From the outline given in Section 2 of this report, it is evident that the various criteria and indicator processes have taken a variety of approaches to the issue of monitoring conservation of genetic diversity in forests. Some processes specify quantitative indicators and others have defined qualitative indicators. Some are pitched at the national level and others aim to cover both national and sub-national levels. Some attempt to use direct quantitative data and others use surrogate attributes of genetic diversity.
Perusal of the indicators shows that in most cases they address only a small part of the overall genetic diversity in forest ecosystems. Some focus only on rare, threatened and endangered species. While these species are important in their own right, they may not provide a realistic picture of what is happening in the forest as a whole, especially at the national level.
Some processes take a rather restrictive view of genetic diversity, and do not explicitly encompass all kinds of forest- natural, planted and trees grown in agroforestry systems. All of these have important roles to play in the conservation of forest biological diversity. As it becomes more widely accepted that conservation of biological diversity is not just a matter of setting up forest preserves, but that diversity in general, and genetic diversity in particular, must be carefully managed, a more holistic approach is necessary (Palmberg-Lerche, 2002).
It is clear then, that many of the genetic diversity indicators in current criteria and indicator processes are not effective, or lack practicality. Perhaps this is to be expected at the current stage of development of the indicator concept in respect of genetic diversity. The field is at the frontier of current science and a great deal more research is necessary before more effective indicators can be formulated. However, as yet there is not a great deal of progress in this direction. Comments from some of the workers in this field indicate that a strong impetus for research is currently lacking. Some processes have effectively relegated the genetic diversity issue to the “too hard to tackle basket”.
The approach taken by some national level processes, of prescribing quantitative indicators for genetic diversity, does not seem appropriate, and needs review. At the sub-national or FMU level, it seems much more sensible to try to use quantitative indicators, provided that the scientific concerns can be overcome. At the national level, the critical issue is whether there are adequate mechanisms in place to conserve forest genetic diversity. The situation will obviously vary with the size of the country. While it may be sensible to apply national level mechanisms in a small country like New Zealand, it would be unworkable to do so in a vast country like Russia.
While they are attractive in theory, direct quantitative measures of genetic diversity using biochemical techniques have a number of conceptual constraints:
- our inability to correlate biochemical genetic data with field performance of an organism,
- the cost and resource requirements for biochemical genetic monitoring,
- the unresolved sampling issues attached to direct quantitative indicators,
- problems in interpretation of data from one or few organisms in relation to sustaining the genetic constitution of a whole forest ecosystem,
- the unresolved issue of threshold or baseline values.
In view of these difficulties, there appears to be a general trend away from direct quantitative indicators of genetic diversity, reflected in a decline in the number of publications on the issue in the last 2-3 years, and a move toward surrogate indicators that assess the maintenance of the ecological processes that drive forest biological diversity. Even with surrogate attributes, the problem of interpretation remains. How we interpret information on any aspect of genetic diversity, in the context of sustainable forest management, is still largely unexplored territory.
No criteria and indicator process currently uses direct biochemical techniques to assess genetic diversity. This situation seems unlikely to change in the near future, unless there are marked technological advances that increase the relevance and at the same time reduce the cost of such techniques. However, even if this were to happen, there will still be a practical problem to adoption of a biochemical approach, if there is a constant threat that a particular procedure adopted becomes technologically obsolent. According to Glaubitz and Moran (2000), there is rapid development in biochemical genetic techniques at the present time. The whole essence of an indicator system is the ability to be able to make a time series comparison, so that trends in attributes of significance to sustainable forest management can be detected. If biochemical techniques are constantly changing, valid time series analyses would be difficult, if not impossible.
For this reason, and because of the associated difficulties in sampling and making links between a biochemical feature and a field characteristic that has relevance to sustainability, the best use of biochemical methods appears to be in supporting research. A good example of their use in this way is the DENDROGENE project in Brazil (Kanashiro et al, 2001). This innovative project is using biochemical methods to study the effect of various management interventions on genetic diversity, and modeling the results to estimate long term effects of any changes. While the intended end point is new or modified guidelines for forest management, the approach might equally well be used to evolve effective genetic diversity indicators.
Some processes are continuing to work on the use of keystone species to assess changes in overall genetic diversity over time. This approach also seems to be encountering some conceptual problems. There is always the danger that one falls back on currently available data, which, while having the virtue of being available now, may well not tell us anything at all about the status and trends in genetic diversity of the forest ecosystem. Long term datasets presently available will often refer to a charismatic species, such as the tiger or gorilla, or organisms of wide general public interest, such as birds, which, although important in themselves, are not as important as indicators for the sustainable functioning of a forest ecosystem as, say, changes in the occurrence of mycorrhizae.
