Centre for Nutrition Modelling, Department of Animal Biosciences, University of Guelph, Guelph, Ontario, Canada.
Department of Biology, Wilfrid Laurier University, Waterloo, Ontario, Canada.
PLoS One. 2022 Feb 17;17(2):e0252911. doi: 10.1371/journal.pone.0252911. eCollection 2022.
Aphids can have a significant impact on the growth and commercial yield of spruce plantations. Here we develop a mechanistic deterministic mathematical model for the dynamics of the green spruce aphid (Elatobium abietum Walker) growing on Sitka spruce (Picea sitchensis (Bong.) Carr.). These grow in a northern British climate in managed plantations, with planting, thinning and a 60-year rotation. Aphid infestation rarely kills the tree but can reduce growth by up to 55%. We used the Edinburgh Forest Model (efm) to simulate spruce tree growth. The aphid sub-model is described in detail in an appendix. The only environmental variable which impacts immediately on aphid dynamics is air temperature which varies diurnally and seasonally. The efm variables that are directly significant for the aphid are leaf area and phloem nitrogen and carbon. Aphid population predictions include dying out, annual, biennual and other complex patterns, including chaos. Predicted impacts on plantation yield of managed forests can be large and variable, as has been observed; they are also much affected by temperature, CO2 concentration and other climate variables. However, in this system, increased CO2 concentration appears to ameliorate the severity of the effects of increasing temperatures coupled to worsening aphid infestations on plantation yield.
蚜虫会对云杉种植园的生长和商业产量产生重大影响。在这里，我们为生长在西特卡云杉（Picea sitchensis（Bong.）Carr.）上的绿色云杉蚜虫（Elatobium abietum Walker）的动态开发了一个机械确定性数学模型。这些蚜虫在英国北部气候的管理种植园中生长，种植、间伐和 60 年轮作。蚜虫的侵袭很少会杀死树木，但会使生长减少多达 55%。我们使用爱丁堡森林模型（efm）来模拟云杉树的生长。蚜虫子模型在附录中进行了详细描述。唯一直接影响蚜虫动态的环境变量是空气温度，它随昼夜和季节而变化。对蚜虫直接重要的 efm 变量是叶面积和韧皮部氮和碳。蚜虫种群预测包括灭绝、一年生、二年生和其他复杂模式，包括混沌。对管理森林种植园产量的预测影响可能很大且多变，正如已经观察到的那样；它们也受到温度、CO2 浓度和其他气候变量的很大影响。然而，在这个系统中，增加的 CO2 浓度似乎减轻了与恶化的蚜虫侵袭相关的温度升高对种植园产量的影响的严重程度。
