Pleskalt Andro, Farias Sebastião, Vicedo Toni, Álvarez-Martínez Jose Manuel, Roces-Díaz José Valentín, Meloro Carlo, Pereira Soraia, Cruz Antonio, García Jesús, Gómez Pablo, Lamillar María Ángel, Marsella Elena, Varas Manuel Jesús, Álvarez Elena, Dalerum Fredrik
Department of Biology, University of Zagreb, Zagreb, Croatia.
Department of Statistics and Operational Research, University of Lisbon, Lisbon, Portugal.
R Soc Open Sci. 2025 Aug 6;12(8):250472. doi: 10.1098/rsos.250472. eCollection 2025 Aug.
The distribution of biomass among trophic levels and different types of organisms is a key characteristic of ecosystems. However, such biomass distributions might exhibit large perturbations owing to human activities. We used long-term camera trap data from a temperate forest ecosystem within the Cantabrian range, northern Spain, to quantify the biomass distribution of 10 mammal species ranging in body mass from 300 g to almost 100 kg. The species are representative of three distinct orders and include trophic levels from primary to secondary consumers. The observed biomass distribution was bottom-heavy with a disproportionally low biomass of secondary consumers, in particular large-bodied predators. In addition, the ratio of plant biomass to the biomass of mammalian primary consumers was over 6000 : 1 for total above-ground-plant biomass and over 700 : 1 for plant biomass available for mammal consumption. We suggest that the observed biomass distribution both among mammals and between mammals and plants provide an example of trophic downgrading, and highlight the radical effects human activities might have on the structure of terrestrial ecosystems.
生物量在营养级和不同类型生物之间的分布是生态系统的一个关键特征。然而，由于人类活动，这种生物量分布可能会出现大幅扰动。我们利用来自西班牙北部坎塔布连山脉一个温带森林生态系统的长期相机陷阱数据，对体重从300克到近100千克的10种哺乳动物的生物量分布进行了量化。这些物种代表了三个不同的目，包括从初级消费者到次级消费者的营养级。观察到的生物量分布呈下重上轻，次级消费者，特别是大型食肉动物的生物量比例过低。此外，对于地上植物总生物量，植物生物量与哺乳动物初级消费者生物量的比例超过6000∶1，对于可供哺乳动物食用的植物生物量，这一比例超过700∶1。我们认为，观察到的哺乳动物之间以及哺乳动物与植物之间的生物量分布是营养级降级的一个例子，并突出了人类活动可能对陆地生态系统结构产生的巨大影响。
