Which enemies mediate distance- and density-dependent mortality of tree seeds and seedlings? A meta-analysis of fungicide, insecticide, and exclosure studies

Conspecific negative distance- and density-dependence is believed to be one of the most important mechanisms controlling forest community assembly and species diversity globally. SoilPlant pathogens, and insect and mammalian herbivores, are the most common natural enemy types that have been implicated in this phenomenon, but their relative importancegeneral effects at different plant life stages isare still unclear. Here, we conduct a meta-analysis of studies that involved robust manipulative experiments, using fungicides, insecticides, and exclosures, to assess the contributions of different natural enemy types to distance- and density-dependent effects at seed and seedling stages. We found that natural enemies cause stronger distance- and density-dependent mortality caused by natural enemies was most likely at the seedling stage than the seed stage. Fungicide treatments can change significantand was greater at higher mean annual temperatures. Seedling mortality was significantly weake...