Fire modifies plant–soil feedbacks
Fire modifies plant–soil feedbacks
复制标题
火灾改变了植物和土壤的反馈
DOI：
10.1002/ecy.3994
复制
发表时间：
2023
期刊：
影响因子：
4.8
通讯作者：
Brudvig, Lars A.
中科院分区：
文献类型：
--
作者：
Warneke, Christopher R.;Yelenik, Stephanie G.;Brudvig, Lars A.
虽然植物-土壤反馈（植物和土壤之间的相互作用，通常由土壤微生物介导，缩写为PSFs）被广泛认为会影响当地和景观尺度的植物多样性模式，但这些相互作用很少在重要的环境因素中进行研究。解决环境因素的作用是很重要的，因为环境背景可能会改变PSF模式，通过修改某些物种的强度甚至方向的PSF。一个重要的环境因素，是增加规模和频率与气候变化是火灾，虽然火灾对PSF的影响仍然基本上没有检查。通过改变微生物群落组成，火灾可能会改变可用于定植植物根部的微生物，从而改变火灾后的幼苗生长。这有可能改变PSF的强度和/或方向，这取决于微生物群落组成的这种变化如何发生以及微生物与之相互作用的植物物种。我们研究了最近的一场火灾如何改变夏威夷两种豆科固氮树种的PSF。对于这两个物种，在同种土壤中生长导致更高的植物性能（生物量生产测量）比在异种土壤中生长。这种模式是由根瘤形成介导的，根瘤形成是豆科植物生长的一个重要过程。火灾削弱了这些物种的PSF，因此成对的PSF在未燃烧的土壤中很显着，但在燃烧的土壤中不显着。理论表明，在未燃烧的地点发现的正的PSF会加强物种的优势，因为它们在当地占优势。烧伤状态下成对PSF的变化表明PSF介导的优势可能在火灾后减弱。我们的研究结果表明，火灾可以通过削弱豆科植物根瘤菌共生，这可能会改变两个冠层优势树种之间的局部竞争动态修改PSF。这些发现说明了在评估植物的PSF的作用时考虑环境背景的重要性。
Although plant–soil feedbacks (interactions between plants and soils, often mediated by soil microbes, abbreviated as PSFs) are widely known to influence patterns of plant diversity at local and landscape scales, these interactions are rarely examined in the context of important environmental factors. Resolving the roles of environmental factors is important because the environmental context may alter PSF patterns by modifying the strength or even direction of PSFs for certain species. One important environmental factor that is increasing in scale and frequency with climate change is fire, though the influence of fire on PSFs remains essentially unexamined. By changing microbial community composition, fire may alter the microbes available to colonize the roots of plants and thus seedling growth post‐fire. This has potential to change the strength and/or direction of PSFs, depending on how such changes in microbial community composition occur and the plant species with which the microbes interact. We examined how a recent fire altered PSFs of two leguminous, nitrogen‐fixing tree species in Hawaiʻi. For both species, growing in conspecific soil resulted in higher plant performance (as measured by biomass production) than growing in heterospecific soil. This pattern was mediated by nodule formation, an important process for growth for legume species. Fire weakened PSFs for these species and therefore pairwise PSFs, which were significant in unburned soils, but were nonsignificant in burned soils. Theory suggests that positive PSFs such as those found in unburned sites would reinforce the dominance of species where they are locally dominant. The change in pairwise PSFs with burn status shows PSF‐mediated dominance might diminish after fire. Our results demonstrate that fire can modify PSFs by weakening the legume‐rhizobia symbiosis, which may alter local competitive dynamics between two canopy dominant tree species. These findings illustrate the importance of considering environmental context when evaluating the role of PSFs for plants.