Australian Rangeland Society

The WA Department of Primary Industries and Regional Development recently made pastoral lease scale satellite information available to all pastoralists to help them with their decision making.

The satellite data comes in the form of normalised differential vegetation index (NDVI) graphs.  NDVI is an index which can be used to estimate the amount of green vegetation: it measures the difference between near-infrared (which green vegetation strongly reflects) and red light (which green vegetation absorbs). As such, NDVI can be used to help estimate the amount and health of green vegetation, and the response of pastures to rainfall.

The NDVI information is presented as graphs which show the averaged NDVI values for an entire lease (see example below). Each graph then allows users to compare current seasonal conditions with the past two years, along with historic good, average and poor years.  This can then help to put the current season into perspective in terms of vegetation growth.

Figure 1 An example lease level NDVI graph from the WA Department of Primary Industries and Regional Development’s website (accessed on 29 July 2020).

 

It must be noted that seasonal NDVI is only one tool available to pastoralists and that this data should be interpreted together with other information, such as an on-ground assessment of pastures and weather forecasts.

More information about the lease level pastoral monitoring is available here.