A database is only as good as the information it contains. Presently the most comprehensive planted forest data is reported in FRA 2000. However, it contains many weaknesses, particularly tree species distribution by temperate and boreal industrialized countries that differ in their opinions and definition of plantations. PFDB has introduced improvements to planted forest data, especially for developing countries, but many important essential features and elements are still lacking.
Some of the most important planted forest countries based upon planted area, China, India, Indonesia and Thailand have uncertain or weak planted forest information. For example, in China the reported annual plantings from 1950 to 2000 add to over 200 million ha while the estimated plantation area in 2000 was 45 million ha (FAO 2001b). Failures in plantation establishment, forest fires, desertification processes, lack of planted forest management etc. reduce the amount of actual planted forest areas. Plantation rotation lengths can vary from five years upwards and thus the dynamics in planted forest areas is quite different from natural forests. In statistics replanting (reforestation) and new plantings (afforestation) are only very seldom distinguished.
There exist no data about the productivity of rubber tree plantations. The information about the production of poplars is weak in PFDB. Although PFDB contains large amount of both mean annual increment and rotation length data, it is scarce for many species or lacking especially if examined at regional level. In fact the estimation of productivity, based on MAI and rotation length only, is the most uncertain but in many cases the only possible way. There exist a large amount of growth models for different planted forest species but globally their validation and use is very difficult.
One of the main advantages of the PFDB is that the information available can now be collected according to a uniform database that can be used for future development of the planted forest information system. The database also combines many different sources including the four global plantation assessments in 1965, 1980, 1990 and 2000. During the progress of FRA 2000, the most comprehensive assessment up to now, it became clear that questionnaires related to plantation areas, planting rates, age class distributions, mean annual increments, rotation lengths, purpose, ownership and production of forest plantations received few responses. The increasing importance of planted forests in global wood supply, combined with the rather weak information now available, highlights that supplementing the PFDB is urgently needed.
There are many needs to improve the planted forest information. The data collection globally has been the mandate of FAO but data from industrialized temperate and boreal zone countries have been collected through UN/ECE/FAO. This has led to different datasets being collected. In the future planted forest data needs to be consistent in all countries.
The definitions of plantations and planted forests must be harmonized. There have been varied definitions during latest decades as indicated in chapter 1.1. The work that has been done on the initiative of FAO, together with other stakeholders like IPCC, IUFRO, CIFOR and UNEP, serves as an excellent basis for harmonization of plantations and planted forests definitions. Instead of defining plantations as mainly exotic, intensively managed monocultures the wider definition of planted forests is clearly necessary.
In September 2002 in Rome, Italy, the expert meeting decided that FAO FRA definition of forest plantations is recommended for further consideration (FAO 2002b). Thus FAO is responsible for further development of plantation definition. Up to now the planted forests of industrialized countries are poorly represented in the context global forest plantations and thus also in PFDB. The plans of FAO to classify forests according to the intensity of global management and purpose would clarify greatly the situation and also data collection. The issue is further discussed by Carle and Holmgren (2003).
The new classification will allow reporting of more realistic planted forests resources. For example, Germany reports to have no plantation forests though planting has been used in the country as the most common regeneration method for centuries and even though 134,000 ha of exotic Pseudostuga menziesii plantations were reported already in 1985 (Hermann and Lavender 1999). Also Finland reports no plantations even though 25 percent of forests are planted or seeded (Parviainen 1998). Canada has planted 4.5 million ha during last decade (CCFM 2002) etc. By harmonizing the planted forest definitions reporting in industrialized and developing countries can be more realistically harmonized.
In many Asian countries large plantation areas have been reported. Especially in China and India the collection of country wise data has proven to be almost impossible. In these countries one province (China) or one state (India, Indonesia) alone contains more plantations than many other countries totally. Therefore it should be considered to collect plantation data in the largest planted forests countries by provinces or states. This also applies to USA and Canada.
The question of gross and net areas of forest plantations addressed by using reduction factors in FAO estimates during the 1990s. More research is needed to obtain a real picture of planted forest resources. FAO is providing technical support to National Forest Assessments in developing countries. Planted forest resource assessment should be one essential part of these assessments.
The present planted forest database content is a collection of information from a wide range of sources that include many different levels: books, journals, working papers, proceedings of scientific meetings, projects, questionnaire documents, country reports, consultant reports and FAO documents as forest resources assessments, outlook studies, project documents, case studies, etc. Although PFDB contains over 8000 observations it is far from complete. Therefore more work is needed in completing planted forest data.
At the moment the complete version of PFDB is available at FAO Headquarters while all the data and the enquiring form are available on CD support. CDs are useful tools to disseminate information but still do not fully allow participation of country to the exercise of collecting and compiling information.
In the future, with improvement of modern information technology, the database will be placed on the Internet. The Interface of PFDB described in chapter 3.3 allows users to view, review and analyse data content in the database. The next step is the entry of new planted forest data. Until now this has been made by and after experts’ consideration. It is suggested that in the future a filter is needed in order to guarantee the quality of new data when added to the database. In the PFDB the reliability classification has been used in all data entries.
The productivity of planted forests needs to be better documented in PFDB. Mean annual increment and rotation length data have been collected by different organizations, so continued examination of literature, connections to relevant institutes, and collection of new data can improve the PFDB.
The present PFDB contains four main tables: plantation areas, planting rates, productivity and tree species. To be able to estimate the wood supply from planted forests new dimensions of planted forest data are needed. Harvest yields from planted forests including thinning, felling and waste wood are required. PFDB could include also the production of planted forest based wood products (saw logs, veneer logs, pulp wood, other industrial wood) as well as non industrial products (fuel wood, poles, cork and tan bark). The data provided in the global outlook for future wood supply from forest plantations (FAO 2000) could be linked to the PFDB or a new outlook could be done, based on the new PFDB information.
The most suitable database for PFDB will ultimately be, Forestry Information System (FORIS) in FAO. Other databases like the FAO global information system on forest genetic resources (REFORGEN), including links to common names of planted forest tree species, are essential to PFDB. Close links are also needed to the forest fire, pest management and mangrove databases which are under development at FAO.
