there is no oxygen left and aquatic life begins to die. Figure 2 غير المعالجة و تصرف كافي التي Farmers add fertilizers to the soil to help their crops grow. Sometimes the fertilizers are washed out of the soil into rivers. The fertilizer helps water plants to grow and the river soon becomes full of plants. When the plants die they are eaten by bacteria. The bacteria reproduce very quickly and once again the oxygen in the water gets used up. . . Figure 3 Farmers also add herbicides and pesticides to their crops. Sometimes these chemicals drain into the rivers too. . Many factories dump poisonous chemicals into the water. There was a fishing town in Japan where a plastics factory was dumping waste mercury into the sea. . Figure 4 Oil is carried around the world in huge tankers. Sometimes tankers run into rocks along the coastline and crude oil pours into the sea and onto the beaches or they have an accident
there is no oxygen left and aquatic life begins to die. Figure 2 غير المعالجة و تصرف كافي التي Farmers add fertilizers to the soil to help their crops grow. Sometimes the fertilizers are washed out of the soil into rivers. The fertilizer helps water plants to grow and the river soon becomes full of plants. When the plants die they are eaten by bacteria. The bacteria reproduce very quickly and once again the oxygen in the water gets used up. . . Figure 3 Farmers also add herbicides and pesticides to their crops. Sometimes these chemicals drain into the rivers too. . Many factories dump poisonous chemicals into the water. There was a fishing town in Japan where a plastics factory was dumping waste mercury into the sea. . Figure 4 Oil is carried around the world in huge tankers. Sometimes tankers run into rocks along the coastline and crude oil pours into the sea and onto the beaches or they have an accident