Modelling the effects of water-point closure and fencing removal: A GIS approach

Artificial water-points in the form of troughs or ground tanks are used to augment natural water supplies within rangelands in many parts of the world. Access to such water-points leads to the development of a distinct ecological sub-system, the piosphere, where trampling and grazing impact modify the vegetation.This study aims to consolidate existing information in a GIS based model to investigate grazing patterns within the landscape. The model focuses on the closure of water-points and removal of fences on Nanya Station, New South Wales, Australia.We found that the manipulation of water-points and fences in one management intervention may change grazing activity in a way different to that which would be experienced if each had been modified separately. Such effects are further modified by the spatial distribution of the water-points and the underlying vegetation.

► We developed a spatial model to investigate the distribution of grazing activity in a rangeland of New South Wales, Australia.
► The model permitted us to assess the change in the distribution of grazing activity in response to manipulation of water availability and access control through fencing.
► Our model showed that the time for which water is available, as well as the spatial distribution of water-points significantly affected the area accessed for grazing.
► The indiscriminate removal of fence-lines from grazing properties converted to conservation areas can have some detrimental results.
► Areas that previously required animals to walk longer distances from water would be closer to an accessible water-point as the fence was removed.