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G. Zhelezov 2010. Evaluation of the ecosystem service in the forest formations of Biosphere Reserve “Srebarna”
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Evaluation of the ecosystem service in the forest formations of
Biosphere Reserve “Srebarna”, Northeastern Bulgaria
Georgi Zhelezov *
Institute of Geography, Bulgarian Academy of Sciences, Bulgaria
Abstract
The investigation observes the basic parameters in ecosystem services of the forest formation on
the territory of Biosphere Reserve „Lake Sreburna”. Wetland system is a part of Danube
catchments. Importance of the lake depends of rich biological and landscape diversity. The most
important are bird colonies of Dalmatian pelican and waterfowl birds.
Forest formations in the lake and around the wetland systems are natural place for nesting and
spreading of the bird populations. They are dominated of willows and popular species. The
forest formations in Danubian islands have high level of importance as quality and diversity of
the ecosystem services. They are flooded for the different period of time during the high Danube
waters. This process reflects and determines the complex of ecosystem services in the reserve.
The results of the research can use for optimization of nature protection and conservation
activities in the Biosphere Reserve „Srebarna” and the territories around the wetland system.
Keywords: ecosystem services, forest formation, evaluation
Introduction
Ecosystems provide different ecosystem services. The concept of ecosystem services deals with
the benefits that humans gain from natural processes and ecological functions (Costanza et al.
1997). Ecosystem services are supporting (nutrient cycling, soil formation, primary production
etc.), provisioning – referring to the resource supply (food, fuel, fiber, water, other goods),
regulatory (associated with climate, atmosphere, extreme events, water quality etc.) and cultural
(aestetic, spiritual, educational, recreational etc.). Publication of Millenium Ecosystem
Assessment in 2005 focused on ecosystem services of different ecosystems, stressing their
overall decline.
Forest formations are among the most endangered systems in spite of the fact that they have a
great influence on human wellbeing and are providing to us the majority of important
ecosystem services. Forest formations of Danubian island and around the lake are marked by
changes in water level during the year. Water level fluctuations create a variety of habitats with
diverse communities. Habitats are delineated by a range of changes in water regime, soil
properties and some other factors. Many primary producers are well adapted to these changes
(avoiding unfavourable conditions, being cosmopolites, having persistent stadia or amphibious
character) and find optimal conditions for their survival while supporting a variety of other
organisms. Water level during the vegetation period as well as the intensity, timing and the
extent of floods influence primary production and other processes i.e. mineralization,
decomposition, colonization with plants, as revealed from different studies. The researches
revealed that ecosystem services depend on biotic community complexity, especially on
vegetation type of the area.
* Corresponding author. Tel.: +359 2 979 6309 - Fax: +359 2 870 0204
Email address: gzhelezov@abv.bg; zhelezov75@yahoo.com
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.