LTREB: Oak Mast as a Keystone Resource in Forest Community Dynamics

LTREB：橡树桅杆作为森林群落动态的关键资源

• 批准号: 9306641
• 负责人: Jerry Wolff
• 金额: $ 5.02万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-07-15 至 1996-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9306641&HistoricalAwards=false
• 关键词: LTREB; Oak; Mast; Keystone; Resource

9306641 Wolff Results from a 13-year study conducted at the Mountain Lake Biological Station in the southern Appalachian Mountains suggests a dynamic interaction between mast production and primary and secondary consumers. Episodic mast production has resulted in population fluctuations of mice, chipmunks, and other mast consumers. Carnivores, primarily barred owls, exhibit a numerical response to rodent densities. Seed survival and germination occurs only during peak mast production years and seedling mortality is associated with deer browsing activity. Chipmunks appear to be the major predators on ground nesting birds, and their densities are inversely correlated with junco fledgling success. This project will continue the monitoring of the major players in these trophic levels for two years to determine the direct and indirect effects of episodic mast production on selected primary and secondary consumers, seed survival and forest regeneration, and community stability in a southern Appalachian deciduous forest community. Specifically the project will (1) determine the role of mast production in regulating population densities of three seed-eating rodent species, white-footed mice, deer mice, and chipmunks, (2) determine if and how fluctuating rodent densities affect seed survival and germination rates, and fledgling success of ground nesting birds, primarily juncos, (3) test the predator-satiation hypothesis for seed masting in deciduous oaks, (4) determine the role of deer browsing on survival and growth of understory vegetation, and (5) provide baseline data on these aspects of the community structure and dynamics prior to the anticipated invasion of gypsy moths. %%% Research projects of this type are especially important to the understanding of the complex interactions of populations comprised by the forest ecosystem. Results from the work should yield fundamental insights on species interactions as well s provided information applicable to the be tter management of forest resources. ***

小行星9306641 在阿巴拉契亚山脉南部的山湖生物站进行的一项为期13年的研究结果表明，桅杆生产与初级和次级消费者之间存在动态相互作用。 间歇性肥大产生导致小鼠、花栗鼠和其他肥大消费者的种群波动。 食肉动物，主要是横斑猫头鹰，对啮齿动物密度表现出数字反应。 种子存活和发芽只发生在肥大细胞生产高峰年和幼苗死亡率与鹿浏览活动。 花栗鼠似乎是地面筑巢鸟类的主要捕食者，它们的密度与junco羽翼未丰的成功呈负相关。 该项目将继续监测这些营养水平的主要参与者两年，以确定在阿巴拉契亚南部落叶林群落中，对选定的初级和次级消费者，种子存活和森林再生以及群落稳定性的直接和间接影响。 具体来说，该项目将（1）确定肥大细胞在调节三种食种子啮齿动物物种（白足鼠、鹿鼠和金花鼠）的种群密度中的作用，（2）确定啮齿动物密度的波动是否以及如何影响种子存活率和发芽率，以及地面筑巢鸟类（主要是容科斯）的雏鸟成功，（3）验证落叶栎种子肥大的捕食者-饱腹假说;（4）确定鹿的取食对林下植被生存和生长的作用;和（5）在舞毒蛾预期入侵之前，提供有关群落结构和动态的这些方面的基线数据。 这类研究项目对于理解森林生态系统中种群之间复杂的相互作用尤为重要。 这项工作的结果将产生关于物种相互作用的基本见解，并为森林资源的更好管理提供信息。 ***