The Catchment Land Use For Environmental Sustainability Model?

1857 Words 8 Pages
The Catchment Land Use for Environmental Sustainability model (CLUES), designed by the National Institute of Water and Atmospheric Research Ltd (NIWA), provided the data for both the Nitrogen and the Phosphorus concentrations throughout New Zealand. The development of CLUES was through a consolidation of existing mapping procedures and modelling(EnviroLink, 2012), and contributed to by various research organisations (NIWA, 2016). From this collaboration, the models responsible for the Nitrogen and Phosphorus concentrations are: OVERSEER®; the Soil Plant Atmosphere System Model (SPASMO); and Spatial Regional Regression on Watershed Attributes (SPARROW). The CLUES model calculates annual mean nutrient concentrations, based on the statistical …show more content…
Unfortunately, with a 25.27% rate of positive correlation, this analysis is not an accurate means of testing the potential for New Zealand lakes to develop microcystins. Potentially, the cause of this inaccuracy could originate in several areas, or even a combination of areas, such as the use of temperature being derived from national terrestrial averages, rather than water temperatures; or the unsuitability of CLUES for nutrient analyses of lakes. The CLUES model represents lakes as ‘tagged’ river reaches. Thus, inflow nutrient loads cannot be calculated purely as the sum of the nitrogen and phosphorus river loads in the CLUES model. Inherently, this does not reflect the lake storage and attenuation terms (Semadeni-Davies et al., 2015). Additionally, errors could arise from the assumptions made by the CLUES model itself, for instance, temporal resolution. The CLUES model calculates water quality with an annual time-step and does not take seasonal differences in flow or farm practices into account. Moreover, the calculation methods and parameters, vary for different land use types, for instance, the OVERSEER® model calculates the nutrient loads from stock, whereas the SPASMO model is used to calculate nutrient loads from crops, and the SPARROW model is utilised for all other land uses (Semadeni-Davies et al.,

Related Documents