Gan Jelaine Lim, Grainger Matthew James, Shirley Mark David Foster, Pfeifer Marion
School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK.
Institute of Biology, College of Science, University of the Philippines, Diliman, Quezon City, Philippines.
Environ Evid. 2023 Aug 3;12(1):15. doi: 10.1186/s13750-023-00308-z.
Forest landscape restoration (FLR), often through tree planting, is one of the priorities in many global and national initiatives for carbon offsetting as part of climate change mitigation and biodiversity conservation. However, active efforts to meet FLR objectives entail substantial costs for the procurement of planting stocks and require an experienced workforce for planting and nurturing tree seedlings. Alternatively, restoration projects can be more cost-effective and potentially may have greater biodiversity gain through assisting and accelerating natural forest regeneration. The use of perches is one of the strategies under Assisted Natural Regeneration (ANR) and is used to attract avian seed dispersers to degraded habitats for increased tree seed supply and seedling establishment. This systematic review and potential meta-analysis aim to determine the effectiveness of artificial and natural perches in promoting natural forest regeneration. Specifically, we will evaluate their effectiveness in driving seed richness, seed density, seedling richness, and seedling density. The results will synthesize available evidence on the topic, identify knowledge gaps we need filling to upscale the strategy, and inform their use in concert with other ANR strategies.
The search strategy was informed through a literature scan and discussions with stakeholders and experts. A total of eight databases, which include an organizational library and a web-based search engine, will be searched using the refined search string in English. The search string was formed using keywords corresponding to the PICO structure of the research question, and its comprehensiveness was evaluated using 10 benchmark articles. The search results will be screened by the review team (composed of a primary and at least two secondary reviewers) using the set eligibility criteria at the title and abstract level, followed by the full-text screening. The screened studies will then undergo critical appraisal using the assessment criteria based on risk of bias and methods. Data from the accepted studies will be extracted to the standard data sheet for meta-analysis. Effect size (Hedges' g) will be computed to determine whether perches are effective in increasing seed dispersal and seedling establishment in degraded sites. The effect of potential modifiers relating to the landscape will be explored via mixed models.
森林景观恢复（FLR）通常通过植树造林来实现，是许多全球和国家碳抵消倡议中的优先事项之一，作为缓解气候变化和保护生物多样性的一部分。然而，为实现森林景观恢复目标而做出的积极努力需要大量成本用于采购苗木，并且需要经验丰富的劳动力来种植和培育树苗。此外，恢复项目通过协助和加速天然林再生可能更具成本效益，并且可能带来更大的生物多样性增益。使用栖木是辅助天然更新（ANR）策略之一，用于吸引鸟类种子传播者到退化栖息地，以增加树木种子供应和幼苗定植。本系统评价和潜在的荟萃分析旨在确定人工和天然栖木在促进天然林再生方面的有效性。具体而言，我们将评估它们在增加种子丰富度、种子密度、幼苗丰富度和幼苗密度方面的有效性。研究结果将综合该主题的现有证据，确定我们为扩大该策略规模而需要填补的知识空白，并为其与其他辅助天然更新策略协同使用提供参考。
通过文献扫描以及与利益相关者和专家的讨论来确定搜索策略。将使用经过优化的英文搜索词在总共八个数据库中进行搜索，其中包括一个机构图书馆和一个基于网络的搜索引擎。搜索词由与研究问题的PICO结构相对应的关键词组成，并使用10篇基准文章对其全面性进行评估。搜索结果将由评审团队（由一名主要评审员和至少两名次要评审员组成）根据设定的纳入标准在标题和摘要层面进行筛选，随后进行全文筛选。然后，将使用基于偏倚风险和方法的评估标准对筛选出的研究进行批判性评价。将从纳入研究中提取数据到标准数据表中进行荟萃分析。将计算效应量（Hedges' g）以确定栖木在退化场地增加种子传播和幼苗定植方面是否有效。将通过混合模型探讨与景观相关的潜在调节因素的影响。
