Human Intervention at Tumbi Wetlands Bushcare 
How can these chemicals be a problem?
Overuse of weedkillers, pesticides and fertilizers can lead to damage to other organisms apart from the targets.

Pesticide use can kill off predator insects
that would keep the pests under control in a balanced environment
or destroy insects important for fertilisation of some plants.
Be careful with garden chemicals
Excess fertilizers can be leached out of the soil and washed away so that it encourages the growth of exotic weeds rather than native plants near our waterways.