Algal defenses, population stability, and the risk of herbivore extinctions: a chemostat model and experiment
Algal defenses, population stability, and the risk of herbivore extinctions: a chemostat model and experiment
复制标题
藻类防御、种群稳定性和草食动物灭绝的风险：恒化器模型和实验
DOI：
10.1007/s11284-009-0596-3
复制
发表时间：
2009
影响因子：
2
通讯作者：
W. Mooij
中科院分区：
文献类型：
--
作者：
I. V. D. Stap;M. Vos;B. Kooi;B. Mulling;E. Donk;W. Mooij
在以轮虫为捕食者、不同藻株为猎物的淡水浮游生物系统中，研究了诱导型防御和组成型防御对浮游生物种群动态的影响。我们使用恒化器的捕食者-被捕食者模型对这些系统进行了预测，并重点研究了种群稳定性和捕食者持续生存性随流量的变化。该模型在高营养盐浓度下表现出三种主要的行为类型：（1）在高稀释率下，只有藻类存在;（2）在中等稀释率下，藻类和轮虫稳定共存;（3）在低稀释率下，出现大的种群波动，低的最小密度带来随机轮虫灭绝的风险。参数空间中相应区域的大小和位置主要取决于藻类防御策略的类型。在83天的高营养恒化器实验中，我们每3周改变一次稀释率，从每天0.7到0.5到0.3到0.1。在此稀释率范围内，轮虫和藻类共存，藻类的种群波动明显增加稀释率降低。在低稀释率下，食草动物密度的变异系数在实验结束时最大。在第80天，在所有三个具有永久防御藻类的恒化器中（轮虫密度已经很低），以及在轮虫以具有诱导防御的藻类为食的三个恒化器中的两个恒化器中（代表更多可食用的食物），食草性轮虫已经无法检测到。我们解释我们的结果与丰富的悖论。
The effects of inducible defenses and constitutive defenses on population dynamics were investigated in a freshwater plankton system with rotifers as predators and different algal strains as prey. We made predictions for these systems using a chemostat predator–prey model and focused on population stability and predator persistence as a function of flow-through rate. The model exhibits three major types of behavior at a high nutrient concentration: (1) at high dilution rates, only algae exist; (2) at intermediate dilution rates, algae and rotifers show stable coexistence; (3) at low dilution rates, large population fluctuations occur, with low minimum densities entailing a risk of stochastic rotifer extinctions. The size and location of the corresponding areas in parameter space critically depend on the type of algal defense strategy. In an 83-day high-nutrient chemostat experiment we changed the dilution rate every 3 weeks, from 0.7 to 0.5 to 0.3 to 0.1 per day. Within this range of dilution rates, rotifers and algae coexisted, and population fluctuations of algae clearly increased as dilution rates decreased. The CV of herbivore densities was highest at the end of the experiment, when the dilution rate was low. On day 80, herbivorous rotifers had become undetectable in all three chemostats with permanently defended algae (where rotifer densities had already been low) and in two out of three chemostats where rotifers had been feeding on algae with inducible defenses (that represented more edible food). We interpret our results in relation to the paradox of enrichment.
尼科尔森-贝利模型中诱导防御的动态效应。
影响因子：
1.4
作者：
Kopp,Michael;Gabriel,Wilfried
通讯作者：
Gabriel,Wilfried