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One of the main management strategies of China's nature reserve is "zonation", dividing reserves into three zones (core, buffer, and experimental zones) to which different levels of restrictions on anthropogenic activities are applied. While zonation has a positive effect on the conservation of target species, it is unclear whether management zones can be effective in conserving biodiversity. Using bird data collected from five national nature reserves of Guangdong province in China during 2018–2019, we investigated how management zones and reserves are associated with bird diversity and community composition. We considered species richness, the community-weighted mean (CWM) values of 10 single traits, and beta diversity based on 2 dissimilarity indices (Jaccard and Bray–Curtis). The overall effects of zone management were weak or insignificant. Species richness and the CWMs of most traits were not associated with zone (p > 0.08). Reserve itself was a strong factor influencing bird traits. Dissimilarity indices also showed variations in bird community composition between reserves in the north region and those in the south region, which were largely contributed by the turnover component of beta diversity (p ≥ 0.06 for nestedness and p ≤ 0.03 for turnover in both dissimilarity indices). The dominance of turnover indicates that these reserves could be equally important to maintain regional bird diversity, requiring a multiple-site management plan. Our study also suggests that current zoning designations of the five reserves may not be as effective in conserving bird species diversity and traits; however, caution is needed due to the limitations of our study design, such as potential observer effect and insufficient sampling effort. [ABSTRACT FROM AUTHOR]

Aim: Protected areas (PAs) in China have typically been designed by considering one or several focal taxa (e.g., relict plant and vertebrate species), but the effectiveness of these "protective umbrellas" in safeguarding insects remains unclear. In this study, we aim to investigate the distribution and diversity of endemic true bugs for four family groups (i.e., Miridae, Lygaeoidea, Pentatomidae, and Reduviidae) in China, the environmental factors shaping these diversity patterns, and the effectiveness of China's PAs in safeguarding their diversity. Location: China. Methods: We mapped the spatial distributions of 1028 endemic true bugs in China using stacked species distribution models and pixel grids of observed points. The environmental factors that influence diversity patterns across China were explored by generalized linear models and random forest models. The effectiveness of PAs in safeguarding species distributions was evaluated by the Zonation platform. Main results: We found that most (84.9%) diversity hotspots for total species were located in mountainous areas of southern China. Additionally, the diversity patterns are shaped by the combined effects of different environmental factors, with the minimum temperature of the coldest month, annual precipitation, and elevation showing the strongest effects. On average, Chinese PAs covered 10.2% of the distribution areas of these endemic true bugs. Main conclusions In general, our research identifies the important roles of mountainous areas in southern China in maintaining species diversity. Moreover, our research also suggests that PAs in China could not provide sufficient protection for this diversity. Protecting these endemic true bugs diversity should be valued more in mountainous areas of southern China. [ABSTRACT FROM AUTHOR]

The Amur tiger (Panthera tigris altaica) is critically endangered and also the subspecies of the tiger with the most restoration potential in China. It is challenging to protect large‐ranging carnivores like tigers under increasing pressure of human development. To provide a more technically robust foundation for tiger habitat conservation prioritization, we conducted a comprehensively empirical analysis based on a broadly collected occurrence dataset of tigers and their prey. We modeled tiger distribution by running an ensemble model integrating nine different algorithms. We found that the ensemble model performed well and outperformed any individual model regarding the discrimination ability. We used cumulative resistant kernel analysis to identify core habitats as with high predicted movement density and used factorial least‐cost paths to model corridors among tiger occurrence locations. We found that core habitats for Amur tigers are distributed in three mountain areas, namely, eastern Wanda Mountain, southern Zhangguangcailing, and Laoyeling‐Dalongling. We found significant protection gaps as existing protected areas only cover less than one‐fourth of predicted core habitats, but this proportion will rise significantly with the establishment of the Northeast China Tiger and Leopard National Park. Furthermore, we ranked spatial priorities for the expansion of the protected area network, simultaneously considering biological and socioeconomic dimensions under the Zonation framework. Our study presented the most up‐to‐date and detailed maps of the predicted potential distribution and area of the most important habitats for the Amur tigers in China, which can provide quantitative guidance in the effort to maximize the efficiency of conservation initiatives at a regional scale. [ABSTRACT FROM AUTHOR]

Zonation is a typical pattern of soil distribution and species assembly across riparian habitats. Microorganisms are essential members of riparian ecosystems and whether soil microbial communities demonstrate similar zonation patterns and how bulk and rhizosphere soil microorganisms interact along the elevation (submergence stress) gradient remain largely unknown. In this study, bulk and rhizosphere (dominant plant) soil samples were collected and investigated across riparian zones where the submergence stress intensity increased as the elevation decreased. Results showed that the richness of bacterial communities in bulk and rhizosphere soil samples was significantly different and presented a zonation pattern along with the submergence stress gradient. Bulk soil at medium elevation that underwent moderate submergence stress had the most abundant bacterial communities, while the species richness of rhizobacteria at low elevation that experienced serious submergence stress was the highest. Additionally, principal coordinate analysis (PCoA) and significance tests showed that bulk and rhizosphere soil samples were distinguished according to the structure of bacterial communities, and so were bulk or rhizosphere soil samples from different elevations. Redundancy analysis (RDA) and Mantel test suggested that bacterial communities of bulk soil mainly relied on the contents of soil organic matter, total carbon (TC), total nitrogen (TN), sodium (Na), calcium (Ca) and magnesium (Mg). Contrastingly, the contents of Na and Mg were the main factors explaining the variation in rhizobacterial community composition. Correlation and microbial source tracking analyses showed thatthe relationship of bulk and rhizosphere soil bacteria became much stronger, and the rhizosphere soil may get more bacterial communities from bulk soil with the increase in submergence severity. Our results suggest that the abiotic and biotic components of the riparian ecosystem are closely covariant along the submergence stress gradient and imply that the bacterial community may be a key node linking soil physiochemical properties and vegetation communities. [Display omitted] • Periodic submergence made bacterial community composition to be a zonation pattern. • The abundances of soil bacteria showed distinct patterns with submergence stress changed. • SOM, TC, TN, Na, Ca and Mg were the main drivers of bacterial assemblage in bulk soil. • Rhizobacteria of bermudagrass were mainly shaped by environment factors of Na and Mg. • Relevance of bulk and rhizosphere soil bacteria increased as submergence stress enhanced. [ABSTRACT FROM AUTHOR]

Extensive studies have shown that the relationship between flooding duration and wetland plant biomass is context specific. The underlying mechanisms, however, are uncertain. A likely explanation is that flooding has both direct effects by exerting stress on plants and indirect effects by affecting soil nutrient availability. The net effect would be context‐specific and might depend on season. Here, we tested two potential factors mediating the flooding effects on wetland plant biomass: soil nutrient availability and season.We carried out a field investigation in the lakeshore meadows of the Poyang Lake floodplain, China, along a flooding duration gradient during the non‐flooding period. To test the interaction between flooding duration and soil nutrients, we carried out a nutrient (N and P) addition experiment in two types of communities with different flooding durations.The above‐ground biomass (AGB) decreased with flooding duration in winter but had a quadratic response in spring, suggesting that the direct negative effect of flooding was stronger in winter than in spring. Soil total N content, total P content, and N:P ratio showed quadratic responses to flooding duration.Our results supported the hypotheses that the influence of nutrient limitation decreased with flooding duration and was greater in spring than in winter. The evidence showed that, with longer flooding duration and in winter than in spring, the correlations between AGB and soil nutrient content were weaker, leaf N and P content of Carex cinerascens were stronger, and AGB response ratio to nutrient addition was lower. Meanwhile, the relative importance of N versus P to wetland plant biomass varied with flooding duration.Consequently, indirect effects of flooding duration on AGB via soil nutrient availability were much less important than direct effects in winter or with long flooding duration, but were more important in spring or with short flooding duration. Therefore, the effects of flooding on wetland plant biomass depended on flooding duration, soil nutrient availability, and season. [ABSTRACT FROM AUTHOR]

• Discuss indicators of SCP theory and application to implementable planning. • Prioritization by the minimum-cost and maximal-beneficial problems of SCP theory. • Marxan and Zonation are used to prioritize two scenarios respectively. • Prioritization based on SCP theory can be more implementable than current methods. Currently, research on the methodological framework for identifying conservation priority areas in China's territorial ecological conservation planning pays limited attention to the plan's implementability. Therefore, in this study, we developed a new prioritization framework for planning implementation based on systematic conservation planning (SCP) theory, which not only incorporated multiple types of key indicators for conservation prioritization assessment but also provided managers with differentiated decision-making scenarios, including the use of the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, the Marxan model, and the Zonation model. We applied the framework in Xi'an, a megacity in northwest China. To evaluate the effectiveness of the new framework, a comparison was made between two scenarios: the systematic conservation planning scenarios (SCPs) based on the new framework and the ecologically important scenarios (EIs) based on the previous main methodology (which integrates the level of ecosystem service provision and ecological vulnerability). Under SCPs and EIs, the areas of conservation priority are 2,118.35 km2 and 4,447.15 km2, respectively, and SCPs gained slightly fewer conservation benefits than EIs but caused less loss of economic benefits in terms of GDP (27.8884 million yuan and 494.3732 million yuan for SCPs and EIs, respectively). This shows that the new framework can help minimize conservation costs while satisfying each conservation benefit as much as possible compared to previous approaches, thus contributing to the implementability of the plan. In future works, the application scenarios of the multiscenario prioritization framework based on SCP theory can be further expanded, and flexible solutions can be provided for the implementation of landscape planning in similar areas facing urgent conservation needs. [ABSTRACT FROM AUTHOR]

As one of the important elements of controlling the redox system within the hyporheic and hypolentic zone, sulfur is involved in a series of complex biogeochemical processes such as carbon cycle, water acidification, formation of iron and manganese minerals, redox processes of trace metal elements and a series of important ecological processes. Previous studies on biogeochemistry of the hyporheic and hypolentic zones mostly concentrated on nutrients of nitrogen and phosphorus, heavy metals and other pollutants. Systematic study of biogeochemical behavior of sulfur and its main controlling factors within the lake hypolentic zone is very urgent and important. In this paper, a typical desert plateau lake, Dakebo Lake in northwestern China, was taken for example within which redox zonation and biogeochemical characteristics of sulfur affected by hydrodynamic conditions were studied based on not only traditional hydrochemical analysis, but also environmental isotope evidence. In the lake hypolentic zone of the study area, due to the different hydrodynamic conditions, vertical profile of sulfur species and environmental parameters differ at the two sites of the lake (western side and center). Reduction of sulfate, deposition and oxidation of sulfide, dissolution and precipitation of sulfur-bearing minerals occurred are responded well to Eh, dissolved oxygen, pH, organic carbon and microorganism according to which the lake hypolentic zone can be divided into reduced zone containing H2S, reduced zone containing no H2S, transition zone and oxidized zone. The results of this study provide valuable insights for understanding sulfur conversion processes and sulfur biogeochemical zonation within a lake hypolentic zone in an extreme plateau arid environment and for protecting the lake-wetland ecosystem in arid and semiarid regions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Chakabeishan pegmatitic rocks are pegmatite type based on the CMS classification and have six internal vertical zonations. • The magma was originated from ancient metasedimentary rocks and finally intruded in the Late Triassic controlled by Paleo-Tethys Ocean subduction process. • Vertical zones are formed by mild crystal fractionation, melt-fluid immiscibility and metasomatism after emplacements. In recent years, a newly rare metal metallogenic belt has been discovered in the North Qaidam Terrane (NQT), NW China, of which the Chakabeishan (CKBS) Li-Be pegmatitic deposit is an important part. In this study, CMS (chemical composition-mineral assemblage-structural geology) classification is applied on CKBS pegmatitic rocks, based on their CMS features, the rocks are identified as pegmatite type. The CKBS pegmatites exhibit unique internal vertical zonation characteristics, and six zones are identified: biotite-muscovite-albite zone, graphic zone, layered tourmaline-albite zone, beryl-albite zone, spodumene-beryl-albite zone, and spodumene-albite zone. In this article, we present U-Pb zircon ages, Hf isotope dating, whole-rock geochemistry, and mineral geochemistry to elucidate pegmatite evolution. The zircon U-Pb ages of the spodumene-bearing pegmatite are 258.1 ± 1.4 Ma and 219.6 ± 6.3 Ma, indicate that the magma experienced two stage crystallization. The negative εHf(t) values range from −14.55 to −9.4 with T 2DM model ages of 1845–2173 Ma, indicate that the magma originated from ancient rocks anatexis. The first anatectic event occurred during the Paleo-Tethys Ocean subduction process, as the magma originated from the anatexis of ancient metasedimentary rocks, provided enough rare elements (Li, Be, Nb, Ta). However, the second anatectic event occurred during post-orogenic stage and intruded in the host rocks forming pegmatite veins in the Late Triassic. Subsequently, intruded magma experienced mild fractionated crystallization, melt-fluid immiscibility and subsequent metasomatism, forming the vertical zonings. [ABSTRACT FROM AUTHOR]

We propose an improved planning method for priority protected areas (PPAs) to conserve endangered plant species that are threatened by climate change and human disturbance. Recent researches have shown that the actual approaches used in planning PPAs are useful for the conservation of endangered plants. The next required step is to determine how to protect endangered plants effectively in PPAs. Here, we used the case of 84 endangered plants in China to integrate conservation management into the planning of PPAs. First, we identified locations for proposed PPAs based on current and future suitable habitats of species, based on shifts due to climate change, as modelled by Maxent; secondly, we classified the species into different clusters based on the value of protecting them and the factors that threaten them; finally, we determined the best regions for conservation management. We found that species with high material, medicinal, and scientific research values of protection were threatened by over-exploitation and excess reclamation in PPAs. The best candidate PPAs were distributed mainly in southern China-the provinces of Fujiang, Guangxi, Guangdong, Fujian, Hunan, Zhejiang and Guizhou held large potential for the protection of endangered plant species. Given the attention that we paid to conservation management for the planning of PPAs, and the practical value of study, our method will provide an important point of reference for the implementation of policy to protect endangered plants from the effects of climate change, along with information about the values of protecting species and the factors that threaten them. [ABSTRACT FROM AUTHOR]

Climate change has greatly affected the natural habitats of wild plants, especially vulnerable species. However, methods to properly assess priority protected areas (PPAs) that consider climate change have not been established. The distribution of Fraxinus mandshurica in northeast China was assessed, and our goal was to develop model-based strategies for the assessment of PPAs in consideration of climate change. To achieve this goal, we mapped the current and future suitable habitat distributions of F. mandshurica and planned PPAs based on 4 field surveys in northeast China. The models used in this study included a species distribution model (Maxent), systematic conservation planning model (Zonation), and geographic information system (ArcGIS 10.0). To promote sustainable development, the current and future suitable habitats of F. mandshurica must be integrated into the assessment of PPAs; however, the conservation areas of F. mandshurica in existing nature reserves cannot realize the conservation criterion of the Global Strategy for Plant Conservation (GSPC). In the eastern and northeastern regions of northeast China, the suitable habitats are predicted to migrate slightly northwards in the future. The methods used in this study are adequate for the assessment of PPAs and may provide a reference for the conservation and management of vulnerable plants. [ABSTRACT FROM AUTHOR]

China's forests were severely degraded by human activities during the latter half of the 20th century. Therefore, China enacted ambitious programs of natural forest protection and afforestation to protect and expand forests. Yet it is unclear how the programs, especially the designation of forest reserves, have affected forest cover and fragmentation. We evaluated the effectiveness of China's national forest reserves designated since 1990 in conserving forests, by analyzing four forest metrics (i.e., percentage forest cover, mean forest patch size, mean forest patch radius of gyration, and forest patch cohesion index) derived from a newly produced 30 m annual China land cover dataset from 1990 to 2019. We found that overall forest cover increased and fragmentation decreased from baseline years, when reserves were designated, to 2019 in both reserves and their surrounding areas, and only the increase in forest cover relative to baseline was significantly greater in reserves than in surrounding areas. The designation time of reserves under national protection had no considerable effect on changes in the four metrics, but for zonation, the core zone showed a significantly higher increase in forest patch cohesion index relative to baseline than the buffer and transition zones. Nevertheless, forest cover declined and fragmentation increased in highly forested reserves, suggesting destructive human activities and ineffective management. Thus, forest protection and regeneration programs were moderately successful. We recommend that there is significant improvement needed to ensure greater protection of existing forests and reduction of threats to promote effective management. • The nature reserve program showed effectiveness in conserving forests in China. • There was better protection and recovery of forest cover than reducing fragmentation. • Destructive human activities may cause forest declines in highly forested reserves. [ABSTRACT FROM AUTHOR]

Prioritizing threatened species protection has been proposed as an efficient response to the global biodiversity crisis. We used in-situ conservation data to predict the potential habitat area of four flagship species: the giant panda (Ailuropoda melanoleuca), golden monkey (Rhinopithecus roxella quinlingensis), takin (Budorcas taxicolor bedfordi), and crested ibis (Nipponia nippon). We then designed systematic conservation planning schemes for various scenarios given species habitat preferences and anthropogenic activities and conducted a cost-effectiveness assessment. Broadly, the geographical distributions of suitable habitats for giant pandas, golden monkeys, and takins exhibited high spatial congruence (correlation coefficients of 0.59–0.90), and areas of high congruence were concentrated in the northern portion of the Qinling Mountains at high elevation (>1500 m). By contrast, the crested ibis was negatively correlated in space with its sympatric species (−0.47 to −0.29). Crested ibis habitats were clustered in the southern portion of the region at low elevation (<1500 m). A hypothetical conservation priority area (CPA) based on the giant panda, golden monkey, and takin included 39.64% of the Qinling Mountains and 100%, 99.99%, 99.59%, and 7.84% of the suitable habitats for giant pandas, golden monkeys, takins, and crested ibises, respectively. The same area included 99.07%, 70.87%, and 39.96% of the highly important areas for the ecosystem services of biodiversity conservation, water supply, and soil retention, respectively, and only 4.62%, 16.83%, and 13.4% of the area were associated with high-density residential area, impervious surfaces, and cropland, respectively. Therefore, we conclude that a CPA approach based on the specialist species could result in effective, low-cost biodiversity conservation in the Qinling Mountains. However, we note that existing protected areas account for only 26.52% of the CPA. We recommend that the main area of the proposed Qinling National Park should be based on the CPA developed here. • Crested ibis habitat was different from other flagship species, which with considerable areas of intensive human activities. • Protecting giant pandas alone, or any flagship species, was not sufficient for long-term protection of Qinling-biodiversity. • Protection cost should be considered in the designation of the conservation prioritization schemes. [ABSTRACT FROM AUTHOR]

The longitudinal patterns of the macroinvertebrate community in the Xiangxi Bay of the Three Gorges Reservoir (TGR) were investigated during the second (2nd) and third (3rd) impoundment stages (October 2006-July 2010), to test the effects of increased water level fluctuations (WLF) on the macroinvertebrates. By comparing to the former reports of the first (1st) impoundment stage (inter-annual WLF 4 m), we found that oligochaetes dominated in three different stages in the Xiangxi Bay. However, the total abundance of macroinvertebrates showed a dramatical decline from the 1st to 2nd stage (inter-annual WLF 11 m), but changed slightly from the 2nd to 3rd stage (inter-annual WLF 30 m). This indicated that higher WLF in the 2nd stage had already greatly reduced the macroinvertebrates abundance, thereby the disturbance in the 3rd stage could only slightly affect the already reduced abundance. Three longitudinal zones (the mainstream zone, the lacustrine zone and the transitional zone) were found based on the macroinvertebrate density, biomass, and taxa richness, combined with the geographical location of each site. Significant differences in density and biomass of macroinvertebrate were found among different zones ( P < 0.05), yet no significant difference was found in taxa richness ( P > 0.05). Two-way indicator species analysis showed that the community type in most sites varied in different seasons from the 2nd stage, exhibiting a dynamic zonation pattern, which differed with the stable pattern of the 1st stage. This seasonal feature was coupled to the seasonal changes of the WLF. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Tectono-geochemical samples were systematically collected from 5 drillcores along the No. 304 exploration line and at the −310 m level under the pit in the mining area, totalling 705 samples from the metamorphic rocks, granites, altered rocks and orebodies, and were determined for their contents of 20 kinds of elements including Au, Ag, As, Sb, Hg, Cu,-Pb, Zn, Sn, Bi, Mo, Co, Ni, Mn, Cr, V, Ti, Ba, Rb, Sr, etc. By using the Surfer software the geochemical exploration line profile maps for the 20 kinds of elements and the curves for the element geochemical contents of individual ore vein groups were established. In conbination with the geochemical map analytical method and Gregorian's zoning index calculation method, the vertical, longitudinal and lateral zonation sequences of the elements were ascertained and the geochemical three-dimentional zonation model of the primary halos was established on the basis of the analysis of metallogenic structures and alteration zonation. Coupled with the results of analysis of the geology and geochemistry data, it may be concluded that the process of alteration of granites in the mining area is also accompanied with the process of gold enrichment and mineralization. With the intensification of alteration of granites from granite →potash feldspathization granite →sericite-quartz alteration granite, sericite-quartz rocks →beresitized granite, pyrite sericite-quartz rock, silicified granite →gold ore, the contents of thiophile ore-forming elements such as Au, Ag, As, Cu, Bi, Mo, Pb, Sb, Hg, and Sn tended to increase. Factor analysis of trace elements indicated: factor F2 (Au, Ag, Cu, Sn, As) represents the element association brought in at the main stage of hydrothermal metallogenesis; factor F4 (Bi, Sb) and factor F5 (Pb, Zn) represent the ore-forming element association supperposed during the late stage of Au-bearing sulfides. By using the Gregorian's zoning index and map analysis method we have ascertained the primary halo axial zonation sequence (form frontal halo →tail halo): Pb, Zn, Mn, Ba, Sr, Rb, As, Sb, Ag, Cu, Sn, Mo, Au, Bi, Hg, Ti, Cr, V, Ni, and Co. The geochemical anomalies in the mining area display a tendency of lateral plunging to WS, which is consistent with the lateral plunging of orebodies and mineralization alteration zone. Comprehensive analysis of the results of investigations on ore-controlling structures, mineralization-alteration zonation and geochemical zonation of the primary halos indicates that the gold orebodies in this area are still of greater extension. [ABSTRACT FROM AUTHOR]

Abstract: Major abrupt environmental pollution accidents can cause huge socio-economic losses and seriously damage the environment. Zoning of abrupt environmental pollution risk can greatly aid decision-making and governance, with a view to preventing and mitigating such pollution accidents in a typical mega-city. The present paper proposes a risk system for environmental pollution accidents, which comprises an index system and a quantitative risk assessment model of environmental risk zonation. The system is based on data on past abrupt environmental pollution accidents, regional environmental risk theories, and natural disaster risk theories. An Abrupt Environmental Pollution Risk Zonation (AEPRZ) approach, applicable to a large area, is proposed, which involves the selection of appropriate zonation principles, units, and indexes for the measurement and classification of environmental risk, amending the zonation, and then mapping risk zonation with GIS tools. The AEPRZ approach is applied to the risk zonation of environmental pollution accidents in Minhang District, Shanghai, China, which was divided into four zones according to high, medium, low, and very low degrees of risk. In each zone, each of the socio-economic, hazard, vulnerability, and overall risk factors is assigned a specific degree of risk, thus providing a basis for the implementation of control measures as part of environmental risk prevention management. [ABSTRACT FROM AUTHOR]

The article presents a study that deals with variations in intertidal assemblages and zonation patterns between vertical artificial seawalls and natural rocky shores in Victoria Harbour, Hong Kong. Included in the study are three vertical artificial seawalls and three natural rocky shores. Findings revealed that the chiton Acanthopleura japonica and the oyster Saccostrea cucullata and barnacle Amphibalanus were abundant in artificial seawalls while natural rocky shores supported a greater abundance of the false limpet Siphonaria laciniosa and the barnacle Tetraclita squamosa. The authors attributed the differences in zonation patterns of species to the vertical orientation of artificial seawalls.

Abstract: The Early Triassic paleogeographical setting of the Chaohu section in China was in a deep part of the Yangtze platform and this has resulted in a rather complete Lower Triassic sequence with rich ammonoid and conodont successions. Three Lower Triassic sections, West Pingdingshan, North Pingdingshan and South Majiashan, have been sampled in detail for a systematic conodont study. Eight conodont zones are recognized; in ascending order these are the zones of Hindeodus typicalis, Neogondolella krystyni, Neospathodus kummeli, Neospathodus dieneri, Neospathodus waageni, Neospathodus pingdingshanensis, Neospathodus homeri, and Neospathodus anhuinensis. These are correlated with the sequences in North America and other areas of the world. The succession provides a good basis for the definition of the global stratotype of the Induan–Olenekian boundary (GSSP), which has been proposed at the base of the Neospathodus waageni Zone in West Pingdingshan. Seven new species are introduced: Neospathodus chaohuensis, N. chii, N. concavus, N. eotriangularis, N. pingdingshanensis, N. posterolongatus, N. tongi, a new subspecies N. waageni eowaageni, and three morphotypes of N. dieneri. [Copyright &y& Elsevier]

Debris flow sites were identified at 140 locations in the Xiaojiang Basin in Yunnan province, southwestern China. Their spatial distribution and catchment characteristics are described in detail on the basis of previous research, air photo interpretation, field investigation and mapping using Geographical Information Systems (GIS). Using a statistical approach, a quantitative model of hazards assessment and zonation was developed through synthesis analysis of basin areas, gradients, and the relative reliefs of these debris flow sites. In terms of debris flow hazard assessment, areas within the Xiaojiang Basin can be classified as severe, heavy and light hazard regions. [ABSTRACT FROM AUTHOR]

The Bajiazi Zn–Pb–Ag skarn deposit is located in northwest Liaoning Province, China. The orebodies occur in a contact zone between Yanshanian (170–177.4 Ma) quartz monzodiorite and Middle Proterozoic dolomitic marble of the Gaoyuzhuang Formation as well as along the NW- and NS-trending fault systems in carbonate wall rocks.Metasomatic mineralization zoning in the deposit is very pronounced. From the intrusive contact zone to dolomitic marble along the NW-trending fault system, three ore-bearing skarn zones may be distinguished: magnesian skarn zone (Fe–Mo)→manganoan–magnesian skarn zone (Cu–S–Fe–Pb–Zn–Ag)→manganoan skarn zone (Zn–Pb–Ag). Magnesian skarn is composed of diopside, forsterite, tremolite, spinel, phlogopite, chondrodite, and serpentine, accompanied by magnetite, pyrite, and molybdenite. Manganoan–magnesian skarn consists mainly of manganoan diopside, manganoan tremolite, mangano-anthophyllite, and manganocummingtonite with minor spessartine and pyroxmangite, The associated ore minerals are pyrite, pyrrhotite, and chalcopyrite, with subordinate magnetite, sphalerite, galena, and Ag-bearing minerals. Manganoan skarn is composed chiefly of spessartine, pyroxmangite, magnesian rhodonite, manganocummingtonite, and manganopyrosmalite, with the associated ore minerals sphalerite, galena, alabandite, and Ag-bearing minerals.Studies of fluid inclusions and S, Pb, O, and H isotopic compositions suggest that ore-bearing fluids flowed from the deep contact zone of the intrusion in the southeast to the shallow depth in the northwest with decreasing temperatures, oxidation state, and increasing pH. When the ore-bearing fluids migrated, their frontal part constantly reacted with the dolomitic carbonate wall rocks to form different types of skarn and mineralization. Sulfur and lead (zinc) were mainly derived from the deep lower crust, while the Middle Proterozoic wall rocks may have provided most Al, Si, Mg, Ca, and Mn for the formation of skarns.The zonal model reflecting the variations in metallization assemblage, skarn mineralogy, composition, δ34S isotope values, and fluid inclusion characteristics can be used as a guide to exploration for Zn–Pb–Ag skarn deposits. [Copyright &y& Elsevier]

[Display omitted] • The Jia-Cha ore field belongs to the IS epithermal-porphyry system. • Micro-inclusions of sulfide display a similar zonation with the main metals. • The ages of mineralization for the epithermal-porphyry system is about 133–135 Ma. • The epithermal Ag-Pb-Zn deposits are genetically related to a porphyry Mo-Cu system. The Jiawula-Chaganbulagen (Jia-Cha) super-large, magmatic-hydrothermal Ag-Pb-Zn ore field in the southern Erguna Block, northeast China, is characterized by a large and well-developed alteration and metallic zonation (~56 km2) that is centered on porphyry Mo-Cu mineralization. The ore field includes two intermediate-sulfidation epithermal Ag-Pb-Zn deposits, which are located at Jiawula and Chaganbulagen. A weighted-mean molybdenite Re-Os age of 135.1 ± 2.1 Ma (MSWD = 0.16) and a molybdenite 187Re-187Os isochron age of 135.4 ± 2.3 Ma (MSWD = 0.44) were obtained for the Mo-Cu mineralization, and the host quartz monzonite porphyry yielded a weighted-mean zircon U-Pb age of 141.9 ± 2.4 Ma (MSWD = 0.044). Geochronological data suggest that the epithermal mineralization occurred at 135 to 133 Ma, and the porphyry age is little older than the porphyry-epithermal mineralization. The porphyry Mo-Cu mineralization is interpreted as the hydrothermal center of the ore field, based on the metal zonation:Mo-Cu → Zn-Cu → Zn-Cu-Pb-(Ag) → Zn-Pb-Ag-(Cu) → Ag (Au)-Pb-Zn → Ag, with vertical ore minerals zonation from deeper molybdenite-chalcopyrite to shallower sphalerite-galena-chalcopyrite through molybdenite-chalcopyrite-sphalerite. Trace element analyses by LA-ICP-MS of pyrite and pyrrhotite show that micro-inclusions exhibit similar "ore field-scale" trace element zonation: Bi-Ag → Bi-Sb-Ag → Sb-Ag. Geological and geochronological evidence indicates that the Jia-Cha epithermal system is genetically related to the adjacent porphyry Mo-Cu mineralization. XRF element mappings of the replaced ores revealed that late ore stage oxidizing fluids dissolved the early chalcopyrite at depth, and then replaced the sulfides in the main ore stage. Porphyry-epithermal mineralization system in the Jia-Cha ore field is significant for further exploration for porphyry Mo-Cu and epithermal Ag-Pb-Zn deposits in northeast China. [ABSTRACT FROM AUTHOR]