Assessment, Conservation and Sustainable Use of Forest Biodiversity

Assessment, Conservation and Sustainable Use of Forest Biodiversity
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DIVERSITY OF VEGETATION COVER IN NORWAY SPRUCE FOREST
PLANTATIONS AND DYNAMICS AT FIRST STAGES OF SUCCESSION — A
CASE OF STUDY FROM NORTH-WEST RUSSIA
Anton V. Dorochine
Laboratory of Reforestation,
St. Petersburg Forestry Research Institute,
Saint-Petersburg, Institutskiy prospect 21,
194021 St. Petersburg, Russia
E-mail: spb330@spb.sitek.net
Keywords: Picea abies, forest plantations, stages of vegetation cover development.
Introduction
The biodiversity change as a result of clear fellings of boreal spruce forests is one of the most urgent problems
at the dynamics estimation of forest ecosystems (Hannerz and Hanell, 1996). Structural and species diversity
after fellings can raise as a result of the open space areas increase or reduction of crown density (Lee, 1993),
while the number and biomass of the majority of forest herbs and mosses are reduced (Nikvist, 1997; Olsson
and Staat, 1995). It is considered that biodiversity is better provided in the natural forests with local tree
species but it is not the same for forest plantations. Nevertheless, they play positive role for the environment as
a buffer zone protecting weak areas. The requirements for preservation of the biodiversity in forestry activity
first of all consist of creation of the conditions for various ecosystems development. Plantations are capable to
play rather positive role in biodiversity preservation and in its enrichment with new species, but however it can
not be the evidence of stand stability increase and forest ecosystem in a whole. In this respect very much
depends on the chosen technology of forest growth including maintenance, scales and degree of influence on
biogeocenoses.
Methods
The researches have carried out on 86 sites of Norway spruce forest plantations (Picea abies (L.) Karst) in
Leningrad region. The plantations were planted with the various purposes: for timber growing and for
recreation and ecological aims. All plantations were planted on clear cuttings with age less than 4-5 of drained
spruce stands. The ages of plantations were 1-70. The plantations were established using various soil
cultivation techniques: plough soil cultivation (5 different plough types were used, 3 of which built in our
institute), discrete soil cultivation (3 different mechanism types, built in our institute) and without cultivation
(served as a control). On each site the vegetation cover were described on sample plots with size of 400 sq.m.
Accuracy of measurement consist that the sites were selected very carefully for two attributes: to habitat type
(binomial drifts D2 and starved loam GM2), (Chertov, 1981) and forest initial type (Piceetum myrtillosum and
Piceetum oxalidosum). The total area of the investigated plantations were 154 ha.
Results and discussion
The research has shown that with artificial reforestation the period of forest environment restoration is
reduced. The stages of forest phytocenoses development were marked depending on features of the formation
of composition and structure of vegetation cover.
I-A stage of development (during 1-7 years) — initial. It is accompanied with sodding of sites, mass growth of
heliophilous meadow, edge-meadow, edge-ruderal and forest-meadow species. At cuttings swamping the bogforest
species are spread. In the plantations many adventive species occur which are not typical for the initial
forest types. The grass cover doesn’t have definite structure characteristic for climax or long developing forest
communities without fundamental ecotope breach. Plantations of the age of 7 are taken to the forest covered
lands in connection with crown covering.
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