Composting

By Gary Garriott
Broadcast: July 22, 2003
This is Robert Covent with the VOA Special English Agriculture Report.
Many farmers around the world are 1)composting to improve their soil so they can produce better crops. Composting is the mixing of plant or animal wastes so they break down and produce simpler substances.
Farmers add compost to their soils instead of burning the plant and animal wastes or throwing them away. Compost is an example of a natural organic fertilizer. Organic fertilizers help to make soils rich so that they produce more crops for a longer time.
During the growing season, plants take gases from the air such as carbon, 2)hydrogen and oxygen. They combine these gases with minerals from the soil.
After the growing season ends, many parts of the plant die. Farmers gather a large amount of dead plant materials into small hills called compost piles. They may add animal wastes. They must add water so the materials will break down or 3)decay 1.
Soon the plants are attacked by insects and organisms including worms and 4)bacteria. Oxygen helps the organisms change the plant materials more rapidly. The plants decay into a mixture that can be spread on the farmland where the crops are growing. The compost returns needed 5)nutrients to the soil.
Some rules need to be followed to produce the best quality compost. Good compost piles need water to speed the process of decay. Yet the piles should not be too wet or the plant material will be ruined. The temperature of the compost pile should not be too high or too low. The best temperature for a compost pile is about thirty to thirty-seven degrees 6)Celsius 3. You can turn the pile over and over to help cool down the material, and add more oxygen to the mixture which helps it decay.
Sometimes small animals such as rats and mice like to eat the composting materials. This can be prevented if you add a thin amount of soil to the top of the compost pile.
Farmers who use compost can increase the amount and quality of their crops. Computer users can find more information about composting from Volunteers in Technical Assistance or VITA.
VITA helps people around the world use science and technology to solve problems. Their Internet address is www.vita.org.
This VOA Special English Agriculture Report was written by Gary Garriott. This is Robert Covent.

注释：
1) compost [5kRmpRst] vt.施肥；给…施堆肥
2) hydrogen [5haidrEudVEn] n.氢
3) decay [di5kei] vi.衰减, 衰退
4) bacteria [bAk5tiEriE] n.细菌
5) nutrient 2 [5nju:triEnt] n.营养物
6) Celsius [5selsjEs] adj.摄氏的