Not sure about regional biodiversity but probably local biodiversity will be affected in some way. Open-cast mining in particular can be very destructive. Depending on how widespread the building activities are and whether or not they involve leaving any greenbelts through the developed area, biodiversity can be adversely affected. Development in general is detrimental to sensitive ecosystems, especially where pests (invasive species) are prone to occur by using greenbelts as corridors to quickly establish themselves and increase their populations, decreasing biodiversity overall.
Thanks Victor. Very true. How can scientists influence policy makers who may not be aware of these pitfalls. What about the mining giants themselves, do they care about biodiversity?
The first step is to take that concern to your local MP. If that fails (as it often does), join an environmental lobby group or set one up if there's enough support. Scientists don't like to become activists, but sometimes we have to wear more than one hat! See how Forest & Bird in New Zealand tackled mining in sensitive areas head-on: http://victormeyer.net/F&B/Habitat_Aug-Dec_10.pdf or use this search tag: http://www.forestandbird.org.nz/search/node/mining.
Of course, the mining industry cares primarily about making money. Biodiversity only gets considered for the sake of ISO compliance.