Waterfall - Taki (English spelling)

Japanese: 滝 - たき（英語表記）water fall

This refers to the state in which river water falls almost vertically. It is also called a waterfall. There are various types, from water that leaves the riverbed and falls, to water that does not leave the riverbed but flows down an extremely steeply sloping riverbed creating white foam, to water that falls in one or several stages. In any case, a waterfall is formed as a result of a very sudden interruption of the riverbed. The point where the water falls is quite wide and deep, and is called a waterfall basin. There, the flowing water forms a whirlpool, and the rolling pebbles and sand that are stirred up by the whirlpool erode the surrounding rocks, and the huge angular gravel that falls into it turns into rounded gravel.

[Masami Ichikawa]

Cause

The geomorphological origins of the waterfall are as follows:

(1) When hard rocks cross the riverbed, the river channel resists erosion and forms steep cliffs, causing the flowing water to turn into waterfalls. Examples of this are Niagara Falls on the border between the United States and Canada, Kaieteur Falls in Guyana, South America, and Gibbon Falls in Yellowstone National Park in the United States.

(2) They flow along the steep edges of plateaus, such as the Augrabies Falls on the Orange River across the African plateau in Namibia.

(3) When a river flows down a fault cliff. The Zambezi Falls in Mozambique, Africa, is a good example of this, and can be seen in various places in Japan as well.

(4) In glacial regions, the main valley glacier creates a deep U-shaped valley with its powerful erosion force, while the smaller tributary valley glaciers form shallow U-shaped valleys, and the confluence of these glaciers forms a hanging valley that creates a waterfall. Yosemite Falls in California, USA, and the hanging valley of the Lauterbrunnen Valley in Switzerland are good examples.

(5) They form on the edges of sea cliffs, as seen on the Devon coast at Litter Oat in the Hartland area in the central north of the Cornish peninsula in southwest England.

(6) They are formed when volcanic lava flows or landslide materials are blocked, and examples of this can be seen in various places, such as Kegon Falls in Nikko, Japan.

[Masami Ichikawa]

The disappearance of the waterfall

Waterfalls are generally characteristic of young rivers, but as erosion progresses and the river approaches the equilibrium state of a mature river, the waterfalls disappear and the riverbed becomes smooth. Waterfalls retreat and eventually disappear, but the rate of retreat varies depending on the hardness of the layer that created the waterfall, the volume of water, and the height of the waterfall. Niagara Falls has retreated 11 kilometers to date, at an average rate of 0.7 to 1.4 meters per year. Kegon Falls is thought to have originally been located just downstream from Irohazaka, but it has retreated about 2 kilometers to date. Evidence of its retreat can be seen throughout Kegon Gorge.

[Masami Ichikawa]

Waterfalls of the World

From a global perspective, there are three types of large waterfalls: (1) those on the edges of plateaus or at the points where the plateaus are dissected, (2) those at the boundary between the resistant crystalline rocks of the interior of continents and the soft sedimentary rocks of coastal areas, and (3) those in high mountain areas that were primarily eroded by glacial erosion during the last glacial period.

[Masami Ichikawa]

Cultural history

Few cultures have given waterfalls a specific meaning. In densely populated areas, either large waterfalls did not exist due to precipitation or topographical conditions, or if there were any, they had disappeared due to long-term vegetation destruction and reduced flow. Large waterfalls were limited to dangerous places that were difficult for humans to access and were rarely known by the surrounding residents, and waterfalls that were easily visible to humans were often only dangerous obstacles to shipping and fishing. Even in many advanced cultures located in dry plains, small waterfalls were merely appreciated as rare scenery, and the East Asian painting tradition, which considered special meaning and elevated waterfalls to an element of artistic expression, is probably an exception. One of the earliest examples is the waterfall depicted in "Kizōsōgakuzu" (Elephant Riding and Playing Music) in the Shosoin Repository, one of the few surviving examples of painting from the Heian period (1603-1868), and since then, waterfalls have been an element that cannot be ignored in East Asian paintings (especially landscape paintings). The background to this is thought to be the geographical conditions of East Asia, where there are many waterfalls, as well as the fact that the Abhidharma-Kosha, which was written in northwest India in the 5th century and translated into Chinese in the mid-7th century, becoming one of the fundamental documents of East Asian Buddhist philosophy, translated the whirlpool of earthly desires that washes people away as a "violent current," which gave rise to an association with a waterfall (bakuryu, a waterfall-like current), and thus gave rise to the attachment of a special religious meaning to waterfalls and the physical experience of being at a waterfall.

[Akira Sasaki]

Folklore and legends

Japan has many valleys, so large and small waterfalls can be found all over the country. Some famous scenic spots include Kegon Falls in Nikko, Nachi Falls in Kumano, and Nunobiki Falls in Kobe. Some waterfalls are linked to the faith of shrines and temples, and some people practice pilgrimage by being hit by the falls out of their faith. There are many legends about waterfalls. In Nagaizumi Town, Sunto County, Shizuoka Prefecture, there is Ayutsubonotaki Falls. Long ago, a rich man in that area had a daughter named Kamezuru. When Minamoto no Yoritomo was holding a hunting party at Mt. Fuji, he fell in love with the girl and desired to marry her, but she refused and threw herself into the Ayutsubonotaki Falls. There are many similar stories of people throwing themselves into waterfalls all over the country. There is also Nihogataki Falls in the Nagaomote village of Nishimeya Village, Nakatsugaru County, Aomori Prefecture. This waterfall freezes over in the coldest of winters, so long ago the feudal lord would send envoys to inspect the size and shape of the frozen ice and report back. This was used to predict the year's harvest, and so this waterfall was also called Seken Taki. There is a waterfall called Ansan no Taki in the Oyodo River in Yoshino County, Nara Prefecture. It has long been said that if a person suffering from difficult childbirth is hit by this waterfall, they will have an easy birth.

There are examples of people praying to waterfalls for rain. At Itokawa Falls in Itokawa Village, Arida County, Wakayama Prefecture (now Yuasa Town), a person who has purified himself enters the pool at the waterfall to pray for rain. It is said that if he sees white fish, rain will come, but if he sees black fish, it will not. Himon Falls in Kanda Village, Naga County, Wakayama Prefecture (now Kinokawa City) has long been known as a place to pray for rain. One way to pray for rain is to throw stones or waste into the pool to anger the god of the waterfall and make it rain.

[Oto Tokihiko]

"Japanese Waterfalls 1: 661 Waterfalls in Eastern Japan" (2004, Yama-to-Keikoku-sha) with photos and text by Kitanaka Yasufumi; "Japanese Waterfalls Guide 4000" (2005, Toho-shuppan) with photos and commentary by Kida Kaoru; "Japan: The Kingdom of Waterfalls" (2007, Ei-shuppan) by Kitanaka Yasufumi

[References] | Kegon Falls | Niagara Falls | Nachi Falls| Nunobiki Falls

Niagara Falls (American Falls)
View from the Canadian side. Drop of 51m, width of 305m. Niagara Falls, USA ©Masashi Tanaka ">

Niagara Falls (American Falls)

Yosemite Falls
It is located in Yosemite Valley, the center of Yosemite National Park in western North America. Part of the World Heritage Site "Yosemite National Park" (registered in 1984 in the United States) California, USA ©Masashi Tanaka ">

Yosemite Falls

Iguazu Falls
A large waterfall on the Iguazu River, a tributary of the Paraná River. Several waterfalls flow down the 2,700m-wide horseshoe-shaped terrain. The photo is from the Argentine side. Part of the World Heritage Site "Iguazu National Park" (Argentina/Brazil, registered in 1984/1986) Argentina/Brazil ©Shogakukan ">

Iguazu Falls

Kegon Falls
A 97m waterfall on the Daiya River. It is counted as one of the "Three Famous Waterfalls of Nikko" along with Kirifuri Falls and Uramitaki Falls. It is said to have been discovered by Shodo Shonin, the founder of Nikko, and named after the Avatamsaka Sutra. It is one of the most representative landscapes of Nikko National Park. Nationally designated Place of Scenic Beauty Nikko City, Tochigi Prefecture ©Shogakukan ">

Kegon Falls

Nachi Falls
Yoshino-Kumano National Park area. Nationally designated scenic spot. Part of the World Heritage Site "Sacred Sites and Pilgrimage Routes in the Kii Mountain Range" (registered in 2004). Nachikatsuura Town, Higashimuro District, Wakayama Prefecture ©Wakayama Prefecture ">

Nachi Falls

Nunobiki Falls
The waterfall above is Otaki, and the waterfall below is Meotodaki. Kobe City, Hyogo Prefecture © Kobe International Tourism and Convention Association

Nunobiki Falls

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

Japanese:

川の水がほぼ垂直に落下する状態をいう。瀑布(ばくふ)ともいう。流水が河床を離れて落下するものから、河床からは離れないがきわめて急傾斜な河床を白い泡をたてて流下するもの、一段から数段に分かれて落下するものなどさまざまである。いずれにしても、河床が著しく急激に中断されている結果として滝ができる。滝の落下点は相当の広さと深さを有し、これを滝壺(たきつぼ)という。そこでは流水が渦流となり、転動する小石や渦流とともに巻き上げられる砂によって周辺の岩石が削られ、また中に落下している巨大な角礫(かくれき)が円礫に変わる。

［市川正巳］

成因

滝の地形学的成因をみると次のとおりである。

(1)河床を横切る硬い岩石がある場合は、その部分で河道が侵食に抵抗して急な崖(がけ)となり、流水は滝となる。たとえば、アメリカとカナダの国境にあるナイアガラ滝、南米ガイアナのカイエトゥール滝やアメリカのイエローストーン国立公園のギボン滝などがその例である。

(2)高原の急な縁辺部を流れる場合。たとえば、ナミビアのアフリカ高原を横切るオレンジ川がオーグラビース滝となる。

(3)流路が断層崖(がい)を下る場合。アフリカのモザンビークのザンベジ滝はその好例で、日本でも各地にみられる。

(4)氷河地域で、本流の谷氷河が強大な侵食力で深いU字谷をつくり、支流の小さい谷氷河は浅いU字谷を形成するため、その合流点は懸谷となり滝をつくる。アメリカのカリフォルニア州にあるヨセミテ滝、スイスのラウテルブルンネン谷の懸谷はその好例である。

(5)海食崖の縁辺部にできる場合で、イギリスの南西コーンウォール半島中北部ハートランドのリッター・オーターにあるデボン海岸にみられる。

(6)火山の溶岩流や山崩れ物質によってせき止められてできる場合で、日本の日光の華厳滝(けごんのたき)など各地にその例がある。

［市川正巳］

滝の消失

一般に滝は幼年期の河川の特徴であるが、侵食が進んで壮年期の平衡河川の状態に近づくと、滝は消失して平滑な河床となる。このように滝は後退してやがては消失するのであるが、その後退速度は、造滝層の硬さの度合いや水量、滝の落差などによって異なる。ナイアガラ滝では、現在まで11キロメートル後退し、年平均0.7～1.4メートルの割合で後退している。華厳滝の最初の位置は「いろは坂」のすぐ下流地点と思われるが、それが現在までに約2キロメートル後退している。その後退していった証拠は華厳渓谷の中の随所でみることができる。

［市川正巳］

世界の滝

世界的な観点からみると、次の三つの地域に大規模な滝がかかっている。すなわち、(1)高原の縁辺部にかかる滝、もしくはその高原を開析する地点にかかる滝。(2)大陸内部の抵抗性の岩石である結晶質岩と海岸地域の軟らかい堆積(たいせき)岩の境界地点にできる。(3)主として最後の氷期の氷食によって削られた高山地域にできる、などである。

［市川正巳］

文化史

滝に特定の意味を与えた文化は少ない。居住人口の多い地域では、降水、地形条件から大きな滝がないか、あっても長期間の植生破壊、流量減少により消滅したかのいずれかで、大きな滝は人間の近づきがたい危険な場所に限られて、周辺住民に知られることが少なく、人間の目に触れやすい滝は舟運・漁業の危険な障害にすぎないことが多かった。乾燥した平野部に立地した多くの高度文化でも、小さな滝を珍しい景観として観賞するにとどまり、特別な意味を考えて滝を美術的表現の一要素にまで高めた東アジアの絵画的伝統は例外的存在だろう。盛唐絵画の数少ない残存例の一つである正倉院の『騎象奏楽図(きぞうそうがくず)』に描かれた滝をもっとも早い例の一つとして、それ以降の東アジア絵画（とくに山水図）では、滝が無視できない要素であった。その背景には、滝の多い東アジアの地学的条件に加え、5世紀に北西インドで成立し、7世紀中葉に漢訳されて東アジア仏教哲学の基本文献の一つとなった『阿毘達磨倶舎(あびだるまぐしゃ)論』で人間を押し流す煩悩の渦を「暴流(ぼる)」と訳し、滝（瀑流(ばくりゅう)）との連想が生じ、滝および滝での肉体的経験に特別な宗教的意味を付するに至ったことがあったと考えられる。

［佐々木明］

民俗・伝説

日本には渓谷が多いので大小の滝が各地にみられる。名勝地として著名なものに日光の華厳滝、熊野の那智(なち)滝、神戸の布引(ぬのびき)滝などがある。滝には社寺の信仰と結び付いたものがあり、信仰心から滝に打たれて行(ぎょう)を積む者がある。滝についてはいろいろの伝説がある。静岡県駿東(すんとう)郡長泉(ながいずみ)町に鮎壺滝(あゆつぼのたき)というのがある。昔その地の長者に亀鶴という娘があった。源頼朝(よりとも)が富士の巻狩を行ったときこの娘を見そめて所望したが、娘はこれを拒み鮎壺滝に身を投げてしまったという。滝に身を投げる話は全国的に類例が多い。また青森県中津軽郡西目屋(にしめや)村長面(ながおもて)集落に新穂ヶ滝(におがたき)というのがある。寒中にはこの滝が氷結するので、昔は藩主が使臣を遣わして、その結氷の大小・形状などを視察させて報告させた。それによってその年の豊凶を卜(ぼく)したので、この滝を世の中滝ともいったという。奈良県吉野郡の大淀(おおよど)川の流れに安産の滝というのがある。昔から難産に苦しむ者がこの滝に打たれると安産になるといわれている。

　滝に雨乞(ご)いをする例がある。和歌山県有田(ありだ)郡糸川村（現、湯浅町）の糸川滝では、潔斎した人が滝壺に入って雨乞いをする。そのとき白魚をみれば降雨があり、黒魚ならば降らないという。同県那賀(なが)郡神田村（現、紀の川市）の秘文(ひもん)滝は、昔から雨乞いをする場所として知られている。雨乞いのなかには、滝壺に石や汚物を投入して滝の神を怒らせて雨を降らすというものもある。

［大藤時彦］

『北中康文写真・文『日本の滝1　東日本661滝』（2004・山と渓谷社）』▽『木田薫写真・解説『日本滝名鑑4000』（2005・東方出版）』▽『北中康文著『滝王国ニッポン』（2007・枻出版社）』

[参照項目] | 華厳滝 | ナイアガラ滝 | 那智滝 | 布引滝

ナイアガラ滝（アメリカ滝）

ヨセミテ滝

イグアス滝
パラナ川の支流イグアス川にかかる大瀑布。幅2700mの馬蹄形の地形にいくつもの滝が流れ落ちる。写真はアルゼンチン側。世界自然遺産「イグアス国立公園」の一部（アルゼンチン／ブラジル・1984／1986年登録）　アルゼンチン／ブラジル©Shogakukan">

イグアス滝

華厳滝
大谷川にかかる高さ97mの滝。霧降滝、裏見滝とともに「日光三名瀑」の一つに数えられる。日光開山勝道上人の発見と伝え、命名は『華厳経』によるという。日光国立公園を代表する景観の一つである。国指定名勝　栃木県日光市©Shogakukan">

華厳滝

那智滝

布引滝

出典　小学館　日本大百科全書(ニッポニカ)日本大百科全書(ニッポニカ)について　情報 | 凡例