Table 3 Summary of lessons learnt

1

Cost benefit analysis (CBA)

Rehabilitation warranted if direct benefits exceed costs.

CBA is invalid in this context. Rehabilitation is forever, therefore requires discounting, but there is no single right discount rate. Also, natural capital is hard to price and is indispensable, irreplaceable and non-substitutable.

CBA is unsuited to deciding whether or not to rehabilitate. Need a more definitive criterion than cost.

2

Value neutral science and technology

Science and technology inform us on whether or not to rehabilitate.

How the world should be is not derivable from how the world is.

Guidance sought - whether or not to rehabilitate - is not given by science and technology but depends on value judgement.

3

Rehabilitation standard

Standard to which rehabilitation done is conditional, e.g. nature of degradation, future intended land use, affordability.

Where rehabilitation is legally required it is easier to apply law all than only some of the time. All are equal before the law. Even only occasional incomplete rehabilitation will run down natural capital. The pre-existing land capability, not the future intended land use, is relevant. To the reluctant rehabilitator, no rehabilitation is affordable.

Rehabilitation must always be done to the same standard which is to put it back like it was, i.e. the high standard (Lesson 4).

4

Sustainable rehabilitation

Meet the needs of the present without compromising the ability of future generations to meet their own needs.

There are two objectives and they are liable to conflict. The needs and wants of future generations are uncertain. Guidance is not given on how to proceed.

Restore so that environment looks and functions as it previously did, without bequeathing any maintenance or land management more than is needed for adjoining similar but undisturbed land.

5

Rehabilitation criteria

Unclear what constituted good rehabilitation and how it might be distinguished from poor rehabilitation.

Was not possible to proceed without a perspective which required observation, data and testing ideas.

Need one objective with boundary conditions (the criteria) that define what rehabilitation must achieve and can be represented by simple powerful metrics.

6

Measurement

Adopt the convention in science of repeatability, whatever it takes.

Just any type of measurement is not enough. Measurement must be designed to go beyond science’s repeatability, and meet a range of needs and applications.

Nest of interrelated requirements – simple, understandable, informative, workable, objective, consistent, reliable, economic, credible to the stakeholders, formalized into exact algorithms, enable benchmarking, and yield a decision trail.

7

Rehabilitation design

Use CBA and follow conventional agricultural and soil conservation design to limit soil erosion and re-establish native biodiversity.

CBA is unworkable (Lesson 1). Berms and other conservation structures require maintenance, create long-term liabilities, and pass on cost (or reduced benefit) to future generations, and therefore conflict with sustainability. It is not possible to establish and sustain native biodiversity on unstable landscapes.

Rehabilitation is not primarily to stop soil erosion and establish native vegetation. At best, these are necessary but insufficient goals. Begin with end in mind. Design a durable rehabilitation product with low slope, drainage, concave footslope, smooth surface, meets required land capability, and limits long-term liabilities.

8

Environmental function

Rely on secondary succession to establish a plant cover to protect against soil erosion, and at the same time restore climax vegetation and native biodiversity.

Secondary succession by itself is slow and incomplete and fails to restore pre-existing environmental function within relevant time spans.

Initial focus is on restoring soil and thereby environmental function. Need earthy material, fertilizer, fertilizer-responsive grasses, iterated fertilize-grow-defoliate, and use cattle to promote nutrient cycling.

9

Innovation

Tightening regulation raises rehabilitation cost and deters high-standard rehabilitation.

Technology, products, processes and customer needs are not fixed/static, but can and do change.

Innovate to improve rehabilitation standard, run down cost, limit long-term liabilities and build company and national competitiveness.

10

Leadership

Usually rehabilitation is not core business, so only good practice and compliance with the law adopted.

Following not leading means trailing state-of-the-art, being vulnerable to green intervention and unrealistic prescription. Failure to pursue efficiency relentlessly.

Business and government should be proactive, developing standards, how to achieve them, designing simple powerful metrics, measuring performance, reporting and committing to continuous improvement.