Anonymous
Anonymous asked in 科學其他:科學 · 2 decades ago

探討亞馬遜叢林...20點

1。亞馬遜叢林物種繁多。此區動植物會以哪些方式來增加捕食機會或減少被捕時?

2。亞馬遜叢林的動物常有吃食泥漿的習性。原因為何?

3。亞馬遜叢林的行軍蟻在地被層中是一種殘忍的掠食者。試問他在此區的生態貢獻為何?

4。亞馬遜叢林年雨量多少?為何此區喬木高度幾乎都超過15公尺以上?

5。亞馬遜叢林的樹冠層溫度高且水分蒸發量極大。對於生活於樹冠層的動物而言該如何適應缺水環境?

6。樹冠層的附生植物。在沒有土壤的環境下如何獲得含氮元素的養分?

3 Answers

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  • Anonymous
    2 decades ago
    Favorite Answer

    Amazon Rainforest

    From Wikipedia, the free encyclopedia.

    A river in the Amazon rainforest

    The Amazon is a rainforest in South America. It encompasses 1.2 billion acres (7 million km²), with parts located within nine nations: Brazil (with 60% of the rainforest), Colombia, Peru, Venezuela, Ecuador, Bolivia, Guyana, Suriname and French Guiana. This forest represents over half of the planet's remaining rainforests. States or departments in four nations bear the name Amazonas for the Amazon.

    The Amazon Basin

    The forest lies in a basin drained largely by the Amazon River, with 1100 tributaries. This basin was formed in the Palaeozoic period, between 500 and 200 million years ago.

    Biodiversity

    Roots in the Amazon rainforest

    The region is home to ~2.5 million insect species, tens of thousands of plants, and some 2000 birds and mammals. The diversity of plant species is the highest on earth with some experts estimating that one square kilometre may contain over 75,000 types of trees and 150,000 species of higher plants. One square kilometre of Amazon rainforest can contain about 90,000 tons of living plants. This constitutes the largest collection of living plants and animal species in the world. One in five of all the birds in the world live in the rainforests of the Amazon. To date, an estimated 438,000 species of plants of economic and social interest have been registered in the region with many more remaining to be discovered or cataloged. (Note: Brazil has one of the most advanced laws to avoid biopiracy, but enforcing it is a problem.)

    Environmentalism

    A river in the Amazon Rainforest

    There has been concern among environmentalists for many years, regarding the deforestation of the region, stemming mainly from the fact that more than one fifth of the Amazon Rainforest has already been destroyed; and much more is threatened. Not only are environmentalists concerned about the loss of biodiversity which will result from the forest's destruction, they are also concerned about the release of the carbon which is held within the trees -- this carbon will accelerate global warming.

    The deforestation of this area in the 1980s was largely considered catastrophic. Yet, in 1996, the Amazon was reported to have shown a 34 per cent increase in deforestation since 1992. A new report by a congressional committee says the Amazon is vanishing at a rate of 52,000 square kilometers (20,000 miles²) a year, over three times the rate for which the last official figures were reported, in 1994.

    Environmentalists commonly stress the fact that there is not only a biological incentive to protecting the rainforest, but also an economic one. One square kilometer in the Peruvian Amazon has been calculated to have a value of $682,000 if intact forest is sustainably harvested for fruits, latex, and timber; $100,000 if clear-cut for commercial timber (not sustainably harvested); or $14,800 if used as cattle pasture.

    The Força Aérea Brasileira has been using EMBRAER R-99 surveillance aircraft, as part of the SIVAM program, in an attempt to halt rainforest molestation. At a conference in July 2004, scientists warned that the rainforest will no longer be able to absorb the millions of tons of greenhouse gases annually, as it usually does, because of the increased pace of rainforest destruction. The large-scale cutting of trees begins a cycle in which farmers burn leftover jungle scrub to replenish the soil, which releases huge amounts of carbon dioxide (200 to 300 million tons in 2003) into the atmosphere, that are in turn absorbed by the rainforest.

    亞馬遜河(大陸官方譯名亞馬孫河)位於南美洲,雖然長度在世界上處於第二位,但流量是世界上最大的,比其他三條大河:尼羅河、密西西比河和長江的流量總和還要大,亞馬遜河的流域面積也是世界上最大的。

    亞馬遜河向大西洋排放的水量達到了每秒18萬4千立方米,相當於全世界所有河流向海洋排放的淡水總量的五分之一,從亞馬遜河口直到肉眼看不到海岸的地方,海洋中的水都不咸,150公里以外海水的含鹽量都相當低。

    亞馬遜河主河道有1.5到12公里寬,從河口向內河有3700公里的航道,海船可以直接到達秘魯的伊基托斯,小一點的船可以繼續航行780公里到達阿庫阿爾角,再小的船還可以繼續上行。

    亞馬遜河流域面積達到6915000平方公里,相當於南美州總面積的40%,從北緯5度伸展到南緯20度,源頭在安第斯山高原中,離太平洋只有很短的距離,經過秘魯和巴西在赤道附近進入大西洋。

    源頭和上游

    流經秘魯城市伊基托斯的亞馬遜河亞馬遜河的源頭最近才正式確定,是在秘魯安第斯山區中一個海拔5597米的山峰叫奈瓦多·米斯米的山峰中的一條小溪。距離秘魯首都利馬大約有160公里,在利馬南部偏西,1971年第一次認定,直到2001年才正式確定,溪水先流入勞里喀恰湖,再進入阿普里馬克河,阿普里馬克河是烏卡亞利河的支流,再與馬臘尼翁河匯合成亞馬遜河主幹流。

    從馬臘尼翁河的支流瓦利亞加河以下,河流就從安第斯山區進入沖積平原,從這裡到秘魯和巴西交界的雅瓦里河,大約有2400公里的距離,河岸低矮,兩岸森林經常被水淹沒,只是偶爾有幾個小山包,亞馬遜河已經進入了亞馬遜熱帶雨林中了。

    亞馬遜雨林

    安第斯山以東,就是亞馬遜熱帶雨林了,這是世界上最大的雨林,具有相當重要的生態學意義,它的生物量足以吸收大量的二氧化碳,今年來保護亞馬遜熱帶雨林已經成為一個重要的論題了,亞馬遜熱帶雨林依靠亞馬遜河流域非常濕潤的氣候,亞馬遜河和她的100多個支流緩慢地流過這片高差非常小的平原,河岸旁的巴西城市馬瑙斯距離大西洋有1600公里,但海拔只有44米。

    這個雨林的生物多樣化相當出色,聚集了250萬種昆蟲,上萬種植物和大約2千種鳥類和哺乳動物,生活著全世界鳥類總數的五分之一。有的專家估計每平方公里內大約有超過75000種的樹木,15萬種高等植物,包括有9萬噸的植物生物量。

    洪水

    亞馬遜河洪水泛濫的衛星圖片季節性的降雨使亞馬遜河和其支流經常泛濫,在雨季河道平均深達40米,寬展到平均38公里,從11月份開始漲水,直到第二年6月份,然後回落到10月份。其支流內格羅河水的漲落和幹流還不在同一時間,雨季是從2月或3月開始,漲到6月開始和主幹流一起回落。另一個支流馬代臘河的漲落要比主流提前兩個月。

    在雨季里,亞馬遜河淹沒了幾十萬平方公里,洪水深度在有些地方比旱季水位最低時高出12到15米,在伊基托斯附近高出6米;在泰弗附近是15米;在奧比多斯附近是11米,在帕臘河是4米。

    下游

    亞馬遜河在有些地方河寬達6到10公里,有的地方,河水分為兩股,中間形成複雜的自然河網,形成許多大小島嶼,比河面高出不到5米,在最窄的地方,如離河口600公里的奧比多斯,河流直有1.6公里寬,但有600米深,這時河水流速達到每小時6至8公里。加拿利亞村在內格羅河和主幹流匯合的大彎道附近,直到下游1000公里地方,和亞馬遜河的河口附近相似,地勢低窪,廣大區域都淹沒在水中,森林只有樹的上半部伸出水面。從內格羅河到馬代臘河河岸低矮,只有巴西城市馬瑙斯附近才有一些起伏的山地,在奧比多斯附近有一個陡峭的懸崖,有20米高,後面是低矮的山地。亞馬遜河下游可能以前是大西洋的一個海峽。

    巴西城市瑪瑙斯附近的亞馬遜河只有不到10%的亞馬遜河河水流入奧比多斯以下的流域,有很少量的水是來自北方山谷奧比多斯以上的流域有5百萬平方公里,以下只有一百萬平方公里,只有上游的20%。這沒有算上緊口河口的支流托坎廷斯河流域的一百萬平方公里。

    在下游興古河對面的北岸有許多平頂的小山,延展大約有240公里。興古河以上的南岸是阿勒格爾山,一路的峭壁約束著亞馬遜河的河岸,直到聖塔侖,然後折向西南,形成另一條支流塔帕若斯河的河谷。

    亞馬遜河河口

    河口

    河口在最寬的入海處大約有330公里,作為最後一條支流托坎廷斯河的下游的帕臘河有60公里寬,在河口帕臘河和亞馬遜河主河道之間有一個幾乎有丹麥一樣大的馬臘若島。

    激浪潮

    從河口向北,直到蓋亞那邊界的160公里,都是沙灘和暗礁,這兒的潮汐叫做激浪潮,水深不足7米,但激浪潮大聲咆哮,以每小時15到25公里的速度衝擊海岸,浪高達1.5到4米,所以亞馬遜河形不成三角洲。,大海迅速地將亞馬遜河攜帶的泥沙捲走。

    水生生物

    亞馬遜河水中生活著多種水生生物,亞馬遜海豚是世界上體形最大的淡水海豚,成體可達2.6米,還有食人魚,它們成群生活,可能攻擊人畜,雖然有許多專家不認為它們這麼可怕,但在1981年在奧比多斯的翻船事故中有300人喪生在它們口中。

    在亞馬遜河流域的淺水中還有水蟒,是世界上最大的蛇,它們大部分時間在水中,只把鼻孔露出水面,但水蟒一般不攻擊漁民。河中還有幾千種魚類、蟹和龜鱉類生活。

    Source(s):
  • Anonymous
    2 decades ago

    真的嗎?這是老師自己出的。

    有些我自己有寫。怕自己錯~

    所以提出來探討一下。謝謝大家!

  • 2 decades ago

    能請問你的問題來源嗎?比如說,它是否是學校作業?

    有些題目的敘述似乎有誤。

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