1 . Bees are responsible for one in every three bites of food: from almonds (杏仁) to berries and the alfalfa (苜蓿) that feeds dairy cows. Our diets and agricultural economy hinge on a healthy bee population.
However, rapid declines in bee population around the world put additional stress on an already unstable food supply by depressing yields and agricultural efficiency. While bee biologists do not foresee upcoming food system collapse without honey bees, we do know that agriculture would quickly become unrecognizable—and much more limited.
Farmers are on the frontlines of the economic impacts of bee decline. For example, the cost of almond pollination (授粉) has nearly tripled since colonies began collapsing in 2004, costing that industry over $83 million per year.
The causes behind recent bee declines are not a “mystery”. Independent scientists now largely agree that bee declines are caused by a combination of several factors, including: poor nutrition, habitat loss and pesticide (杀虫剂) exposure.
In the last several years, pesticides — both alone and in combination with other pesticides — have emerged as a key catalyst (催化剂) behind this disturbing phenomenon, both because of their direct toxicity to bees and their indirect and cascading effects.
Scientists know that individual bees can be acutely poisoned while flying through pesticide-contaminated planter dust in a recently planted corn field. More commonly, they are chronically poisoned at sublethal (亚致死) levels by eating and drinking contaminated pollen, nectar and water over time. Bees are then more likely to get sick.
As an indicator species, honey bees are sounding an alarm that we ignore at our peril. Among their lessons: industrial agriculture has gone off the rails. The pesticide treadmill has kicked into high gear with a class of dangerous systemic pesticides—while regulators were asleep at the switch. So let’s keep the heat on decision makers to take meaningful action.
1. What does the underlined phrase in paragraph 1 mean?| A．Cut down. | B．Contribute to. | C．Depend on. | D．Go against. |
| A．The impact of rapid declines in bee population. | B．The role of farmers in agriculture. |
| C．The ignorance of the effect on food system. | D．The cost of almond pollination. |
| A．Poor in nutrition. | B．Economic impacts. |
| C．Loss of habitat. | D．Exposure to pesticides. |
| A．To express sympathy for the affected farmers. | B．To show the factors resulting in the bees’ crisis. |
| C．To explain a key catalyst to the bees’ problem. | D．To urge decision makers to take action for bees. |
2 . Lightning can strike anyplace on Earth. In fact, there are about 6,000 lightning strikes every minute, which is more than 8 million strikes every day. The risk of being struck by lightning is low, but the consequences of lightning strike injuries are serious. Even though your home is a safe shelter during a lightning storm, you might still be at risk. About one-third of lightning-strike injuries occur indoors.
Avoid water.
Do NOT bathe, shower, wash dishes, or have any other contact with water during a thunderstorm.
Do NOT use anything connected to an electrical outlet (电源插座), such as computers, game systems, washers, or stoves. Lightning can travel through electrical systems, radio and television reception systems, and any metal wires or bars in concrete walls or flooring.
Avoid windows, doors, porches, and concrete.
Don’t use corded (有线的) phones.
Corded phones are NOT safe to use during a thunderstorm. Do NOT use them.
Follow the safety measures above can minimize your risk of being injured indoors on lighting days. Don’t take it for granted that only outdoor activities can put you in a dangerous place. Keep it in mind that inappropriate indoor activities can also be disastrous.
| A．Here are some tips to keep safe and reduce your risk of being struck while indoors. |
| B．In addition, follow up on the latest information about the storm. |
| C．However, it is safe to use cordless or mobile phones during a storm. |
| D．Stay away from windows and doors, and stay off porches. |
| E．Some outdoors measures can keep you safe and prevent you from being attacked. |
| F．Lightning can travel through a building’s water pipe system. |
| G．Don’t touch electronic equipment. |
3 . “A beautiful field of flowers can be a rather noisy place. It’s just that we can’t hear the sounds.” Scientists at Tel Aviv University have conducted a six-year experiment, proving that plants make noise in certain stressful situations.
Plants produce a high frequency (频率) clicking sound, and when short of water, or damaged, the clicks become far more regular. They also made different sounds, depending on whether they were thirsty or injured. “Each plant and each type of stress is related to a specific sound,” said Professor Lilach Hadany, who led the research study.
Focusing particularly on tomatoes, wheat and corn, the plants were placed in a soundproof(隔音的)room and recorded by microphones. Some plants were starved of water, others cut, and a control group was left undamaged. The researchers used an algorithm (算法) to separate the noises, suecessfully telling the difference between the sounds depending on whether they were dry or cut. The algorithm did this in a greenhouse setting which included far more surrounding sounds, but it was still able to recognize the particular cries for help of the plants.
On average, the human ear can hear sounds up to around 20kHz, while the sounds produced by plants are in the 40-80kHz region, far beyond our hearing. “The sounds made by plants can’t be heard by humans but can probably be heard by various animals, such as bats, mice and insects,” Hadany tells us. Though this has yet to be proven, it’s possible that these creatures use this information to choose which plants to eat.
A study led by Reda Hassanien of China Agriculural University in Beijing years ago, also proved that plants reacted to sound waves, with some plants greatly increasing their yield. While evidence shows that plants can react to sounds, there’s no evidence today that they can actually hear them.
1. What can we know from the six-year experiment?| A．Plants of different types make the sound of the same frequeney. |
| B．Plants produce more regular sound in certain stressful situations. |
| C．Plants make sounds with a much lower frequency when stressed. |
| D．Plants make the sound of the same frequeney whatever the situation. |
| A．To record the sounds. | B．To control the sounds. |
| C．To produce the sounds. | D．To identify the sounds. |
| A．Plants can hear each other’s cry for help. |
| B．Animals can hear the sounds made by plants. |
| C．Plants can make sounds and respond to sound waves. |
| D．Animals decide what to eat based on the sounds plants make. |
| A．Sounds That We Can’t Hear |
| B．Beautiful Songs from Plants |
| C．Plants React to Different Types of Stress |
| D．Plants Talk, Especially When Stressed |
