The functional form of specialised predation affects whether Janzen–Connell effects can prevent competitive exclusion,Ecology Letters

当前位置： X-MOL 学术 › Ecol. Lett. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

The functional form of specialised predation affects whether Janzen–Connell effects can prevent competitive exclusion
Ecology Letters ( IF 7.6 ) Pub Date : 2022-04-26 , DOI: 10.1111/ele.14014
Daniel J B Smith ₁

Affiliation

Janzen–Connell effects (JCEs), specialised predation of seeds and seedlings near conspecific trees, are hypothesised to maintain species richness. While previous studies show JCEs can maintain high richness relative to neutral communities, recent theoretical work indicates JCEs may weakly inhibit competitive exclusion when species exhibit interspecific fitness variation. However, recent models make somewhat restrictive assumptions about the functional form of specialised predation—that JCEs occur at a fixed rate when offspring are within a fixed distance of a conspecific tree. Using a theoretical model, I show that the functional form of JCEs largely impacts their ability to maintain coexistence. If predation pressure increases additively with adult tree density and decays exponentially with distance, JCEs maintain considerably higher species richness than predicted by recent models. Loosely parameterising the model with data from a Panamanian tree community, I elucidate the conditions under which JCEs are capable of maintaining high species richness.

中文翻译：

专门捕食的功能形式影响 Janzen-Connell 效应是否可以防止竞争排斥

Janzen-Connell 效应 (JCE) 是对同种树附近的种子和幼苗的专门捕食，被假设为保持物种丰富度。虽然先前的研究表明 JCE 可以保持相对于中性群落的高丰富度，但最近的理论工作表明，当物种表现出种间适应度变化时，JCE 可能会弱抑制竞争排斥。然而，最近的模型对专门捕食的功能形式做出了一些限制性的假设——当后代在同种树的固定距离内时，JCE 以固定的速率发生。使用理论模型，我表明 JCE 的功能形式在很大程度上影响了它们维持共存的能力。如果捕食压力随着成年树密度的增加而增加并随着距离呈指数衰减，JCE 保持的物种丰富度比最近的模型预测的要高得多。使用来自巴拿马树木群落的数据对模型进行松散参数化，我阐明了 JCE 能够保持高物种丰富度的条件。

更新日期：2022-04-26

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南11