Disturbance plays an important role in plant life history strategies and has been documented as both enhancing and threatening populations of the vulnerable grass Arthraxon hispidus (Thunb.) Makino (hairy jointgrass) on the NSW north coast. Mechanical disturbance (slashing) is often used in A. hispidus conservation management, but many Australian plants are adapted to fire-based disturbance regimes. In this study we undertook a field burning experiment, along with soil seed bank sampling and germination trials, to explore how fire influences A. hispidus population dynamics in terms of plant recruitment and seed bank fluctuations. We found that winter burning strongly promoted A. hispidus spring germination without entirely depleting the residual seedbank. Although drought affected our field study population, burning also led to increased adult cover and substantial seed bank replenishment the following autumn. Exposure to a smoke treatment almost doubled the germination rate of A. hispidus seeds in nursery trials. Our study suggests that appropriate burning regimes can help to maintain this species in the landscape, by both structural and chemical mechanisms, by enhancing plant recruitment and facilitating seed bank accumulation. However, some A. hispidus plants also successfully germinated, established, and reproduced in unburnt plots during our study, suggesting that populations of this species can persist without disturbance in some habitats, such as native wetland communities. We found that A. hispidus has a multi-year seed longevity and a persistent seed bank, providing the species a degree of resilience in the event of unpredictable disturbance regimes and climatic anomalies.

中文翻译：

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火能促进受威胁的一年生草茎节螟的萌发、补充和种子库积累

干扰在植物生命史策略中起着重要作用，并且已被记录为增强和威胁新南威尔士州北海岸易受伤害的草节螟（Thunb.）牧野（多毛节草）的种群。机械干扰（砍伐）常用于 A. hispidus 保护管理，但许多澳大利亚植物适应以火为基础的干扰制度。在这项研究中，我们进行了田间燃烧实验，以及土壤种子库采样和发芽试验，以探讨火灾如何在植物补充和种子库波动方面影响 A. hispidus 种群动态。我们发现冬季燃烧强烈促进了 A. hispidus 春季发芽，而不会完全耗尽剩余的种子库。尽管干旱影响了我们的实地研究人群，燃烧还导致成虫覆盖增加，并在接下来的秋天大量补充种子库。在苗圃试验中，接触烟雾处理几乎使 A. hispidus 种子的发芽率翻了一番。我们的研究表明，适当的燃烧制度可以通过结构和化学机制，通过增强植物补充和促进种子库积累来帮助维持该物种在景观中。然而，在我们的研究期间，一些 A. hispidus 植物也在未烧毁的地块中成功发芽、建立和繁殖，这表明该物种的种群可以在某些栖息地（例如原生湿地群落）中不受干扰地持续存在。我们发现 A. hispidus 具有多年的种子寿命和持久的种子库，