灌溉的缺点

　　题目回忆：灌溉的两个缺点，其中一个是过度灌溉会造成土壤过度湿润，产生大量菌类影响植物，另一个是盐分太多，有些地区下雨少，湖水盐分大，也会影响植物生长。

　　In the lecture, the professor talks about two disadvantages of irrigation. The first one is that plants won’t grow properly when there’s too much water. Take soil growing plants like melons as an example, when the soil gets too wet, fungus starts to form, and it will keep melons from growing properly. That’s why the whole irrigation system has to be designed carefully to avoid this problem. The second disadvantage is that in low-rainfall areas, salt builds up in lakes, when there’s too much salt in water, it will be harmful to plants as well.