Does plant diversity benefit agroecosystems? A synthetic review
Does plant diversity benefit agroecosystems? A synthetic review
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DOI：
10.1890/09-2026.1
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发表时间：
2011-01-01
影响因子：
5
通讯作者：
Reyes Trujillo, Aldemar
中科院分区：
文献类型：
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作者：
Letourneau, Deborah K.;Armbrecht, Inge;Reyes Trujillo, Aldemar
植物多样性如何促进草食动物抑制通过运动模式，主机协会和捕食的预测理论，承诺农药密集型单一作物生产的潜在替代品。我们对过去10年发表的45篇文章中的552个实验进行了荟萃分析，以测试植物多样化方案是否减少了食草动物和/或增加了食草动物的天敌，正如联合抗性假说，天敌假说以及农业中的吸引力和排斥力模型应用所预测的那样。我们发现广泛支持这些模式与间作计划，包括开花植物，并使用植物，击退食草动物或吸引他们远离作物。总体而言，草食动物的抑制，敌人的增强，作物损害抑制效果显着更强的多样化作物比作物没有或更少的相关植物物种。然而，一个相对较小的，但显着的负面影响，作物产量的平均效应大小表明，害虫抑制多样化计划干扰生产，部分原因是减少密度的主要作物，取代它与间作或非作物植物。这是第一次使用元分析来评估多样化计划的影响，这是一个可能比统计显著的积极和消极结果（计票）更强大的工具，与以前的审查相比，对所有测量参数的总体影响更大。我们对最近一篇综述中使用的相同文章的分析有助于比较投票计数和荟萃分析，并表明荟萃分析的显著结果并不能很好地解释为符合其更严格标准的文章减少。相反，与结局计数相比，效应量很少是中性的（等于零），可以计算混合结局的平均效应量值。元分析避免了计票的统计特性问题，从而提供了更精确的假设检验。对以前研究的荟萃分析得出的明确和令人鼓舞的结果应该激励生态学家进行更多的机械实验，以提高设计有效作物多样化方案的可能性，从而改善害虫管理和提高作物产量。
Predictive theory on how plant diversity promotes herbivore suppression through movement patterns, host associations, and predation promises a potential alternative to pesticide-intensive monoculture crop production. We used meta-analysis on 552 experiments in 45 articles published over the last 10 years to test if plant diversification schemes reduce herbivores and/or increase the natural enemies of herbivores as predicted by associational resistance hypotheses, the enemies hypothesis, and attraction and repellency model applications in agriculture. We found extensive support for these models with intercropping schemes, inclusion of flowering plants, and use of plants that repel herbivores or attract them away from the crop. Overall, herbivore suppression, enemy enhancement, and crop damage suppression effects were significantly stronger on diversified crops than on crops with none or fewer associated plant species. However, a relatively small, but significantly negative, mean effect size for crop yield indicated that pest-suppressive diversification schemes interfered with production, in part because of reducing densities of the main crop by replacing it with intercrops or non-crop plants. This first use of meta-analysis to evaluate the effects of diversification schemes, a potentially more powerful tool than tallies of significant positive and negative outcomes (vote-counting), revealed stronger overall effects on all parameters measured compared to previous reviews. Our analysis of the same articles used in a recent review facilitates comparisons of vote-counting and meta-analysis, and shows that pronounced results of the meta-analysis are not well explained by a reduction in articles that met its stricter criteria. Rather, compared to outcome counts, effect sizes were rarely neutral (equal to zero), and a mean effect size value for mixed outcomes could be calculated. Problematic statistical properties of vote-counting were avoided with meta-analysis, thus providing a more precise test of the hypotheses. The unambiguous and encouraging results from this meta-analysis of previous research should motivate ecologists to conduct more mechanistic experiments to improve the odds of designing effective crop diversification schemes for improved pest regulation and enhanced crop yield.