BIOLOGY UNIT 3B GCSE

There are over SIX BILLION PEOPLE in the worlddue to medicine and farming methods which have REDUCED the number of people dying from disease and hunger.  increasing population puts pressure on environment  higher standard of living also use more energy for manufacturing processes raw materials are being used up quicker than they're being replace WE also producing more wastewater : sewage and toxic chemicals from industry can pollute, rivers and oceans affecting the plants and animals that rely on them for survivalland , we use toxic chemicals for farming. we also bury nuclear waste and dump lot of household waste in landfill sitesAir : smoke and gases released into the atmosphere can pollute the air e.g sulfur dioxide can cause acid rainMore people means Less land for plants and other animalsfour main human activities we do : building farming dumping waste quarrying for metal ores

Carbon dioxide is removed from the air and stored in various places  carbon is present in atmosphere as CO2 may processes lead to CO2 being released e.g fossil fuels too much CO2 cause global warming CO2 can be LOCKED UP in NATURAL STORES :  Oceans, lakes and ponds green plants  peat bogs

Deforestation means chopping down treesdone for reasons such as :  to provide timbre for building materials  clear more land for farming  (more food)  to produce paper from wood Leads to FOUR MAIN reasons :  more methane in the atmosphere more carbon dioxide in the atmosphere  less carbon dioxide taken in  less biodiversity (variety of different species Destroying peat bogs adds MORE CO2 to the atmosphere

human impact

greenhouse effect

peat bogs