RUI: Oak Regeneration: Roles for Fungi and Small Mammals

RUI：橡树再生：真菌和小型哺乳动物的作用

• 批准号: 0516229
• 负责人: Darlene Southworth
• 金额: $ 32.07万
• 依托单位: Southern Oregon University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-15 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0516229&HistoricalAwards=false
• 关键词: RUI; Oak; Regeneration; Roles; Fungi

Natural regeneration in oaks, particularly Oregon white oak, is poor. Few seedlings grow beyond a few years; saplings are rare. Oak roots depend on beneficial fungi in the form of mycorrhizas, modified roots that form a symbiotic association between the oak trees and the fungi. Fungi provide water and nutrients to trees; trees provide sugars to fungi. Many mycorrhizal fungi are species of truffles. Their spores cannot be dispersed by air because the fruiting bodies remain closed underground. So the problem for the oaks is two-fold: acorns must be dispersed away from the parent tree to avoid competition, and they require fungi to make mycorrhizas. One possibility is that small mammals eat the truffles and disperse the spores. The goal of this proposal is to determine the roles of fungi and small mammals in oak regeneration. The objectives are to (1) assess the availability of fungi for mycorrhizal formation at distances away from mature oaks; (2) measure the effect of absence of fungal sources on seedling growth, and (3) determine the potential of small mammals to disperse mycorrhizal fungi.The broader impacts of the proposed work include (1) engaging undergraduate students in research and (2) collaboration with land managers to preserve and regenerate oak habitat. Students will be responsible for parts of the project, and will present their work at scientific meetings. The PIs will communicate with applied scientists in environmental organizations and federal agencies, and with private land owners, attending meetings and conferences. They will give talks and provide handouts about oak ecology and management of oak habitat.

橡树，特别是俄勒冈州白色橡树的自然再生很差。很少有幼苗能生长超过几年;树苗是罕见的。橡树的根依赖于以菌根形式存在的有益真菌，这些菌根是在橡树和真菌之间形成共生关系的改良根。真菌为树木提供水分和养分;树木为真菌提供糖分。许多菌根真菌是块菌的种类。它们的孢子不能通过空气传播，因为子实体保持封闭在地下。因此，橡树面临的问题是双重的：橡子必须远离母树以避免竞争，它们需要真菌来产生菌根。一种可能性是小型哺乳动物吃了松露并传播孢子。这项建议的目标是确定真菌和小型哺乳动物在橡树再生中的作用。目的是（1）评估在远离成熟橡树的距离上真菌菌根形成的可用性;（2）测量不存在真菌源对幼苗生长的影响，以及（3）确定小型哺乳动物传播菌根真菌的潜力。拟议工作的更广泛影响包括（1）吸引本科生参与研究和（2）与土地管理者合作，保护和再生橡树栖息地。学生将负责该项目的部分，并将在科学会议上介绍他们的工作。PI将与环境组织和联邦机构的应用科学家以及私人土地所有者进行沟通，参加会议和会议。他们将发表演讲，并提供有关橡树生态和橡树栖息地管理的讲义。