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The Science of the Total Environment Feb 2023Soil invertebrates have an essential role in decomposition, nutrient turnover and soil structure formation, all of which are strongly threatened by urbanization.... (Meta-Analysis)
Meta-Analysis Review
Soil invertebrates have an essential role in decomposition, nutrient turnover and soil structure formation, all of which are strongly threatened by urbanization. Sealing, compaction by trampling and pollution destroy and degrade city soils and potentially damage soil-living invertebrates. The existing literature on how urbanization affects soil invertebrates is inconsistent, presenting both negative and positive effects. Therefore, here we aimed to synthesize the effects of urbanization on soil invertebrates considering their taxonomic (Acari, Annelida, Carabidae, Collembola, Gastropoda, Isopoda, Myriapoda, Nematoda) and functional (soil living vs. soil-related; mobility) identities, as well as to examine how the overall effect is modulated by climatic conditions (total annual precipitation, annual mean ambient temperature), urban heat island effect (based on ambient temperature differences between urban and rural areas) and city population. In a systematic review using hierarchical and categorical meta-analyses, we extracted 158 effect sizes from 75 studies on abundance and 125 effect sizes from 84 studies on species richness. Invertebrate abundance showed an increase (r = 0.085), whereas species richness significantly decreased with increasing urbanization (r = -0.168). The reason behind this could be that a few generalist species can adapt well to the urban environment and achieve strongly elevated densities. The species richness of annelids (r = -0.301), springtails (r = -0.579), and snails (r = -0.233) decreased with advancing urbanization, most probably because these animals are sensitive to soil compaction and pollution, both of which are common consequences of urbanization. The temperature did not modify the effects of urbanization, but precipitation modified the effects on abundance (r = -0.457). Abundance increased with advancing urbanization in drier climates, probably because irrigation increased soil moisture, whereas it decreased in wet climates, as urban areas were drier than their surroundings. Making future cities more climate-neutral could better sustain soil biodiversity.
Topics: Animals; Cities; Hot Temperature; Urbanization; Biodiversity; Invertebrates; Soil; Ecosystem
PubMed: 36395843
DOI: 10.1016/j.scitotenv.2022.160145 -
PeerJ 2020A vast polychaete fauna is hidden behind complexes of cryptic and pseudo-cryptic species, which has greatly hindered our understanding of species diversity in several...
A vast polychaete fauna is hidden behind complexes of cryptic and pseudo-cryptic species, which has greatly hindered our understanding of species diversity in several regions worldwide. Among the eunicids, Montagu, 1813 is a typical example, recorded in three oceans and with various species considered its junior synonyms. In South Africa, specimens previously misidentified as are now known as Lewis & Karageorgopoulos, 2008. Of the six Quatrefages, 1865a species recorded from the same region, three have their distributions restricted to South Africa while the others are considered to have worldwide distributions. Here, we evaluated the taxonomic status of the indigenous and investigated the presence of the widespread species Crossland, 1903 and Schmarda, 1861 in South Africa using morphological and molecular data. Our results reveal that is a junior synonym of , a species previously described from South Africa which is herein reinstated as a valid species. Both and are not present in South Africa and their status as being distributed worldwide deserves further investigation. Day, 1934 and the new species described here, n. sp., had been misidentified as and respectively. Thus, the number of species with distributions restricted to South Africa increased from three to five. This study reiterates the importance of implementing an integrated taxonomic framework to unravel local biodiversity.
PubMed: 33150064
DOI: 10.7717/peerj.10076