博茨瓦納野生動物管理部門的官員們說，水中微型水藻產(chǎn)生的毒素導(dǎo)致該國數(shù)百頭大象先前因不明原因死亡。在博茨瓦納境內(nèi)生活的大象數(shù)量占非洲日益減少的大象數(shù)量的三分之一。

The elephants, young and old, had collapsed and died suddenly in large numbers. Experts soon ruled out poaching. After all, no one had tried to hack off the elephants’ tusks. But beyond that lay a mystery.

這些大象，無論老幼，都突然大批倒地死亡。專家們很快就排除了死因是偷獵行為的可能性。畢竟，沒有人試圖砍掉這些大象的象牙。但除此之外，大象的死因是個謎團(tuán)。 

Tests sent to laboratories around the world now appear to have settled the matter. Poisonous natural cyanobacteria is to blame, lurking in the elephants’ watering holes. Those watering holes have now dried up and the elephants have stopped dying.

送往世界多國實(shí)驗(yàn)室的采樣測試結(jié)果看來已經(jīng)解開了大象死因的謎團(tuán)。有毒的天然藍(lán)藻細(xì)菌是罪魁禍?zhǔn)祝{(lán)藻細(xì)菌潛伏在大象飲水的水坑里。那些水坑現(xiàn)在已經(jīng)干涸，大象也繼而停止死亡。

But scientists warn that climate change may be making these incidents, known as toxic blooms, more likely. 

但科學(xué)家們警告說，氣候變化可能使這些被稱為 “有毒水華” 的事件更有可能發(fā)生。

詞匯表

collapsed 倒下了
ruled out 排除了
poaching 偷獵
hack off 砍掉，砍下
tusks 象牙
mystery 謎，謎團(tuán)
settled 解決了
cyanobacteria 藍(lán)藻細(xì)菌
lurking 潛伏著，潛藏著
blooms 水華現(xiàn)象

閱讀理解：請?jiān)谧x完上文后，回答下列問題。

1. True or false? The elephants that had died in Botswana were all young.

2. Why did the experts rule out poaching?

3. Where was cyanobacteria found?

4. According to the scientists, what is the possible connection between climate change and these incidents?

答案

1. True or false? The elephants that had died in Botswana were all young.
False. The elephants, young and old, had collapsed and died suddenly in large numbers.

2. Why did the experts rule out poaching?
Because no one had hacked off the elephants’ tusks. 

3. Where was cyanobacteria found? 
Cyanobacteria was found lurking in the elephants’ watering holes.

4. According to the scientists, what is the possible connection between climate change and these incidents?
Scientists warn that climate change may be making these incidents, known as toxic blooms, more likely.