EAGER: Quantifying the effects of a fungus-mediated termite and bark beetle interaction on wood decomposition.

EAGER：量化真菌介导的白蚁和树皮甲虫相互作用对木材分解的影响。

• 批准号: 1660346
• 负责人: John Riggins
• 金额: $ 22.75万
• 依托单位: Mississippi State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-01 至 2021-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1660346&HistoricalAwards=false
• 关键词: EAGER; Quantifying; effects; fungus; mediated

The health, conservation and management of forests depends on accurate models predicting the rate at which trees die and decompose. Currently, such models assume the rate at which dead wood decomposes is primarily a function of the temperature, tree type and available moisture. Recent evidence suggests that wood-consuming decomposer organisms may be nearly as important in determining the rate of wood decay as these environmental factors. Bark beetle infestations in forests generate massive amounts of dead wood during outbreaks. During bark beetle epidemics, termites create biological hotspots in and around the dead trees in which they feed. This, in turn, influences the abundance and diversity of subsequent decomposer organisms. Preliminary findings from a forest in in the Southeastern USA indicate that fungi carried to trees by bark beetles increase the rate at which termites consume wood containing these fungi. This EAGER project will use intense field studies to determine whether the interaction between bark beetles, fungi and termites is widespread in other forests in North and South America. This discovery may help solve a critical need to understand why dead wood in forests often decomposes at more variable rates than expected based on temperature. The project will include training opportunities at the undergraduate and graduate levels. As part of the project, a permanent termite display will be constructed at the Mississippi Entomological Museum, and project findings will be disseminated via a popular social media webpage.The objective of this project is to experimentally quantify the importance of this newly-discovered fungus-mediated interaction between bark beetles and subterranean termites on wood decomposition rates in a wide array of coniferous forests (tropical, subtropical, and arid) that contain ongoing bark beetle epidemics and three distinct levels of subterranean termite abundance and diversity. Three field sites will be established, each with an experiment that manipulates presence/absence of the fungus and subsequently quantifies differences in composition of the decomposer communities and rate of wood decay. Meteorological data (temperature, precipitation), termite and other woodboring insect abundance and diversity, fungal community data, wood and soil heterotrophic respiration data, and wood decomposition data we be collected at each site. In this way, this study will determine the relative importance of this biological interaction in mediating wood decomposition across a variety of climactic zones. Ecosystem processes such as decomposition are currently treated as a black box in models, with little focus on interactions among decomposers. The recently discovered link between two ecosystem engineers (bark beetles and termites) may be a significant driver of carbon fluxes in many forest ecosystems, and therefore may have significant impact on the future conceptual frameworks employed to quantify and model wood decomposition rates.

森林的健康、保护和管理取决于预测树木死亡和分解速度的准确模型。目前，这些模型假设枯木分解的速度主要是温度、树木类型和可用水分的函数。最近的证据表明，在决定木材腐烂速度方面，消耗木材的分解生物可能几乎与这些环境因素一样重要。树皮甲虫在森林中肆虐，在爆发期间产生大量的枯木。在树皮甲虫流行期间，白蚁在它们赖以为生的死树内部和周围制造生物热点。这反过来又影响了随后的分解者生物的丰度和多样性。美国东南部森林的初步调查结果表明，树皮甲虫携带到树上的真菌增加了白蚁消耗含有这些真菌的木材的速度。这个EAGER项目将利用密集的实地研究来确定树皮甲虫、真菌和白蚁之间的相互作用是否在北美和南美的其他森林中广泛存在。这一发现可能有助于解决一个关键的需求，即理解为什么森林中的枯木通常以比基于温度的预期更可变的速率分解。该项目将包括本科生和研究生两级的培训机会。作为项目的一部分，将在密西西比昆虫博物馆建造一个永久性的白蚁展览，项目发现将通过一个流行的社交媒体网页传播。该项目的目的是通过实验量化这种新发现的树皮甲虫和地下白蚁之间真菌介导的相互作用对广泛针叶林（热带、亚热带和干旱）木材分解率的重要性，这些针叶林包含持续的树皮甲虫流行和地下白蚁丰度和多样性的三个不同水平。将建立三个实地地点，每个地点都有一个实验，操纵真菌的存在/不存在，然后量化分解者群落组成和木材腐烂率的差异。采集各站点的气象数据（温度、降水）、白蚁等蛀木昆虫丰度和多样性、真菌群落数据、木材和土壤异养呼吸数据以及木材分解数据。通过这种方式，本研究将确定这种生物相互作用在各种气候带中介导木材分解的相对重要性。诸如分解之类的生态系统过程目前被视为模型中的黑箱，很少关注分解者之间的相互作用。最近发现的两个生态系统工程师（树皮甲虫和白蚁）之间的联系可能是许多森林生态系统中碳通量的重要驱动因素，因此可能对未来用于量化和模拟木材分解率的概念框架产生重大影响。

项目成果

Termite Presence and Feeding on Loblolly Pine Wood Differs Among Four Root-Infecting Bluestain (ophiostomatoid) Fungal Species

火炬松木材上白蚁的存在和取食在四种感染根部的蓝斑（蛇口类）真菌物种中存在差异

• DOI: 10.1093/ee/nvab052
• 发表时间: 2021
• 期刊: Environmental Entomology
• 影响因子: 1.7
• 作者: Clay, Natalie A;Siegert, Courtney;Tang, Juliet D;Little, Nathan S;Eckhardt, Lori G;Riggins, John J
• 通讯作者: Riggins, John J

Indirect effects of bark beetle-generated dead wood on biogeochemical and decomposition processes in a pine forest

树皮甲虫产生的死木对松林生物地球化学和分解过程的间接影响

• DOI: 10.1007/s00442-018-4283-3
• 发表时间: 2018
• 期刊: Oecologia
• 影响因子: 2.7
• 作者: Siegert, Courtney M.;Clay, Natalie A.;Tang, Juliet D.;Garrigues, Lisa G.;Riggins, John J.
• 通讯作者: Riggins, John J.

Biogeochemical hotspots around bark-beetle killed trees

树皮甲虫杀死树木周围的生物地球化学热点

• 发表时间: 2018
• 期刊: Proceedings of the 19th biennial southern silvicultural research conference
• 作者: Siegert, CM