Tradeoffs and Synergies in Tropical Forest Root Traits and Dynamics for Nutrient and Water Acquisition: Field and Modeling Advances-猫眼课题宝

DOI：

10.3389/ffgc.2021.704469

发表时间：

2021-12

期刊：

影响因子：

通讯作者：

中科院分区：

其他

文献类型：

作者：

D. Cusack;S. Addo-Danso;E. Agee;K. Andersen;M. Arnaud;S. Batterman;F. Brearley;Mark Ciochina;A. Cordeiro;C. Dallstream;Milton H. Díaz‐Toribio;Lee H. Dietterich;J. Fisher;K. Fleischer;Claire Fortunel;Lucia Fuchslueger;Nathaly R. Guerrero‐Ramírez;M. Kotowska;L. F. Lugli;C. Marín;L. A. McCulloch;J. Maeght;D. Metcalfe;R. Norby;R. Oliveira;J. Powers;Tatiana Reichert;Stuart W. Smith;Chris M. Smith‐Martin;F. Soper;Laura Toro;M. Umaña;O. Valverde‐Barrantes;M. Weemstra;Leland K. Werden;M. Wong;Cynthia L Wright;S. Wright;Daniela Yaffar

植被过程从根本上受到养分和水分供应的限制，而养分和水分的吸收是由陆地生态系统中的植物根系介导的。虽然热带森林在全球水、碳和养分循环中发挥着核心作用，但我们对根系性状对资源稀缺作出反应的权衡和协同作用知之甚少。热带树木面临着一系列独特的资源限制，岩石来源的营养物质和水分季节性控制着许多生态系统功能，营养物质与水分的可用性往往在空间和时间上分离。表征生物量、深度分布、产量和物候、形态、生理、化学和共生关系的根系性状可以预测植物获取和获取营养和水分的能力，并与蒸腾、木材生产力和叶片物候等地上过程有关。在这篇综述中，我们在文献中发现了一个新的趋势，即热带表层土壤的细根生物量和产量在贫瘠或足够湿润的土壤中最大。我们还发现了热带森林根系对资源变化的反应中有趣的悖论，值得进一步探索。例如，在资源稀缺的情况下，比根长度通常会增加，以扩大所探索的土壤体积，而在热带自然森林梯度和施肥试验中，比根长度可以随着碱阳离子可用性的增加而增加。此外，营养物质的添加，而不是减少菌根在细根的定植，如预期的那样，增加了在一些森林缺水情况下的定植率。随着时间的推移，在植被模型中纳入精细根系性状和功能的努力变得越来越复杂，然而，在强调表征养分和水分吸收速率以及碳成本的模型与强调测量根系生物量、产量和形态以响应资源可用性变化的现场实验之间存在脱节。实地研究和建模工作的紧密结合可以将细根动力学的机制研究与生态系统尺度上对养分和水循环的理解联系起来，使我们能够更好地预测热带森林-气候反馈。

Vegetation processes are fundamentally limited by nutrient and water availability, the uptake of which is mediated by plant roots in terrestrial ecosystems. While tropical forests play a central role in global water, carbon, and nutrient cycling, we know very little about tradeoffs and synergies in root traits that respond to resource scarcity. Tropical trees face a unique set of resource limitations, with rock-derived nutrients and moisture seasonality governing many ecosystem functions, and nutrient versus water availability often separated spatially and temporally. Root traits that characterize biomass, depth distributions, production and phenology, morphology, physiology, chemistry, and symbiotic relationships can be predictive of plants’ capacities to access and acquire nutrients and water, with links to aboveground processes like transpiration, wood productivity, and leaf phenology. In this review, we identify an emerging trend in the literature that tropical fine root biomass and production in surface soils are greatest in infertile or sufficiently moist soils. We also identify interesting paradoxes in tropical forest root responses to changing resources that merit further exploration. For example, specific root length, which typically increases under resource scarcity to expand the volume of soil explored, instead can increase with greater base cation availability, both across natural tropical forest gradients and in fertilization experiments. Also, nutrient additions, rather than reducing mycorrhizal colonization of fine roots as might be expected, increased colonization rates under scenarios of water scarcity in some forests. Efforts to include fine root traits and functions in vegetation models have grown more sophisticated over time, yet there is a disconnect between the emphasis in models characterizing nutrient and water uptake rates and carbon costs versus the emphasis in field experiments on measuring root biomass, production, and morphology in response to changes in resource availability. Closer integration of field and modeling efforts could connect mechanistic investigation of fine-root dynamics to ecosystem-scale understanding of nutrient and water cycling, allowing us to better predict tropical forest-climate feedbacks.

Tradeoffs and Synergies in Tropical Forest Root Traits and Dynamics for Nutrient and Water Acquisition: Field and Modeling Advances

文献摘要

相似文献