Increasing levels of recreational use of national parks can lead to deterioration in the natural conditions of an area and the experiences that visitors have. Carrying capacity(see Tourism in National Parks and Protected Areas). In reality, the use levels an area can sustain will depend on a multitude of environmental, social and management factors and these factors will vary over time. The carrying capacity concept assumes the intrinsic character of the land base will determine how many people are too many. This approach has not been successful in solving the problem through setting visitor limits and has led to other approaches based on achieving a set of desired social and environmental conditions for a park/location rather than one based on the question: “how many visitors is too many?”. Models based on desired outcomes like Limits of Acceptable Change (LAC), VERP and VAMP (See 'Tourism Planning Framework') have more popular application with park managers than chasing elusive carrying capacity numbers.
This report examines and reviews visitor impact modelling applications in Australia. A variety of visitor impact models and processes have been used in Australia and internationally but the extent of their use and perceived effectiveness are not well ...
... The alternative approach of first selecting indicators and setting out to ... to a clearer understanding of the significance, desirability, or limits of acceptable ...
http://researcharchive.lincoln.ac.nz/dspace/bitstream/10182/450/3/TREC_Report_42.pdf
... and maximum permissible MVAR loading limits for generators, line loading limits etc ... Based on its results, the optimal reactive power control setting for current ...
http://researcharchive.lincoln.ac.nz/dspace/bitstream/10182/4176/1/VoltageVar_control.pdf
... for the further study and proposal of a mechanism for the setting of regulations ... In most cases lower limits are deduced by extrapolating from experimental data ...
http://researcharchive.lincoln.ac.nz/dspace/bitstream/10182/1376/1/crm_ip_10.pdf