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The Huangshandong deposit, located in the Central Asian Orogenic Belt (CAOB), is the largest Ni–Cu sulfide deposit in the eastern Tianshan and Beishan regions of China. The deposit is hosted in a postorogenic intrusion that comprises diorite, gabbrodiorite, bojite, olivine gabbro, gabbronorite, troctolite, and lherzolite. Here, we report the Permian zircon U–Pb crystallization ages of 278.5 ± 2.1 Ma, 278.1 ± 1.9 Ma, and 279.6 ± 1.9 Ma for the olivine gabbro, bojite, and gabbrodiorite, respectively, as well as geological, petrological, and geochemical data for the various lithofacies of the deposit. As a result of the edge cooling effect, the intrusion cooled rapidly from the outside inwards as follows: crystallizing diorite → gabbrodiorite → gabbro → lherzolite → gabbronorite. In addition, further tectonic activity resulted in the injection of a more primitive magma in place, which crystallized the lherzolite in the bottom and middle transitional zones of the intrusion. The crystallization sequence of the intrusion is generally as follows: olivine → orthopyroxene + labradorite → clinopyroxene + labradorite → amphibole + andesine. At the beginning of mineral crystallization, the metalliferous magma was segregated due to sulfide immiscibility and separated by gravity. With gabbronorite crystallization, the immiscible liquid sank to the base of the magma chamber and crystallized as Cu‐ and Ni‐rich sulfides. Tholeiitic and calc‐alkaline rocks are characterized by relative enrichment in large‐ion lithophile elements and depletion in high‐field‐strength elements, and values of Th/Ta (2.25–5.94), (Nb/La)N (1.88–4.39), and Th/Nb (0.29–0.82) indicate that the mantle source was composed of a dehydrated subducted plate or mantle wedge. In addition, values of Nb/U (2.64–10.68) and Ce/Pb (1.33–3.53) suggest that the magma was contaminated by the continental crust during its ascent along pre‐existing structures in the Carboniferous strata. [ABSTRACT FROM AUTHOR]

Clear species boundaries are crucial for plans and actions on biodiversity conservation. However, morphological similarities among allied species can result in taxonomic difficulties, thus impeding conservation efforts. In China, Cinnamomum japonicumSiebold is a well‐known endangered plant, yet suffers from longstanding taxonomic issues. Here, we explicitly evaluate whether C. japonicum, C. chenii, and C. chekiangense are the same phylogenetic species on the basis of a multi‐individual sampling strategy. We identified three sets of low‐copy orthologous genes from 19 Lauraceae taxa for phylogenetic inferences. Both the concatenation and coalescent‐based phylogenies supported that C. chenii individuals were embedded in the C. japonicum clade, indicating these two taxa are conspecific. Meanwhile, C. chekiangense accessions formed a monophyly which was not sister to C. japonicum. This result, together with the morphological differences that the leaves of C. japonicum are glabrous with a faveolate pattern of venation while those of C. chekiangense have trichomes and inevident lateral veins, led us to consider both as two distinct species. Based on 17 728 neutral single nucleotide polymorphisms (SNPs), the ADMIXTURE analysis suggested that the Chinese C. japonicum populations in Zhoushan Archipelago (=C. chenii) were genetically differentiated from the Japanese and Korean ones. Furthermore, ecological niche modeling predicted that the present distribution area of Chinese C. japonicum is likely to be unsuitable under global warming scenarios. Together with its limited distribution and genetic uniqueness, we recommend that Chinese C. japonicum deserves conservation priorities. [ABSTRACT FROM AUTHOR]

Summary: Global warming is advancing the timing of spring leaf‐out in temperate and boreal plants, affecting biological interactions and global biogeochemical cycles. However, spatial variation in spring phenological responsiveness to climate change within species remains poorly understood.Here, we investigated variation in the responsiveness of spring phenology to temperature (RSP; days to leaf‐out at a given temperature) in 2754 Ginkgo biloba twigs of trees distributed across subtropical and temperate regions in China from 24°N to 44°N.We found a nonlinear effect of mean annual temperature on spatial variation in RSP, with the highest response rate at c. 12°C and lower response rates at warmer or colder temperatures due to declines in winter chilling accumulation. We then predicted the spatial maxima in RSP under current and future climate scenarios, and found that trees are currently most responsive in central China, which corresponds to the species' main distribution area. Under a high‐emission scenario, we predict a 4‐degree latitude shift in the responsiveness maximum toward higher latitudes over the rest of the century.The identification of the nonlinear responsiveness of spring phenology to climate gradients and the spatial shifts in phenological responsiveness expected under climate change represent new mechanistic insights that can inform models of spring phenology and ecosystem functioning. [ABSTRACT FROM AUTHOR]

Accurate species delimitation is the key to precise estimation of species diversity and is fundamental to most branches of biology. Unclear species boundaries within species complexes could lead to the underestimation of species diversity. However, species delimitation of species complexes remains challenging due to the continuum of phenotypic variations. To robustly examine species boundaries within a species complex, integrative approaches in phylogeny, ecology, and morphology were applied to the Stewartia sinensis complex (Theaceae) endemic to China. Multispecies coalescent‐based species delimitation using 572 nuclear ortholog sequences (anchored enrichment) supported reciprocal phylogenetic monophyly of the northern lineage (NL) and southern lineage (SL), which were not sister clades. Niche equivalency and similarity tests demonstrated significant climatic niche differentiation between NL and SL with observed Warren et al.'s I = 0.0073 and Schoener's D = 0.0021. Species distribution modeling also separated their potential distribution. Morphometric analyses suggested significant interlineage differentiation of multiple traits including the ratio of length and width, leaf width, and pedicel length, although overall similarity did not differ. Based on the integrative species concept, two distinct species were proposed with legitimate names of Stewartia gemmata for SL and S. sinensis for NL. Our empirical study of the S. sinensis complex highlights the importance of applying multiple species criteria, in particular the underappreciated niche differentiation, to species delimitation in species complexes pervasive in plants. [ABSTRACT FROM AUTHOR]

This account presents information on all aspects of the biology of Ginkgo biloba L. (Ginkgo, Maidenhair tree) that are relevant to understanding its ecological characteristics. The main topics are presented within the standard framework of the International Biological Flora: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, reproductive and seed characters, herbivores and disease, history, conservation and global heterogeneity.Globally, Ginkgo survives a wide range of mean annual temperature (−3.3 to 23.3°C) and annual precipitation (34–3925 mm) conditions, according to a meta‐analysis. It prefers a warm, humid, open‐canopy and a well‐drained environment. The species shows strong tolerance to drought, freezing, fire, air pollution, heavy metals and low‐level salt, whereas it is intolerant to long‐time shade and waterlogging. Six Ginkgo trees even survived the atom bomb in Hiroshima, Japan, during World War II.Ginkgo is susceptible to few diseases. Those occurring in nursery seedlings and juvenile trees involve stem rot and leaf blight. The former is caused by Macrophomina phaseoli, which could lead to a mortality rate of 5%–12% (up to 31.8%) for seedlings. This disease can be mitigated by a 4‐h shading treatment and applying organic fertilisers. The pathogens inducing leaf blight include Alternaria alternata, Colletotrichum gloeosporioides and Pestalotia ginkgo, which may infect 100% juvenile trees in some regions. The application of 45% carbendazim or 50% Tuzet can effectively prevent leaf blight.Ginkgo biloba is one of the world's most distinctive trees with an important position in plant evolution and human society. It is a tall deciduous dioecious tree native to China. Refugial populations were identified in three glacial refugia located in eastern, southern and south‐western China, respectively, with a patchy distribution pattern and a small population size. It typically grows along flood‐disturbed streamsides in warm‐temperate deciduous (and evergreen mixed) broadleaved forests. Ginkgo may have been introduced repeatedly out of China since the sixth century. It has been planted as a landscape tree world‐wide, except in Antarctica. Ginkgo is also of great value for edible nuts, herbal medicine, religion and art. It is a natural and cultural symbol of China. [ABSTRACT FROM AUTHOR]

The Derbur lead–zinc deposit is located in the Derbugan metallogenic belt in the north‐western portion of the Mesozoic Hailaer‐Genhe volcanic basin in the northern Great Xing'an Range. This deposit occurs in the Middle Jurassic intermediate–mafic volcanic rocks of the Tamulangou Formation and is spatially and temporally associated with acidic pyroclastic rocks. The host rocks are bedded trachyandesite and rhyolitic lithic‐crystal tuffs, and basaltic‐andesitic aplite veins are associated with the ore body. Because the deposit is a hypabyssal low‐temperature hydrothermal Pb–Zn deposit associated with volcanism, to determine the precise petrogenesis of the volcanic rocks, this study analysed the zircon U–Pb ages of the trachyandesite and rhyolitic lithic‐crystal tuffs, the Sr–Nd–Pb isotopic geochemistry of the trachyandesite and basaltic‐andesitic aplite, and the whole‐rock geochemistry of all three rock types. The results showed that the trachyandesite and basaltic‐andesitic aplite belong to the shoshonitic series and have similar whole‐rock and isotopic geochemical characteristics, including enrichments in large‐ion lithophile elements and light rare earth elements and depletions in high‐field‐strength elements. They also have low initial 87Sr/86Sr values of 0.705007–0.705240 and εNd(t) values of +0.6 to +1.7, with model ages (TDM) of 699–883 Ma. The ratios of 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb vary from 18.438 to 18.476, 15.570 to 15.577, and 38.254 to 38.320, respectively, with μ values of 9.40–9.41. In contrast, the rhyolitic lithic‐crystal tuffs are characterized by high SiO2 contents (73.44–79.48 wt.%); low Al2O3 (11.36–12.53 wt.%), TiO2 (0.14–0.18 wt.%), and K2O + Na2O (3.48–3.89 wt.%, Na2O ≤ K2O) contents; and low Mg# values (0.17–0.41), indicating that they belong to the calc–alkaline series. Additionally, they have relatively low REE contents and strong Sr depletions. LA‐ICP‐MS zircon U–Pb dating of the trachyandesite and rhyolitic lithic‐crystal tuffs indicates that their ages are 167.0 ± 2.0 Ma and 164.8 ± 1.6 Ma, respectively. We conclude that the trachyandesite and the basaltic‐andesitic aplite were derived from the partial melting of lower crustal material assimilated by a depleted lithospheric mantle that was subsequently metasomatized by subducted slab‐derived fluids. The rhyolitic lithic‐crystal tuffs likely originated from the partial melting of accreted lower crust. In summary, because the acidic volcanism was accompanied by increasingly felsic volcanism, bimodal volcanic rocks were produced. Among volcanogenic deposits, bimodal volcanic rocks are the most favourable ore‐hosting rocks, and ore‐forming materials were contributed by the magmatic system. These processes created conditions conducive to the formation of large‐scale Ag, Pb, and Zn mineralization in this area. [ABSTRACT FROM AUTHOR]

Aim: The present study aimed to investigate and identify the association between the intake of allium vegetables and colorectal cancer (CRC) in population. Methods: A hospital‐based matched case‐control study was conducted between June 2009 and November 2011 in three hospitals. Eight hundred thirty three consecutively recruited cases of CRC were frequency matched to 833 controls by age (within 2.5 years of difference), sex, and residence area (rural/urban). Demographic and dietary information were collected via face‐to‐face interviews using a validated food frequency questionnaire. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated by using unconditional logistic regression. Results: A decreased CRC risk was observed for the consumption of total (aORs of high total allium intake compared with low total allium intake = 0.21, 95% CI = 0.14–0.30, P trend <0.001) and several individual allium vegetables including garlic, garlic stalks, leek, onion, and spring onion (P trend <0.05). By further sex‐stratified analysis, allium vegetable intake was demonstrated to be inversely associated with the risk of CRC in both men and women. However, the association of garlic intake with cancer risk was not significant among those with distal colon cancer (aOR = 0.53, 95% CI = 0.27–1.05, P trend = 0.248). Conclusion: In this analysis in a Northeast Chinese population, both men and women that the consumption of allium vegetables is associated with a reduced risk of CRC, regardless of colonic tumor subsite, with the exception of garlic intake in distal colon cancer. [ABSTRACT FROM AUTHOR]

As a medicinal herb, Atractylodes macrocephala Koidz. experienced centuries of cultivation in China, and germplasm resources of all cultivated populations have degraded over time as a consequence of domestication processes. This study used chloroplast DNA and microsatellites to clarify not only the effects of domestication on population genetics, but also determine the geographic origins of landraces. The results revealed that cultivated populations (except the "Pingzhu" landrace) showed higher genetic diversity than their wild counterparts and low levels of genetic differentiation occurred between cultivated and wild groups. Furthermore, STRUCTURE and UPGMA analyses grouped all wild populations into three genotypic clusters, two of which (in Shaanxi and Hunan Province) shared the same gene pool with cultivated A. macrocephala, suggesting that wild populations in Central China have been involved in the origin of cultivated A. macrocephala. Moreover, the wild population from Qimen, Anhui Province and the cultivated "Pingzhu" landrace harbor unique gene pools and rare alleles that could be useful in future breeding efforts. This large‐scale analysis of population genetics on a medicinal herb that has a centuries‐long history of human‐mediated selection will facilitate utilization and conservation of the valuable genetic resources of medicinal species. [ABSTRACT FROM AUTHOR]