The harsh natural environment of Antarctica has led to a lack of research on the presence and transport mechanisms of organophosphate esters(OPEs) within its ecosystem.In this study,we analyzed levels of 11 OPEs in ai...The harsh natural environment of Antarctica has led to a lack of research on the presence and transport mechanisms of organophosphate esters(OPEs) within its ecosystem.In this study,we analyzed levels of 11 OPEs in air,soil,and vegetation samples collected during the 2018-2019 Chinese 35th Antarctic Scientific Expedition.Additionally,a level Ⅲ fugacity model was developed to simulate the movement and fate of detected OPEs in the air,soil,and vegetation of the Fildes Peninsula.Our model indicated that the primary OPEmigration pathway was from the atmosphere to the soil.OPE transportation primarily occurred through atmospheric wet deposition and rainwater dissolution.Among the 20 transport and transformation processes,atmospheric degradation was the most significant loss mechanism.The proposed model provides a method for continued investigation into the fate of OPEs in the Fildes Peninsula ecosystem.展开更多
The winter temperature variability of the Antarctic Peninsula(AP)has been proven to be influenced by sea surface temperature(SST)anomalies over the Tasman Sea.Using outputs over an extended time period from historical...The winter temperature variability of the Antarctic Peninsula(AP)has been proven to be influenced by sea surface temperature(SST)anomalies over the Tasman Sea.Using outputs over an extended time period from historical experiments,the skills of CMIP6 models in simulating the atmospheric responses to Tasman Sea SST are evaluated in this study,with an emphasis on the relationships with AP temperatures.The spatial correlation coefficient and normalized standard deviation are used as the evaluation metrics.Corresponding results suggest that the majority of CMIP6 models can capture the basic spatial distributions of Tasman Sea-related teleconnections across the Southern Hemisphere extratropical region,featuring a Pacific–South America-like pattern.However,the overestimation of atmospheric interannual variability and the underestimation of oceanic interannual variability in CMIP6 models result in a considerable amplification of the atmospheric responses to SST anomalies.The model uncertainty in depicting the relationships between Tasman Sea SSTs and AP surface temperatures,as well as the associated teleconnections,can partially be attributed to variations in grid resolutions among models.Additionally,further analysis of the Antarctic sea ice shows that the Tasman Sea SST may contribute to the interannual variability of the Antarctic dipole in CMIP6.展开更多
To investigate the effect of typhoon path translation on storm surge augmentation,the storm surge during Typhoon 1909 Lekima in the East China Sea is simulated using Delft 3D.The model sets up three scenarios to analy...To investigate the effect of typhoon path translation on storm surge augmentation,the storm surge during Typhoon 1909 Lekima in the East China Sea is simulated using Delft 3D.The model sets up three scenarios to analyze the path’s effect on storm surge in the Shandong Peninsula Sea by shifting the typhoon path to the east and west.Results show that the areas of maximum storm surge in each scenario are located on both sides of the typhoon path and shift along with its movement.When the typhoon path shifts eastward,the maximum storm surge intensifies at Zhifu Island station 8 hours earlier.Conversely,a westward shift in the typhoon track leads to a maximum storm surge increase at Shidao Island station 12 hours earlier.Other scenarios exhibit minimal deviation from the original route.Typhoons penetrating deep inland can induce substantial storm surges,with the most extensive surge area situated in the western part of the Shandong Peninsula.展开更多
The lithospheric thinning and huge gold mineralization in the Jiaodong Peninsula is intensively studied,aiming to better understand the geodynamic setting of the magmatic petrogenesis and the relationship between magm...The lithospheric thinning and huge gold mineralization in the Jiaodong Peninsula is intensively studied,aiming to better understand the geodynamic setting of the magmatic petrogenesis and the relationship between magmatism and large-scale mineralization.Thus,we conducted detailed research on the Weideshan intrusions in the Jiaodong region,including fi eld investigations,geochemical,geochronological and Hf isotope analysis,to reveal the tectonic implications for the destruction of the eastern North China Craton(NCC).The Weideshan intrusions consist of quartz monzodiorite,quartz monzonite and monzogranite.The SHRIMP zircon U-Pb dating results show that the Weideshan intrusions are emplaced at 115–112 Ma,namely,in the late Early Cretaceous period.Rocks of Weideshan intrusions are high-K calc-alkaline series and metaluminous granites.The trace elements are characterized by enrichment of Rb,Ba,Sr and LREE,with unobvious Eu anomalies and depletion of Nb,Ta,Zr,Hf and Ti.The contents of Ba and Sr are(913.00–1562.00)/1199.29μg/g and(373.00–793.00)/536.71μg/g,respectively,showing the features of high Ba–Sr granites(HBS).Development of numerous dark enclaves and negativeεHf(t)values(−17.93 to−12.19)indicate that the Weideshan granites originate from the mixture of crustal-derived felsic magma from partial melting of the Paleoproterozoic crust and alkali-rich magma from the enriched mantle.The generation of the Weideshan granites was closely related to the asthenospheric upwelling during the lithosphere thinning of the NCC in the late Mesozoic.展开更多
Since its description,the taxon Ophrys sphegodes subsp.grammica has been considered endemic to Greece.The morphological and chorological data of this taxon have been overlooked because the name has been used as a syno...Since its description,the taxon Ophrys sphegodes subsp.grammica has been considered endemic to Greece.The morphological and chorological data of this taxon have been overlooked because the name has been used as a synonym for O.sphegodes subsp.taurica in most publications and online databases.Recently discovered Ophrys populations in Serbia were identified as O.sphegodes subsp.grammica.As these populations represent the northernmost point of distribution of this taxon,we provided data on the morphology,flowering season,and ecology.To determine the taxonomic status of this taxon,we performed comparative morphological analyses,comparing them to other populations of affined taxa(O.sphegodes subsp.grammica,O.sphegodes subsp.taurica,and O.sphegodes subsp.sphegodes).The analysis included 23 morphometric characters,performed on a total of 120 individuals.Examined populations of O.sphegodes subsp.grammica are closely associated with populations of O.sphegodes subsp.sphegodes,with near overlap in the values of the characteristics evaluated,indicating that this subspecies is more morphologically similar to the typical one than to O.sphegodes subsp.taurica.Although O.sphegodes subsp.grammica and O.sphegodes subsp.sphegodes are morphologically similar,the flowers of the first taxon are smaller,as evidenced by the length and width of the stigmatic cavity,as well as the length of the petals and labellum.The labellum of O.sphegodes subsp.grammica is shorter than the dorsal sepal,and this feature distinguishes it from both the typical subspecies and O.sphegodes subsp.taurica,where it is longer.The results of this study clearly show that the name O.sphegodes subsp.grammica should not be equated with O.sphegodes subsp.taurica,since it is a morphologically distinct and well-defined taxon.展开更多
The Taishang-Shuiwangzhuang gold deposit is located in the southeastern margin of Linglong gold field in the northern part of the Zhaoping Fault metallogenic belt of the Jiaodong gold province-the world’s third-large...The Taishang-Shuiwangzhuang gold deposit is located in the southeastern margin of Linglong gold field in the northern part of the Zhaoping Fault metallogenic belt of the Jiaodong gold province-the world’s third-largest gold metallogenic area.Major prospecting breakthroughs have been made at the depth of 600‒2500 m in recent years,with cumulative proven gold resources exceeding 700 t.Based on a large number of exploration data,the main characteristics of the deposit are described in detail,and the spatial coupling relationship between ore-controlling fault and main orebodies is discussed.The main orebodies occur as regular large veins,exhibiting branching and combination,expansion and contraction,and pinch-out and reoccurrence.They extend in a gentle wave pattern along their strikes and dip directions and generally have a pitch direction of NEE and a plunge direction of NEE.As the ore-controlling fault,the Zhaoping Fault has the characteristics of wave-like fluctuation,with its dip angle presenting three steps of steep-slow transition within the depth range of 2500 m.The gold mineralization enrichment area is mainly distributed in the step parts where the fault plane changes from steeply to gently.The ore-forming age,ore-forming fluid and ore-forming material sources and the genesis of the ore deposit are analyzed based on the research results of ore deposit geochemistry.The ore-forming fluids were H_(2)O-CO_(2)-NaCl-type hydrothermal solutions with a medium-low temperature and medium-low salinity.The H-O isotopic characteristics indicate that the fluids in the early ore-forming stage were possibly formed by degassing of basic magma and that meteoric water gradually entered the ore-forming fluids in the late ore-forming stage.The S and Pb isotopes indicate that the ore-forming materials mainly originate from the lower crust and contain a small quantity of mantle-derived components.The comprehensive analysis shows that the Taishang-shuiwangzhuang gold deposit was a typical“Jiaodong type”gold deposit.The strong crust-mantle interactions,large-scale magmatism,and the material exchange arising from the transformation from the ancient lower crust to the juvenile lower crust during the Early Cretaceous provided abundant fluids and material sources for mineralization.Moreover,the detachment faults formed by the rapid magmatic uplift and the extensional tectonism created favorable temperature and pressure conditions and space for fluid accumulation and gold precipitation and mineralization.展开更多
Geochemical compositions can be used to determine the tectonic setting of sedimentary basins,while where the link of source to sink is no longer preserved,detrital zircon age patterns can aid in resolving the original...Geochemical compositions can be used to determine the tectonic setting of sedimentary basins,while where the link of source to sink is no longer preserved,detrital zircon age patterns can aid in resolving the original basin setting.The metasedimentary Legoupil Formation,located at Cape Legoupil and the Schmidt Peninsula,could give a hint for the tectonic evolution of Antarctic Peninsula.In this contribution,we constrain the sedimentary provenance of the Legoupil Formation through geochemistry and detrital zircon U-Pb geochronology.The petrography and geochemical features indicate that the provenance of the Legoupil Formation could be felsic rocks.Detrital zircon grains record a steady supply of Permian and Ordovician material into the Legoupil Formation.The youngest concordant zircon ages of 262 Ma suggest that the depositional time of Legoupil Formation is no older than Late Permian.The detrital zircon age spectrum of Legoupil Formation suggests that the Legoupil Formation sediments should be derived from regional sources endemic to western Gondwana prior to its breakup.Together with the previous studies,geochemistry and detrital zircons reflect an active continental margin tectonic setting and the detrital zircon spectra of Legoupil Formation are similar to the ones deposited in forearc tectonic setting.展开更多
The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July 2020.This unique long-lasting extreme event and its origin have attracted considerable attention.Previous studies have suggested tha...The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July 2020.This unique long-lasting extreme event and its origin have attracted considerable attention.Previous studies have suggested that the Indian Ocean(IO)SST forcing and soil moisture anomaly over the Indochina Peninsula(ICP)were responsible for this unexpected event.However,the relative contributions of IO SST and ICP soil moisture to the 2020 mei-yu rainfall event,especially their linkage with atmospheric circulation changes,remain unclear.By using observations and numerical simulations,this study examines the synergistic impacts of IO SST and ICP soil moisture on the extreme mei-yu in 2020.Results show that the prolonged dry soil moisture led to a warmer surface over the ICP in May under strong IO SST backgrounds.The intensification of the warm condition further magnified the land thermal effects,which in turn facilitated the westward extension of the western North Pacific subtropical high(WNPSH)in June‒July.The intensified WNPSH amplified the water vapor convergence and ascending motion over the YRB,thereby contributing to the 2020 mei-yu.In contrast,the land thermal anomalies diminish during normal IO SST backgrounds due to the limited persistence of soil moisture.The roles of IO SST and ICP soil moisture are verified and quantified using the Community Earth System Model.Their synergistic impacts yield a notable 32%increase in YRB precipitation.Our findings provide evidence for the combined influences of IO SST forcing and ICP soil moisture variability on the occurrence of the 2020 super mei-yu.展开更多
Mineral carbonation, which precipitates dissolved carbon dioxide(CO_(2)) as carbonate minerals in basaltic groundwater environments, is a potential technique for negative emissions. The Leizhou Peninsula in southwest ...Mineral carbonation, which precipitates dissolved carbon dioxide(CO_(2)) as carbonate minerals in basaltic groundwater environments, is a potential technique for negative emissions. The Leizhou Peninsula in southwest Guangdong province has extensive basalt, indicating a promising potential for CO_(2) storage through rapid mineralization. However, understanding of the basic geological setting, potential, and mechanisms of CO_(2) mineralization in the basalts of the Leizhou Peninsula is still limited. The mineralization processes associated with CO_(2)storage at two candidate sites in the area are investigated in this paper: Yongshi Farm and Tianyang Basin(of the dried maar lake). Petrography,rock geochemistry, basalt petrophysical properties, and groundwater hydrochemistry analyses are included in the study. Numerical simulation is used to examine the reaction process and its effects. The results show that basalts in the study areas mainly comprise plagioclase, pyroxene, and Fe–Ti oxides, revealing a total volume fraction exceeding 85%. Additionally, small amounts of quartz and fayalite are available, with volume fractions of 5.1% and 1.0%, respectively. The basalts are rich in divalent metal cations, which can form carbonate minerals, with an average of approximately 6.2 moles of metal cations per 1 kg of rock. The groundwater samples have a pH of 7.5–8.2 and are dominated by the Mg–Ca–HCO3 type. The basalts demonstrate a porosity range of 10.9% to 28.8%, with over 70% of interconnected pores. A 20-year geochemical simulation revealed that CO_(2) injection dissolves primary minerals, including anorthite, albite, and diopside, while CO_(2)mineralization dissolves precipitation secondary minerals, such as calcite, siderite, and dolomite. Furthermore, a substantial rise in pH from 7.6to 10.6 is observed in the vicinity of the injected well, accompanied by a slight reduction in porosity from 20% to 19.8%. Additionally, 36.8% of the injected CO_(2) underwent complete mineralization within five years, revealing an increasing percentage of 66.1% if the experimental period is extended to 20 years. The presence of abundant divalent metal cations in basalts and water-bearing permeable rocks in the Leizhou Peninsula supports the potential for mineral carbonation in basalts, as indicated by the geochemical simulation results. Additional research is necessary to identify the factors that influence the CO_(2) mineralization, storage, and sensitivity analysis of basalt in the Leizhou Peninsula.展开更多
There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial carrier.Accurately identifying the differences in spatial characteri...There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial carrier.Accurately identifying the differences in spatial characteristics and influencing factors of each type,is essential for creating urban and rural B&B agglomeration areas.This study used density-based spatial clustering of applications with noise(DBSCAN)and the multi-scale geographically weighted regression(MGWR)model to explore similarities and differences in the spatial distribution patterns and influencing factors for urban and rural B&Bs on the Jiaodong Peninsula of China from 2010 to 2022.The results showed that:1)both urban and rural B&Bs in Jiaodong Peninsula went through three stages:a slow start from 2010 to 2015,rapid development from 2015 to 2019,and hindered development from 2019 to 2022.However,urban B&Bs demonstrated a higher development speed and agglomeration intensity,leading to an increasingly evident trend of uneven development between the two sectors.2)The clustering scale of both urban and rural B&Bs continued to expand in terms of quantity and volume.Urban B&B clusters characterized by a limited number,but a higher likelihood of transitioning from low-level to high-level clusters.While the number of rural B&B clusters steadily increased over time,their clustering scale was comparatively lower than that of urban B&Bs,and they lacked the presence of high-level clustering.3)In terms of development direction,urban B&B clusters exhibited a relatively stable pattern and evolved into high-level clustering centers within the main urban areas.Conversely,rural B&Bs exhibited a more pronounced spatial diffusion effect,with clusters showing a trend of multi-center development along the coastline.4)Transport emerged as a common influencing factor for both urban and rural B&Bs,with the density of road network having the strongest explanatory power for their spatial distribution.In terms of differences,population agglomeration had a positive impact on the distribution of urban B&Bs and a negative effect on the distribution of rural B&Bs.Rural B&Bs clustering was more influenced by tourism resources compared with urban B&Bs,but increasing tourist stay duration remains an urgent issue to be addressed.The findings of this study could provide a more precise basis for government planning and management of urban and rural B&B agglomeration areas.展开更多
The Mesozoic intrusions of the Jiaodong Peninsula,eastern China,host giant gold deposits.Understanding the genesis of these deposits requires the determination of the source of the parental auriferous fluid and the ti...The Mesozoic intrusions of the Jiaodong Peninsula,eastern China,host giant gold deposits.Understanding the genesis of these deposits requires the determination of the source of the parental auriferous fluid and the timing of gold mineralization,which are strongly influenced by the cooling/uplift histories of the hosting intrusions.We performed an integrated U-Pb geochronology study on both zircon and apatite from four major magmatic episodes of the Jiaodong Peninsula.The zircon and apatite U-Pb ages are 156.9±1.2 and 137.2±2.4 Ma for the Linglong intrusion,129.9±1.0 and 125.0±3.8 Ma for the Qujia intrusion,119.5±0.7 and 117.2±1.8 Ma for the Liulinzhuang intrusion,118.6±1.0 and 111.6±1.6 Ma for the Nansu intrusion,respectively.The coupled zircon and apatite data of these granitoids indicate a slow cooling rate(11.9°C/Ma)in the Late Jurassic,and rapid uplift and cooling(35.8-29.2°C/Ma)in the Early Cretaceous.The dramatically increased uplift and cooling period in the Early Cretaceous are contemporaneous with large-scale gold mineralization in the Jiaodong Peninsula.This implies that thermal upwelling of asthenosphere and related tectonic extension played an important role in gold remobilization and precipitation.展开更多
The 2024 Noto Peninsula Earthquake was a significant seismic event that caused extensive damage across the region, characterized by a strong shake, subsequent tsunami, fires, liquefaction, and landslides. An emergency...The 2024 Noto Peninsula Earthquake was a significant seismic event that caused extensive damage across the region, characterized by a strong shake, subsequent tsunami, fires, liquefaction, and landslides. An emergency survey was conducted by our team from January 6 to January 8, 2024, focusing primarily on the impact of the earthquake on road bridges. This preliminary report includes ground motion records from the most affected areas and their response spectra, providing insights into the earthquake's intensity and characteristics. Among the key findings, substantial damage was reported to the long-span bridges connecting Noto Island to the mainland,specifically the Noto Island Ohashi Bridge and the Naka-Noto Agriculture Bridge(Twin Bridge Noto). These bridges are crucial as they serve as the sole access points to Noto Island. Additionally, the survey recorded damage to several other structures, including the Okogawa Bridges, Ouchigata Bridge, and a collapsed old wooden bridge.展开更多
This study presents various approaches to calculating the bearing capacity of spread footings applied to the rock mass of the western corniche at the tip of the Dakar peninsula. The bearing capacity was estimated usin...This study presents various approaches to calculating the bearing capacity of spread footings applied to the rock mass of the western corniche at the tip of the Dakar peninsula. The bearing capacity was estimated using empirical, analytical and numerical approaches based on the parameters of the rock mass and the foundation. Laboratory tests were carried out on basanite, as well as on the other facies detected. The results of these studies give a range of allowable bearing capacity values varying between 1.92 and 11.39 MPa for the empirical methods and from 7.13 to 25.50 MPa for the analytical methods. A wide dispersion of results was observed according to the different approaches. This dispersion of results is explained by the use of different rock parameters depending on the method used. The allowable bearing capacity results obtained with varying approaches of calculation remain admissible to support the loads. On the other hand, the foundation calculations show acceptable settlement of the order of a millimeter for all the layers, especially in the thin clay layers resting on the bedrock at shallow depths, where the rigidity of the rock reduces settlement.展开更多
In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the A...In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the Arabian Peninsula from January 1986 to August 2015. The mean monthly variations of the temperatures at these levels are characterised and established. The magnitudes of the annual trends of the mean temperatures for each site for the selected barometric levels are studied and statistically tested using Mann-Kendall rank statistics at different significance levels. The temperature trends at different pressure levels show that the upper troposphere and lower stratosphere are warming, while the middle troposphere is cooling which is consistent with the findings of other studies. The variations in upper air temperature observed in this study can be attributed to a range of factors, including increasing greenhouse gas concentrations, changes in atmospheric circulation patterns, variations in solar activity, aerosols and volcanic eruptions, and land use and land cover change.展开更多
Leizhou Peninsula, located at southem end of mailand China, has 9 284.3 ha mangrove distributed more than 100 sites along its inlets and open coastlines. This paper presents the surveys on mangrove area in Leizhou Pen...Leizhou Peninsula, located at southem end of mailand China, has 9 284.3 ha mangrove distributed more than 100 sites along its inlets and open coastlines. This paper presents the surveys on mangrove area in Leizhou Peninsula during 2000 and 2008, especially the survey in the eight major mangrove areas in 2002. The flora recorded in mangrove systems includes 69 large algea species, 13 native true mangrove species, nine native semi-mangrove species, and another seven intoduced true mangrove species with Sonneratia apetala as the quickest growing exotic mangrove species dominatant in the mangrove plantations, and more than 100 land flora species, consisting of 17 main mangrove associations. The plant biodiversity habitats remained mainly small patches and diverse, and were becoming worse under the intensive disturbance of human acitivities and coastal pollutions, which decreased the value of mangrove coasts as the important sites for flying-by migrating birds in Leizhou Peninsula. The effective mangrove conservation measures should be implemented.展开更多
The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage...The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage. By setting plot and selecting standard tree, investigation and measurement on height growth, diameter growth, biomass, productivity, and so on, were made in a S. apetala plantation at age of six at Lanbei, Fucheng, Leizhou Peninsula in May 2001. The investigating results showed that the mean annual height growth of plantation was 2.03 m and mean annual growth of diameter at breast height (DBH) was 2.35 cm. There exists a significant correlation between the diameter at ground surface (DGS) and DBH. The average biomass of a single standard tree in dry weight was 95.647 kg/m2. A ratio of above-ground biomass to under-ground biomass was 1.60. The stand biomass of unit area was 22.955 kg/m2, singletree wood volume was 88.23 dm3, and the annual wood volume productivity (PA) of the same year was 0.407. The forest energy accumulation was 424.851 MJ/m2, with annual solar energy fixing rate of 40.68 ×10-7%. It is concluded that S. apetala species had characteristics of outstanding high biomass accumulation and could be used as coastal planting tree species in southern China.展开更多
[Objective] The aim was to study the effects of urbanization and industrialization on farmland system in Shandong Peninsula. [Method] In Shandong Peninsula, the effects were studied and analyzed using remote sensing a...[Objective] The aim was to study the effects of urbanization and industrialization on farmland system in Shandong Peninsula. [Method] In Shandong Peninsula, the effects were studied and analyzed using remote sensing and image interpretation with spatial data analysis and statistic data analysis. [Result] During researching periods in Shandong Peninsula, wasteland area changed from decreasing to increasing; farmland area was declining; orchard and forestry areas were increasing, mainly resulting from political policies and benefits maximization of farmers. Meanwhile, chemical fertilizers and agricultural mechanization are more frequently applied with industrialization and urbanization, leading significant effects on environment, industry and urban. [Conclusion] More policies should be formulated to promote harmonious development of society, economy and environment.展开更多
The provenance of modern beach sands from the Barton and Weaver peninsulas of King George Island,South Shetland Islands,West Antarctica was investigated based on their modal composition and geochemical data.The source...The provenance of modern beach sands from the Barton and Weaver peninsulas of King George Island,South Shetland Islands,West Antarctica was investigated based on their modal composition and geochemical data.The source rocks and provenance tectonic setting are interpreted as volcanic and plutonic rocks formed in the magmatic arc setting.This interpretation is generally consistent with the currently distributed bedrocks in the ice-free areas and tectonic setting of King George Island.However,the composition of beach sands of the Barton and Weaver peninsulas is different from distribution of bedrocks exposed in the ice-free areas of both peninsulas.The present beach sands are interpreted as previous subaqueous moraines that were eroded and transported by advancing glaciers across the both peninsulas and deposited in front of the glacier grounding line.In other words,sand sediments in the beaches of the two peninsulas were not derived from bedrocks currently exposed in ice-free areas,but it is interpreted that they were subaqueous moraines before deglaciation and were mixed with sediment derived from wave erosion of bedrocks and sediments of the paleoshoreline during the isostatic uplift of King George Island.Finally,they were reworked under the current beach environments.展开更多
For understanding the possible deep-seated processes and geodynamic constrains on gold mineralization, comprehensive physicochemical and geochemical studies of gold mineralization have been undertaken within the paleo...For understanding the possible deep-seated processes and geodynamic constrains on gold mineralization, comprehensive physicochemical and geochemical studies of gold mineralization have been undertaken within the paleo-lithosphere framework during the metailogenic epoch from the northwestern part of the Jiaodong Peninsula in this paper. A general image of the paleo-crust has been remained although it has been superimposed and reformed by post-metailogenic tectonic movements. The gold ore deposits occur usually in local uplifts and gradient belts featuring a turn from steep to gentle in granite-metamorphic contact zones, relative uplifts of gradient zones of the Curier isothermal interfaces, depressions of the Moho discontinuity and areas where depth contours are cut by isotherms perpendicularly. Gold mineralization and lithogenesis are characterized by high temperature, low pressure and high strength of thermal flux. The depth of mineralization ranges from 0.8 to 4.5 km. The depth of the top interface of the granitic complex in the metallogenic epoch is about 3 km. There is a low-velocity layer (LVL) at the bottom of the upper crust with a depth close to 19.5 km, which may be a detachment belt in the crust. The appearance of the LVL indicates the existence of paleo-hyperthermal fluid or relics of molten magma chambers, which reflects partial melting within the crust during the diagenetic and metallogenic epochs and the superposition effects of strike-slip shearing of the Taulu fault zone. The subsidence of the Moho is probably attributed to the coupling process of the NW-SE continental collision between North China and the Yangtze Block and the strike-slip movement of the Tanlu fault accompanied with underplating of mantle magma in the northwestern part of the Jiaodong Peninsula. The underplating of mantle magma may result in partial melting and make granite magma transfer upwards. This is favorable for the migration of metallogenic materials from deep to shallow to be enriched to form deposits. Coupling interactions between the strike-slip of the Taulu fault, the underplating of mantle magma, partial melting within the crust, and hyperthermal fluid, etc. may be the important factors controlling the gold mineralization and spatial structures in the metailogenic system.展开更多
Land-use efficiency is low for the urban agglomeration of China. High-speed transportation construction has been an important factor driving land use change. It is critically important to explore the spatial relations...Land-use efficiency is low for the urban agglomeration of China. High-speed transportation construction has been an important factor driving land use change. It is critically important to explore the spatial relationship between the high-speed transportation superiority degree and land-use efficiency. We built a model to evaluate the benefits of convenient high-speed transportation using the relative density of highways and the distance from high-speed rail stations and airports as a metric. We used 42 counties of the Shandong Peninsula urban agglomeration as an example. Land-use efficiency was calculated by a DEA model with capital, labor, economic benefits and environmental benefits as input and output factors. We examined the spatial relationships between high-speed transport superiority degree and land-use efficiency and obtained the following results. First, there are significant spatial differences in the relationships between the high-speed transportation superiority degree and land-use efficiency. Taking the two major cities of Jinan and Qingdao as the hubs, the core surrounding counties show significant spatial relationship between land-use efficiency and the high-speed transportation superiority degree. Spatial correlation declines as the distance from the hubs increases. Land-use efficiency is less than high-speed transportation convenience in areas along the transportation trunks that are distant from the hub cities. Correlation is low in areas that are away from both hub cities and transportation trunk routes. Second, high-speed transportation has a positive relationship with land-use efficiency due to the mechanism of element agglomeration exogenous growth. Third, high-speed transportation facilitates the flow of goods, services and technologies between core cities and peripheral cities as space spillover(the hub effect). This alters the spatial pattern of regional land-use efficiency. Finally, the short-board effect caused by decreased high-speed transport construction can be balanced by highway construction and the proper node layouts of high-speed rail stations and airports, resulting in a well-balanced spatial pattern of land-use efficiency.展开更多
基金supported by the Joint Research Project of Hainan Province(No.ZDYF2024SHFZ085)Hainan Provincial Union Project of Sanya Yazhou Bay Science and Technology City(No.2021CXLH0009)+2 种基金the National Natural Science Foundation of China(Nos.42006195 and 42376234)the Science Technology Project of Yazhou Bay Innovation Institute of Hainan Tropical Ocean University(No.2022CXYZD002)the Scientific Research of Hainan Tropical Ocean University(No.RHDRC202201).
文摘The harsh natural environment of Antarctica has led to a lack of research on the presence and transport mechanisms of organophosphate esters(OPEs) within its ecosystem.In this study,we analyzed levels of 11 OPEs in air,soil,and vegetation samples collected during the 2018-2019 Chinese 35th Antarctic Scientific Expedition.Additionally,a level Ⅲ fugacity model was developed to simulate the movement and fate of detected OPEs in the air,soil,and vegetation of the Fildes Peninsula.Our model indicated that the primary OPEmigration pathway was from the atmosphere to the soil.OPE transportation primarily occurred through atmospheric wet deposition and rainwater dissolution.Among the 20 transport and transformation processes,atmospheric degradation was the most significant loss mechanism.The proposed model provides a method for continued investigation into the fate of OPEs in the Fildes Peninsula ecosystem.
基金jointly supported by the National Natural Science Foundation of China(Grant No.42375027)the Natural Science Foundation of Guangdong Province(Grant No.2023A1515010889)。
文摘The winter temperature variability of the Antarctic Peninsula(AP)has been proven to be influenced by sea surface temperature(SST)anomalies over the Tasman Sea.Using outputs over an extended time period from historical experiments,the skills of CMIP6 models in simulating the atmospheric responses to Tasman Sea SST are evaluated in this study,with an emphasis on the relationships with AP temperatures.The spatial correlation coefficient and normalized standard deviation are used as the evaluation metrics.Corresponding results suggest that the majority of CMIP6 models can capture the basic spatial distributions of Tasman Sea-related teleconnections across the Southern Hemisphere extratropical region,featuring a Pacific–South America-like pattern.However,the overestimation of atmospheric interannual variability and the underestimation of oceanic interannual variability in CMIP6 models result in a considerable amplification of the atmospheric responses to SST anomalies.The model uncertainty in depicting the relationships between Tasman Sea SSTs and AP surface temperatures,as well as the associated teleconnections,can partially be attributed to variations in grid resolutions among models.Additionally,further analysis of the Antarctic sea ice shows that the Tasman Sea SST may contribute to the interannual variability of the Antarctic dipole in CMIP6.
基金supported by the Yantai Science,Technology and Innovation Development Programme(Nos.2023 JCYJ094,2023JCYJ097)the Major Research Grant from the Natural Science Foundation of China(NSFC)(No.42330406)。
文摘To investigate the effect of typhoon path translation on storm surge augmentation,the storm surge during Typhoon 1909 Lekima in the East China Sea is simulated using Delft 3D.The model sets up three scenarios to analyze the path’s effect on storm surge in the Shandong Peninsula Sea by shifting the typhoon path to the east and west.Results show that the areas of maximum storm surge in each scenario are located on both sides of the typhoon path and shift along with its movement.When the typhoon path shifts eastward,the maximum storm surge intensifies at Zhifu Island station 8 hours earlier.Conversely,a westward shift in the typhoon track leads to a maximum storm surge increase at Shidao Island station 12 hours earlier.Other scenarios exhibit minimal deviation from the original route.Typhoons penetrating deep inland can induce substantial storm surges,with the most extensive surge area situated in the western part of the Shandong Peninsula.
基金supported by the Geological Exploration Project Fund of Shandong Province([2018]19,[2019]54,[2021]1,[2022]6).
文摘The lithospheric thinning and huge gold mineralization in the Jiaodong Peninsula is intensively studied,aiming to better understand the geodynamic setting of the magmatic petrogenesis and the relationship between magmatism and large-scale mineralization.Thus,we conducted detailed research on the Weideshan intrusions in the Jiaodong region,including fi eld investigations,geochemical,geochronological and Hf isotope analysis,to reveal the tectonic implications for the destruction of the eastern North China Craton(NCC).The Weideshan intrusions consist of quartz monzodiorite,quartz monzonite and monzogranite.The SHRIMP zircon U-Pb dating results show that the Weideshan intrusions are emplaced at 115–112 Ma,namely,in the late Early Cretaceous period.Rocks of Weideshan intrusions are high-K calc-alkaline series and metaluminous granites.The trace elements are characterized by enrichment of Rb,Ba,Sr and LREE,with unobvious Eu anomalies and depletion of Nb,Ta,Zr,Hf and Ti.The contents of Ba and Sr are(913.00–1562.00)/1199.29μg/g and(373.00–793.00)/536.71μg/g,respectively,showing the features of high Ba–Sr granites(HBS).Development of numerous dark enclaves and negativeεHf(t)values(−17.93 to−12.19)indicate that the Weideshan granites originate from the mixture of crustal-derived felsic magma from partial melting of the Paleoproterozoic crust and alkali-rich magma from the enriched mantle.The generation of the Weideshan granites was closely related to the asthenospheric upwelling during the lithosphere thinning of the NCC in the late Mesozoic.
基金Funding Statement:This research was funded by Ministry of Science,Technological Development and Innovation of the Republic of Serbia(Grants Nos.451-03-137/2025-03/200125&451-03-136/2025-03/200125).
文摘Since its description,the taxon Ophrys sphegodes subsp.grammica has been considered endemic to Greece.The morphological and chorological data of this taxon have been overlooked because the name has been used as a synonym for O.sphegodes subsp.taurica in most publications and online databases.Recently discovered Ophrys populations in Serbia were identified as O.sphegodes subsp.grammica.As these populations represent the northernmost point of distribution of this taxon,we provided data on the morphology,flowering season,and ecology.To determine the taxonomic status of this taxon,we performed comparative morphological analyses,comparing them to other populations of affined taxa(O.sphegodes subsp.grammica,O.sphegodes subsp.taurica,and O.sphegodes subsp.sphegodes).The analysis included 23 morphometric characters,performed on a total of 120 individuals.Examined populations of O.sphegodes subsp.grammica are closely associated with populations of O.sphegodes subsp.sphegodes,with near overlap in the values of the characteristics evaluated,indicating that this subspecies is more morphologically similar to the typical one than to O.sphegodes subsp.taurica.Although O.sphegodes subsp.grammica and O.sphegodes subsp.sphegodes are morphologically similar,the flowers of the first taxon are smaller,as evidenced by the length and width of the stigmatic cavity,as well as the length of the petals and labellum.The labellum of O.sphegodes subsp.grammica is shorter than the dorsal sepal,and this feature distinguishes it from both the typical subspecies and O.sphegodes subsp.taurica,where it is longer.The results of this study clearly show that the name O.sphegodes subsp.grammica should not be equated with O.sphegodes subsp.taurica,since it is a morphologically distinct and well-defined taxon.
基金financially supported by the National Key Research and Development Program of China(Grant No.2023YFC2906900)Key Research and Development Program of Shandong Province(Grant No.2023CXGC011001)+2 种基金The Taishan Scholars Talent Project(TSTP 20240847)The Open Project of Technology Innovation Center for Deep Gold Resources Exploration and Mining,Ministry of Natural Resources(Grant No.SDK202211,SDK202214)Science and Technology Project of Shandong Bureau of Geology and Mineral Exploration and Development(Grant No.KY202208)。
文摘The Taishang-Shuiwangzhuang gold deposit is located in the southeastern margin of Linglong gold field in the northern part of the Zhaoping Fault metallogenic belt of the Jiaodong gold province-the world’s third-largest gold metallogenic area.Major prospecting breakthroughs have been made at the depth of 600‒2500 m in recent years,with cumulative proven gold resources exceeding 700 t.Based on a large number of exploration data,the main characteristics of the deposit are described in detail,and the spatial coupling relationship between ore-controlling fault and main orebodies is discussed.The main orebodies occur as regular large veins,exhibiting branching and combination,expansion and contraction,and pinch-out and reoccurrence.They extend in a gentle wave pattern along their strikes and dip directions and generally have a pitch direction of NEE and a plunge direction of NEE.As the ore-controlling fault,the Zhaoping Fault has the characteristics of wave-like fluctuation,with its dip angle presenting three steps of steep-slow transition within the depth range of 2500 m.The gold mineralization enrichment area is mainly distributed in the step parts where the fault plane changes from steeply to gently.The ore-forming age,ore-forming fluid and ore-forming material sources and the genesis of the ore deposit are analyzed based on the research results of ore deposit geochemistry.The ore-forming fluids were H_(2)O-CO_(2)-NaCl-type hydrothermal solutions with a medium-low temperature and medium-low salinity.The H-O isotopic characteristics indicate that the fluids in the early ore-forming stage were possibly formed by degassing of basic magma and that meteoric water gradually entered the ore-forming fluids in the late ore-forming stage.The S and Pb isotopes indicate that the ore-forming materials mainly originate from the lower crust and contain a small quantity of mantle-derived components.The comprehensive analysis shows that the Taishang-shuiwangzhuang gold deposit was a typical“Jiaodong type”gold deposit.The strong crust-mantle interactions,large-scale magmatism,and the material exchange arising from the transformation from the ancient lower crust to the juvenile lower crust during the Early Cretaceous provided abundant fluids and material sources for mineralization.Moreover,the detachment faults formed by the rapid magmatic uplift and the extensional tectonism created favorable temperature and pressure conditions and space for fluid accumulation and gold precipitation and mineralization.
基金financially co-supported by the National Natural Science Foundation of China(Nos.41530209,41802238)the Chinese Polar Environment Comprehensive Investigation&Assessment Programs(Nos.CHINARE 2015-02-05,CHINARE 2017-04-03)+1 种基金the Young Scientists Fund of Shandong Province(No.ZR2019PD010)the Opening Foundation of Key Laboratory of Mineral Resources Evaluation in Northeast Asia,Ministry of Land and Resources(No.DBY-KF-19-15).
文摘Geochemical compositions can be used to determine the tectonic setting of sedimentary basins,while where the link of source to sink is no longer preserved,detrital zircon age patterns can aid in resolving the original basin setting.The metasedimentary Legoupil Formation,located at Cape Legoupil and the Schmidt Peninsula,could give a hint for the tectonic evolution of Antarctic Peninsula.In this contribution,we constrain the sedimentary provenance of the Legoupil Formation through geochemistry and detrital zircon U-Pb geochronology.The petrography and geochemical features indicate that the provenance of the Legoupil Formation could be felsic rocks.Detrital zircon grains record a steady supply of Permian and Ordovician material into the Legoupil Formation.The youngest concordant zircon ages of 262 Ma suggest that the depositional time of Legoupil Formation is no older than Late Permian.The detrital zircon age spectrum of Legoupil Formation suggests that the Legoupil Formation sediments should be derived from regional sources endemic to western Gondwana prior to its breakup.Together with the previous studies,geochemistry and detrital zircons reflect an active continental margin tectonic setting and the detrital zircon spectra of Legoupil Formation are similar to the ones deposited in forearc tectonic setting.
基金supported by the National Key R&D Program of China(Grant No.2022YFF0801603).
文摘The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July 2020.This unique long-lasting extreme event and its origin have attracted considerable attention.Previous studies have suggested that the Indian Ocean(IO)SST forcing and soil moisture anomaly over the Indochina Peninsula(ICP)were responsible for this unexpected event.However,the relative contributions of IO SST and ICP soil moisture to the 2020 mei-yu rainfall event,especially their linkage with atmospheric circulation changes,remain unclear.By using observations and numerical simulations,this study examines the synergistic impacts of IO SST and ICP soil moisture on the extreme mei-yu in 2020.Results show that the prolonged dry soil moisture led to a warmer surface over the ICP in May under strong IO SST backgrounds.The intensification of the warm condition further magnified the land thermal effects,which in turn facilitated the westward extension of the western North Pacific subtropical high(WNPSH)in June‒July.The intensified WNPSH amplified the water vapor convergence and ascending motion over the YRB,thereby contributing to the 2020 mei-yu.In contrast,the land thermal anomalies diminish during normal IO SST backgrounds due to the limited persistence of soil moisture.The roles of IO SST and ICP soil moisture are verified and quantified using the Community Earth System Model.Their synergistic impacts yield a notable 32%increase in YRB precipitation.Our findings provide evidence for the combined influences of IO SST forcing and ICP soil moisture variability on the occurrence of the 2020 super mei-yu.
基金funded by the National Natural Science Foundation of China (U1901217)Guangdong Basic and Applied Basic Research Foundation (2021A1515011298)+1 种基金the National Key R&D Program of China (2021YFF0501202)Special Fund of South China Sea Institute of Oceanology of the Chinese Academy of Sciences (SCSIO2023QY06)。
文摘Mineral carbonation, which precipitates dissolved carbon dioxide(CO_(2)) as carbonate minerals in basaltic groundwater environments, is a potential technique for negative emissions. The Leizhou Peninsula in southwest Guangdong province has extensive basalt, indicating a promising potential for CO_(2) storage through rapid mineralization. However, understanding of the basic geological setting, potential, and mechanisms of CO_(2) mineralization in the basalts of the Leizhou Peninsula is still limited. The mineralization processes associated with CO_(2)storage at two candidate sites in the area are investigated in this paper: Yongshi Farm and Tianyang Basin(of the dried maar lake). Petrography,rock geochemistry, basalt petrophysical properties, and groundwater hydrochemistry analyses are included in the study. Numerical simulation is used to examine the reaction process and its effects. The results show that basalts in the study areas mainly comprise plagioclase, pyroxene, and Fe–Ti oxides, revealing a total volume fraction exceeding 85%. Additionally, small amounts of quartz and fayalite are available, with volume fractions of 5.1% and 1.0%, respectively. The basalts are rich in divalent metal cations, which can form carbonate minerals, with an average of approximately 6.2 moles of metal cations per 1 kg of rock. The groundwater samples have a pH of 7.5–8.2 and are dominated by the Mg–Ca–HCO3 type. The basalts demonstrate a porosity range of 10.9% to 28.8%, with over 70% of interconnected pores. A 20-year geochemical simulation revealed that CO_(2) injection dissolves primary minerals, including anorthite, albite, and diopside, while CO_(2)mineralization dissolves precipitation secondary minerals, such as calcite, siderite, and dolomite. Furthermore, a substantial rise in pH from 7.6to 10.6 is observed in the vicinity of the injected well, accompanied by a slight reduction in porosity from 20% to 19.8%. Additionally, 36.8% of the injected CO_(2) underwent complete mineralization within five years, revealing an increasing percentage of 66.1% if the experimental period is extended to 20 years. The presence of abundant divalent metal cations in basalts and water-bearing permeable rocks in the Leizhou Peninsula supports the potential for mineral carbonation in basalts, as indicated by the geochemical simulation results. Additional research is necessary to identify the factors that influence the CO_(2) mineralization, storage, and sensitivity analysis of basalt in the Leizhou Peninsula.
基金Under the auspices of National Social Science Foundation of China (No.21BJY202)。
文摘There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial carrier.Accurately identifying the differences in spatial characteristics and influencing factors of each type,is essential for creating urban and rural B&B agglomeration areas.This study used density-based spatial clustering of applications with noise(DBSCAN)and the multi-scale geographically weighted regression(MGWR)model to explore similarities and differences in the spatial distribution patterns and influencing factors for urban and rural B&Bs on the Jiaodong Peninsula of China from 2010 to 2022.The results showed that:1)both urban and rural B&Bs in Jiaodong Peninsula went through three stages:a slow start from 2010 to 2015,rapid development from 2015 to 2019,and hindered development from 2019 to 2022.However,urban B&Bs demonstrated a higher development speed and agglomeration intensity,leading to an increasingly evident trend of uneven development between the two sectors.2)The clustering scale of both urban and rural B&Bs continued to expand in terms of quantity and volume.Urban B&B clusters characterized by a limited number,but a higher likelihood of transitioning from low-level to high-level clusters.While the number of rural B&B clusters steadily increased over time,their clustering scale was comparatively lower than that of urban B&Bs,and they lacked the presence of high-level clustering.3)In terms of development direction,urban B&B clusters exhibited a relatively stable pattern and evolved into high-level clustering centers within the main urban areas.Conversely,rural B&Bs exhibited a more pronounced spatial diffusion effect,with clusters showing a trend of multi-center development along the coastline.4)Transport emerged as a common influencing factor for both urban and rural B&Bs,with the density of road network having the strongest explanatory power for their spatial distribution.In terms of differences,population agglomeration had a positive impact on the distribution of urban B&Bs and a negative effect on the distribution of rural B&Bs.Rural B&Bs clustering was more influenced by tourism resources compared with urban B&Bs,but increasing tourist stay duration remains an urgent issue to be addressed.The findings of this study could provide a more precise basis for government planning and management of urban and rural B&B agglomeration areas.
基金supported by the Talent Research Project of Hebei Province(No.HBQZYCXY010)the National Natural Science Foundation of China-Shandong Joint Fund Program entitled“Control Mechanisms of Faults on Deep Gold Deposits in Jiaodong Peninsula”(No.U2006201)+1 种基金Isotopic analyses at the University of Alberta were supported by an NSERC discovery grant to D.G.Pearsonsupported by the National Natural Science Foundation of China(No.42103024)China Postdoctoral Science Foundation(Nos.2020T130618 and 2020M682516).
文摘The Mesozoic intrusions of the Jiaodong Peninsula,eastern China,host giant gold deposits.Understanding the genesis of these deposits requires the determination of the source of the parental auriferous fluid and the timing of gold mineralization,which are strongly influenced by the cooling/uplift histories of the hosting intrusions.We performed an integrated U-Pb geochronology study on both zircon and apatite from four major magmatic episodes of the Jiaodong Peninsula.The zircon and apatite U-Pb ages are 156.9±1.2 and 137.2±2.4 Ma for the Linglong intrusion,129.9±1.0 and 125.0±3.8 Ma for the Qujia intrusion,119.5±0.7 and 117.2±1.8 Ma for the Liulinzhuang intrusion,118.6±1.0 and 111.6±1.6 Ma for the Nansu intrusion,respectively.The coupled zircon and apatite data of these granitoids indicate a slow cooling rate(11.9°C/Ma)in the Late Jurassic,and rapid uplift and cooling(35.8-29.2°C/Ma)in the Early Cretaceous.The dramatically increased uplift and cooling period in the Early Cretaceous are contemporaneous with large-scale gold mineralization in the Jiaodong Peninsula.This implies that thermal upwelling of asthenosphere and related tectonic extension played an important role in gold remobilization and precipitation.
文摘The 2024 Noto Peninsula Earthquake was a significant seismic event that caused extensive damage across the region, characterized by a strong shake, subsequent tsunami, fires, liquefaction, and landslides. An emergency survey was conducted by our team from January 6 to January 8, 2024, focusing primarily on the impact of the earthquake on road bridges. This preliminary report includes ground motion records from the most affected areas and their response spectra, providing insights into the earthquake's intensity and characteristics. Among the key findings, substantial damage was reported to the long-span bridges connecting Noto Island to the mainland,specifically the Noto Island Ohashi Bridge and the Naka-Noto Agriculture Bridge(Twin Bridge Noto). These bridges are crucial as they serve as the sole access points to Noto Island. Additionally, the survey recorded damage to several other structures, including the Okogawa Bridges, Ouchigata Bridge, and a collapsed old wooden bridge.
文摘This study presents various approaches to calculating the bearing capacity of spread footings applied to the rock mass of the western corniche at the tip of the Dakar peninsula. The bearing capacity was estimated using empirical, analytical and numerical approaches based on the parameters of the rock mass and the foundation. Laboratory tests were carried out on basanite, as well as on the other facies detected. The results of these studies give a range of allowable bearing capacity values varying between 1.92 and 11.39 MPa for the empirical methods and from 7.13 to 25.50 MPa for the analytical methods. A wide dispersion of results was observed according to the different approaches. This dispersion of results is explained by the use of different rock parameters depending on the method used. The allowable bearing capacity results obtained with varying approaches of calculation remain admissible to support the loads. On the other hand, the foundation calculations show acceptable settlement of the order of a millimeter for all the layers, especially in the thin clay layers resting on the bedrock at shallow depths, where the rigidity of the rock reduces settlement.
文摘In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the Arabian Peninsula from January 1986 to August 2015. The mean monthly variations of the temperatures at these levels are characterised and established. The magnitudes of the annual trends of the mean temperatures for each site for the selected barometric levels are studied and statistically tested using Mann-Kendall rank statistics at different significance levels. The temperature trends at different pressure levels show that the upper troposphere and lower stratosphere are warming, while the middle troposphere is cooling which is consistent with the findings of other studies. The variations in upper air temperature observed in this study can be attributed to a range of factors, including increasing greenhouse gas concentrations, changes in atmospheric circulation patterns, variations in solar activity, aerosols and volcanic eruptions, and land use and land cover change.
文摘Leizhou Peninsula, located at southem end of mailand China, has 9 284.3 ha mangrove distributed more than 100 sites along its inlets and open coastlines. This paper presents the surveys on mangrove area in Leizhou Peninsula during 2000 and 2008, especially the survey in the eight major mangrove areas in 2002. The flora recorded in mangrove systems includes 69 large algea species, 13 native true mangrove species, nine native semi-mangrove species, and another seven intoduced true mangrove species with Sonneratia apetala as the quickest growing exotic mangrove species dominatant in the mangrove plantations, and more than 100 land flora species, consisting of 17 main mangrove associations. The plant biodiversity habitats remained mainly small patches and diverse, and were becoming worse under the intensive disturbance of human acitivities and coastal pollutions, which decreased the value of mangrove coasts as the important sites for flying-by migrating birds in Leizhou Peninsula. The effective mangrove conservation measures should be implemented.
基金The paper was supported by the project of integrated mangrove management and coastal protection(IMMCP) in Leizhou Peninsula Guangdong Province.
文摘The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage. By setting plot and selecting standard tree, investigation and measurement on height growth, diameter growth, biomass, productivity, and so on, were made in a S. apetala plantation at age of six at Lanbei, Fucheng, Leizhou Peninsula in May 2001. The investigating results showed that the mean annual height growth of plantation was 2.03 m and mean annual growth of diameter at breast height (DBH) was 2.35 cm. There exists a significant correlation between the diameter at ground surface (DGS) and DBH. The average biomass of a single standard tree in dry weight was 95.647 kg/m2. A ratio of above-ground biomass to under-ground biomass was 1.60. The stand biomass of unit area was 22.955 kg/m2, singletree wood volume was 88.23 dm3, and the annual wood volume productivity (PA) of the same year was 0.407. The forest energy accumulation was 424.851 MJ/m2, with annual solar energy fixing rate of 40.68 ×10-7%. It is concluded that S. apetala species had characteristics of outstanding high biomass accumulation and could be used as coastal planting tree species in southern China.
基金Supported by National Natural Science Foundation of China (40901027,No. 41106036)Shandong Natural Science Foundation (2011DQ006)the International Partnership Creative Group, the Chinese Academy of Sciences "Typical Environmental Process and Effects of Coastal Zone Resources"~~
文摘[Objective] The aim was to study the effects of urbanization and industrialization on farmland system in Shandong Peninsula. [Method] In Shandong Peninsula, the effects were studied and analyzed using remote sensing and image interpretation with spatial data analysis and statistic data analysis. [Result] During researching periods in Shandong Peninsula, wasteland area changed from decreasing to increasing; farmland area was declining; orchard and forestry areas were increasing, mainly resulting from political policies and benefits maximization of farmers. Meanwhile, chemical fertilizers and agricultural mechanization are more frequently applied with industrialization and urbanization, leading significant effects on environment, industry and urban. [Conclusion] More policies should be formulated to promote harmonious development of society, economy and environment.
基金supported by the Korea Polar Research Institute(PE19030)for Y.I.Leethe Polar Academic Program(PE19900),KOPRI for H.S.Lim.
文摘The provenance of modern beach sands from the Barton and Weaver peninsulas of King George Island,South Shetland Islands,West Antarctica was investigated based on their modal composition and geochemical data.The source rocks and provenance tectonic setting are interpreted as volcanic and plutonic rocks formed in the magmatic arc setting.This interpretation is generally consistent with the currently distributed bedrocks in the ice-free areas and tectonic setting of King George Island.However,the composition of beach sands of the Barton and Weaver peninsulas is different from distribution of bedrocks exposed in the ice-free areas of both peninsulas.The present beach sands are interpreted as previous subaqueous moraines that were eroded and transported by advancing glaciers across the both peninsulas and deposited in front of the glacier grounding line.In other words,sand sediments in the beaches of the two peninsulas were not derived from bedrocks currently exposed in ice-free areas,but it is interpreted that they were subaqueous moraines before deglaciation and were mixed with sediment derived from wave erosion of bedrocks and sediments of the paleoshoreline during the isostatic uplift of King George Island.Finally,they were reworked under the current beach environments.
基金supported jointly by the Fostering Plan Fund for Trans-century Excellent Talents and the Key Project of Science and Technology Research of the Ministry of Education(No.03178)the National Natural Science Foundation of China(No.40572063 and No.40234051).
文摘For understanding the possible deep-seated processes and geodynamic constrains on gold mineralization, comprehensive physicochemical and geochemical studies of gold mineralization have been undertaken within the paleo-lithosphere framework during the metailogenic epoch from the northwestern part of the Jiaodong Peninsula in this paper. A general image of the paleo-crust has been remained although it has been superimposed and reformed by post-metailogenic tectonic movements. The gold ore deposits occur usually in local uplifts and gradient belts featuring a turn from steep to gentle in granite-metamorphic contact zones, relative uplifts of gradient zones of the Curier isothermal interfaces, depressions of the Moho discontinuity and areas where depth contours are cut by isotherms perpendicularly. Gold mineralization and lithogenesis are characterized by high temperature, low pressure and high strength of thermal flux. The depth of mineralization ranges from 0.8 to 4.5 km. The depth of the top interface of the granitic complex in the metallogenic epoch is about 3 km. There is a low-velocity layer (LVL) at the bottom of the upper crust with a depth close to 19.5 km, which may be a detachment belt in the crust. The appearance of the LVL indicates the existence of paleo-hyperthermal fluid or relics of molten magma chambers, which reflects partial melting within the crust during the diagenetic and metallogenic epochs and the superposition effects of strike-slip shearing of the Taulu fault zone. The subsidence of the Moho is probably attributed to the coupling process of the NW-SE continental collision between North China and the Yangtze Block and the strike-slip movement of the Tanlu fault accompanied with underplating of mantle magma in the northwestern part of the Jiaodong Peninsula. The underplating of mantle magma may result in partial melting and make granite magma transfer upwards. This is favorable for the migration of metallogenic materials from deep to shallow to be enriched to form deposits. Coupling interactions between the strike-slip of the Taulu fault, the underplating of mantle magma, partial melting within the crust, and hyperthermal fluid, etc. may be the important factors controlling the gold mineralization and spatial structures in the metailogenic system.
基金Major Program of National Natural Science Foundation of China,No.41590840,No.41590842.
文摘Land-use efficiency is low for the urban agglomeration of China. High-speed transportation construction has been an important factor driving land use change. It is critically important to explore the spatial relationship between the high-speed transportation superiority degree and land-use efficiency. We built a model to evaluate the benefits of convenient high-speed transportation using the relative density of highways and the distance from high-speed rail stations and airports as a metric. We used 42 counties of the Shandong Peninsula urban agglomeration as an example. Land-use efficiency was calculated by a DEA model with capital, labor, economic benefits and environmental benefits as input and output factors. We examined the spatial relationships between high-speed transport superiority degree and land-use efficiency and obtained the following results. First, there are significant spatial differences in the relationships between the high-speed transportation superiority degree and land-use efficiency. Taking the two major cities of Jinan and Qingdao as the hubs, the core surrounding counties show significant spatial relationship between land-use efficiency and the high-speed transportation superiority degree. Spatial correlation declines as the distance from the hubs increases. Land-use efficiency is less than high-speed transportation convenience in areas along the transportation trunks that are distant from the hub cities. Correlation is low in areas that are away from both hub cities and transportation trunk routes. Second, high-speed transportation has a positive relationship with land-use efficiency due to the mechanism of element agglomeration exogenous growth. Third, high-speed transportation facilitates the flow of goods, services and technologies between core cities and peripheral cities as space spillover(the hub effect). This alters the spatial pattern of regional land-use efficiency. Finally, the short-board effect caused by decreased high-speed transport construction can be balanced by highway construction and the proper node layouts of high-speed rail stations and airports, resulting in a well-balanced spatial pattern of land-use efficiency.