Phosphorus Cycle and Biochemical of Lake Neerabup A wetland can function as a sink or transform nutrients, organic and inorganic materials. Wetlands constitute a natural factory for filtration and purification of sediments and organic matter (Group, 2014). Phosphorus can enter wetlands as suspended solids or dissolved phosphorus. A significant concentration of phosphorus is associated with wetland sediments (Walbridge and Struthers, 1993). Phosphorus in the wetland is removed by plants and microbial organisms (Group, 2014). Total phosphorus (TP) is an inorganic form, mainly derived from artificial sources, on the other hand the organic form; phosphate (PO4-P) is derived from plants and animals and their remains (Group, 2014). In wetland soils, microorganisms, plants and geochemical processes are powerless factors to deal with dissolved phosphorus. (Walbridge and Struthers 1993). Algae uses excess phosphorus and nitrogen to grow and multiply rapidly to large numbers, thriving when the weather is warm and sunny and the water flow is slow. Higher levels of phosphorus and nitrogen present in the systems and wetlands of the Swan and Canning Rivers have caused excessive growth of blue-green algae and other algae, while low levels of phosphorus can sustain life (SERCUL, 2014). As a result, nutrients accumulate in the environment. of human activity. We use too many nutrients in our daily lives. Nutrients entering the Swan, Canning and wetlands mainly come from fertilizers, intensive agricultural resource use, garden fertilizers and industrial or urban leakage. (SERCUL, 2010). It should be noted that total phosphorus is highly variable depending on rainfall events and the above results should be treated with caution (Group, 2014). Phospho...... middle of paper ......nd and Lake Neerabup); the trigger value for phosphorus should be considered the same and regulated as shown in the table. Selected Parameters Guidelines Applications and Limitations Nutrient Contaminants in Surface Water Total Phosphorus Concentrations ANZECC Guidelines for South West Australia for Lowland Rivers (ANZECC and ARMCANZ 2000) SCCP Objectives for the total nitrogen and total phosphorus concentrations (SRT 2004). SCCP targets relate to the number of total nitrogen and total phosphorus samples that exceed the target value relative to the maximum number of exceedances allowed. The target values ​​apply only to the winter period and all three years of data are used to assess compliance according to Swan River Trust 2004. These targets may be applied in this study at the request of the SRT for guidance only. Table 2 Source: Nice et al., 2009