Influence of phosphorus and organic carbon on benthic productivity and ecological diversity in coal mine lakes.

Mark Lund (MiWER), Naresh Radhakrishnan (MiWER),  Clint McCullough (MiWER), Lorraine Wyse, Digby Short (Premier Coal)

Can amendments of organic matter and nutrient improve ecological values of abundance and biodiversity in coal mine lakes?

The objective of this project is to examine whether pit lake ecosystem values rather than water quality could be considered by regulators as criteria for accepting pit lake closure and relinquishment back to the state. Specifically, the project seeks to:

  • determine which nutrient is limiting in each of the two lake acidity types and what, if any, thresholds exist for the amount of nutrient that needs to be added to increase algal growth.
  • test whether additions of simple nutrients (N and P) can encourage significant improvement of ecosystem values in pit lake types  with different acidity;
  • examine the role that bankside vegetation may play in providing inputs of nutrients and habitat for increasing aquatic biodiversity environmental values.

 

Photo: Riparian vegetation around pit lakes is often sparse; but may be very important to lake ecosystem function.


Photo: Benthic chambers are used to measure benthic primary productivity.

 

Photo: Water quality data are collected by submersible logging sondes.

 

Outputs

Lund, M. A.; Van Etten, E. J. B. & McCullough, C. D. (2013).Importance of catchment vegetation and design to long-term rehabilitation of acidic pit lakes. Proceedings of the International Mine Water Association (IMWA) Congress. Bunbury, Australia. Brown, A.; Figueroa, L. & Wolkersdorfer, C. (eds.), International Mine Water Association (IMWA), 1029-1034pp.