Response of arboreal Collembola communities to the conversion of lowland rainforest into rubber and oil palm plantations

Abstract

Background In the last decades, Southeast Asia has experienced massive conversion of rainforest into rubber and oil palm monoculture plantations. The effects of this land-use change on canopy arthropods are still largely unknown. Arboreal Collembola are among the most abundant canopy arthropods in tropical forests, potentially forming a major component of the canopy food web by contributing to the decomposition of arboreal litter and being an important prey for canopy arthropod predators. We investigated abundance, richness, and community composition of, as well as the influence of a series of environmental factors on, canopy Collembola communities in four land-use systems in Jambi Province, Sumatra, Indonesia: (1) lowland rainforest, (2) jungle rubber (rubber agroforest), and monoculture plantations of (3) rubber and (4) oil palm. Results Using canopy fogging in 32 research plots in both the dry and rainy seasons in 2013, we collected 77,104 specimens belonging to 68 (morpho) species. Generally, Collembola communities were dominated by few species including two species of the genus Salina (Paronellidae; 34% of total individuals) and two species of Lepidocyrtinae (Entomobryidae; 20%). The abundance of Collembola in lowland rainforest (53.4 ± 30.7 ind. m−2) was more than five times higher than in rubber plantations, and more than ten times higher than in oil palm plantations; abundances in jungle rubber were intermediate. Collembola species richness was highest in rainforest (18.06 ± 3.60 species) and jungle rubber (16.88 ± 2.33 species), more than twice that in rubber or oil palm. Collembola community composition was similar in rainforest and jungle rubber, but different from monoculture plantations which had similar Collembola community composition to each other. The environmental factors governing community composition differed between the land-use systems and varied between seasons. Conclusions Overall, this is the first in-depth report on the structure of arboreal Collembola communities in lowland rainforest and agricultural replacement systems in Southeast Asia. The results highlight the potentially major consequences of land-use change for the functioning of arboreal arthropod food webs.

Rainforest transformation reallocates energy from green to brown food webs

“…Density of canopy arthropods per square metre was calculated by dividing the total abundance of collected arthropods by the number of traps used. Detailed biodiversity declines over the investigated land-use change gradient are published for arboreal communities of ants 67 , beetles 68 , springtails 69 , spiders 33 and parasitoid wasps 66 .…”

Global fine-resolution data on springtail abundance and community structure

“…With literally worldwide distribution, springtails account for ~32% of the global terrestrial arthropod abundance 10 and have global biomass of ~27.5 Megatonn carbon 5 . They are especially numerous in cold regions, but are also ubiquitous in tropical soils 5 , and even tropical canopies 11 . Springtails are central components of the belowground system, affecting litter decomposition, microbial activity, abundance and dispersal, and plant growth, and serving as food for numerous invertebrate predators 12 .…”

“…5 ). Pitfall traps were the second most represented method (7.2%), and we included a single dataset collected using canopy fogging 11 . Most of the samples represented ‘soil’ (79.9% or 35,953 samples) and ‘litter’ microhabitats (54.8% or 24,676 samples).…”

Arthropod traits as proxies for abundance trends in the Azorean Islands

“…For instance, 21 out of the 26 endemic spider species studied here are web-weavers (Cardoso et al 2011b), which are known for their need of tridimensional vegetation structure and habitat complexity to build their webs, which in turn make them vulnerable to human activities that subside environmental complexity (Dimitrov et al 2017, Macías-Hernández et al 2020, Oyarzabal and Guimarães 2021. Therefore, the non-occupancy of only natural habitats by endemic spiders goes beyond competition and exclusion by exotic spiders, lying also in the constant threat due to habitat structure changes and other human related drivers of change, either in islands or in continental ecosystems (Hemm and Höfer 2012, Rocha-Ortega et al 2019, Gaona et al 2021, Mawan et al 2022.…”