土壤科学原理与实践土壤有机质

1、 侯彦林侯彦林 中国中国科学院研究生院科学院研究生院 20201010年秋季学期年秋季学期 单词：单词： 1. insect n.昆虫昆虫, 卑鄙的人卑鄙的人 adj.虫的虫的, 虫子一样的虫子一样的, 对付虫子的对付虫子的 2. improved adj.改良的改良的 3. supervise v.监督监督, 管理管理, 指导指导 4. potato n.马铃薯马铃薯 5. barley n.大麦大麦 6. clover n.植植三叶草三叶草, 苜蓿苜蓿 7. fertilizer n.肥料肥料(尤指化学肥料尤指化学肥料), 动动受精媒介物受精媒介物 AGRICULTURE REPORT J

2、une 25, 2002: Organic Farming Study By George Grow This is the VOA Special English Agriculture Report. Agricultural scientists in Switzerland(瑞士瑞士) have demonstrated（示范）（示范） the long-term effects of organic farming methods. Organic farms use no man-made chemicals to increase crops or control insects

3、1 and disease. The study showed that organic fields produced fewer crops, on average, than other fields. However, the scientists say the organic methods improved2 the health of the soil and used half as much energy. Scientists at the Research Institute of Organic Agriculture in Frick, Switzerland, s

4、upervised3 （指导、管理）（指导、管理） the study. They reported their findings（发（发 现）现） in Science magazine, the publication of the American Association for the Advancement of Science. It（有机农业研究）（有机农业研究） was one of the longest-running（运行）（运行） studies of its kind. The Swiss scientists compared the effects of orga

5、nic and traditional farming methods over a period of more than twenty years. They grew crops on four fields of land in Switzerland. Two fields were grown using traditional farming methods. The others were grown using organic farming methods. The scientists grew potatoes4, barley5, winter wheat, beet

6、s and grass clover6. The crops, planting methods, and soil use （名词）（名词）were similar in all the fields studied. The study found that the organic fields produced about twenty percent fewer（少（少20%） crops than the other fields. However, the farmers used less fertilizer7 and energy on the organic fields.

7、 They found the organic fields were healthier. The scientists say the organic fields had more nutrients in the soil. The soils in the organic fields also had more biological activity than the other fields. The organic fields had more helpful organisms and a larger number of different organisms. The

8、organic fields had almost two times as many insects, including helpful insects. In traditional farming, chemicals designed（用于消灭）（用于消灭）to kill harmful insects also can kill helpful ones. The researchers say the findings s h o w t h a t o r g a n i c c r o p production rates change little over time, a

9、nd that soil fertility increases. They say the findings suggest（暗示着）（暗示着） that organic f a r m e r s c a n h e l p t h e environment by increasing soil fertility. Organic farming is becoming increasingly popular in some countries. Many people believe that eating organic food is more healthful than eating food grown with chemicals. Some people are willing to pay more money to buy organic food. This VOA Special English Agriculture Report was written by George Grow. 2002/3/30 2002/3/30 下午下午春雨过后春雨过后 （节选）（节选） 人是要跟随感觉走，还是要朝着目标人是