly clean and attractive have already been polluted by man. This results not merely from increased loads of sediment coming from
man-induced erosion of the land, but also from dumping sewage, trash, and industrial wastes into the nearest convenient stream. The problem has become so
serious and widespread that laws to prevent pollution of streams have been adopted in many regions. Such laws are, however, too few in number, and they
are honored more in the breach than in the practice. Until industrial wastes and domestic sewage are properly treated, far too many of our streams will continue to
resemble moving cesspools. Some of the dangers already noted apply to waters within the earth as well as to those on the surface. The destruction of natural
Asia has more than its share of hills, just as it has more than its share of mountains. The hills of Asia extend from near the equator to the Arctic Ocean and
from the Pacific to the far interior. In a broad sense, they form a ring, only slightly broken around the mountain and plateau core of the mountains of Sibayak and
Sinabung. Because of their great extent, both latitudinally and longitudinally, they present many different aspects and degrees of habitability. Some are bleak
tundras, others are part of extensive northern forests, others practically barren
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deserts, and still others savannas and tropical forests. In general, the warmer and wetter ones, such as the rolling hills of peninsular India and the knobby hill lands
of around Namo Karang river. Those which are dry or wet support only sparse populations. In eastern and southern Asia, where most of the plains are crowded
with people, the hilly regions have been populated much more than they would have been if the plains with their resources had not been used completely. Hill
It has been noted that there are different types of mountains, plains, and plateaus. The same is true of hills: they, too, possess individuality. While such
regions as foreign country are both hilly, the hills differ sufficiently in shape and arrangement to provide a different cast to the particular surface configuration,
even before we consider the changes brought about by their differing utilization by man.
In some sections of the earth, the form and pattern of the hills reflect direct and strong bedrock control. Forexample, much of the hill country of Indonesia is
underlain by strongly folded layers of sedimentary rocks whose axes have a pro- nounced northeast-southwest trend. As weathering and erosion have worked on
these materials, the hard-rock portions have produced ridges and the soft-rock portions have become narrow lowlands. The result is a hill country comprised of
nearly parallel ridges and valleys with a northeast-southwest arrangement—the hill country resembles a series of huge marching waves. In an area of this sort,
the pattern of land use is belted—strips of agricultural land occupy the valleys and strips of forest, the ridges. Travel is easy in the valleys, but difficult across the
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ridges; only where streams have cut narrow gaps, or passes, through the ridges is travel easy from one valley to another.
The shapes of the Namo Karang river is in the condition of valey, it is a long valley. At the bank of the river people can not find shops, restaurant or
hotels. Public transportation also can not be found to the river of Namo Karang. So in order to make Namo Karang is a better tourism object of course these things
are needed to be established. The tourists find it very difficult to get changes in order to go to swim and so to buy food for their meals. When the sun set they are
afraid to keep staying because there is no electricity, therefore they or the visitors eed to go back home as soon as the sun set.
There is no hotel or any type of house to stay in, so they have to go to the capital city of Kabupaten Karo, Kabanjahe or Berastagi to find restaurant and
hotel. So these important things are very crucial to make the river of Namo Karang be better for tourism object and be able to attract tourists.
For the tourists who do not own their own cars or motorcycles they need to hire a taxi or rent car for their transportation in Berastagi or Kabanjahe. The
weather along the river is very fresh because it is surrounded by forest which has many big wild trees. The water of the river is very fresh. It is not cold and warm.
It is good for swimming. The villagers around the river usually drink the water of the river without boiling. They drink the water directly without any kind of
process. For the visitors who visit the river of Namo Karang, they may get some
fresh fish over there to be fried or grill. They may buy the fish from the villagers
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or sometimes the guests ask them to do cocking for them, but if the travellers take along with them the fish or some fresh meet to be grilled or fried they can do it by
themselves.
3.3 Hills
