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A dilemma confronts attempts to check land degradation (see Monitoring Change in Land Resources). We know that degradation is serious, that it has already had substantial adverse effects on production, and will become worse if action is not taken; but we lack objective, quantitative measurements of its extent and severity.

The LADA Project, Land Degradation Assessment for Drylands, being prepared by FAO and partners, is intended to address this dilemma. Two international planning meetings have been held (December 2000 and January 2002), and a LADA website now supplies extensive documentation. The Project is currently in the second stage of planning, to include pilot studies. Funding required for full implementation has still be be obtained.

Objectives of the Project

As first conceived, the main aims of LADA were:

Because the original request came from the Convention to Combat Desertification, LADA is restricted to the world's drylands (semi-arid and dry subhumid zones). Strengthing of national institutional capacities will be needed to achieve these aims.

However, these objectives have now been considerably widened. Assessment of the economic and social impacts of degradation, and identification of measures to check and reverse it, were added at the 2000 Workshop. Socioeconomic aspects were further emphasized at the 2002 Workshop, so that the long-term purpose is now stated to be "to identify socio-economic and environmental benefits accruing from addressing land degradation in drylands".

How can degradation be measured?

The previous assessment, GLASOD, used the approach of expert opinion: provide a map basis and a semi-quantitative framework, and ask local experts to assess degradation. This is recognized as subjective, but did achieve world coverage.

LADA now hopes to add quantitative techniques, including (Workshop 2000 Report):

It will also look at productivity changes, and how farmers respond to degradation.

Comment: will LADA succeed?

As a member of its Steering Committee, I strongly support the original objective of LADA, essentially to measure land degradation. But I am concerned that in widening the project, the essential feature may be lost. Socioeconomic impacts can only be assessed on the basis of objective and quantitative assessment, initially in purely physical terms.

In particular, the project appears reluctant to undertake the major field method of degradation assessment, monitoring changes in soil properties. This is costly, but careful stratified sampling, on the basis of soil maps, can greatly increase its efficiency.

If national survey organizations had started to measure changes in soil properties when systematic soil monitoring was first advocated, in 1991, then by now we would be getting information on how soil properties have changed over 10 years.

May 2002

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Evidence of the nature, extent and severity of land degradation is reviewed in Chapter 7, Land Degradation, of Land Resources: Now and for the Future. Problems of measuring changes in land properties are discussed in Chapter 9, Monitoring Change, and soil monitoring by national soil survey organizations on pp.33-34 of Chapter 3, Resource Survey.