Increases in understory plant cover and richness persist following restoration treatments in Pinus ponderosa forests

A combination of forest thinning followed by prescribed burning is widely applied in the western US to increase ecosystem resistance and resilience to disturbances. Understory plant community responses may be driven both by management treatments and climatic factors. Thus, responses to treatments during a 20-year megadrought have implications for the role of management in fostering adaptive capacity to climate change.
We used a network of five sites (600 plots) spanning an environmental gradient in ponderosa pine (Pinus ponderosa) forests of the American Southwest, an ecosystem that is broadly distributed and actively managed throughout the western US.  We used repeated long-term monitoring data to quantify plant community responses to treatment 1-5, 6-10, and >10 years post-implementation. Specifically, we focused on the effects of treatment and abiotic conditions on native and nonnative plant cover and species richness, and on the proportion of native species with northern (cool-me...

在美国西部，森林疏伐后结合计划性火烧的组合经营措施被广泛应用，以提升生态系统对干扰的抵抗力与恢复力。林下植物群落的响应可能同时受经营措施与气候因素共同驱动。因此，在长达20年的特大干旱期间，针对这些经营措施的响应研究，对于阐明管理手段在提升气候变化适应能力方面的作用具有重要意义。本研究依托横跨美国西南部黄松（Pinus ponderosa）林环境梯度的5个样地、共计600个样方组成的监测网络——该生态系统广泛分布于美国西部并得到积极经营管理。我们采用长期重复监测数据，量化了经营措施实施后1-5年、6-10年以及10年以上时段内的植物群落响应特征。具体而言，本研究聚焦于经营措施与非生物环境条件对本土与外来植物盖度、物种丰富度，以及具有北方（冷凉……）原生植物物种占比的影响。