High-dimensional data(a dataset with many features)were collected from 64 sampling sites to analyze the water quality in estuaries along the coast of the Bohai Sea,North China.The twenty-five water quality parameters ...High-dimensional data(a dataset with many features)were collected from 64 sampling sites to analyze the water quality in estuaries along the coast of the Bohai Sea,North China.The twenty-five water quality parameters analyzed were collected monthly from January 2021 to December 2021.Multivariate statistical techniques,such as the absolute principal component score-multiple linear regression model(APCS-MLR),correlation analysis,and analysis of variance were used to identify and quantify the potential sources or factors affecting water quality and to analyze the spatial-temporal variation in water quality.The water quality indices(WQIs),ranging from 67.96 to 70.67,showed that the water quality was at an intermediate level in the estuaries during both the flood and nonflood seasons.The concentrations of total phosphorus(TP),ammonia N(AN),and organic pollutants were greater in the Haihe River Basin than in the Liaohe River and Huanghe-Huaihe River Basins.The concentration of total nitrogen(TN)in the Haihe River Basin was lower than that in the Liaohe River and Huanghe-Huaihe River Basins.Heavy metal concentrations in the Liaohe River Basin were greater than those in the Haihe River and Huanghe-Huaihe River Basins.The annual mean concentrations of AN in the estuaries of the Haihe,Liaohe,and Huanghe(Yellow)rivers exhibited significant decreasing trends from 2013 to 2022,but no significant decreasing trends were found for permanganate index(COD_(Mn))or the TP.The concentrations of TN and AN were lower in the flood season than in the nonflood season,and the TP concentration was greater in the flood season than in the nonflood season.However,the concentrations of organic pollutants did not exhibit significant differences.Domestic sewage and industrial wastewater,substance exchange between air and water,nonpoint sources from rural and urban areas,and aquaculture wastewater were the major sources or factors responsible for water pollution in the estuaries.展开更多
Guided by the fundamental principles of the whole petroleum system,the control of tectonism,sedimentation,and diagenesis on hydrocarbon accumulation in a rifted basin is studied using the data of petroleum geology and...Guided by the fundamental principles of the whole petroleum system,the control of tectonism,sedimentation,and diagenesis on hydrocarbon accumulation in a rifted basin is studied using the data of petroleum geology and exploration of the second member of the Paleogene Kongdian Formation(Kong-2 Member)in the Cangdong Sag,Bohai Bay Basin,China.It is clarified that the circle structure and circle effects are the marked features of a continental fault petroliferous basin,and they govern the orderly distribution of conventional and unconventional hydrocarbons in the whole petroleum systems of the rifted basin.Tectonic circle zones control sedimentary circle zones,while sedimentary circle zones and diagenetic circle zones control the spatial distribution of favorable reservoirs,thereby determining the orderly distribution of hydrocarbon accumulations in various circles.A model for the integrated,systematic accumulation of conventional and unconventional hydrocarbons under a multi-circle structure of the whole petroleum system of continental rifted basin has been developed.It reveals that each sag of the rifted basin is an independent whole petroleum system and circle system,which encompasses multiple orderly circles of conventional and unconventional hydrocarbons controlled by the same source kitchen.From the outer circle to the middle circle and then to the inner circle,there is an orderly transition from structural and stratigraphic reservoirs,to lithological and structural-lithological reservoirs,and finally to tight oil/gas and shale oil/gas enrichment zones.The significant feature of the whole petroleum system is the orderly control of hydrocarbons by multi-circle stratigraphic coupling,with the integrated,orderly distribution of conventional and unconventional reserves being the inevitable result of the multi-layered interaction within the whole petroleum system.This concept of multi-circle stratigraphic coupling for the orderly,integrated accumulation of conventional and unconventional hydrocarbons has guided significant breakthroughs in the overall,three-dimensional exploration and shale oil exploration in the Cangdong Sag.展开更多
Fog is a highly complex weather phenomenon influenced by numerous factors.This study investigated the impact of the Changbai Mountains’topography on the formation and development of spring fog in the Bohai Sea.From 1...Fog is a highly complex weather phenomenon influenced by numerous factors.This study investigated the impact of the Changbai Mountains’topography on the formation and development of spring fog in the Bohai Sea.From 12 to 14 May 2021,the Bohai region experienced a sea fog event.Utilizing Himawari-8 satellite data,ERA5 reanalysis dataset,land and sea station observations,the WRF model,a topography sensitivity experiment,and backward trajectory tracking,the influence of the Changbai Mountains’topography on the evolution of this sea fog event was assessed.Results indicated that the Changbai Mountains’topography significantly impacted the propagation and concentration of the sea fog through dual effects—namely,the Venturi Effect and Foehn Clearance Effect.Comparative simulations incorporating and excluding the Changbai Mountains revealed that its topography favored weak convergence(Venturi Effect)of low-level airflow over the Bohai Sea induced by a high-pressure system,promoting westward fog expansion.Additionally,the backward trajectory analysis further indicated that the Foehn Clearance Effect of the Changbai Mountains extended its influence far beyond the immediate lee side,contributing to significant changes in atmospheric conditions such as reductions in relative humidity and increases in potential temperature.The dry,warm foehn contributed to a reduction in the liquid water content,ultimately leading to the weakening or even dissipation of the sea fog in the region close to the Changbai Mountains.This study emphasizes the crucial role of the Changbai Mountains’topography in the development and evolution of fog,providing valuable insights for forecasting fog in regions with complex terrain.展开更多
Ctenophore Pleurobrachia globosa(P.globosa)invades even the northernmost Bohai Sea from the south of China.Three years(2019-2021)of surveys were conducted in the Bohai Bay(BoB)of the Bohai Sea to examine its populatio...Ctenophore Pleurobrachia globosa(P.globosa)invades even the northernmost Bohai Sea from the south of China.Three years(2019-2021)of surveys were conducted in the Bohai Bay(BoB)of the Bohai Sea to examine its population dynamics and potential impact on nuclear power plants.Results show that P.globosa mainly occurred from July to October each year,reaching the maximum abundance in August/September and even bloomed in August 2020.Correlations with environmental factors indicate this species has strong tolerance to acidification and hypoxia,and it has potentially indirect feeding relationship with phytoplankton.Seven stages in three groups were illustrated in life history of P.globosa.Two entire generations were detected in August,confirming its 2-week generation time.Spawning time started earlier in the south than in the north of BoB.The spatiotemporal variation and life cycle of P.globosa in BoB are useful for further study on the invasion,bloom,aggregation,and regeneration of P.globosa.展开更多
Facing the severe decline in beef cattle market prices and leveraging its status as a major cattle-raising city,Binzhou City has actively utilized the superior genetic resources of Bohai Black Cattle.The city has prog...Facing the severe decline in beef cattle market prices and leveraging its status as a major cattle-raising city,Binzhou City has actively utilized the superior genetic resources of Bohai Black Cattle.The city has progressively transitioned from small-scale cattle farming to specialized and large-scale breeding communities by collaborating with experts from national and provincial industrial technology systems including the Chinese Academy of Agricultural Sciences,Shandong Academy of Agricultural Sciences,and Shandong Agricultural University.The breeding focus has shifted from Simmental crossbred cattle to purebred Bohai Black Cattle,hybrid cattle,Angus Cattle,and Hereford Cattle,driving the transformation and upgrading of the beef cattle industry.Emphasizing"germplasm source security",Binzhou has capitalized on the unique advantages of Bohai Black Cattle to achieve doubling in quantity,quality,and profitability of high-grade beef cattle breeds.This initiative supports ecological conservation and high-quality development in the Yellow River Basin.A Qilu Model will be established for national modern animal husbandry,further strengthening Shandong's first beef market.展开更多
The Mesozoic volcanic rocks of the Bodong Low Uplift in the Bohai Bay Basin have been studied and explored for years.In 2024,the LK7-A well drilled in this region tested high-yield oil and gas flows from volcanic weat...The Mesozoic volcanic rocks of the Bodong Low Uplift in the Bohai Bay Basin have been studied and explored for years.In 2024,the LK7-A well drilled in this region tested high-yield oil and gas flows from volcanic weathered crust.These volcanic rocks need to be further investigated in terms of distribution patterns,conditions for forming high-quality reservoirs,and main factors controlling hydrocarbon accumulation.Based on the logging,geochemical and mineralogical data from wells newly drilled to the Mesozoic volcanic rocks in the basin,and high-resolution 3D seismic data,a comprehensive study was conducted for this area.The research findings are as follows.First,the volcanic rocks in the LK7-A structure are adakites with a large source area depth,and the deep and large faults have provided channels for the emplacement of intermediate-acidic volcanic rocks.Second,volcanic rock reservoirs are mainly distributed in tectonic breccias and intermediate-acidic lavas,and they are dominantly fractured-porous reservoirs,with high-porosity and low-permeability or medium-porosity and low-permeability.Third,the dominant lithologies/lithofacies is the basic condition for forming large-scale volcanic rock reservoirs.Structural fractures and late-stage strong weathering are crucial mechanisms for the formation scale of reservoirs in the Mesozoic volcanic rocks.Fourth,the Bodong Low Uplift exhibits strong hydrocarbon charging by two sags and overpressure mudstone capping,which are favorable for forming high-abundance oil and gas reservoirs.The Mesozoic volcanic buried hills in the study area reflect good trap geometry,providing favorable conditions for large-scale reservoir formation,and also excellent migration and accumulation conditions.Areas with long-term exposure of intermediate-acidic volcanic rocks,particularly in active structural regions,are the key targets for future exploration.展开更多
Marine heat waves(MHWs), characterized by extreme warm sea surface temperature events, frequently occur in Chinese marginal seas. However, the seasonal variation and joint distribution of MHWs in the Bohai Sea have no...Marine heat waves(MHWs), characterized by extreme warm sea surface temperature events, frequently occur in Chinese marginal seas. However, the seasonal variation and joint distribution of MHWs in the Bohai Sea have not been fully described. Therefore, we conducted a systematic investigation of MHWs in this region. Our findings indicate that the frequency of MHW is low during winter, with long duration and weak intensity, while in summer, it is opposite, being high in the frequency, and shorter but stronger. Notably, in summer, the Laizhou and Liaodong bays exhibit a relatively long total day of MHWs compared to other areas in the Bohai Sea. Furthermore, our analysis of the joint distribution of MHWs, considering both duration and intensity, reveals significant seasonal variations. To provide practical insights for marine ranching, we have also investigated time series of MHWs at several specific stations and computed the correlation coefficients between MHW intensity and potential influential factors. Results suggest that sea surface height, cloud cover, wind stress, and wind stress curl are significantly correlated with MHW intensity, although these relationships vary geographically and seasonally. Overall, these findings elucidate the seasonal variation and potential influential factors of MHWs in the Bohai Sea and offer insights for decision-making and planning in marine ranching.展开更多
With the rapid economic development in the surrounding coastal zone, more and more wastewater has been discharged into the Bohai Bay. And with the scale of coastal exploitation being expanded year by year, the eco-env...With the rapid economic development in the surrounding coastal zone, more and more wastewater has been discharged into the Bohai Bay. And with the scale of coastal exploitation being expanded year by year, the eco-environment of the Bohai Bay has been confronted with great pressure. In this paper, the main problems in the eco-environment of the Bohai Bay were summarized firstly. Red tides occurred more frequently and more seriously; salinity rose in inshore area, the fishery resources degenerated; all the above indicate that the eco-environment of the Bohai Bay is under a severe situation Next, to make a concrete study of the existing status of the Bohai Bay, the eco-environment index system was set up. Then the principal components analytic method and grey relation method were adopted to carry on a comprehensive analysis on the status. The results show that serious pollution of inorganic nitrogen and active phosphate, and poor species diversity are the main presentations of the bad quality of the inshore aquatic eco-environment of the Bohai Bay, which is mainly induced by the massive discharge of pollutant from land and the overexploitation in the surrounding coastal zone. At last, the variations of hydrodynamic characteristics and the pollutant transport caused by coastal exploitations such as reclamation and seawater desalination are analyzed. The results show that reclamation in coastal water not only decreases the tidal prism and weakens the tidal current action, but also influences the pollution distribution in the coastal water. The seawater desalination project would cause tremendous influence to the aquatic eco-environment of the Bohai Bay as the pollutant＇s pulse impact. Much more attention would be paid to the reasonable use of the coastal zone resources and the control of pollution from land-based sources.展开更多
In order to reasonably simulate tidal currents around small structures such as piles in a large-scale model domain, a 2-D hydrodynamic integrated model for Bohai Sea is established with the finite element method. The ...In order to reasonably simulate tidal currents around small structures such as piles in a large-scale model domain, a 2-D hydrodynamic integrated model for Bohai Sea is established with the finite element method. The grid can be discretionarily refined as a non-structure triangle or quadrilateral so that piers can be treated as one or several impermeable elements with an area of 20 to 30 km^2 in a model domain over 85 700 km^2. The computational results of tidal levels and horizontal velocities are in good agreement with the field data. Based on the computed results by the model, the layout of an open 105 DWT liquefied natural gas （LNG）terminal in Caofeidian, Bohal Sea is effectively and reasonably optimized. It can be concluded that the model is suitable and reasonable for direct simulation of tidal currents around small structures in projects.展开更多
Selecting suspension sample 51 stations in Bohai Bay contents of heavy metals(Fe, Mn, Si, Ba) analysis, studied the distribution of the suspension of heavy metals. It Showed that in the study area, the content of iron...Selecting suspension sample 51 stations in Bohai Bay contents of heavy metals(Fe, Mn, Si, Ba) analysis, studied the distribution of the suspension of heavy metals. It Showed that in the study area, the content of iron was the highest, silicon content was lowest; in descending order: Fe>Mn>Ba>Si; the coefficient of variation is between 7.60 and 110.35; except barium greater the degree of dispersion(coefficient of variation is greater than 100).With the samples of stations, the 4 kinds of heavy metals are from low to high, from the south to the north. Silicon content was the highest in 51 stations. The other 3 elements appeared in 50 stations.展开更多
By using drilling,high-precision 3 D seismic data,data of geochemistry,logging and testing,the reservoir characteristics and accumulation conditions of the KL6-1 lithologic oilfield in the Laibei Low Uplift in the Boh...By using drilling,high-precision 3 D seismic data,data of geochemistry,logging and testing,the reservoir characteristics and accumulation conditions of the KL6-1 lithologic oilfield in the Laibei Low Uplift in the Bohai Sea are examined comprehensively.The study shows that:KL6-1 oilfield is a monolithic,high-quality,large-scale Neogene lithologic oilfield featuring shallow reservoir depth,high productivity,concentrated oil-bearing intervals,large oil-bearing area,and high reserve abundance;hydrocarbon source supply from two directions provides a sufficient material basis for the formation of large oil field;two types of"inherited structural ridge"developed under the effect of block rotation,late active faults formed by Neotectonic movement,and widely distributed contiguous sand bodies provide an efficient oil and gas transportation system for the large-scale accumulation of oil and gas;contiguous channel and lacustrine lowstand system sand bodies developed in low accommodation condition provide the basic condition for the formation of large-scale lithologic traps;deep formations structural ridge,faults(dominant migration pathways)and large-scale superimposed contiguous sand bodies constitute a"vine type"oil and gas migration and accumulation system in the Laibei Low Uplift,which is conducive to the formation of large-scale and high-abundance lithologic reservoir in this area.The successful discovery of KL6-1,100 million ton reserve order lithologic oil field,has revealed the exploration potential of Neogene large lithologic reservoirs in Bohai Sea,expanded the exploration field,and also has certain reference significance for the exploration of large lithologic reservoirs in similar areas.展开更多
[Objetive] To make clear the regional agricultural development level.[Method] To accelerate the process of modern agricultural development of Bohai Rim,the assessment index system of modern agriculture was established...[Objetive] To make clear the regional agricultural development level.[Method] To accelerate the process of modern agricultural development of Bohai Rim,the assessment index system of modern agriculture was established preliminarily and the data of provinces and cities in Bohai Rim was evaluated and analyzed,regarding the comprehensive development level of modern agriculture as general target and the input level of modern agriculture,the output level of modern agriculture,the social development level of countryside and the sustainable development level of agriculture as grading index.[Result] The results showed that Bohai Rim just entered the developmental stage of modern agriculture,with the integrated index of 0.585.Viewed from regional perspective,Beijing topped the others with the index of 0.798,which was followed by 0.694 of Tianjin,0.644 of Shandong,0.606 of Liaoning and Hebei province had the lowest value of 0.595.[Conclusion] Among all cities in this region,none of them reached at the developed level of modern agriculture.There were ten cities,which were mainly located in Shandong Province,were at the primary stage while the most of others were at the preliminary or initial stage.展开更多
Based on the data from 3D seismic surveys,drilling,sidewall coring,thin sections,and tests,this paper analyzes Meso-Cenozoic geotectonic dynamics,buried-hill reservoir characteristics,and differential enrichment patte...Based on the data from 3D seismic surveys,drilling,sidewall coring,thin sections,and tests,this paper analyzes Meso-Cenozoic geotectonic dynamics,buried-hill reservoir characteristics,and differential enrichment patterns of oil and gas in the buried hills,as well as case studies of typical reservoirs,to systematically discuss the conditions required for the formation of buried-hills and reservoirs and accumulations in the large oil and gas fields in deep to ultra-deep composite buried hills in the Bohai Sea..The key findings are as follows.First,deep to ultra-deep composite buried hills developed in the offshore Bohai Bay Basin primarily due to the double-episode destruction of the North China Craton in the Yanshanian and Himalayan.The Tanlu Fault's activity and the destruction of the North China Craton worked together to create the destruction center,which moved and converged episodically from the Bohai Bay Basin's margins towards the Bozhong Sag.This led to the formation of two development zones for composite buried hills and an orderly process of mountain-building within the offshore Bohai Bay Basin and subsequently two development zones for composite buried hills,i.e.the middle and inner rim zones within the Bozhong Depression.Second,under the coupling of favorable lithologies and multi-stage structures,the middle and inner rim zones are favorable for the formation of reservoirs in fluid dissolution-pore/fracture zones underlying the weathering crust.Third,Massive hydrocarbons were produced along the middle and inner rim zones during the Episode Ⅱ craton destruction,which caused overpressure.These hydrocarbons then moved to and accumulated in the composite buried hills.Excellent conditions for the accumulation of hydrocarbons are still present in the interior and lower portions of these buried hills.These results encourage a change in buried hill research to investigate composite buried hills in three dimensions.It should be noted that the multi-stage volcanic structures in the inner rim zone of the Sag and the deep to ultra-deep composite buried hill interiors in the middle rim zone are significant successor areas for further Bohai Sea exploration.展开更多
The BZ19-6 deep buried-hill structural belt in the southwest of Bozhong Sag,Bohai Bay Basin,is a newly discovered super-giant oil and gas bearing area.The study on its reservoirs is still in the early stage,and the ch...The BZ19-6 deep buried-hill structural belt in the southwest of Bozhong Sag,Bohai Bay Basin,is a newly discovered super-giant oil and gas bearing area.The study on its reservoirs is still in the early stage,and the characteristics and control factors of reservoir development are not understood deeply.In this paper,cores,sidewall cores,rock sections were analyzed and described.Then,based on regional structural setting,mud logging and logging data,the buried-hill reservoirs in this area were analyzed from the aspects of petrological characteristics,reservoir space types and physical properties,the inherent factors influencing the development of the reservoirs were discussed,and distribution laws of the reservoirs were investigated.And the following research results were obtained.First,the deep buried-hill reservoirs of this belt are a pan-buried hill reservoir system composed of the Palaeocene-Eocene Kongdian Fm glutenite in the upper part and the Archean buried-hill metamorphic granite in the lower part.A multi-layer reservoir structure of glutenite pore zone,weathering crust dissolution fracture zone and inner fracture zone is formed.These reservoirs are complex in genesis and diverse in type.Second,the Archean buried-hill metamorphic granite reservoir can be vertically divided into weathering crust,inner fracture zone and tight zone,and it presents the dual characteristics of porous and fractured media.Third,the buried-hill weathering crust is mainly affected by strong dissolution and leaching superimposed with fracturing,forming fractured-porous reservoir space.The reservoir of inner fracture zone is mainly controlled by the superimposition of three-phrase fractures,which forms the main development period of buried-hill fractures since the Yanshanian.Fourth,the glutenite of Kongdian Fm is a typical sieve deposit and it is mainly controlled by the late dissolution.Fifth,migmatization and supercritical fluid cryptoexplosion play a constructive role in the development of the reservoirs.In conclusion,the understanding of buried-hill glutenite and metamorphic reservoir system developed in this belt is conductive to determining the target and direction of next oil and gas exploration in this area.展开更多
Based on the daily sea surface wind field prediction data of Japan Meteorological Agency(JMA) forecast model,National Centers for Environmental Prediction(NCEP GFS) model and U.S.Navy Operational Global Atmospheric Pr...Based on the daily sea surface wind field prediction data of Japan Meteorological Agency(JMA) forecast model,National Centers for Environmental Prediction(NCEP GFS) model and U.S.Navy Operational Global Atmospheric Prediction System(NOGAPS) model at 12:00 UTC from June 28 to August 10 in 2009,the bias-removed ensemble mean(BRE) was used to do the forecast test on the sea surface wind fields,and the root-mean-square error(RMSE) was used to test and evaluate the forecast results.The results showed that the BRE considerably reduced the RMSEs of 24 and 48 h sea surface wind field forecasts,and the forecast skill was superior to that of the single model forecast.The RMSE decreases in the south of central Bohai Sea and the middle of the Yellow Sea were the most obvious.In addition,the BRE forecast improved evidently the forecast skill of the gale process which occurred during July 13-14 and August 7 in 2009.The forecast accuracy of the wind speed and the gale location was also improved.展开更多
Wave fields in Bohai Sea from 1985 to 2004 were simulated using SWAN wave model by inputting high-resolution hindcast wind fields dataset. Comparisons of wave heights between simulation and observation show good agree...Wave fields in Bohai Sea from 1985 to 2004 were simulated using SWAN wave model by inputting high-resolution hindcast wind fields dataset. Comparisons of wave heights between simulation and observation show good agreement in general. According to the annual extreme values of simulation, this paper gives wave extreme parameters with different return-period for all computation grids in Bohai sea.展开更多
Based on multiple remote-sensing image interpretation and classification, and economic and social data, this study focused on rural settlement and land use change amidst rapid urbanization. Rural settlements, spatial ...Based on multiple remote-sensing image interpretation and classification, and economic and social data, this study focused on rural settlement and land use change amidst rapid urbanization. Rural settlements, spatial and temporal patterns of land use and influ- encing factors in the Bohai Rim were explored within 5x5 km grid cells, as per GIS spatial analysis and geostatistical analysis. Results show that the spatial distribution of rural settle- ments in the Bohai Rim is remarkably varied. The number of rural settlement sites in a 5x5 km grid cell exceeding 5.0 are distributed in a six-area pattern in the Bohai Rim; rural settlement dispersion is particularly high in agricultural regions in south Hebei and southwest Shandong, suggesting rural settlement density keeps increasing from northeast to southwest, charac- terized by high density and dispersed spatial distribution in traditional agricultural regions. Furthermore, rural settlements show dramatic spatial differences in terms of distribution and dynamic change degrees in the Bohai Rim. In terms of spatial distribution, rural residential land is always extensive in plains, with a high density of rural settlements, on the North China Plain in particular, and rural residential land in the south of Shandong province is also exten- sive, with most rural settlement land use areas in the 5x5 km grid cells exceeding 3 km2. However, traditional agricultural regions have underdeveloped economies, industrialization and tertiary industries, characterized by low urbanization rates, with farmers not feeling as- similated in rural or urban areas. In terms of the temporal sequence, urban expansion rapidly promotes the transformation of rural residential lands in rural-urban transitional belts of pro- vincial capital or prefecture-level city into urban lands, and in traditional rural areas, residen- tial lands are growing. The natural environment, transportation conditions, economic devel- opment and farmers＇ incomes all have effects on type of land use change and pattern of rural settlements. It is a core objective for future rural development to reconstruct a rational spatial pattern of villages or towns and well-organized village-town systems, build central villages, key towns or central towns, optimize or reconstruct production, living and eco-space of rural areas. It is of significance for rural geographical research to further interpret and explore spatial reconstruction theory.展开更多
基金Supported by the National Natural Science Foundation of China(No.41571479)。
文摘High-dimensional data(a dataset with many features)were collected from 64 sampling sites to analyze the water quality in estuaries along the coast of the Bohai Sea,North China.The twenty-five water quality parameters analyzed were collected monthly from January 2021 to December 2021.Multivariate statistical techniques,such as the absolute principal component score-multiple linear regression model(APCS-MLR),correlation analysis,and analysis of variance were used to identify and quantify the potential sources or factors affecting water quality and to analyze the spatial-temporal variation in water quality.The water quality indices(WQIs),ranging from 67.96 to 70.67,showed that the water quality was at an intermediate level in the estuaries during both the flood and nonflood seasons.The concentrations of total phosphorus(TP),ammonia N(AN),and organic pollutants were greater in the Haihe River Basin than in the Liaohe River and Huanghe-Huaihe River Basins.The concentration of total nitrogen(TN)in the Haihe River Basin was lower than that in the Liaohe River and Huanghe-Huaihe River Basins.Heavy metal concentrations in the Liaohe River Basin were greater than those in the Haihe River and Huanghe-Huaihe River Basins.The annual mean concentrations of AN in the estuaries of the Haihe,Liaohe,and Huanghe(Yellow)rivers exhibited significant decreasing trends from 2013 to 2022,but no significant decreasing trends were found for permanganate index(COD_(Mn))or the TP.The concentrations of TN and AN were lower in the flood season than in the nonflood season,and the TP concentration was greater in the flood season than in the nonflood season.However,the concentrations of organic pollutants did not exhibit significant differences.Domestic sewage and industrial wastewater,substance exchange between air and water,nonpoint sources from rural and urban areas,and aquaculture wastewater were the major sources or factors responsible for water pollution in the estuaries.
基金Supported by the National Science and Technology Major Project of China(2024ZD1400101)China National Key Research and Development Project(2022YFF0801204)Major Science and Technology Project of CNPC(2023ZZ15YJ01,2021DJ0702)。
文摘Guided by the fundamental principles of the whole petroleum system,the control of tectonism,sedimentation,and diagenesis on hydrocarbon accumulation in a rifted basin is studied using the data of petroleum geology and exploration of the second member of the Paleogene Kongdian Formation(Kong-2 Member)in the Cangdong Sag,Bohai Bay Basin,China.It is clarified that the circle structure and circle effects are the marked features of a continental fault petroliferous basin,and they govern the orderly distribution of conventional and unconventional hydrocarbons in the whole petroleum systems of the rifted basin.Tectonic circle zones control sedimentary circle zones,while sedimentary circle zones and diagenetic circle zones control the spatial distribution of favorable reservoirs,thereby determining the orderly distribution of hydrocarbon accumulations in various circles.A model for the integrated,systematic accumulation of conventional and unconventional hydrocarbons under a multi-circle structure of the whole petroleum system of continental rifted basin has been developed.It reveals that each sag of the rifted basin is an independent whole petroleum system and circle system,which encompasses multiple orderly circles of conventional and unconventional hydrocarbons controlled by the same source kitchen.From the outer circle to the middle circle and then to the inner circle,there is an orderly transition from structural and stratigraphic reservoirs,to lithological and structural-lithological reservoirs,and finally to tight oil/gas and shale oil/gas enrichment zones.The significant feature of the whole petroleum system is the orderly control of hydrocarbons by multi-circle stratigraphic coupling,with the integrated,orderly distribution of conventional and unconventional reserves being the inevitable result of the multi-layered interaction within the whole petroleum system.This concept of multi-circle stratigraphic coupling for the orderly,integrated accumulation of conventional and unconventional hydrocarbons has guided significant breakthroughs in the overall,three-dimensional exploration and shale oil exploration in the Cangdong Sag.
基金jointly supported by the National Natural Science Foundation of China[grant number 42205009]the Open Grants of the State Key Laboratory of Severe Weather[grant number 2024LASWB23]+1 种基金the Collaborative Innovation Project for Marine Meteorological Science and Technology in the Bohai Rim Region[grant number QYXM202315]the Research and Development Project of Hebei Provincial Meteorological Bureau[grant number 22ky26]。
文摘Fog is a highly complex weather phenomenon influenced by numerous factors.This study investigated the impact of the Changbai Mountains’topography on the formation and development of spring fog in the Bohai Sea.From 12 to 14 May 2021,the Bohai region experienced a sea fog event.Utilizing Himawari-8 satellite data,ERA5 reanalysis dataset,land and sea station observations,the WRF model,a topography sensitivity experiment,and backward trajectory tracking,the influence of the Changbai Mountains’topography on the evolution of this sea fog event was assessed.Results indicated that the Changbai Mountains’topography significantly impacted the propagation and concentration of the sea fog through dual effects—namely,the Venturi Effect and Foehn Clearance Effect.Comparative simulations incorporating and excluding the Changbai Mountains revealed that its topography favored weak convergence(Venturi Effect)of low-level airflow over the Bohai Sea induced by a high-pressure system,promoting westward fog expansion.Additionally,the backward trajectory analysis further indicated that the Foehn Clearance Effect of the Changbai Mountains extended its influence far beyond the immediate lee side,contributing to significant changes in atmospheric conditions such as reductions in relative humidity and increases in potential temperature.The dry,warm foehn contributed to a reduction in the liquid water content,ultimately leading to the weakening or even dissipation of the sea fog in the region close to the Changbai Mountains.This study emphasizes the crucial role of the Changbai Mountains’topography in the development and evolution of fog,providing valuable insights for forecasting fog in regions with complex terrain.
基金Supported by the National Key Research and Development Program of China(No.2018 YFC 1407501)the State Key Laboratory of Estuarine and Coastal Zone Environment for Environmental Protection,Chinese Research Academy of Environmental Sciences(No.HKHA 2022004)。
文摘Ctenophore Pleurobrachia globosa(P.globosa)invades even the northernmost Bohai Sea from the south of China.Three years(2019-2021)of surveys were conducted in the Bohai Bay(BoB)of the Bohai Sea to examine its population dynamics and potential impact on nuclear power plants.Results show that P.globosa mainly occurred from July to October each year,reaching the maximum abundance in August/September and even bloomed in August 2020.Correlations with environmental factors indicate this species has strong tolerance to acidification and hypoxia,and it has potentially indirect feeding relationship with phytoplankton.Seven stages in three groups were illustrated in life history of P.globosa.Two entire generations were detected in August,confirming its 2-week generation time.Spawning time started earlier in the south than in the north of BoB.The spatiotemporal variation and life cycle of P.globosa in BoB are useful for further study on the invasion,bloom,aggregation,and regeneration of P.globosa.
基金Supported by Binzhou Comprehensive Experimental Station Project of Pasture Industry Technology System in Shandong Province(SDAIT-23-10).
文摘Facing the severe decline in beef cattle market prices and leveraging its status as a major cattle-raising city,Binzhou City has actively utilized the superior genetic resources of Bohai Black Cattle.The city has progressively transitioned from small-scale cattle farming to specialized and large-scale breeding communities by collaborating with experts from national and provincial industrial technology systems including the Chinese Academy of Agricultural Sciences,Shandong Academy of Agricultural Sciences,and Shandong Agricultural University.The breeding focus has shifted from Simmental crossbred cattle to purebred Bohai Black Cattle,hybrid cattle,Angus Cattle,and Hereford Cattle,driving the transformation and upgrading of the beef cattle industry.Emphasizing"germplasm source security",Binzhou has capitalized on the unique advantages of Bohai Black Cattle to achieve doubling in quantity,quality,and profitability of high-grade beef cattle breeds.This initiative supports ecological conservation and high-quality development in the Yellow River Basin.A Qilu Model will be established for national modern animal husbandry,further strengthening Shandong's first beef market.
基金Supported by the the National Natural Science Foundation of China(U24B2017)。
文摘The Mesozoic volcanic rocks of the Bodong Low Uplift in the Bohai Bay Basin have been studied and explored for years.In 2024,the LK7-A well drilled in this region tested high-yield oil and gas flows from volcanic weathered crust.These volcanic rocks need to be further investigated in terms of distribution patterns,conditions for forming high-quality reservoirs,and main factors controlling hydrocarbon accumulation.Based on the logging,geochemical and mineralogical data from wells newly drilled to the Mesozoic volcanic rocks in the basin,and high-resolution 3D seismic data,a comprehensive study was conducted for this area.The research findings are as follows.First,the volcanic rocks in the LK7-A structure are adakites with a large source area depth,and the deep and large faults have provided channels for the emplacement of intermediate-acidic volcanic rocks.Second,volcanic rock reservoirs are mainly distributed in tectonic breccias and intermediate-acidic lavas,and they are dominantly fractured-porous reservoirs,with high-porosity and low-permeability or medium-porosity and low-permeability.Third,the dominant lithologies/lithofacies is the basic condition for forming large-scale volcanic rock reservoirs.Structural fractures and late-stage strong weathering are crucial mechanisms for the formation scale of reservoirs in the Mesozoic volcanic rocks.Fourth,the Bodong Low Uplift exhibits strong hydrocarbon charging by two sags and overpressure mudstone capping,which are favorable for forming high-abundance oil and gas reservoirs.The Mesozoic volcanic buried hills in the study area reflect good trap geometry,providing favorable conditions for large-scale reservoir formation,and also excellent migration and accumulation conditions.Areas with long-term exposure of intermediate-acidic volcanic rocks,particularly in active structural regions,are the key targets for future exploration.
基金Supported by the National Natural Science Foundation of China (Nos. 92358302, 42227901)。
文摘Marine heat waves(MHWs), characterized by extreme warm sea surface temperature events, frequently occur in Chinese marginal seas. However, the seasonal variation and joint distribution of MHWs in the Bohai Sea have not been fully described. Therefore, we conducted a systematic investigation of MHWs in this region. Our findings indicate that the frequency of MHW is low during winter, with long duration and weak intensity, while in summer, it is opposite, being high in the frequency, and shorter but stronger. Notably, in summer, the Laizhou and Liaodong bays exhibit a relatively long total day of MHWs compared to other areas in the Bohai Sea. Furthermore, our analysis of the joint distribution of MHWs, considering both duration and intensity, reveals significant seasonal variations. To provide practical insights for marine ranching, we have also investigated time series of MHWs at several specific stations and computed the correlation coefficients between MHW intensity and potential influential factors. Results suggest that sea surface height, cloud cover, wind stress, and wind stress curl are significantly correlated with MHW intensity, although these relationships vary geographically and seasonally. Overall, these findings elucidate the seasonal variation and potential influential factors of MHWs in the Bohai Sea and offer insights for decision-making and planning in marine ranching.
基金supported by the National Natural Science Foundation of China(Grant No:50479049)the Support Plan of Science and Technology of Tianjin(Grant No.07ZCGYSH01700)+1 种基金the Natural Science Foundation of Tianjin(Grant No.07JCZDJC10700)Global Environmental Foundation(Grant No.TF053183)
文摘With the rapid economic development in the surrounding coastal zone, more and more wastewater has been discharged into the Bohai Bay. And with the scale of coastal exploitation being expanded year by year, the eco-environment of the Bohai Bay has been confronted with great pressure. In this paper, the main problems in the eco-environment of the Bohai Bay were summarized firstly. Red tides occurred more frequently and more seriously; salinity rose in inshore area, the fishery resources degenerated; all the above indicate that the eco-environment of the Bohai Bay is under a severe situation Next, to make a concrete study of the existing status of the Bohai Bay, the eco-environment index system was set up. Then the principal components analytic method and grey relation method were adopted to carry on a comprehensive analysis on the status. The results show that serious pollution of inorganic nitrogen and active phosphate, and poor species diversity are the main presentations of the bad quality of the inshore aquatic eco-environment of the Bohai Bay, which is mainly induced by the massive discharge of pollutant from land and the overexploitation in the surrounding coastal zone. At last, the variations of hydrodynamic characteristics and the pollutant transport caused by coastal exploitations such as reclamation and seawater desalination are analyzed. The results show that reclamation in coastal water not only decreases the tidal prism and weakens the tidal current action, but also influences the pollution distribution in the coastal water. The seawater desalination project would cause tremendous influence to the aquatic eco-environment of the Bohai Bay as the pollutant＇s pulse impact. Much more attention would be paid to the reasonable use of the coastal zone resources and the control of pollution from land-based sources.
文摘In order to reasonably simulate tidal currents around small structures such as piles in a large-scale model domain, a 2-D hydrodynamic integrated model for Bohai Sea is established with the finite element method. The grid can be discretionarily refined as a non-structure triangle or quadrilateral so that piers can be treated as one or several impermeable elements with an area of 20 to 30 km^2 in a model domain over 85 700 km^2. The computational results of tidal levels and horizontal velocities are in good agreement with the field data. Based on the computed results by the model, the layout of an open 105 DWT liquefied natural gas （LNG）terminal in Caofeidian, Bohal Sea is effectively and reasonably optimized. It can be concluded that the model is suitable and reasonable for direct simulation of tidal currents around small structures in projects.
基金financially supported by Key Laboratory of Marine Oil Spill Identification and Damage Assessment Technology,State Oceanic Administration (201214)Key Laboratory of Pollution Processes and Environmental Criteria (Nankai University),Ministry of Education (KL-PPEC-2013-09)Tianjin aquatic Bureau Youth Fund (J-2014-08)
文摘Selecting suspension sample 51 stations in Bohai Bay contents of heavy metals(Fe, Mn, Si, Ba) analysis, studied the distribution of the suspension of heavy metals. It Showed that in the study area, the content of iron was the highest, silicon content was lowest; in descending order: Fe>Mn>Ba>Si; the coefficient of variation is between 7.60 and 110.35; except barium greater the degree of dispersion(coefficient of variation is greater than 100).With the samples of stations, the 4 kinds of heavy metals are from low to high, from the south to the north. Silicon content was the highest in 51 stations. The other 3 elements appeared in 50 stations.
基金Supported by the China National Science and Technology Major Project(2016ZX05024-003)。
文摘By using drilling,high-precision 3 D seismic data,data of geochemistry,logging and testing,the reservoir characteristics and accumulation conditions of the KL6-1 lithologic oilfield in the Laibei Low Uplift in the Bohai Sea are examined comprehensively.The study shows that:KL6-1 oilfield is a monolithic,high-quality,large-scale Neogene lithologic oilfield featuring shallow reservoir depth,high productivity,concentrated oil-bearing intervals,large oil-bearing area,and high reserve abundance;hydrocarbon source supply from two directions provides a sufficient material basis for the formation of large oil field;two types of"inherited structural ridge"developed under the effect of block rotation,late active faults formed by Neotectonic movement,and widely distributed contiguous sand bodies provide an efficient oil and gas transportation system for the large-scale accumulation of oil and gas;contiguous channel and lacustrine lowstand system sand bodies developed in low accommodation condition provide the basic condition for the formation of large-scale lithologic traps;deep formations structural ridge,faults(dominant migration pathways)and large-scale superimposed contiguous sand bodies constitute a"vine type"oil and gas migration and accumulation system in the Laibei Low Uplift,which is conducive to the formation of large-scale and high-abundance lithologic reservoir in this area.The successful discovery of KL6-1,100 million ton reserve order lithologic oil field,has revealed the exploration potential of Neogene large lithologic reservoirs in Bohai Sea,expanded the exploration field,and also has certain reference significance for the exploration of large lithologic reservoirs in similar areas.
基金Supported by Non-profit project of "Quantitative Evaluation and Adjusting Technology Research on Agricultural Carbon and Nitrogen Balance of Bohai Rim"(200803036)the non-profit project of the twelfth Five-year Plan--"Monitor and Control Research on Agricultural Resource Greenhouse Gas"(201103039)~~
文摘[Objetive] To make clear the regional agricultural development level.[Method] To accelerate the process of modern agricultural development of Bohai Rim,the assessment index system of modern agriculture was established preliminarily and the data of provinces and cities in Bohai Rim was evaluated and analyzed,regarding the comprehensive development level of modern agriculture as general target and the input level of modern agriculture,the output level of modern agriculture,the social development level of countryside and the sustainable development level of agriculture as grading index.[Result] The results showed that Bohai Rim just entered the developmental stage of modern agriculture,with the integrated index of 0.585.Viewed from regional perspective,Beijing topped the others with the index of 0.798,which was followed by 0.694 of Tianjin,0.644 of Shandong,0.606 of Liaoning and Hebei province had the lowest value of 0.595.[Conclusion] Among all cities in this region,none of them reached at the developed level of modern agriculture.There were ten cities,which were mainly located in Shandong Province,were at the primary stage while the most of others were at the preliminary or initial stage.
基金Supported by the China National Offshore Oil Corporation Project(KJGG2022--0302)。
文摘Based on the data from 3D seismic surveys,drilling,sidewall coring,thin sections,and tests,this paper analyzes Meso-Cenozoic geotectonic dynamics,buried-hill reservoir characteristics,and differential enrichment patterns of oil and gas in the buried hills,as well as case studies of typical reservoirs,to systematically discuss the conditions required for the formation of buried-hills and reservoirs and accumulations in the large oil and gas fields in deep to ultra-deep composite buried hills in the Bohai Sea..The key findings are as follows.First,deep to ultra-deep composite buried hills developed in the offshore Bohai Bay Basin primarily due to the double-episode destruction of the North China Craton in the Yanshanian and Himalayan.The Tanlu Fault's activity and the destruction of the North China Craton worked together to create the destruction center,which moved and converged episodically from the Bohai Bay Basin's margins towards the Bozhong Sag.This led to the formation of two development zones for composite buried hills and an orderly process of mountain-building within the offshore Bohai Bay Basin and subsequently two development zones for composite buried hills,i.e.the middle and inner rim zones within the Bozhong Depression.Second,under the coupling of favorable lithologies and multi-stage structures,the middle and inner rim zones are favorable for the formation of reservoirs in fluid dissolution-pore/fracture zones underlying the weathering crust.Third,Massive hydrocarbons were produced along the middle and inner rim zones during the Episode Ⅱ craton destruction,which caused overpressure.These hydrocarbons then moved to and accumulated in the composite buried hills.Excellent conditions for the accumulation of hydrocarbons are still present in the interior and lower portions of these buried hills.These results encourage a change in buried hill research to investigate composite buried hills in three dimensions.It should be noted that the multi-stage volcanic structures in the inner rim zone of the Sag and the deep to ultra-deep composite buried hill interiors in the middle rim zone are significant successor areas for further Bohai Sea exploration.
基金supported by the National Major Science and Technology Project“Comprehensive Study on Buried-Hill Reservoir-Forming in the Bohai Sea and Favorable Exploration Direction”(No.:2016ZX05024-003-010)the Scientific Research Project of CNOOC“Petroleum Geological Characteristics,Forming Mechanism of Typical Oil&Gas Reservoir and Prediction of Prospects of the Buried Hill in the Bohai Sea Area”(No.:CCL2014TJXZSS0870).
文摘The BZ19-6 deep buried-hill structural belt in the southwest of Bozhong Sag,Bohai Bay Basin,is a newly discovered super-giant oil and gas bearing area.The study on its reservoirs is still in the early stage,and the characteristics and control factors of reservoir development are not understood deeply.In this paper,cores,sidewall cores,rock sections were analyzed and described.Then,based on regional structural setting,mud logging and logging data,the buried-hill reservoirs in this area were analyzed from the aspects of petrological characteristics,reservoir space types and physical properties,the inherent factors influencing the development of the reservoirs were discussed,and distribution laws of the reservoirs were investigated.And the following research results were obtained.First,the deep buried-hill reservoirs of this belt are a pan-buried hill reservoir system composed of the Palaeocene-Eocene Kongdian Fm glutenite in the upper part and the Archean buried-hill metamorphic granite in the lower part.A multi-layer reservoir structure of glutenite pore zone,weathering crust dissolution fracture zone and inner fracture zone is formed.These reservoirs are complex in genesis and diverse in type.Second,the Archean buried-hill metamorphic granite reservoir can be vertically divided into weathering crust,inner fracture zone and tight zone,and it presents the dual characteristics of porous and fractured media.Third,the buried-hill weathering crust is mainly affected by strong dissolution and leaching superimposed with fracturing,forming fractured-porous reservoir space.The reservoir of inner fracture zone is mainly controlled by the superimposition of three-phrase fractures,which forms the main development period of buried-hill fractures since the Yanshanian.Fourth,the glutenite of Kongdian Fm is a typical sieve deposit and it is mainly controlled by the late dissolution.Fifth,migmatization and supercritical fluid cryptoexplosion play a constructive role in the development of the reservoirs.In conclusion,the understanding of buried-hill glutenite and metamorphic reservoir system developed in this belt is conductive to determining the target and direction of next oil and gas exploration in this area.
基金Supported by Chinese Meteorological Administration's Special Funds(Meteorology) for Scientific Research on Public Causes( GYHY200906007)Gale Forecast Item of the Shengli Oil Field Observatory (2008001)~~
文摘Based on the daily sea surface wind field prediction data of Japan Meteorological Agency(JMA) forecast model,National Centers for Environmental Prediction(NCEP GFS) model and U.S.Navy Operational Global Atmospheric Prediction System(NOGAPS) model at 12:00 UTC from June 28 to August 10 in 2009,the bias-removed ensemble mean(BRE) was used to do the forecast test on the sea surface wind fields,and the root-mean-square error(RMSE) was used to test and evaluate the forecast results.The results showed that the BRE considerably reduced the RMSEs of 24 and 48 h sea surface wind field forecasts,and the forecast skill was superior to that of the single model forecast.The RMSE decreases in the south of central Bohai Sea and the middle of the Yellow Sea were the most obvious.In addition,the BRE forecast improved evidently the forecast skill of the gale process which occurred during July 13-14 and August 7 in 2009.The forecast accuracy of the wind speed and the gale location was also improved.
基金supported by National Nature Science Foundation of China, China National Basic Research Program (Grant No. 2009CB421201)
文摘Wave fields in Bohai Sea from 1985 to 2004 were simulated using SWAN wave model by inputting high-resolution hindcast wind fields dataset. Comparisons of wave heights between simulation and observation show good agreement in general. According to the annual extreme values of simulation, this paper gives wave extreme parameters with different return-period for all computation grids in Bohai sea.
基金National Natural Science Foundation of China, No. 41401190 No.41130748 No.41101165
文摘Based on multiple remote-sensing image interpretation and classification, and economic and social data, this study focused on rural settlement and land use change amidst rapid urbanization. Rural settlements, spatial and temporal patterns of land use and influ- encing factors in the Bohai Rim were explored within 5x5 km grid cells, as per GIS spatial analysis and geostatistical analysis. Results show that the spatial distribution of rural settle- ments in the Bohai Rim is remarkably varied. The number of rural settlement sites in a 5x5 km grid cell exceeding 5.0 are distributed in a six-area pattern in the Bohai Rim; rural settlement dispersion is particularly high in agricultural regions in south Hebei and southwest Shandong, suggesting rural settlement density keeps increasing from northeast to southwest, charac- terized by high density and dispersed spatial distribution in traditional agricultural regions. Furthermore, rural settlements show dramatic spatial differences in terms of distribution and dynamic change degrees in the Bohai Rim. In terms of spatial distribution, rural residential land is always extensive in plains, with a high density of rural settlements, on the North China Plain in particular, and rural residential land in the south of Shandong province is also exten- sive, with most rural settlement land use areas in the 5x5 km grid cells exceeding 3 km2. However, traditional agricultural regions have underdeveloped economies, industrialization and tertiary industries, characterized by low urbanization rates, with farmers not feeling as- similated in rural or urban areas. In terms of the temporal sequence, urban expansion rapidly promotes the transformation of rural residential lands in rural-urban transitional belts of pro- vincial capital or prefecture-level city into urban lands, and in traditional rural areas, residen- tial lands are growing. The natural environment, transportation conditions, economic devel- opment and farmers＇ incomes all have effects on type of land use change and pattern of rural settlements. It is a core objective for future rural development to reconstruct a rational spatial pattern of villages or towns and well-organized village-town systems, build central villages, key towns or central towns, optimize or reconstruct production, living and eco-space of rural areas. It is of significance for rural geographical research to further interpret and explore spatial reconstruction theory.
