First of all we need to about "Environment". The word environment is comes from the French word, 'Environ' which means 'Surrounding'. Our surrounding includes biotic factor(human, plant, animals, microbes) and abiotic factor(light, air, water, soil).

Then we need to know about "Resource". A resource is something that can be used for making profits or benefits, whether that be a source, supply, or support.

So, Environmental Resource is earth is considered a home for many life forms, and to sustain life on Earth, we need some resources that we derive from nature. These resources are called natural resources(coal, oil, timber, etc). Management system of this natural resources is basically environmental resource management.