Biodiversity is closely linked with the idea of Interdependence: that every living thing directly or indirectly influences the welfare of everything else and that all living things are in balance in a stable environment
Below are lists of things you might do to improve the balance in the environment.
How do you think they will work?
Things that help
Joining a volunteer environmental group allows you to set aside some time to do a job for the benefit of others.
You can learn from others, and share your ideas and concerns with them. It may result in you discovering new interests and developing new skills.
This can include any activity or project that makes more efficient use of natural resources, or reduces the demands you make on them. e.g. a garden with a low water requirement can save water or a compost heap (or worm farm as shown above) that can recycle some of your food waste.
This will make less demand on landfill sites and reduce the transportation cost for waste disposal, as well as giving you a great soil conditioner.
Shelter for native fauna can be many things: it may be planting dense shrubbery where small birds can hide from predators, or… even nest boxes in an area lacking old trees for microbats and birds not able find hollow logs.
You can get help from Habitat for Wildlife.
The best way to provide food for native birds and animals is by growing a variety of native plants: small flowers are just as important as large ones.
Birds may feed on the plant seeds or on insects and other small animals in the plants. Not using insecticide is also important, as dead, or immune insects will pass the poison on to anything that eats them.
Of course this will involve collection and some sort of storage. There are devices on the market that make it easy to collect some of the rainwater from a downpipe from your household gutters.
You will need some space to place a storage tank, but again there is quite a variety available from large conventional tanks to small makeshift ones.