Pollution- IGCSE human influence on ecosystems

In this video from simple biology, Mr. Mahdi explainshow human population is booming which increases the need of agriculture and production of food, how human activities like burning fossil fuels in vehicles and factories, dumping sewage in rivers and lakes, industrial smoke and gases emitted into the atmosphere, and more garbage will be produced. Accidents in factories and natural events like forest fires and volcanic eruptions, all cause pollution.
after defining pollution and identifying the types of pollution which are: air pollution, water pollution, soil pollution, land pollution, light pollution, noise pollution. water pollution is caused from excess use of fertilizers, herbicides and insecticides; dumping raw sewage in rivers and lakes; acid rain; industrial wastes and chemicals leaching into water. eutrophication develops when fertilisers and raw sewage into water which results in growth of algae on the surface of water which blocks sunlight from reaching water plants so less photosynthesis and less oxygen is released into the water, bacteria multiply and decompose algae which increases aerobic respiration and reduce oxygen in water. Air pollution caused by emissions of gases like sulfur dioxide , carbon dioxide, carbon monoxide and nitrogen oxides which will cause acid rain, respiratory and heart problems, global warming and depletion of ozone layer. soil pollution is also discussed in details including garbage and non-biodegradable plastics which harm the ecosystems by harming animals and destroy habitats because it stays in the environment for long time. At the end, solution are suggested to reduce pollution.
for habitat destruction video:

for food supply video: