Fire Alters Emergence of Invasive Plant Species from Soil Surface-Deposited Seeds
Fire Alters Emergence of Invasive Plant Species from Soil Surface-Deposited Seeds
复制标题
火灾改变了土壤表面沉积种子中入侵植物物种的出现
DOI：
10.1614/ws-08-170.1
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发表时间：
2009
期刊：
影响因子：
2.5
通讯作者：
M. Rinella
中科院分区：
文献类型：
--
作者：
L. Vermeire;M. Rinella
对外来植物入侵的担忧使历史火灾制度的恢复变得复杂，但人们对两者如何相互作用知之甚少。日本雀麦、斑点马甲草、俄罗斯马甲草和叶菜的种子在6个燃料负荷（100至700 g m−2）和一个不燃烧的对照下进行了火处理。用田间固化的草地模拟火灾，并利用土壤表面的热电偶建立时间-温度曲线。羽化由菌种和生长室内的燃料负荷决定。燃料负荷解释了98%的平均热剂量变化，而羽化随燃料负荷的增加而减少。与未燃烧处理相比，使用100 g m−2燃料的羽化率降低了79 - 88%，使用200 g m−2燃料的羽化率至少降低了97%。除燃料负荷为300 g m−2的斑knapweed外，所有物种的应急概率均小于0.01。结果表明，火灾极有可能通过直接导致种子死亡来破坏入侵物种的生命周期。燃料负荷与幼苗出苗之间的关系为火灾对地表沉积种子的影响提供了良好的可预测性。一场大火不太可能消灭许多入侵物种，因为它们通常会产生大量的种子，有些种子无疑会逃脱火灾。然而，在燃料负荷相对较轻的情况下，幼苗出苗率的突然减少表明，在广泛的栖息地，火灾可能是增加入侵植物种子死亡率的有效工具。命名法：日本雀科；Bromus japonicus ThunbMurr交货。斑knapweed， Centaurea maculosa Lam；俄罗斯knapweed， Acroptilon repens （L.）直流;大戟叶属植物；
Abstract Restoration of historic fire regimes is complicated by concerns about exotic plant invasions, yet little is known of how the two may interact. Seeds of Japanese brome, spotted knapweed, Russian knapweed, and leafy spurge were subjected to fire at six fuel loads (100 to 700 g m−2) and a nonburned control. Fires were simulated with field-cured grass and time–temperature profiles were developed from thermocouples at the soil surface. Emergence was determined by species and fuel load in growth chambers. Fuel load explained 98% of variation in mean heat dosage and emergence decreased with increasing fuel load across species. Emergence was reduced 79 to 88% relative to nonburned treatment with 100 g m−2 of fuel and at least 97% with 200 g m−2 of fuel. Emergence probabilities were less than 0.01 for all species but spotted knapweed with a 300 g m−2 fuel load. Results indicate high potential for fire to disrupt the life cycle of invasive species through direct seed mortality. The relationship between fuel load and seedling emergence provides good predictability of fire effects on surface-deposited seeds. A single fire is unlikely to eradicate many invasive species because they often produce abundant seeds and some will undoubtedly escape fire. However, abrupt reductions in seedling emergence with relatively light fuel loads indicate that fire may be an effective tool for increasing mortality of invasive plant seed across a broad range of habitats. Nomenclature: Japanese brome, Bromus japonicus Thunb. ex Murr.; spotted knapweed, Centaurea maculosa Lam.; Russian knapweed, Acroptilon repens (L.) DC; leafy spurge, Euphorbia esula L.