Are small protected habitat patches within boreal production forests effective in conserving species richness, abundance and community composition? A systematic review
Background
In boreal zone forest management is changing and degrading forest habitats, which has caused declines in biodiversity. To mitigate these harmful effects in production forests, small-scale habitats with high biodiversity values have been protected within them. These habitats include woodland key habitats, and other small habitat patches protected by voluntary conservation actions. In this systematic review we synthesize the evidence on the value of small protected habitat patches (SPHP) within production forest landscapes for biodiversity. Review question: Are small protected habitat patches within boreal production forests effective in conserving species richness, abundance, and community composition?
Methods
Both peer-reviewed and grey literature were searched from bibliographical databases, organizational websites and internet search engines in English, Finnish, Swedish and Russian. Articles were screened at two stages (title/abstract and full text) and the validity of the included studies were assessed. Screening and validity assessment were based on predetermined criteria. After data extraction, narrative and quantitative syntheses were conducted. Influences of effect modifiers were tested, and sensitivity analyses were conducted.
Review findings
During the searches 19,458 articles were found. After duplicate removal and title/abstract screening 336 articles remained. During full text screening 41 articles were included and 35 of them (174 studies) were included in narrative synthesis. 28 articles with 127 studies had suitable data for meta-analysis. SPHPs had significantly higher species richness compared to production forests. When compared to natural forests, there was no significant difference. Forest management in areas surrounding SPHPs did not have impact on species richness of these patches. Individual abundance was significantly higher in SPHPs compared to natural or production forests. There was significantly more dead wood in SPHPs compared to production forests, but when compared to natural forests there was no significant difference. Community composition was different between SPHPs and both production and natural forests.
Conclusions
The findings of this review show that small protected patches within production forests are important part of biodiversity conservation. They cannot substitute larger protected areas but supplement the protected area network. However, there were gaps both in geographical distribution of the studies as well as in the selection of target species of the studies. Therefore, generalization of the results must be done carefully.
Keywords
Forest harvesting, Logging, Impact, Woodland key habitats, Voluntary conservation, Species richness, Species diversity, Abundance, Assemblage, Dead wood
Background
Forest harvesting is the main driver of habitat degradation and biodiversity loss in forests of the boreal zone. To mitigate harmful effects, small-scale habitats with high biodiversity values have been protected within production forests. These include woodland key habitats, and other small-scale habitat patches protected by voluntary conservation action. This article describes a protocol for a systematic review to synthesize the value of small habitat patches left within production landscapes for biodiversity. The topic for this systematic review arose from a discussion with the Finnish forestry sector and was further defined in a stakeholder workshop. Research question: Do small protected habitat patches within production forests provide value for biodiversity conservation in boreal forests? Animal, plant and fungal diversities are addressed as well as the amount of deadwood within the habitat patches as proxy indicators for biodiversity.
Methods
The literature, both peer-reviewed and grey, will be searched from bibliographical databases, organizational websites and internet search engines in English, Finnish, Swedish and Russian. Article screening will be done at two stages (title/abstract and full-text). The validity of the studies included will be evaluated against validity criteria and studies will be categorized based on their risk of bias. To describe the findings a narrative synthesis will be conducted. If there is enough quantitative data retrieved from the studies, a meta-analysis will be conducted.