Publication Details

North, H. & Russell, K. G. (2005). Factors associated with trends in bare ground in high country. In G. Wake (Eds.), 2005 Mathematics-In-Industry Study Group (pp. 103-117). New Zealand: Mathematics-In-Industry Study Group, Centre for Mathematics in Industry, Massey University.


Soil erosion in the Canterbury high country has been a concern for many years, and Environment Canterbury wishes to encourage land management practices that will preserve soil quality and vegetative cover. Environment Canterbury brought to MISG2005 a data set spanning three decades of bare ground monitoring in the Canterbury high country, along with data on factors with potential to impact on the processes of revegetation. These include topographic and climate data, soil nutrient status and land management factors. The study group analysed these data with the aim of determining whether trends in bare ground can be predicted from the potential causative factors. Analysis was difficult due to the high level of confounding between many of the variables, such as soil quality with land management. However a predictive model of change in percent bare ground was derived (explaining 63% of the variation in the data) in which the most important factors were fertiliser application, percent bare ground at the start of the monitoring period, annual average temperature and winter rainfall. Removal of low intensity grazing (to no grazing) had no discernable effect on percent bare ground.

Link to publisher version (URL)

Mathematics-in-Industry Study Group