Australian Natural Resources Atlas

Natural Resource Topics

Landscape - carbon, nutrients, water and productivity - Broughton River

Broughton River

Location Map

Why are material budgets useful?

The availability of light, water and nutrients determines the capacity of land to produce natural vegetation and agricultural yield. In Australia, long-term availability of resources and the consequent potential for generating yield, can be assessed by examining the mass balances of the key resources: water and nutrients (in this case nitrogen and phosphorus). Mass balance gives a quantitative picture of:

The mass balances of water and nutrients are linked by carbon (or biomass) since plant biomass is approximately 50% carbon. Balances and cycles of water, nitrogen, phosphorus and carbon interact and constrain each other.

The figure below provides a schematic of how the couple balances carbon, nutrients and water were constructed and linked to sediment and nutrient transport.

Major pools and fluxes in the linked water, carbon, nitrogen and phosphorus cycles through the atmosphere, plants and soil. Net primary productivity is the sum of photosynthesis and plant (not litter and soil) respiration.

Landscape carbon, nutrients, water and productivity budgets

The table below presents the key material budget terms modelled or collated as part of the Australian Agriculture Assessment 2001 projects.

The budget terms cover:

Detailed separately are:

Key river basin characteristics such as broad agricultural land use categories and climate are provided for context. All attributes are presented as aggregate mass, rate, ratio or percentage estimate at a river basin scale

Context for understanding the material budgets for Broughton River

Attribute Unit Basin value Median Australia-wide value
Basin area km2 16,371 7,208
Improved pasture % 8 1
Cropping % 45 0
Horticulture % 6 1
Total agricultural land proportion % 60 7
Climate
Rain mm/y 416 860
Total evaporation mm/y 333 584
Runoff mm/y 83 249

Carbon, nutrients, water and productivity in Broughton River

Attribute Unit Basin value Median Australia-wide value
Net Primary Production tC/ha/y 3 3
Plant carbon t/ha 73 76
Litter + soil carbon t/ha 102 78
Landscape nutrients
Nitrogen from fertiliser kgN/ha/y 6 0
Nitrogen fixation kgN/ha/y 54 17
Total nitrogen kgN/ha 8,520 6,742
Mineral nitrogen kgN/ha 88 85
Mineral nitrogen concentration in soil water mgN/kgwater 127 50
Nitrogen leached kgN/ha/y 17 9
Nitrogen volatilised kgN/ha/y 2 2
Phosphorus from fertiliser kgP/ha/y 5 0
Total phosphorus kgP/ha 1,111 1,062
Dissolved mineral phosphorus kgP/ha 14 14
Phosphorus concentration mgP/kgwater 20 9
Phosphorus leached kgP/m2/y 3 1

Further information

Before you download

Most publications are downloadable as PDF files. Adobe Acrobat Reader  is required to view PDF files.

If you are unable to access a publication, please contact us to organise a suitable alternative format.

Key

   Links to an another web site
   Opens a pop-up window