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? 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. 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. 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.

中文翻译：

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北方生产林中受保护的小片栖息地是否有效地保护了物种的丰富性，丰富性和群落组成？系统评价

在北方地区，森林管理正在发生变化，森林生境退化，导致生物多样性下降。为了减轻生产林中的这些有害影响，在其中保护了具有高生物多样性价值的小规模生境。这些栖息地包括林地主要栖息地，以及受自愿保护行动保护的其他小型栖息地。在这项系统的综述中，我们综合了有关生产性森林景观中小型保护性栖息地斑块（SPHP）对于生物多样性的价值的证据。审查问题：北方生产林中受保护的小型栖息地斑块是否有效地保护了物种的丰富性，丰富性和社区组成？从书目数据库，组织网站和互联网搜索引擎中以英语搜索经过同行评审的文献和灰色文献，芬兰文，瑞典文和俄文。在两个阶段（标题/摘要和全文）对文章进行了筛选，并对纳入研究的有效性进行了评估。筛查和有效性评估均基于预定标准。提取数据后，进行叙述和定量综合。测试了效果调节剂的影响，并进行了敏感性分析。在搜索中，找到19,458篇文章。重复删除和标题/摘要筛选后，剩余336条。在全文筛选期间，纳入了41篇文章，其中35篇（174篇研究）被包括在叙事综合中。包含127个研究的28篇文章都有适合进行荟萃分析的数据。与生产林相比，SPHP具有更高的物种丰富度。与天然林相比，没有显着差异。SPHPs周围地区的森林管理对这些斑块的物种丰富度没有影响。与天然林或生产林相比，SPHP中的个体丰度明显更高。与生产林相比，SPHP中的死木显着多，但与天然林相比没有显着差异。SPHP与生产林和天然林之间的社区组成有所不同。这次审查的结果表明，生产林中受保护的小块土地是生物多样性保护的重要组成部分。他们不能替代较大的保护区，但可以补充保护区网络。但是，研究的地理分布以及研究目标物种的选择都存在差距。因此，