Converting natural vegetation to farmland alters functional structure of ground-dwelling beetles and spiders in a desert oasis

• Published in: Journal of insect conservation Vol. 18; no. 1; pp. 57 - 67
• Main Authors: Li, Feng-Rui, Liu, Ji-Liang, Sun, Te-Sheng, Jin, Bo-Wen, Chen, Li-Juan
• Format: Journal Article
• Language: English
• Published: Cham Springer-Verlag 01.02.2014; Springer International Publishing; Springer; Springer Nature B.V
• Subjects: Agricultural land; Agronomy. Soil science and plant productions; Animal Ecology; Animal populations; Animal, plant and microbial ecology; Applied ecology; Araneae; Arid zones; Biodiversity; Biological and medical sciences; Biomedical and Life Sciences; Coleoptera; Conservation Biology/Ecology; Conservation, protection and management of environment and wildlife; crop production; Deserts; Ecosystem services; Entomology; Fundamental and applied biological sciences. Psychology; General agroecology; General agroecology. Agricultural and farming systems. Agricultural development. Rural area planning. Landscaping; General agronomy. Plant production; Generalities. Agricultural and farming systems. Agricultural development; Herbivores; human population; Human populations; insect pests; Insects; Irrigated farming; Land use; land use change; Landscape ecology; Life Sciences; natural enemies; Natural vegetation; oases; Original Paper; Parks, reserves, wildlife conservation. Endangered species: population survey and restocking; Pest control; Pests; Pitfall traps; Pollination; Pollinators; Predators; Spiders; Steppes; China, People's Rep; Detritivorous arthropods; Biological pest control; Ecosystem services; Predatory arthropods; Agricultural expansion; Land-use change; Coleoptera; Insecta; Biological control; Farmland; Soil fauna; Natural environment; Pest management; Agriculture; Detritivorous; Animal conservation; Expansion; Araneida; Oasis; Agroecosystem; Arachnida; Arthropoda; Environment impact; Vegetation; Ecosystem functioning; Desert; Predator; Invertebrata; Environmental monitoring
• ISSN: 1366-638X; 1572-9753
• DOI: 10.1007/s10841-014-9614-z

A vast area of native shrub-dominated steppe at the margins of desert oases in arid regions of China had been reclaimed as farmland in the last century for grain production to feed growing human populations. This study evaluated the consequences of this land-use change on the activity density, taxa richness and composition of functional groups (herbivores, predators and detritivores) of ground-dwelling beetles and spiders, which include some important ecological groups of natural enemies of insect pests (e.g. predatory spiders and beetles), pollinators and decomposers (e.g. detritivorous beetles). Ground-dwelling beetles and spiders were collected using pitfall traps in native steppe habitats and adjacent irrigated farmland of different ages (cultivated either for 27 or at least for 90 years). It was found the conversion of native steppe to farmland, regardless of farmland age, led to a significant increase in activity density of predators, with a greater increase in 90-year-old farmland than in 27-year-old farmland, but did not affect their taxa richness. However, native steppe conversion to farmland, regardless of farmland age, led to significant declines in activity density and taxa richness of both detritivores and herbivores, with a much greater decrease of activity or richness in detritivores than in herbivores in both farmland types. We also observed taxa-specific responses to the land conversion within functional groups. The functional composition of the beetle and spider community shifted from a community dominated by detritivores in the native steppe sites to one dominated by predators in the irrigated farmland sites. Our results suggest that the different functional groups of ground-dwelling beetles and spiders responded in a different way to the land conversion. The remarkable increase in predators and the dramatic decline in detritivores by converting natural vegetation to agricultural land are expected to strongly affect the desert ecosystem services such as biological pest control, pollination and decomposition.