Indicators

There is an urgent need for the development of appropriate degradation and restoration indicators and strengthening of existing measurement and monitoring programmes (see subtopic 3).  Many existing indicators are flawed or not useful.

Given the enormous number of ecosystem properties that can be measured even for one type and location of degradation, some method to summarize these into a few key properties is clearly desirable (see Section 4.1.3.1 and 4.1.3.2.). In some cases, this is accomplished by selecting key properties that are themselves affected by contributory factors, including: net primary production which is a result of soil, weather, grazing and other factors; sediment yield which is a consequence of several finer scale erosion factors; a decline in the number of species which reflects aspects of ecosystem degradation; and many others, some for specific purposes (e.g., Hunter Jr et al., 2016). A key, common requirement for these types of indicators is that they are actual ecosystem properties and can, in principle, be measured directly.

There is also some controversial discussion on a different method for summarization of degradation properties that uses synthetic indices. These are expressed as numbers or class-membership, as with single-variable indices, but are based on some aggregation of factors. We advise against these synthetic indices. There are several reasons why these should be avoided: they are not an actual condition or process, they cannot be measured directly, and do not allow the biophysical or anthropogenic process underlying the degradation to be identified to guide restoration.