VOA慢速英语2009-Agriculture Report - Home Gardening: What to

This is the VOA Special English Agriculture Report.

Soil naturally contains harmless¹ amounts of lead, along with other metals. Because of pollution, however, the amounts are higher the closer you get to cities and towns. But experts say this should not stop gardeners from growing food if they take safety measures.
　
Lead from paint, fuel and industry can pollute soil and harm children

David Johnson is a chemistry professor in the State University of New York's College of Environmental Science and Forestry². He explains that lead can enter the ground from leaded paint and leaded fuel and from industry.

And once lead gets into the soil, it stays a long time. It remains³ an environmental threat especially to children. Lead can harm mental and physical development even in babies before they are born.

If a test finds that soil has too much lead, you might be advised to remove the soil or cover it with sod grass. Different countries have different levels that they consider acceptable⁴.

Carl Rosen of the University of Minnesota Extension⁵ notes that concerns about lead have increased now that more people are planting gardens. But Professor Rosen says plants generally do not absorb much lead. He says there is likely more risk from lead dust on plants or from playing in the soil than from the plant itself.

Still, some plants do absorb more than others. Experts say good choices for the garden include tomatoes, peppers, beans and okra. Among the plants that can absorb more contaminants, they say, are root crops, leafy vegetables and herbs. If you grow carrots, for example, you might want to peel them. Dirt may be harder to remove from some crops than from others. But all produce should be washed.

Gardens should be planted away from roads and structures, especially old buildings. Home gardeners should plant away from the foundation⁶ of their house. And lead amounts can be especially high near industrial areas and waste dumps⁷.

Soil should also be tested for its pH level, a measure of the acid⁸ and alkaline balance. Experts say the ability to take up lead is reduced when the pH level is above six and a half. Adding organic⁹ material such as compost to soil can also make lead less available to plants.

Some people attempt a process called phytoremediation. They try to remove lead from soil by growing certain plants that collect it. But Professor Rosen says the process is complex and may not work.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. For more gardening information, go to voaspecialenglish.com. I'm Steve Ember.

1 harmless   

adj.无害的，无恶意的

参考例句：

• This experiment was harmless to the animals.这个试验不会对动物造成伤害。
• He was a harmless sort.他是一个不怀恶意的人。

2 forestry   

n.森林学；林业

参考例句：

• At present, the Chinese forestry is being at a significant transforming period. 当前, 我国的林业正处于一个重大的转折时期。
• Anhua is one of the key forestry counties in Hunan province. 安化县是湖南省重点林区县之一。

3 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

4 acceptable   

adj.可接受的，合意的，受欢迎的

参考例句：

• The terms of the contract are acceptable to us.我们认为这个合同的条件可以接受。
• Air pollution in the city had reached four times the acceptable levels.这座城市的空气污染程度曾高达可接受标准的四倍。

5 extension   

n.伸长，扩大，伸展；延长，延期；延长部分，扩大部分；电话分机

参考例句：

• The pupils disliked the extension of the term.小学生们不愿延长学期。
• Our extension is nearly finished.我们的扩建部分已接近完工。

6 foundation   

n.[pl.]地基；基础；基金会；建立，创办

参考例句：

• The foundation of the university took place 600 years ago.这所大学是600年前创办的。
• The Foundation gives money to help artists.那家基金会捐款帮助艺术家。

7 dumps   

n.抑郁v.倾倒( dump的第三人称单数 )；丢下；随便堆放；释放

参考例句：

• They eke out a precarious existence foraging in rubbish dumps. 他们靠在垃圾场捡垃圾维持着朝不保夕的生活。 来自《简明英汉词典》
• It's no use letting yourself fall into the dumps. 你听任自己的情绪低沉下去一点用也没有。 来自《简明英汉词典》

8 acid   

n.酸；酸性物质；adj.酸的，酸性的

参考例句：

• Handle with care,or the acid may get out.小心轻放，否则酸会溢出来。
• The acid has been eating away the sides of the container.酸腐蚀着容器的四壁。

9 organic   

adj.有机的，有机物的；有组织的

参考例句：

• Organic farming is expanding everywhere.有机农业正在各地迅速发展起来。
• The organic fertilizer shall keep the soil in good heart.这有机肥一定会使土壤保持肥沃。