Geometrid moth assemblages reflect high conservation value of naturally regenerated secondary forests in temperate China

Abstract

The widespread destruction of mature forests in China has led to massive ecological degradation, counteracted in recent decades by substantial efforts to promote forest plantations and protect secondary forest ecosystems. The value of the resulting forests for biodiversity conservation is widely unknown, particularly in relation to highly diverse invertebrate taxa that fulfil important ecosystem services. We aimed to address this knowledge gap, establishing the conservation value of secondary forests on Dongling Mountain, North China based on the diversity of geometrid moths – a species-rich family of nocturnal pollinators that also influences plant assemblages through caterpillar herbivory. Results showed that secondary forests harboured geometrid moth assemblages similar in species richness and phylogenetic diversity, but with a species composition distinctly different to assemblages in one of China’s last remaining mature temperate forests in the Changbaishan Nature Reserve. Species overlap between these sites was about 30%, and species did not form separate phylogenetic clusters according to site. Species assemblages at Dongling Mountain were strongly differentiated according to forest type; a pattern not found at Changbaishan. Our results indicate that protected naturally regenerated secondary forests in northern China provide suitable habitats for species-rich and genetically diverse geometrid moth assemblages, highlighting the potential importance of these forests for conservation and ecosystem function provision across the wider landscape

Large‐scale α‐diversity patterns in plants and ground beetles (Coleoptera: Carabidae) indicate a high biodiversity conservation value of China's restored temperate forest landscapes

“…On the contrary, we found the lowest dissimilarity in mature forests. Such results are in line with previous studies of both geometrid moths and carabid beetles in one of our study areas, at Donglingshan, where species dissimilarity was higher than in the mature forest at Changbaishan (Zou, Sang, Wang, et al, ; Zou et al, ). The relatively high dissimilarity in beetle assemblages within secondary and plantation forests suggests that they are not strongly dominated by generalists.…”

“…The difference could be related to plantation forests in Europe harbouring a much lower tree species richness than plantation forests in our study region. In fact, our results also correspond with patterns previously reported for geometrid moths in secondary and mature forests from two of our study areas, Changbaishan and Donglingshan, where recently established forests were shown to harbour similar levels of α‐diversity to mature forests (Zou et al, ). In addition, our results are in line with a recent study from south‐central China by Hua et al (), who reported general positive impacts of species‐rich mixed forests on regional biodiversity.…”

“…As the sample size differed among sampling plots, we selected sample size‐independent diversity indices as indicators of carabid's α‐diversity: rarefied species richness (standardized for 30 individuals) and Fisher's alpha. These two indices have been commonly used in studies of mobile insects that allow us to compare plots with different sample completeness and sample size (Axmacher et al, ; Beck & Schwanghart, ; Brehm, Süssenbach, & Fiedler, ; García‐López, Micó, & Galante, ; Zou et al, ). In order to have a robust estimation of the α‐diversity, plots with <30 carabid specimens (27 plots) were excluded from this analysis.…”

“…The implications of China's reforestation and afforestation initiatives for the conservation of invertebrates, in terms of α‐diversity and assemblage composition, therefore, require urgent attention. There are already a small number of case studies assessing the insect biodiversity conservation value of individual forest areas (Zou, Sang, Wang, et al, ; Zou, Sang, Warren‐Thomas, & Axmacher, ). Nonetheless, the small scale and lack of replicates in these studies mean that their results cannot be extrapolated across wider geographic areas.…”

Mercury concentrations and pools in four adjacent coniferous and deciduous upland forests in Beijing, China

“…Due to cool and dry climate, the litter decomposes lowly, which results in deep litter and organic layers [ Yu et al , ]. In the area, oak ( Quercus liaotungensis Mayr) forest is the originally main forest type, but some areas are partly reforested with coniferous plantations of evergreen Chinese pine ( Chinese pine tabulaeformis ), larch ( Larix principis‐rupprechtii ), and mixed deciduous forest ( Betula platyphylla Suk, Carya cathayensis Sarg, Betula dahurica Pall, and Acer mono ) [ Zou et al , ]. Therefore, these four forest types were selected for the study: Chinese pine plantation, larch plantation, oak forest, and mixed deciduous broad‐leaved forest.…”