FOREST TYPES IN ROMANIA

Romanian forests contain a large number of tree and shrub species, occurring almost always in distinct vegetation zones. There is a latitudinal distribution of vegetation sub-zones but, more importantly, an altitudinal distribution of the vegetation zones. The three main vegetation zones in Romania are the alpine zone, the forest zone and the steppe zone. The forest zone is the largest vegetation zone and it can be divided into the following sub-zones: norway spruce sub-zone (Picea abies), beech sub-zone (Fagus silvatica), Quercus petraea sub-zone, Quercus robur sub-zone and Quercus frainetto/Q. ceris sub-zone. Exotic tree species including Pseudotsuga menziesii, Pinus strobus, Pinus nigra var. nigra, Robinia pseudoacacia (over 250,000 ha) have been widely planted throughout the country.


CONSERVATION OF FOREST GENETIC RESOURCES IN ROMANIA

In Romania, a distinction is made between the concepts of "gene pool" and "genetic resources" in genetic conservation programmes. The unit, or "carrier", of genetic information is considered to be the population. In view of its dynamic interaction with changing environmental conditions, a gene pool can be maintained over successive generations only as part of the environment in which it developed. Also, it is recognized that the original gene pool has been dynamically modified over the years by external causes (natural catastrophes, human influences etc.). We cannot restore the past, and we also cannot preserve entirely unchanged the present gene pool for the future (Cronquest 1971).

Genetic resources of trees may be conserved in situ (natural stands and seed stands) and/or ex situ (stands, provenance trials, progenies, inter and intra-specific hybrids, clone collections, seeds, pollen and vegetative reproductive materials: cuttings, sprouts, tissues and cells in in vitro cultures).

In situ conservation of forest genetic resources
One method of conserving the gene pool is through the creation of protected areas. In Romania there are now 586 units protected by resolution of the national government and local authorities. 11 national parks with an overall area of 323,900 ha have been or are in the process of being formed.

In natural forest management, the use of natural regeneration is one method which can help ensure the in situ conservation of forest genetic resources; as an example, beech forests have always been naturally regenerated in Romania.

A third method of in situ conservation (commenced in 1977 in Romania) entails the identification and maintenance of seed stands in native forests. Such seed stands have two main functions:
1. Conservation of forest genetic resources;
2. Production of seed of known origin.

In Romania there are now 2,313 seed stands covering an area of 70,176 ha (47% of area with coniferous species and 53% hardwood species). These seed stands have all been listed in the 1986 Seed Stand Catalogue of Romania.

Since 1992, conservation of forest genetic resources in Romania has been given much emphasis as a follow-up to Resolution 2 of the Ministerial Conference on the Protection of Forests in Europe (Strasbourg 1990), related to the conservation of forest genetic resources; and as follow-up to the United Nations Conference on Environment and Development (UNCED), held in Rio de Janeiro in 1992. In accordance with agreements reached in these conferences the intra-specific genetic variability must be conserved as an important component of biological diversity. Conserving the intra-specific genetic variability will help to conserve biological diversity at higher levels (species and ecosystems).

Intra-specific genetic variability is usually not uniformly distributed in a tree species' natural range, and for this reason it is important to examine the extent and the geographic distribution of such genetic variation. Complexes of specific or adaptive genes can exist in some particular ecological niches (marginal sites), the fringes of a species distribution and in isolated stands (e.g. on islands). Here, the genetic variability can be accidentally reduced by selection pressures or natural events. Such adapted populations may be extremely important for tree improvement programmes, and they are in urgent need of conservation actions.

In the absence of detailed information on the distribution of genetic variation within a species one approach for conservation is to delineate seed zones (Enescu 1974). Uniform environmental conditions and tree phenology/morphology can preliminarily help define seed zones.

Exploration, sampling and description of the genetic resources of important socio-economic forest trees species in Romania has recently been completed. Future work will focus on species of lesser present-day importance. In parallel with such efforts, standards and regulations for management and conservation of forest genetic resources will be prepared, and a database/national catalogue of forest genetic resources will be developed.

Ex situ conservation of forest genetic resources
Methods of ex situ conservation include:

1. Arboreta. This is typically the first stage in introducing exotic species. The arboreta in Romania were created in the second half of the 19th century. Unfortunately most tree species are represented only by a few trees, almost always of unknown origin, and hence these are of limited use for gene conservation.
2. Botanic Gardens. Romania has 10 botanic gardens attached to universities, and they are typically conserving a great number of native and introduced species. Three of the botanic gardens maintain seed banks, and have seed available for international exchange.
3. Populations in evaluation and improvement programmes, including:
Provenance trials where the genetic variability is tested between populations. Species under investigation include Picea abies (11 trials; 101 native and foreign provenances being tested), Abies alba (8 comparative trials; 64 native and European provenances), Pinus sylvestris (8 trials; 45 provenances), Pinus nigra (5 trials; 62 native and foreign provenances), Larix decidua (7 trials; 25 provenances), Pseudotsuga menziesii (5 trials; 64 provenances), Quercus petraea (5 experiments; 50 provenances), Quercus robur (8 trials; 33 provenances), Pinus strobus (3 trials; 32 provenances) and Fraxinus excelsior (5 trials; 24 provenances).
Testing of seed stands. Norway spruce (10 experiments with seed from 63 seeds stands).

Half-sib progeny tests in which the genetic variability at inter- and intrapopulational levels may be simultaneously studied; including Picea abies (10 trials, each testing 250 half-sib progenies from 63 populations), Fagus sylvatica and Fraxinus excelsior (5 - 7 half sib progenies from 52 native and foreign populations).
Half-sib family and clonal seed orchards : 1,004 ha of tree seed orchards have been established in Romania. These orchards contribute to the ex situ conservation of about 7,000 plus trees in the form of cloned ramets (cutting origin) and half-sib progenies.
Clone collections : Including Populus spp., Salix spp and Picea spp.

FOREST GENETIC RESOURCES MONITORING IN ROMANIA

All forest genetic resources in Romania, conserved in ex situ and in situ programmes, are being managed and monitored. Trees in these programmes will be monitored regarding both their general performance and health. Each of the stands have been described and mapped. The description, written on record cards, includes detailed information on the habitat and the vegetation.

BIBLIOGRAPHY

Boscaiu, N. 1979: L'integration phytosociologique du génofond végétal (plantes vasculaires) de la Roumanie.Documents phytosociologique, N. S. vol. IV, Lille, pp. 87 - 109

Boscaiu, N. 1982: Strategiile ecologice ale fagetelor carpatine. În: V. Preda si Boscani N. Fagetele carpatine. Semnificatia lor istorica si ecoprotectiva, Lucrarile Simpozionului din 30 - 31 mai 1979, Cluj - Napoca 1982, pp. 148 - 170

Cronquest, A. 1971: Adapt or die, Bull. Merd. Bd. Nat. Belg. 41

Enescu, Val. 1978: Conservarea resurselor genetice forestiere. În: Giurgiu, V. (ed.), Conservarea padurilor, Ed. Ceres, Bucuresti, pp. 95 - 91

Enescu, Val. et al. 1974: Zonele de recoltare a semintelor forestiere în România, Ed. Ceres, Bucuresti, 61 pp.