Land and water use and management

2016

Risks from changes to land management arise mainly through potential hydrological and water quality changes, whereas those from water management relate to changes in the timing and nature of flows that may be beneficial or detrimental to aquatic ecosystem health.

As a whole, land-cover or land-use changes are not being made on the same scale as in past decades and centuries. However, some changes may occur anyway because of other factors, such as climate influences on rangeland fire regimes. In expanding extensive land management practices into much of the less-developed areas of northern Australia, we raise the risk of implementing management regimes that are not compatible with either the natural (and increasing) variability of the environment, or the needs of tropical surface-water and groundwater ecosystems—many of which are not well studied or understood. Risks in developing Australia’s north include surface-water regime change, surface-water pollution, groundwater extraction, seawater intrusion, and accelerated spread of pest plants and animals.

However, and conversely, we have a significant body of practice and knowledge to help avoid the land and water management mistakes of the past. These range from practical on-ground management techniques to limit the expansion of pest species (e.g. Florance et al. 2011, Tingley et al. 2013) to policy and process changes that can reduce the risks involved in management of threatened species (McDonald et al. 2015). Projections of the future distribution of pest plants and animals, such as those driven by changes in climate, development and infrastructure, reinforce the requirement for ongoing good monitoring and management of pest species. Operational monitoring and management programs, such as Queensland’s Indigenous Land and Sea Ranger program, provide approaches that can target pest and weed control.

In the short term, coal-seam gas and large coalmining developments pose a range of risks to inland waters. These risks, which will be considered as part of regulatory processes, are intended to be investigated by the Bioregional Assessment Programme, within which individual bioregional assessments will:

  • define, characterise and explain conceptual models that establish causal pathways describing the chain of interactions and events connecting depressurisation and dewatering of coal seams at depth with impacts on anthropogenic and ecological receptors located at depth or the surface
  • generate quantitative, semi-quantitative or qualitative analyses of the likelihood of impacts of coal seam gas (CSG) and coal mining developments on receptors from the application of ecology, surface water and groundwater hydrology, hydrogeology and CSG or coal resource development models
  • develop improved assessments of the likelihood of risks to receptors and the subsequent values of water-dependent assets from CSG and coal mining developments
  • provide information on the level of confidence of scientific advice on these impacts
  • identify monitoring programs, bioregional assessment review frequency and additional risk assessment studies that could be undertaken outside of the bioregional assessment process to help minimise impacts of CSG and coal mining developments on water resources. (Barrett et al. 2013)

Assessment reports will be progressively available through 2015–17, initially comprising context statements, resource assessments, and receptor and asset registers. Impact reports and risk analyses will be released later.

Disaggregation of responsibility for driving, and resource reductions for implementing, the National Water Initiative raise risks for future water management, especially in light of policy that affects water resources, such as the development of Australia’s north (NWC 2014). These risks include:

  • noncompletion of National Water Initiative elements, such as water reform, and lack of national leadership in water
  • reduction in independent oversight and public reporting, such as that seen with national water market reporting
  • failure of implementation of water quality objectives in water management
  • failure of full implementation and auditing of the Murray–Darling Basin Plan.

Current and emerging risks to inland water environments assessment summary shows the risks to inland water environments. In addition to those listed, there are many less significant risks, particularly at the local or point scale.

Current and emerging risks to inland water environments

  Catastrophic Major Moderate Minor Insignificant
Almost certain

 

  • Warming climate leading to changed flow regime or groundwater condition
  • Increased water extractions leading to changed flow regime or groundwater levels
  • Agricultural run-off leading to nutrient pollution and sedimentation of rivers
  • Flow regime alteration arising from water infrastructure development
  • Minor chemical pollution event
Not considered
Likely
 
  • Invasive aquatic pest animal damage
  • Major river or aquifer salinisation because of historical land clearance
  • Aquatic weed invasion leading to habitat loss
  • Extreme weather events leading to sedimentation of rivers or coastal aquatic habitats
  • Urbanisation leading to loss of wetland habitat
  • Changes in fire frequency or intensity
  • Salinisation or contamination of groundwater or rivers because of gas mining or coalmining
  • Warming climate increasing aquatic habitat temperatures
  • Blue-green algal outbreaks
  • Livestock damage to riparian areas
Not considered
Possible
   
  • Major chemical pollution event
  • Extensive disease outbreak for multiple aquatic species
  Not considered
Unlikely
        Not considered
Rare
Not considered Not considered Not considered Not considered Not considered
           

 

Argent RM (2016). Inland water: Land and water use and management. In: Australia state of the environment 2016, Australian Government Department of the Environment and Energy, Canberra, https://soe.environment.gov.au/theme/inland-water/topic/2016/land-and-water-use-and-management, DOI 10.4226/94/58b656cfc28d1