Pathogens and parasites (henceforth “pathogens”) can make up a large percentage of the biomass found in ecosystems, and therefore, their impacts on ecosystem processes should be prominent. Pathogens influence ecosystem processes by affecting the abundance or phenotype of hosts and through direct contributions to ecosystem production. However, there has been little quantitative synthesis of the relative effect sizes of these impacts on ecosystem processes. This study presents a systematic review and meta‐analysis of pathogen effects on primary production, secondary production, and biogeochemical cycles. We find that the effects of pathogens on ecosystem processes were greater where pathogens influenced host or community abundance or biomass than when they influenced phenotypes. Pathogen impacts on primary production were larger than on secondary production or biogeochemical cycles. By contrast, we detected no general differences in effect sizes across host or pathogen taxon or ecosystem type (terrestrial vs. aquatic). While we have found potential evidence of publication bias against negative results, a well‐known issue in meta‐analyses, our work nonetheless shows that the available literature under‐represents some taxa and geographic regions. To better understand the extent and magnitude of pathogen impacts on ecosystem processes, future research is needed in four areas. First, research is needed on the most understudied systems, including bacteria and viruses, as well as tropical ecosystems. A second priority is research seeking to understand how key components of ecosystem variation, including age (time of ecological continuity), productivity, and species diversity and composition, may interact to mediate pathogen impacts. Third, we suggest expanding on work examining how pathogen effects are influenced by climate change, species introductions, deforestation, and other human impacts. Fourth, we expect that host coinfection influences ecosystem processes in ways that cannot always be predicted based on studies of single infections. To enable others to build on this work, we make available the data we extracted from the literature, with the code for computing effect sizes.

中文翻译：

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寄生虫和病原体对生态系统过程的影响：定量审查

病原体和寄生虫（以下称“病原体”）可构成生态系统中生物质的很大一部分，因此，它们对生态系统过程的影响应突出。病原体通过影响宿主的丰度或表型以及对生态系统生产的直接贡献来影响生态系统过程。但是，这些影响对生态系统过程的相对影响大小几乎没有定量综合。这项研究对病原体对初级生产，次级生产和生物地球化学循环的影响进行了系统的综述和荟萃分析。我们发现，在病原体影响宿主或群落丰度或生物量的地方，病原体对生态系统过程的影响要大于对表型的影响。病原体对初级生产的影响大于对次级生产或生物地球化学循环的影响。相比之下，我们在寄主或病原体分类或生态系统类型（陆生与水生）之间未发现效应大小的一般差异。尽管我们已经发现潜在证据表明出版物偏向负面结果，这是荟萃分析中的一个众所周知的问题，但我们的工作表明，现有文献不足以代表某些分类单元和地理区域。为了更好地了解病原体对生态系统过程的影响程度和程度，需要在四个领域进行进一步的研究。首先，需要研究最缺乏研究的系统，包括细菌和病毒以及热带生态系统。第二优先事项是寻求了解生态系统变化的关键组成部分的研究，包括年龄（生态连续性的时间），生产力，物种多样性和组成，可能相互作用以介导病原体的影响。第三，我们建议扩大研究气候变化，物种引进，森林砍伐和其他人类影响如何影响病原体影响的工作。第四，我们期望宿主合并感染以无法始终基于单个感染研究来预测的方式影响生态系统过程。为了使其他人可以继续这项工作，我们提供了从文献中提取的数据以及用于计算效果大小的代码。和其他人类影响。第四，我们期望宿主共感染以无法始终基于单个感染研究预测的方式影响生态系统过程。为了使其他人可以继续这项工作，我们提供了从文献中提取的数据以及用于计算效果大小的代码。和其他人类影响。第四，我们期望宿主合并感染以无法始终基于单个感染研究来预测的方式影响生态系统过程。为了使其他人可以继续这项工作，我们提供了从文献中提取的数据以及用于计算效果大小的代码。