如果土壤中盐分太濃,是会影响作物生长的。土壤中盐分过多,往往可用肉眼看出来。但是有时修肉眼却不容易看出。为了解决这个問題,国外有科学家用对紅外綫特別敏感的胶片来进行航空摄影,以檢查大面积土地上的盐分。如果棉花生长正常的話,那么大部分紅外线都会从棉花叶面上反射掉;因此,棉叶在紅外线照片上呈白色。但是,如 If the soil is too salty, it will affect the growth of the crop. Too much salt in the soil can often be seen with the naked eye. But sometimes it is not easy to see the naked eye. In order to solve this problem, foreign scientists use aerial films that are particularly sensitive to infrared rays for aerial photography to check the salinity of large areas of land. If the cotton grows normally, most of the infrared rays will be reflected off the cotton leaf surface; therefore, the cotton leaves appear white on the infrared photo. However, if