Cone production of upper slope conifers in the Cascade Range of Oregon and Washington, 1959 to present

Seed supply is a key feature of tree population dynamics, and seed production may be indicative of environmental and biological drivers. This study examines cone production in upper-slope, true fir-hemlock forests of the Pacific Northwest, starting in 1959 to the present. Annual surveys of cone counts of Abies spp. (A. amabilis, A. concolor, A. grandis, A. lasiocarpa, A. magnifica, A. procera), Pinus spp. (P. engelmannii, P. lamberti, P. monticola), and Tsuga spp. (T mertsiana) have been conducted at sixty-one plots in 37 locations in nine national forests in Washington and Oregon (originally 10 national forests, but Mt. Baker and Snoqualimie were combined). At each site, a visual count is made of cone production in each of a number (20-30) trees in a stand of one tree species. At some plots, additional trees were added in the 1980s. Primary data include numbers of counts per tree per year, periodic measurements of tree diameter, and the names of the sites. These data illustrate the periodicity of cone production cycles, as well as longer trends associated with climate change and variability in the region.

种子供应是林木种群动态的核心特征之一，种子产量可反映环境与生物驱动因子的调控作用。本研究聚焦太平洋西北坡地真冷杉-铁杉林的球果产量，监测时段始于1959年并持续至今。研究团队在华盛顿州与俄勒冈州9个国家森林的37个地点内设置61块样地，对冷杉属（Abies）（含太平洋冷杉A. amabilis、科罗拉多冷杉A. concolor、大冷杉A. grandis、亚高山冷杉A. lasiocarpa、壮丽冷杉A. magnifica、高贵冷杉A. procera）、松属（Pinus）（含恩氏松P. engelmannii、糖松P. lamberti、西部白松P. monticola）以及铁杉属（Tsuga）（含北美铁杉T. mertensiana，原文存在拼写笔误为T mertsiana）的球果数量开展年度调查。在每个样地，研究人员会对单一树种林分内的20至30株样木分别开展球果产量目视计数；部分样地在20世纪80年代新增了监测样木。原始数据集包含每株样木每年的球果计数结果、周期性测定的树木直径，以及样地的相关名称信息。该数据集可用于阐明球果生产周期的周期性特征，以及该区域与气候变化和气候变异性相关的长期变化趋势。