德国拜罗伊特大学Hulsmann, Lisa团队最新的研究揭示了稳定森林群落密度依赖的纬向模式。这一研究成果发表在2024年2月28日出版的国际学术期刊《自然》上。

该研究团队提出了一个纬度CNDD模式的综合评估，使用动态死亡率数据，以估计23个站点的物种特异性CNDD。在物种间平均，研究人员发现，稳定的CNDD在除一个站点外的所有站点都存在，但平均稳定的CNDD在热带地区并不强。然而，在热带树木群落中，稀有和中等丰度树种的稳定CNDD强于普通树种。

这种模式在温带森林中不存在，表明CNDD对热带森林物种丰度的影响比对温带森林更强烈。研究发现，CNDD的种间变异很高，但在纬度上差异不显著，这可能会削弱其对物种多样性的稳定作用。尽管这些模式对纬度多样性梯度的影响难以评估，但研究人员推测，更有效的种群丰度调节可以转化为热带树木群落的更大稳定性，从而有助于热带森林的高局部多样性。

据悉，大量研究表明，周围被相同物种所包围的植物的性能会降低，这种现象被称为同种负密度依赖(CNDD)。一个长期存在的生态学假说认为，CNDD在热带森林比在温带森林更明显，这增加了群落稳定、物种共存和当地树种的多样性。先前的分析支持CNDD的纬度梯度受到与使用静态数据相关的方法限制。

附：英文原文

Title: Latitudinal patterns in stabilizing density dependence of forest communities

Author: Hlsmann, Lisa, Chisholm, Ryan A., Comita, Liza, Visser, Marco D., de Souza Leite, Melina, Aguilar, Salomon, Anderson-Teixeira, Kristina J., Bourg, Norman A., Brockelman, Warren Y., Bunyavejchewin, Sarayudh, Castao, Nicolas, Chang-Yang, Chia-Hao, Chuyong, George B., Clay, Keith, Davies, Stuart J., Duque, Alvaro, Ediriweera, Sisira, Ewango, Corneille, Gilbert, Gregory S., Holk, Jan, Howe, Robert W., Hubbell, Stephen P., Itoh, Akira, Johnson, Daniel J., Kenfack, David, Krl, Kamil, Larson, Andrew J., Lutz, James A., Makana, Jean-Remy, Malhi, Yadvinder, McMahon, Sean M., McShea, William J., Mohamad, Mohizah, Nasardin, Musalmah, Nathalang, Anuttara, Norden, Natalia, Oliveira, Alexandre A., Parmigiani, Renan, Perez, Rolando, Phillips, Richard P., Pongpattananurak, Nantachai, Sun, I-Fang, Swanson, Mark E., Tan, Sylvester, Thomas, Duncan, Thompson, Jill, Uriarte, Maria, Wolf, Amy T., Yao, Tze Leong, Zimmerman, Jess K., Zuleta, Daniel, Hartig, Florian

Issue&Volume: 2024-02-28

Abstract: Numerous studies have shown reduced performance in plants that are surrounded by neighbours of the same species, a phenomenon known as conspecific negative density dependence (CNDD). A long-held ecological hypothesis posits that CNDD is more pronounced in tropical than in temperate forests, which increases community stabilization, species coexistence and the diversity of local tree species. Previous analyses supporting such a latitudinal gradient in CNDD have suffered from methodological limitations related to the use of static data. Here we present a comprehensive assessment of latitudinal CNDD patterns using dynamic mortality data to estimate species-site-specific CNDD across 23 sites. Averaged across species, we found that stabilizing CNDD was present at all except one site, but that average stabilizing CNDD was not stronger toward the tropics. However, in tropical tree communities, rare and intermediate abundant species experienced stronger stabilizing CNDD than did common species. This pattern was absent in temperate forests, which suggests that CNDD influences species abundances more strongly in tropical forests than it does in temperate ones. We also found that interspecific variation in CNDD, which might attenuate its stabilizing effect on species diversity, was high but not significantly different across latitudes. Although the consequences of these patterns for latitudinal diversity gradients are difficult to evaluate, we speculate that a more effective regulation of population abundances could translate into greater stabilization of tropical tree communities and thus contribute to the high local diversity of tropical forests.

DOI: 10.1038/s41586-024-07118-4

Source: https://www.nature.com/articles/s41586-024-07118-4