Thinning‐induced canopy opening exerted a specific effect on soil nematode community

Abstract

Changes in microclimate, soil physicochemical properties, understory vegetation cover, diversity, and composition as well as soil microbial community resulting from silvicultural practices are expected to alter soil food webs. Here, we investigated whether and how contrasting‐sized canopy openings affect soil nematode community within a 30 year‐aged spruce plantation. The results indicated that the responses of soil nematodes to canopy opening size were dependant on their feeding habit. The abundance of total nematodes and that of free‐living nematodes was negatively correlated with soil bulk density, whereas the abundance of omnivore–predators was negatively correlated with soil bulk density and shrubs cover, respectively. The ratio of the sum abundance of predators and omnivores to the plant parasites’ abundance, Simpson's dominance index, Pielou's evenness index, and sigma maturity index, maturity index (MI), MI 2‐5, basal index, enrichment index, and structure index was sensitive to alteration in canopy opening size. Multivariate analysis indicated that thinning‐induced gap size resulted in contrasting nematode assemblages. In conclusion, soil nematodes should be integrated as an indicator to monitor soil multifunctionality change due to thinning.

Response of Soil Nematode Community to Phosphorous Amendment in a Subalpine Spruce Plantation

“…Nematodes were extracted from 100 g fresh soil using the minor modified cotton‐wool filter method . Nematodes were collected after 72 h from extraction.…”

“…Soil food web indices include basal index (BI), channel index (CI), enrichment index (EI) and structure index (SI). Additionally, taxa richness (S), Margalef's richness (SR) Shannon‐Wiener index ( H ′), Pielou evenness index ( J ′), and Simpson dominance index (λ) were calculated …”

Nature Restoration Shifts the Abundance and Structure of Soil Nematode Communities in Subtropical China

“…Secondly, soil biota in the higher trophic level require a longer time to adapt to changes in habitats than that in the lower trophic level (Valladares et al, 2012). Another possible explanation may be the distinct linkages among guilds in the soil food webs, because different trophic levels participated in differential interactions, including competition, predation, and mutualistic symbiosis (Yang et al, 2018).…”

Prescribed fire alters nematode communities in an old‐field grassland

“…Nematode data were also used to calculate Maturity Index (MI) (Yang et al, 2018 ), Channel Index (CI), Enrichment Index (EI), and Structure Index (SI) (Ferris et al, 2001 ). Lower and higher values of MI indicate disturbed and stable nematode communities, respectively.…”

“…The diversity and ecological indices were calculated as following. Shannon‐Weaver Index: H ′ = −∑ p i ln p i , (Yang et al, 2018 ); Simpson dominance index, D = ∑ p i 2 , where p i is the proportion of individuals in the i th taxon (Simpson, 1949 ); Maturity index: MI = ∑ v i × f i , where v i is c‐p value of taxon in according to their r or k characteristics, f i is the frequency of taxon i in the plot (Yang et al, 2018 ); Chanel index CI = 100 × [0.8 Fu 2 /(3.2 Ba 1 + 0.8 Fu 2 )] (Ferris et al, 2001 ); Enrichment index: EI = 100 × ∑ k e n e /(∑ k b n b + ∑ k e n e ) (Ferris et al, 2001 ); Structure index: SI = 100 × ∑ k s n s /(∑ k b n b + ∑ k s n s ) (Ferris et al, 2001 ), where n b is the abundance of individuals and k b is the weighting in guilds Ba 1 and Fu 2 , which represent the basal characteristics of soil food web; k s is similar weighting assigned to Ba 3 ‐Ba 5 , Fu 3 ‐Fu 5 , Op 3 ‐Op 5 ; and n s is the abundance of above‐mentioned guilds. Ba x , Fu x , Op x (where x = 1–5) represent c‐p values and feeding groups following Bongers and Bongers ( 1998 ).…”