Human Impacts on the Environment Crossword

A substance that contaminates air, water or land.
These decompose extremely slowly, allowing them to accumulate to toxic levels as they are passed along food chains.
These are usually only damaging when added to the environment more quickly than they can decompose.
Are organisms whose presence or absence provides information on the environmental conditions in a specific area.
These include carbon dioxide, sulfur dioxide, and nitrogen oxides.
These are tiny particles suspended in air, which are usually produced by the combustion of fossil fuels.
Caused by a build-up of greenhouse gases, which leads to an increase in the Earth's temperature.
An atmospheric gas that absorbs infrared light.
Tiny marine animals that extract carbon from the carbon dioxide to make their skeletons and shells.
A protective part of the atmosphere that absorbs some of the Sun's damaging ultraviolet rays.
A mixture of air pollutants and particulates that is sometimes found in the lower levels of the atmosphere.
The accumulation of nutrients in water, which causes excessive algal growth.
Plastic, metal, paper and other man-made substances.
Herbicides and pesticides, crude oil and waste from industrial processes.
A natural biological processes to decompose organic materials.
The number of different species within a specific habitat.