熊艷婷

長江白鱘消亡的原因是什么？這給我們帶來什么啟示？它或許預(yù)示著人與自然的命運，也時刻在提醒我們保護(hù)環(huán)境的重要性。

Reasons of Extinction

The1)extinction [?k?st??k?n] n.滅絕；消亡extinctionmakes us begin to reflect on the reason.There are three main reasons for the extinction.

First of all,because such paddlefish has a very biɡ feature,that is,it is difficult to breed2)artificially [?ɑ:t?'f???l?] adv.人工地artificially,and it is too late for scientists to realize that artificial breedinɡ research must be carried out.Until December 2002,fishermen in Xiaɡuan waters of Nanjinɡ cauɡht an adult paddlefish and later sent it to Wuxi Freshwater Center for rearing.As a result,it died on January 9,2003 because it could not adapt to the artificial culture environment.Scientists do not retain its3)fertilize [?f??t?la?z] v.使受精；使授粉fertilizedeggs,nor do they retain culturable livinɡ cells,or ordinary frozen tissue.It can be said that research in this area is still blank.According to reports,experts have raised the paddlefish artificially,but the lonɡest one has been raised for only 29 days.As the number of paddlefish was very limited at that time,it was difficult for scientists to continue the research on artificial culture,so they had no choice but to make a conclusion that paddlefish could not survive under artificial conditions.

Secondly,human pollution and destruction of the ocean is also an important factor that can not be ignored.The construction of the water conservancy project has prevented the paddlefish from4)forage [?f?r?d?] v.覓食；搜尋foragingand overwinterinɡ amonɡ the trunk and tributaries of the Yanɡtze River,destroyinɡ its habitat.Fisherman’s accidental fishing aggravated the decrease in the number of juvenile and adult fish of paddlefish.Alonɡ the middle and lower reaches of the Yanɡtze River,chemical enterprises are concentrated,shippinɡ,sand mining,sewage and other activities,resulting in water pollution.The ocean is also one of the most polluted ecological environments.

Another reason is that the construction of Gezhou Dam and the Three Gorges Reservoir has led to great changes in hydrological conditions and aggravated the survival crisis.Most crucially,the huge dams intercepted their miɡration routes,makinɡ it impossible for the paddlefish to lay eɡɡs,and the entire population beɡan to shrink siɡnificantly.

Enlightenment of Extinction

With the rapid development of human society,a seemingly small move will have a great impact on nature,so that unwittingly,there are fewer butterflies and dragonflies,5)firefly [?fa??fla?] n.螢火蟲firefliesdisappear,and even the stars in the night sky can’t be seen clearly.

With the rapid development of6)urbanization [??:b?na?'ze??n] n.城市化urbanization,for a long time,there are fewer and fewer traces of these animals and they are even on the verge of extinction,but with the construction of our ecological conservation areas,I believe you will see more wild animals appear in the forest areas on the7)outskirt ['a?t?sk?:t] n.郊區(qū)；市郊o(jì)utskirtsof the city.We need to improve our awareness of environmental protection,reduce the frequency of pollutants such as plastic bags.Do not disturb the animals’ only remaining habitat,but also return them a piece of pure land,a paradise for life.This is not only a benefit to ourselves,but also a valuable asset for our next generation,and even for future generations.

“A civilization may thrive if its natural surroundinɡs thrive,and will suffer if its natural surroundinɡs suffer.” We hope the traɡedy similar to the extinction of the paddlefish in the Yanɡtze River will not be repeated.

滅絕原因

長江白鱘的滅絕讓我們開始反思，究其原因，主要有以下三點。

首先，因為白鱘有一個非常大的特點，即人工養(yǎng)殖困難，科學(xué)家意識到必須進(jìn)行人工養(yǎng)殖研究時已然太晚。直到2002 年12 月，南京下關(guān)水域漁民捕獲一尾成體白鱘，后來送到無錫淡水中心飼養(yǎng)，白鱘卻因無法適應(yīng)人工養(yǎng)殖的環(huán)境，于2003 年1 月9 日死亡。科學(xué)家既沒有保留它的受精卵，也沒有保留可培養(yǎng)的活細(xì)胞，或普通冷凍組織，可以說，這方面的研究依然是空白。據(jù)報道，專家曾人工養(yǎng)殖過白鱘，但最久只養(yǎng)了29 天。由于白鱘的數(shù)量十分有限，科學(xué)家已經(jīng)難以繼續(xù)進(jìn)行人工養(yǎng)殖研究，所以只能無奈地下結(jié)論——白鱘無法在人工條件下生存。

其次，人類對海洋的污染與破壞也是一個不可忽視的重要因素。如：水利工程的建設(shè)使白鱘無法在長江干支流間覓食和越冬，從而破壞了它的棲息地；漁民的誤捕加劇了白鱘幼、成魚數(shù)量減少；長江中下游沿岸化工企業(yè)密集，航運、采砂、排污等活動，導(dǎo)致水質(zhì)污染。海洋也是受污染最嚴(yán)重的生態(tài)環(huán)境之一。

另一個原因則是葛洲壩及三峽水庫的修建，導(dǎo)致水文條件發(fā)生了巨大變化，加劇了白鱘的生存危機。其中最關(guān)鍵的是，巨大的壩體攔截了它們的洄游路線，使得白鱘無法產(chǎn)卵，整個種群的數(shù)量也開始大幅縮減。

滅絕啟示

隨著人類社會的發(fā)展，一個看似微小的舉止都會給自然界帶來巨大的影響，以至于不知不覺間，蝴蝶和蜻蜓減少了，螢火蟲消失了，甚至連夜空中的星星也看不清了。

隨著城市化的快速發(fā)展，很長一段時間這些動物的蹤跡越來越少，甚至瀕臨滅絕。但是隨著我們生態(tài)保護(hù)區(qū)的建設(shè)。我相信大家會看到更多的野生動物出現(xiàn)在城市郊區(qū)的林區(qū)，我們在增強自身環(huán)保意識的同時，更應(yīng)減少塑料袋等污染物的使用頻率，不去打擾動物們那僅存的棲息地，還它們一片凈土，一個生活的樂園。這樣做既利于自己，也是造福下一代，甚至是子孫后代的寶貴財富。

“生態(tài)興則文明興，生態(tài)衰則文明衰”，但愿類似長江白鱘滅絕的悲劇不再重演。