题干

对藻类的水华生物生长繁殖产生影响。据新华社合肥8月10日电,安徽省巢湖市饮用水源地周边连日来出现明显蓝藻集聚。安徽省环保厅已两次发出蓝藻水华红色预警,这引发了公众对于饮用水安全的担忧。

分析7、8月份巢湖“水华”现象严重的原因。

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答案(点此获取答案解析)

受伏旱影响,7、8月份高温少雨,盛夏用水量增加,导致湖水补给量减少;流入该湖的污染水体所占比重大,水体富营养化加重;7、8月份气温高、光照强,水华生物生长繁殖速度快。

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    What's your opinion on spicy food? Some people cannot handle even the smallest amount of chili(辣椒) in their dinner while others can't get enough of it.       

Scientists have long been puzzled by why some people love chili and others loathe it. Plenty of research has been done on the subject, dating back to as far as the 1970s. Previous results showed that a love of chili is related to childhood experiences, and cultural influences affect our taste buds, too. But the latest study has found that a person's love of spicy food may be linked to his or her personality more than anything else, CBC News reported.

     “We have always assumed that liking drives intake---we eat what we like and we like what we eat. But no one has actually directly bothered to connect these personality traits with intake of chili peppers,” said Professor John Hayes from Pennsylvania State University, who led the study.       

But before you look at the study, you should first know that “spicy” is not a taste, unlike sour, sweet, bitter and salty. It is, in fact, a burning sensation that you feel on the surface of your tongue. This got scientists thinking that maybe a love of spicy food is brought about by people's longing for thrill, something they usually get from watching action movies or riding a roller coaster.

In the study, 97 participants, both male and female, were asked to fill out questionnaires about certain traits of their personality, for example. Whether they like new experiences or tend to avoid risks. They were then given cups of water with capsaicin(辣椒素), the plant chemical that makes chili burn, mixed into them.

By comparing the answers to questionnaires and what participants said they felt about the spicy water. Researchers found that those who most tended to enjoy action movies or take risks were about six times more likely to enjoy the spicy water.

    Interestingly, we used to believe that the reason some people can withstand spicy food is that their tongue have become less sensitive to it. However, this latest study has found otherwise. It's not that it doesn't burn as badly, it's that you actually learn to like the burn,” Hayes explained.