Growth of Tropical Bracken (Pteridium arachnoideum): Response to Weather Variations and Burning
Growth of Tropical Bracken (Pteridium arachnoideum): Response to Weather Variations and Burning
复制标题
热带蕨菜（Pteridium arachnoideum）的生长：对天气变化和燃烧的反应
DOI：
10.1614/ipsm-d-09-00031.1
复制
发表时间：
2010
影响因子：
13.5
通讯作者：
E. Beck
中科院分区：
文献类型：
--
作者：
Kristin Roos;R. Rollenbeck;T. Peters;J. Bendix;E. Beck
摘要热带蕨菜生长于热带地区，其生态学研究尚不十分清楚。我们研究了它对厄瓜多尔南部安第斯山脉天气变化和燃烧的反应，在那里，这种杂草已经长满了40%的牧场。在野外观察中，一个恒定的1：1的比率新兴和垂死的叶片建议限制叶片密度的养分短缺。这一比例的短期偏差可能与天气变化有关。干旱的天气暂时增加了死亡率，但刺激了新叶子的出现。火灾后立即产生的叶状体的寿命比未受影响的蕨生长过程中产生的寿命长。在最初的2至3个月期间，观察到突发的叶状体发展火灾后，随后自疏到一个稳定的水平。为了分析火对蕨菜的影响，用热脉冲处理根茎。根状茎耐热高达70 ℃，从短枝和叶生产提高了温度。燃烧显然释放顶端优势的发达的叶子，因为没有切割，并刺激萌芽。在厄瓜多尔，当地的牧场维护做法是反复燃烧，这有利于蕨类植物的生长。学名：Bracken，Pteridium aquilinum agg.（L.）Kuhn;热带蕨（南半球的蕨），例如，新热带蕨Maxon和Pteridium caudatum（L.）Maxon
Abstract The ecology of tropical bracken, which occurs in tropical regions, is not well known. We studied its response to weather variations and burning in the south Ecuadorian Andes, where this weed had already overgrown 40% of the pastureland. In field observations, a constant 1 : 1 ratio of emerging and dying leaves suggested limitation of frond density by nutrient shortage. Short-term deviations from that ratio could be related to weather variations. Spells of dry weather temporarily increased mortality but stimulated emergence of new fronds. Lifespan of the fronds produced immediately after a fire was longer than of those produced during unaffected bracken growth. A burst of frond development during the initial 2 to 3 mo was observed after a fire followed by self-thinning to a stable level. To analyze the effect of fire on bracken, rhizomes were treated with heat pulses. Rhizomes were heat tolerant up to 70 C, and frond production from short shoots was enhanced by elevated temperature. Burning apparently releases apical dominance of developed fronds, as does cutting, and stimulates bud break. The local practice of pasture maintenance in Ecuador of repeated burning favors growth of the fern. Nomenclature: Bracken, Pteridium aquilinum agg. (L.) Kuhn; tropical bracken (bracken of the southern hemisphere), e.g., neotropical Pteridium arachnoideum (Kaulf.) Maxon and Pteridium caudatum (L.) Maxon