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  • Yu LIU, Fengshou ZHANG, Jianqiang SUN, Zhiqiang ZHU, Yu WANG, Zhongkang YANG, Xin ZHANG, Zhilin GUO, Bo ZHANG, Tao CHEN
    Advances in Earth Science. 2022, 37(12): 1286-1298.

    We analyzed the submissions, acceptances, reviews, and grant funding of various projects of National Natural Science Foundation of China in the Environmental Geosciences in 2022 and pointed out the issues with the submission and review processes. We also summarized the main research progresses and outcomes of the funding projects by the Division of Environmental Geosciences completed at the end of 2021.

  • Weidong YANG, Lianbo ZENG, Xiang LI
    Advances in Earth Science. 2023, 38(2): 151-167.

    Carbon neutrality has become a topic of global consensus. To achieve carbon neutrality, it is also important to enhance carbon sequestration and sink capabilities, apart from the development of new energy to minimize carbon emissions. Carbon sinks can be divided into marine and terrestrial types. The marine carbon sink is mainly composed of three parts: the coastal ecological carbon sink mainly formed by the carbon sequestration effect of coastal vegetation and coastal sediment load, and the marine ecological carbon sink mainly formed by dissolution and microbial pumps in the ocean. Both are directly related to monsoon oceanic current conditions, terrestrial organic inputs, coastal geographical conditions, and human activity. The feasibility of an artificial oceanic carbon sink depends on its impact on marine ecology. In terrestrial carbon sinks, vegetation carbon sinks are formed by organic carbon generated by the photosynthesis of terrestrial plants, including forest, grassland, and wetland vegetation. The influencing factors include temperature and precipitation, atmospheric composition, land use and its changes, and natural disturbance effects. Natural geological carbon sinks mostly consist of soil and karst carbon sinks. Soil carbon sinks are affected by regional vegetation, climatic conditions, soil utilization, and other factors. Karst carbon sinks are mainly produced by weathering between carbonate and silicate rocks absorbing atmospheric CO2, which is affected by temperature, precipitation, rock type, hydrological conditions, and human activity. An artificial geological carbon sink was formed because the captured CO2 was injected into the designated area underground for storage. The storage capacity depends on the evaluation of geological characteristics, reservoir conditions, oil distribution, and production. For the future, it is necessary to act decisively in climatic, natural resources, the social economy, and other aspects to fix carbon, enhance carbon sequestration, and achieve carbon neutrality.

  • Xiaogang CHEN, Ling LI, Jinzhou DU
    Advances in Earth Science. 2022, 37(9): 881-898.

    The negative impact of global climate change on resources, ecology, and the environment is becoming increasingly apparent. Hence, reducing the atmospheric carbon dioxide (CO2) concentration has become a global concern. Intertidal wetlands (e.g., mangroves and salt marshes) have strong carbon sink functions that can reduce the CO2 concentration, thus mitigating global climate change. Mangroves and salt marshes are important coastal blue carbon ecosystems characterized by high soil carbon storage. Porewater exchange and associated carbon exchange driven by tides and rainfall in mangroves and salt marshes are challenging issues when estimating the effects of coastal blue carbon sinks. Large amounts of porewater-derived sediment carbon outwellings remain in the ocean and may represent an important carbon sink; however, they are poorly understood, despite being potentially significant components of the salt marsh carbon budget. This review aims to quantify the porewater exchange rate and related carbon fluxes, analyze their driving mechanisms, and reassess the carbon budgets and carbon sink potentials of mangroves and salt marshes. This study promotes understanding the carbon balance and cycle processes associated with mangrove and salt marsh ecosystems, and provides a scientific basis for the construction, protection, and sustainable development of coastal blue carbon sinks in the context of global climate change.

  • Qi FENG, Zongqiang CHANG, Haiyang XI, Yonghong SU, Xiaohu WEN, Meng ZHU, Jutao ZHANG, Chengqi ZHANG
    Advances in Earth Science. 2022, 37(11): 1101-1114.

    The ecologically fragile region in China and Mongolia is among the regions with the largest distribution area, the largest type of fragile ecology, and the most evident ecological vulnerability. The ecological environment condition in the ecologically fragile areas of China and Mongolia restricts the sustainable development of regional ecology and social economy, and is crucial to the ecological security of China and Mongolia. Thus, it is urgently necessary to thoroughly explore the characteristics of ecologically fragile ecosystems in China and Mongolia and their response mechanisms to global changes, which can provide a scientific basis for regional ecological environmental restoration. Based on the carbon and nitrogen cycles of fragile ecosystems affected by global change, this study presents and summarizes the following key research topics: fragile ecosystem carbon and nitrogen cycles and coupling mechanisms, the influence of global change on fragile ecosystems, fragile ecosystem safety threshold identification and risk assessment under the background of global change, and the adaptive management of fragile ecosystems to global change. In view of the national major needs of ecological safety, researches in the following aspects are urgently needed: analyzing the annual, seasonal, and diurnal characteristics of nitrogen turnover pathways, transformation form, and flux in water-soil-gas-biomass systematically to reveal the carbon and nitrogen cycling process, spatio-temporal law, and coupling mechanism of fragile ecosystems and determine the primary mechanism of the carbon and nitrogen sink function in fragile ecosystems. Building a carbon and nitrogen coupling model in fragile ecosystems, quantifying the influence strength of different intensities of climate change on fragile ecosystem safety and the influence of human disturbance on the carbon and nitrogen cycle and its ecological system, assessing the effect of fragile ecological systems on the carbon and nitrogen cycle in the Earth system and its carbon and nitrogen source-sink effect, and proposing management countermeasures and measures of fragile ecosystems to global change.

  • Weiming CHENG, Keyu SONG, Chenghu ZHOU, Guoan TANG
    Advances in Earth Science. 2022, 37(7): 661-679.

    Geo-information Tupu, which is the origin of the geomorphic information spectrum, is introduced and the concept and development of the geomorphic information spectrum are then discussed. From the perspective of specific research, the research types and status of the geomorphic information spectrum are summarized, including the geomorphic morphological characteristic spectrum (such as, surface slope spectrum, section spectrum, two-dimensional pattern spectrum, and topographic texture spectrum) and the geomorphic development spectrum. Combined with the development of remote sensing, computers, artificial intelligence, and other technologies, the prospect of the combination of knowledge graph and information spectrum in future geomorphic research is analyzed, and the research progress and key technologies of geomorphic information spectrum such as geomorphic information extraction, geomorphic information classification, and geomorphic mapping are summarized. The future development of geomorphic information spectrum is prospected using three aspects: constructing a complete geomorphic information spectrum system, improving key technologies of geomorphic information spectrum, and strengthening the refinement and quantitative research of global geomorphic patterns and evolution. This study can provide a reference for the digitization, informatization, and intellectualization of digital geomorphology to serve as the major strategy for the management of national resources and the environment and promote the development of geomorphology.

  • Haodi WANG, Shiyao CHEN, Senliang BAO, Kaijun REN
    Advances in Earth Science. 2022, 37(8): 822-840.

    Marine science is a discipline developed on the basis of continuous observation data accumulation, and major breakthroughs in marine science development history are inseparable from the updating of ocean datasets. The time extension of existing gridded datasets has become the main form of updating ocean data products. This review summarizes the current development of gridded marine environment datasets. First, the historical development of ocean observations is divided into three stages: an initial accumulation period dominated by sparse observations, a rapid growth period guided by international observation programs, and a high-quality development period driven by data assimilation and ocean reanalysis. Starting from the three key elements of temperature, salinity, and ocean current, we focus on the global gridded ocean environment datasets published and updated internationally in recent decades, including six flow field datasets, such as HYCOM and OFES, and ten thermohaline datasets, such as Argo and IAP. Based on previous studies, the sources, characteristic information, advantages, and disadvantages of these datasets are briefly reviewed to provide a reference for marine scientists. Finally, the future development direction and research focus of ocean gridded datasets are discussed.

  • Qingqiang CHEN, Xueyue WANG, Zhenxing YAO, Qinchuan YANG
    Advances in Earth Science. 2022, 37(9): 915-924.

    Clarifying the stability of salt marsh soil organic carbon sinks is of great significance when scientifically evaluating the carbon sink potential of “blue carbon” in coastal zones. The chemical structure and composition of Soil Organic Matter (SOM) are closely related to the stability of soil organic carbon sinks. This study focused on four reclamation areas with different construction times in the eastern part of Chongming Island, China. Solid-state 13C Nuclear Magnetic Resonance (13C NMR) was used to investigate the characteristics of SOM chemical structures in buried salt marsh samples obtained by drilling and topsoil samples acquired from woods around the drilling cores (CM2, CM4, CM5, and CM6). The purpose of this study was to elucidate the variations in the chemical structure of SOM during its turnover. The results showed that the variations in soil organic carbon functional groups from the surface to the deep layers exhibited similar trends for the four reclamation areas, despite different construction times. The alkyl carbon and aromatic carbon proportions showed an increasing trend whereas those of alkoxy carbon and carbonyl carbon showed a decreasing trend from the topsoil samples to the buried soil samples. The alkyl carbon/alkoxy carbon, aromaticity, and hydrophobic carbon/hydrophilic carbon of the buried salt marsh soil samples were greater than those of the topsoil samples in the woods around the drilling cores. The stability of the SOM chemical structure increased with burial depth. From west to east, alkyl carbon/alkoxy carbon, aromaticity, and hydrophobic carbon/hydrophilic carbon were all less than 1 and showed a gradually increasing trend, but aliphatic carbon/aromatic carbon gradually decreased in the topsoil samples in the woods around the drilling cores. The overall decomposition degree of organic matter in topsoil samples from the woods was low and showed a gradually increasing trend from west to east, which meant that SOM stability gradually improved. This was because the planting time for trees gradually became earlier and the development time for topsoil became longer in the woods from west to east. From east to west, the proportions and ratios of organic carbon functional groups in buried salt marsh samples showed that SOM stability increased with reclamation time. In summary, along with soil development, the decomposition degree of salt marsh SOM continued to improve, with an increasing proportion of refractory SOM components and a decreasing proportion of labile SOM components. In addition, SOM stability continued to increase. The changes in the chemical structure and composition of SOM in the reclamation areas, constructed in different years along the Yangtze River estuary, were studied using solid-state 13C NMR and the results improve understanding about the temporal trend and chemical mechanism underlying soil carbon sink stability.

  • Weibin GAO, Yang CHEN, Haoxian WANG
    Advances in Earth Science. 2023, 38(2): 137-150.

    Since the industrial revolution, human activities have emitted large amounts of CO2 into the atmosphere, causing a rapid increase in global surface temperatures. To cope with global warming, it is necessary to apply negative-emission technologies on a large scale. Enhanced silicate Rock Weathering (ERW) is a form of negative-emission technology based on geochemical principles that accelerates the chemical weathering process of silicate rock by adding silicate rock powder to farmland or forests to stabilize atmospheric CO2 over a short time period. China has abundant and widely-distributed basalt reserves and a large amount of unused mine tailings and alkaline silicate wastes. Therefore, there is great potential for the removal of atmospheric CO2 through ERW. The calculation results show that China can remove 0.13~0.80 Gt CO2 through ERW annually, which is conducive to the realization of the “carbon neutrality” goal. However, ERW still faces many problems. Combining the progress of domestic and international research, the main application effects and influencing factors of ERW are summarized, the potential of ERW application in China is analyzed, and the main issues facing ERW application in China are discussed from five aspects: technology, economy, safety, society, and policy. In view of the focus and shortcomings of the current research, the calculation of ERW carbon sequestration, potential hazards of application, and other key concerns and challenges are presented.

  • Yang HU, Ziwei WANG, Hongmao JIANG, Youchao CHEN, Qiao LIU, Baoli DUAN, Xuyang LU
    Advances in Earth Science. 2022, 37(9): 899-914.

    Mountain glacier ecosystems contain diverse habitats, including ice, snow, meltwater, cryoconite, sediment, debris, and soil. These habitats harbor unique biomes that are dominated by cold-tolerant microbes. Mountain glaciers have responded strongly to climate change and have considerably shrunk in size over recent decades. Mountain glacier ecosystem was divided into supraglacial zone, englacial zone, subglacial zone, and proglacial zone, according to the vertical stratifications, horizontal locations, environmental characteristics, and trophic types of colonized microbes. This study reviewed research focused on the physiological characteristics, community composition, and diversity of the microbial community and ecological factors driving their distributions in these four zones. The studies (2010-2022) about the microbial communities in mountain glacier ecosystems that were reviewed mainly investigated the following: isolation and culture of psychrotrophs and psychrophiles; characteristics of microbial community composition and diversity; microbial community assemblage and succession processes; biogeochemical cycles driven by the microbes; and interactions between ecological factors and the microbial community. Most of the studies were conducted in the proglacial and supraglacial zones and mainly focused on the composition and diversity of the bacterial community. In future studies, all zones should be considered as an integrated system to conduct long-term monitoring and investigation of multiple microbial communities in different habitats. They should also focus on microbial interactions and functions. This study improves understanding about the ecological processes mediated by microbes and their ecological roles in extreme environments, both of which have implications for maintaining the stability of glaciers and surrounding ecosystems.

  • Qiang LIU, Yanfei YUAN, Yifan LIU, Mei SHI, Xiao WANG, Xianxiang LUO, Xiaoyun LI, Hao ZHENG, Fengmin LI
    Advances in Earth Science. 2022, 37(10): 1005-1024.

    The remediation and utilization of salt-affected soil through the application of green and sustainable technologies are important for cultivating healthy soil, ensuring global food security, and mitigating global climate change. Biochar has the potential to improve soil health and increase crop yield because of its multiple advantages, such as excellent pore structure, abundant surface functional groups, and high carbon stability. Recent research focusing on the improvement of salt-affected soils via biochar application has garnered increasing interest. However, the effect of biochar on salt-affected soil is extremely complex and diverse, resulting in a lack of critical mechanisms responsible for biochar performance in salt-affected soils. This greatly limits the application of biochar technology for the improvement of salt-affected soils and the industrialization of biochar. Therefore, this review comprehensively analyzed the impact of biochar on the physical, chemical, and biological properties of salt-affected soils. Specific focus areas included the relationship and critical mechanism between biochar properties and salt-affected soils and the deficiencies in areas that need to be strengthened. We emphasize the importance and urgency of comprehensively evaluating the effects of biochar application in the remediation of salt-affected soils from the perspective of soil health. In this study, we aimed to provide a theoretical basis for the application and popularization of biochar, as well as technical assurance for the green development of salt-affected soils.

  • Chunlin HUANG, Jinliang HOU, Weide LI, Juan GU, Ying ZHANG, Weixiao HAN, Weizhen WANG, Xiaohu WEN, Gaofeng ZHU
    Advances in Earth Science. 2023, 38(5): 441-452.

    Data-driven methods with deep learning as their core have been gradually applied in Earth science; however, challenges remain regarding the interpretability of models and physical consistency. With the background of remote sensing big data, combining deep learning and data assimilation methods to develop new techniques for the simulation and prediction of terrestrial water cycle processes has become an important research direction in Earth science. Τhe progress in deep learning in recent years combines improving the quality of observation data of terrestrial water cycle components and reducing the uncertainty of physical models. Furthermore, the key scientific issues regarding data assimilation in terrestrial hydrology based on deep learning fusing remote sensing big data are classified according to the observations, physical models, and system integration: How can the temporal and spatial representativeness of samples be enhanced when deep learning inverts remote sensing products? How can a new physics-guided deep learning method be developed within the framework of data assimilation? How can the predictability of the terrestrial water cycle be improved through the “data-model” dual drive? Relevant research and exploration should help promote the in-depth application of the “data-model” hybrid modeling method in the field of hydrology and improve the simulation and prediction capacity of the terrestrial water cycle process.

  • Penglong WANG, Bao WANG, Bingxin XU, Yueyue HUANG, Feng GAO, Xueyan ZHAO, Chunlin HUANG, Xiaoyu SONG, Liang ZHOU
    Advances in Earth Science. 2022, 37(9): 937-948.

    The vulnerability of mountain ecosystems and community residents makes them a key area for the research and implementation of the United Nations Sustainable Development Goals (SDGs). The sustainable development of underdeveloped mountainous areas is related to the development process and the effectiveness of the United Nations SDGs. Based on the bibliometric method, which focuses on the development goals associated with SDGs related to mountainous areas, the main countries and research produced by scientific institutions associated with the sustainable development of underdeveloped mountainous areas across the globe were analyzed. Five key research areas for sustainable development in underdeveloped mountainous areas: sustainable livelihoods, the health and well-being of residents, water supply and sanitation, ecosystem protection, and climate change and response, which are closely related to SDGs, were selected and research progress and policy measures in each area are described. At the same time, this study investigated ways of improving the evaluation system to promote the systematization of SDGs evaluation in underdeveloped mountainous areas; used big Earth data to remove the data bottleneck associated with SDGs monitoring in underdeveloped mountainous areas; researched the relationship between SDGs to promote their coordinated implementation in underdeveloped mountainous areas; and carried out an SDGs realization path demonstration to help underdeveloped mountainous areas. In terms of the implementation of SDGs policies in developed mountainous areas, this study analyzed the challenges and countermeasures affecting the realization of SDGs in underdeveloped mountainous areas and provides a useful reference for sustainable development research in underdeveloped mountainous areas.

  • Lele SHU, Yan CHANG, Jian WANG, Hao CHEN, Zhaoguo LI, Lin ZHAO, Xianhong MENG
    Advances in Earth Science. 2022, 37(7): 680-691.

    Hydrological models are efficient and economical tools for conducting scientific studies. They are not only useful in validating scientific theories and guiding the deployment of observation networks, but they also play an indispensable role in facilitating decision-making within socioeconomic spheres such disaster prevention and mitigation. Distributed hydrological modelling via numerical methods entail the application of hydrological equations to express the spatial heterogeneity of hydrological parameters at a fine-scale. This fine-scale analysis allows for a detailed characterization of hydrological processes, which is a critical step within the context of developing robust hydrological models. The SHUD model adopts the finite volume method to resolve integrated surface-subsurface hydrological processes. The model uses an irregular triangular network, which can rapidly realize an ultra-high-resolution numerical simulation (i.e., from meters to kilometers). The AutoSHUD automated hydrological simulation system, which consists of the SHUD model, rSHUD tool, and global essential terrestrial data, can facilitate pre- and post-processing of the model and has been applied to several research projects; hence, the validity and applicability of the model have been verified. At present, the exploration, development, and application of distributed hydrological models by numerical methods are limited in our hydrological community, and there is an urgent need for more original research in this field. The global development of new models as well as the validation, promotion, and improvement of existing models is a worthwhile goal.

  • Congying LI, Sifan WU
    Advances in Earth Science. 2022, 37(11): 1127-1140.

    Cretaceous Oceanic Anoxic Events (OAEs) have recorded significant changes in the climatic and paleoceanographic states of the planet and represent major carbon cycle perturbations. In the past two decades, analytical techniques for stable metal isotopes, such as molybdenum, zinc, uranium, chromium, cadmium, and calcium isotopes, have been developed to study OAEs. By systematically summarizing the geochemical characteristics of molybdenum isotopes (δ98Mo), zinc isotopes (δ66Zn), and uranium isotopes (δ238U), and research advances on Cretaceous OAEs, we found that molybdenum isotopes mainly reflect the transformation between sulfide and non-sulfide in the regional marine environment during OAEs. Zinc isotopes can reflect different responses of regional marine environments to different processes, such as primary productivity, continental weathering, and sediment burial/decomposition. Uranium isotopes can be used to estimate the global extent of seafloor euxinia. The coupled global C-P-U cycle model can simulate the response mechanism of the global ocean to different processes, such as the formation of large igneous provinces, continental weathering, and biological activities. However, the cyclic fractionation mechanism of these isotopes in marine systems is still in progress, and most research has only focused on the deposition record of OAE2. In the future, it will be necessary to conduct more systematic research on OAEs.

  • Kai LUO, Jinlong MA
    Advances in Earth Science. 2022, 37(7): 692-708.

    The mineralization process of elution-deposited Rare Earth Element (REE) deposits is closely related to chemical weathering. Elution-deposited REE deposits in South China are an extremely important type of rare resource, with large reserves, a wide distribution, and a high content of Heavy REEs (HREE). In recent years, the migration and enrichment mechanism of earth elements during the chemical weathering process and the ore-forming mechanism of elution-deposited REE deposits has garnered great research interest. This subject has become one of the central issues in geoscience research. Multiple aspects, such as the metallogenic characteristics and processes of elution-deposited REE deposits, structural characteristics of granite weathering crust, distribution characteristics of REEs, occurrence and migration modes of REEs, main factors affecting the migration and enrichment of REEs, and the characteristics of Eu and Ce anomalies are systematically summarized in this paper. The purpose of this study is to comprehensively summarize knowledge centered on the behavior of REEs in the process of supergene weathering, to provide novel directions for future research. Non-traditional stable isotope tracing of chemical weathering is novel and effective; specifically, stable isotope analysis methods for Ce and Nd have been successfully established. Therefore, future research should explore earth elements through the lens of isotopic methods, as this approach could provide important insights for tracing chemical weathering, revealing the mineralization process of REE deposits, and studying environmental evolution.

  • Hu LI, Xiaoduo PAN
    Advances in Earth Science. 2022, 37(10): 1025-1036.

    The Tibetan Plateau, known as the “Asian Water Tower”, is the source of many major rivers in Asia. Its energy and water cycle processes have important impacts on regional and global climate change. Understanding the water vapor transport process and the contribution of water vapor sources is crucial for clarifying the water vapor budget of the plateau. In this study, we analyze the advantages and disadvantages of the research methods used to study the transport and sources of water vapor on the Tibetan Plateau. The classical Euler method was used to study the qualitative features of water vapor transport by calculating the water vapor flux. In addition, Lagrangian trajectory models are essential tools for studying the quantitative characteristics of water vapor transport by simulating the trajectories of humid air parcels. Eulerian tracer methods can be run in parallel with climate models or a posteriori with reanalysis data to track the water vapor transport process. Physical water vapor tracers are powerful tools for studying the water vapor sources of precipitation by measuring stable water isotopes. This study primarily focused on reviewing relevant research on water vapor transport and sources over the Tibetan Plateau and adjacent areas. Based on these studies, the main water vapor channels and characteristics of water vapor transport over the Tibetan Plateau were summarized. The review concluded with a summary of the challenges of current research and a forecast of future research directions.

  • Lu ZHANG, Qianhui LI, Lu MENG, Qiang ZHANG, Hongsheng ZHANG, Qing HE, Tianliang ZHAO
    Advances in Earth Science. 2022, 37(10): 991-1004.

    The atmospheric boundary layer connects the land surface to the atmosphere through the turbulent exchange of heat, momentum, and trace gases. In addition, it plays an important role in the formation and evolution of weather and climate. The characteristics and formation mechanisms of the deep atmospheric boundary layer have been key focus areas in atmospheric boundary layer research. Focusing on extremely arid regions and special geographical locations, the observational facts and influencing factors of the deep atmospheric boundary layer were reviewed and summarized. Furthermore, a physical description of turbulent motion in the development of the deep atmospheric boundary layer was provided. Using the Taklimakan Desert as an example, the effects of the interactions between the deep atmospheric boundary layer and dust stagnation on weather and climate were discussed. In order to provide a roadmap for future research, this study identified and outlined four key scientific problems related to deep atmospheric boundary layer research.

  • Feng NAN, Fei YU, Anqi XU, Yanan DING
    Advances in Earth Science. 2022, 37(11): 1115-1126.

    Mesoscale eddies play an important role in phenomena such as general circulation, momentum budgets, ocean water mass distribution, and water and nutrient transport. Based on the vertical structure of the density and current core, mesoscale eddies are classified into two categories: surface- and subsurface-intensified. The utilization of remote sensing has provided considerable information on surface-intensified eddies. However, little is known about subsurface eddies due to the lack of in-situ observations, although they have been found occasionally in the global ocean. Currently, subsurface eddies are a trending topic within the scientific community. This study reviews the scientific background and research progress on subsurface eddies, with a focus on the northwestern Pacific Ocean. The vertical structure, evolutionary process, and possible formation mechanism of subsurface eddies are summarized based on observational and modelling results. Their influence on marine biogeochemistry, marine sound propagation, and possible important scientific issues are also discussed.

  • Leiming MA, Hong LIN, Hai CHU, Chunguang YIN, Junping ZHANG, Lei CHEN, Haibin WANG, Kang XU, Xuliang FAN
    Advances in Earth Science. 2023, 38(2): 111-124.

    Severe convective weather systems often cause rainstorms, lightning, gales, hail, and other disasters owing to their small spatial scale and rapid and violent development. Accurate forecasting has always been a difficult and bottleneck problem in the international meteorological field, and it is the focus of disaster prevention and mitigation in Shanghai. This research introduces key technologies developed by the Shanghai Meteorological Department in recent years, such as self-adaptive networking observation of strong convection targets, intelligent identification and prediction of strong convection abrupt structural features, machine learning correction of numerical prediction errors, and system integration. Based on this, an intelligent monitoring and early warning system that can simulate the three-dimensional structure and evolution of a strong convective system is established and applied, which has significantly improved the early warning capability fo severe convection in Shanghai. Relevant technical achievements have provided support for major services such as the China International Import Expo (CIIE) and have been promoted for application in urban disaster prevention and mitigation.

  • Xueliang WANG, Hongyuan LI, Rensheng CHEN, Junfeng LIU, Guohua LIU, Chuntan HAN
    Advances in Earth Science. 2022, 37(7): 726-741.

    A systematic analysis of runoff changes in the Yellow River is important for ecological protection and the maintenance of high-quality standards within the Yellow River basin. Based on the measured runoff data at 11 hydrological stations and meteorological data from 19 meteorological stations from 1956 to 2020 above the Lanzhou hydrological station, including the Daxia, Tao, Huangshui, and Datong Rivers, linear regression and Mann-Kendall tests were used to analyze the variability of runoff series and the influence of driving factors on runoff change. The results showed that the runoff changes at representative hydrological stations in the study area increased and decreased from 1956 to 2020. The source region and northwest rivers showed slight increases in runoff, whereas the southeast rivers showed a decrease. Overall, the non-source rivers showed a decreasing trend. There was an abrupt runoff change at each station around 1990, with the runoff in the 1990s exhibiting the lowest values. A gradual increase was then observed, with the runoff reaching or exceeding the previous maximum value around the year 2020. Contrary to the trend of annual runoff, the winter runoff at all stations in the study area showed increases, except for the Daxia River, which was mostly influenced by anthropogenic activities. Changes in precipitation and snowmelt water were the main causes of runoff change in the source region, whereas the increase in regional water use and water consumption resulted in a decrease in runoff in non-source areas. Snow cover played a key role in increasing runoff after 2010 and alleviating drought in the 1990s, while permafrost degradation was the main reason for the change in the annual runoff processes slowing down throughout the year, except in winter.

  • Min ZHENG, Min LUO, Binbin PAN, Duofu CHEN
    Advances in Earth Science. 2023, 38(3): 236-255.

    Benthic O2 uptake is a robust proxy for organic matter mineralization in marine sediments. Therefore, studying sediment oxygen consumption is conducive to understanding the global marine carbon cycle. Three approaches are commonly used to measure oxygen consumption at the SWI: oxygen microprofiling, benthic incubation, and the eddy covariance technique. The emerging eddy covariance technique is a non-invasive approach that can measure benthic O2 flux on a relatively large scale, and thus has wide application. Globally, benthic oxygen consumption is controlled by water depth and primary productivity in surface water. In addition, benthic diffusive oxygen uptake and total oxygen uptake decreased significantly and their ratios approached 1 with increasing water depth. This was mainly caused by the substantial decrease in benthic biomass and resulting benthic oxygen consumption with increasing water depth. Despite more than half a century of observations of benthic oxygen consumption, in-situ data remain scarce, especially in deep-sea and extreme marine environments. A large amount of measured data are still single-point observations within a short time period. Against the background of global warming and the increasing impact of human activities on marine environments and ecosystems, it is necessary to conduct high-precision and long-term in situ observations of benthic oxygen consumption globally.

  • Xueyun LU, Jianqing JI, Lining WANG, Dalai ZHONG
    Advances in Earth Science. 2023, 38(3): 270-285.

    Climate-tectonic-erosion interactions have recently become a research hotspot in Earth science as a significant aspect of geosphere interactions near the Earth’s surface. Here, studies related to climate-tectonic-erosion interactions over the past 30 years are reviewed mainly from three fields: analytical treatment, numerical modelling, and field verification, and it is suggested that advancement of near-surface geosphere interaction research has been limited by the thought pattern of cause and effect. Orogenic belts are best viewed as evolving open systems driven by energy from endogenous and exogenous forces. An orogenic system with a tendency towards equilibrium will respond to perturbations in endogenous and exogenous forces and also exert impacts on relatively independent endogenous and exogenous factors. Beyond cause and effect, the system-oriented view of orogenic evolution can resolve controversial issues in the study of climate-tectonic-erosion interactions.

  • Minhua QIN, Aiguo DAI, Renhe ZHANG
    Advances in Earth Science. 2022, 37(9): 963-978.

    The Atlantic Multidecadal Variability (AMV) refers to multidecadal (60~80 year) quasi‐oscillation in North Atlantic sea surface temperatures. The AMV has significant impacts on global and regional climate. However, the fundamental physical mechanisms and processes underlying the AMV remain a hot research topic. Internal ocean dynamics, atmospheric stochastic forcing, and external forcings of either anthropogenic or natural origins all have contributed to the AMV. Improved knowledge of the AMV is of great scientific importance for understanding the causes of global climate change as well as for decadal climate predictions. This paper reviews the definition and main characteristics of the AMV, its underlying mechanisms and climate impacts. This study also discusses the key topics and outstanding issues in AMV research.

  • Yifan DING, Jun TIAN
    Advances in Earth Science. 2022, 37(11): 1165-1180.

    The Indo-Pacific warm pool is an important global source of heat and water vapor that plays a key role in climate systems. The opening and closing of the Indonesian seaway controls the transport of water and heat between the Indo-Pacific warm pools and has a significant influence. Since the Late Miocene, the Pacific Plate has subducted westward toward the Eurasian Plate, the Indian and the Eurasian plates have undergone strong land-land collision, and the Australian Plate has begun to subduct northward at 10 Ma. These tectonic movements have gradually closed the Indonesian seaway, changing the ocean circulation between the western Pacific Ocean and the eastern Indian Ocean. During the Pliocene, the source of the Indonesian Through Flow (ITF) changed from the high-temperature, high-salinity South Equatorial Pacific to the low-temperature, low-salinity North Equatorial Pacific. Consequently, the western Pacific warm pool gradually strengthened, the sea surface temperature of the eastern Indian Ocean decreased, and the subsurface salinity decreased. Changes in the ITF not only contributed to the aridification of northwestern Australia and eastern Africa but also reduced tropical heat transport to the higher latitudes of the Northern Hemisphere. The change in meridional heat transport likely promoted the formation of the Arctic ice sheet, but the specific mechanisms and magnitude of its impact need to be further studied.

  • Longzheng ZHOU, Jingong CAI, Xu LI, Jing CHAO, Zheng LI
    Advances in Earth Science. 2022, 37(7): 709-725.

    Clarifying the occurrence, form, content, and distribution of water in shale is conducive to further understanding the internal relationship between “oil (gas)-water-rock”. This line of research has implications in guiding the generation, storage, migration, exploration, and development of shale oil and gas. Considering that the current classification of different waters in shale is complex and inconsistent, a classification approach based on the occurrence state of water is proposed combined with existing classification methods. Specifically, it categorizes water into free-state movable water, volume-filled capillary-bound water, surface-adsorbed bound water film, and structured water of ionic state. Irreducible water is the “competitor” of the storage space and an “obstacle” in the transportation channel for oil (gas). The bound water film occupies the effective adsorption sites of shale oil and gas, and the capillary-bound water blocks small pores and throats. Simultaneously, the occurrence state of water changes with changes in the minerals and organic matter, thus affecting the wettability of the reservoir and the exploration and development of shale oil and gas. In addition, the influence of minerals, organic matter, and pore characteristics on the occurrence-related mechanisms of water in shale were discussed, and thermal analysis and nuclear magnetic resonance detection methods were applied to understand the content, location, and microscopic distribution characteristics of different occurrences of water. This was done to provide a theoretical basis for the efficient development of shale oil and gas.

  • Bingke ZHAO, Jie TANG, Xiaotu LEI, Xuefen ZHANG, Wansuo DUAN, Hong LI, Zhiqiu GAO, Chuanhai QIAN, Xuwei BAO, Jingyao LUO, Shuai ZHANG
    Advances in Earth Science. 2022, 37(8): 771-785.

    The China National Key Research and Development Program of China “The experiment of a multi-platform collaborative field campaign on offshore typhoon (2018YFC1506400)” was established to meet the needs of the country for typhoon prevention and disaster reduction. Additionally, the project aims to solve the lack of direct typhoon observation data, which restricts the development of typhoon science and the improvement of operational forecasting ability in China. Since the establishment of the project in December 2018, field observation-diagnosis and theoretical analysis based on observational data-numerical simulation and data verification have been used to adapt and transform new typhoon detection equipment independently developed by China in recent years. This included high-altitude unmanned aerial vehicles and stratospheric airships and the complete design of the “land-ocean-air-sky” three-dimensional collaborative observation scheme for offshore typhoons. Furthermore, multi-platform collaborative field observation experiments were implemented for 16 offshore target typhoons and the parameterization scheme of the physical process of the typhoon model based on the analysis of multi-source direct observation data was modified and applied to the national-level typhoon operational numerical prediction model. This significantly improved the performance and forecast accuracy of the track and intensity of the typhoon operational numerical prediction model and precipitation forecast by 5% and 3%~5%, respectively. Here, the progress of the program is summarized and associated scientific issues are discussed. The typhoon multi-platform observation system and collaborative observation scheme constructed by the project will lay the foundation for the construction of operational direct typhoon observation in offshore areas of China and is expected to realize the progress from the current “follow-up” to “parallel” and partial “lead.”

  • Yaojie WANG, Lei ZHONG, Mingxing CHEN, Renmin YUAN, Xiaoqing WU, Xuexing QIU, Nan GE, Meilin CHENG, Peizhen LI
    Advances in Earth Science. 2022, 37(7): 756-770.

    Anthropogenic heat flux is an important term of urban energy budget. Estimation of the anthropogenic heat flux is critical for the study of urban climate and heat island effect. Therefore, the anthropogenic heat flux of Hefei from 2013 to 2020 was estimated based on the energy balance equation method using Landsat 8 satellite data and ERA5 reanalysis data. Land surface characteristic parameters and each component of the energy balance equation was quantitatively validated against in-situ measurements, then the spatiotemporal distribution of anthropogenic heat flux was analyzed. The results showed that: The retrieval algorithm of surface temperature and the estimation scheme of downwelling long-wave radiation suitable for urban are established. The root mean square errors of surface temperature and downwelling long-wave radiation are 2.33 K and 9.26 W/m2, respectively. The estimated net radiation flux, sensible heat flux, latent heat flux and anthropogenic heat flux are in good agreement with the in-situ observations, and the root mean square errors are 82.00 W/m2, 69.51 W/m2, 55.19 W/m2 and 75.47 W/m2, respectively. The spatial distribution of anthropogenic heat flux is relatively concentrated, and anthropogenic heat flux in urban areas is much higher than that over the natural underlying surface; the industrial area in the main urban area is the largest anthropogenic heat flux emission area throughout the year; the anthropogenic heat flux has distinct seasonal variation, with the largest in summer, the second in spring and the smallest in autumn and winter; there are obvious differences in anthropogenic heat flux on different surface cover types, the urban area is the largest, followed by farmland, and the forest and water body are small, the seasonal average of the urban area in spring, summer, autumn and winter are as follows: 280 W/m2, 321 W/m2, 203 W/m2 and 131 W/m2, respectively. The research results have important scientific significance and application value for evaluating the energy emissions, development status, layout planning and urban regional climate of large and medium-sized cities.

  • Guoxiang CHEN, Zhibao DONG, Aimin LIANG, Weikang SHI, Xiaokang LIU, Weige NAN, Ziyi BAI, Zheng CHI
    Advances in Earth Science. 2022, 37(8): 786-797.

    Talus slopes are widely developed hillslope landforms accumulated by debris at the foot of escarpments. As the key area for understanding the alpine sediment cascade in basin-mountain systems, talus slopes contain abundant information on regional rock weathering rates and climate change. Based on geomorphological research of talus slopes in alpine periglacial areas worldwide, we summarized the developmental environment, geomorphic types, morphological characteristics, and sedimentary structures and rates. The key to understanding the geomorphological evolution of talus slopes lies in accurately judging their morphological characteristics and sedimentary processes. The deposition rate of talus slopes obtained by measuring key factors such as its thickness and volume using advanced technology allows to ascertain the weathering rate of regional alpine escarpments and deduce the evidence of regional paleoclimate changes. Future research on talus slopes in the dry denudated mountains in China needs to be conducted systematically and thoroughly with modern technology in terms of their type and distribution, sedimentary structure and evolution, and chronology to provide key evidence for determining the temporal and spatial variation characteristics of regional mountain weathering rates and paleoclimate changes in Asia.

  • Juanhao YANG, Yongsheng WANG, Qiao BAI, Weiwei MA
    Advances in Earth Science. 2022, 37(8): 871-880.

    Rock materials in an orogen are usually large-scale denuded and transferred to their surrounding basins during the post-collisional stage. Therefore, studies on sedimentary rocks in these basins are helpful for better understanding the evolutionary history of the orogen. The Hefei Basin, located north of the Dabie Orogen, was filled with clastic materials from the orogen, recording key information on its uplift and denudation history. In this study, sandstones of the Lower Cretaceous Zhuxiang Formation and siltstones of the Paleogene Dingyuan Formation in the central Hefei Basin were selected for detailed detrital zircon LA-ICP-MS U-Pb dating. The detrital zircon age frequencies in the Zhuxiang Formation show Triassic and middle Neoproterozoic age clusters, whereas the Dingyuan Formation has a predominant middle Neoproterozoic age cluster, with secondary age clusters in the Paleoproterozoic and the Archean. All the samples lacked or contained few Early Cretaceous zircon ages. Combined with the results of previous studies, it can be concluded that the provenance of the Zhuxiang Formation is mainly the Dabie Orogen and that its formation age corresponds to the late stage of the Fenghuangtai Formation in the southern Hefei Basin. Different detrital zircon age frequencies in different samples correspond to the process in which the high-pressure and ultrahigh-pressure rocks were gradually denuded in the Dabie Orogen during the Early Cretaceous. In the Paleogene, the Hefei Basin was surrounded by a series of uplifts, which greatly reduced the diversity of clastic material sources of the Paleogene Dingyuan Formation. Because the detrital zircon age frequencies of the Dingyuan Formation are consistent with those of the Sinian strata in the South China Block, it can be inferred that the source materials of the Dingyuan Formation mainly come from the Sinian of the Zhangbaling Uplift. The provenance of sedimentary rocks in the Hefei Basin changed from the Dabie Orogen to the Zhangbaling Uplift at the end of the Late Cretaceous or the beginning of the Paleogene.

  • Li GAO, Jiawen ZHENG, Zuosen ZHAO, Yuelin LUO, Pengfei REN, Guohua YAO
    Advances in Earth Science. 2022, 37(12): 1211-1222.

    Ensemble prediction, one of the most rapid developments in numerical weather prediction, has presently become a vital basis for accurate forecasting and assessment of product abundance. In the past three decades, accompanied by the rapid developments in prediction research and techniques, a significant progress has been made in operational technology and systems for ensemble prediction. As the output end of the information facing downstream users in the ensemble prediction chain, the post-processing system has been an integrated platform for the generation of numerous ensemble data, the unification of product-making functions, and the intensification of multilevel forecasting approaches and techniques. In this study, a comprehensive local-to-global review was first conducted for the historical development, current stage, and future direction of the post-processing system and technology for ensemble prediction. Second, the following seven main functions of the post-processing system were summarized: Standardized output and distribution of ensemble data; Calculation of ensemble mean and spread statistics; Analysis of synoptic and climatological diagnostics; Generation and issuance of deterministic and stochastic ensemble prediction products; Extraction and interpretation of big ensemble data and information; Calibration and improvement of deterministic and stochastic ensemble forecasts; User-customized product services and visualization. Finally, the unified post-processing system in the China Meteorological Administration-Global Ensemble Prediction System/Regional Ensemble Prediction System (CMA-GEPS/REPS) was discussed in terms of the above main functions. The focus was on finding ways to make better use of the big ensemble data and information from the CMA-GEPS/REPS real-time forecasts to study. Further, the intent was to develop a variety of new ensemble products, particularly including the extreme forecast index, Madden-Julian oscillation, western-Pacific subtropical high, and south-Asian high, as well as learning to apply them to realistic operational forecasting. Overall, the post-processing technique is becoming a predominant research and development direction, building on the advantages of ensemble prediction ranging from high forecast accuracy to actionable insights with significant social, environmental, and economic benefits.

  • Xing QIU, Yuxiang DONG
    Advances in Earth Science. 2022, 37(8): 811-821.

    As climate change intensifies the frequency and magnitude of extreme weather events such as storm surges, coastal dunes are receiving increasing attention for their storm surge resilience, and research on the response of coastal dunes to storm surges has made remarkable progress. In view of the cross-shore, alongshore, and cluster responses of coastal dunes to storm surges, a more in-depth study has recently been conducted on their characteristics and mechanisms. Significant progress has been made in terms of the expansion of study areas, improvement of response characteristics, depth of response mechanisms, and innovation of research techniques and methods. However, theoretical and methodological systems still need to be improved, and insight on the influence mechanism of coastal dune elements still needs to be deepened. Additionally, the recovery of coastal dunes in morphology response has not been properly quantified, and comparative studies at the regional scale still need to be developed. In the future, based on a sound theoretical and methodological system, research should be enhanced to better understand these factors.

  • Shuying LENG, Liang ZHANG, Renhao WU, Lifang WANG, Hui WANG, Chengfeng LE
    Advances in Earth Science. 2022, 37(12): 1299-1308.

    To better understand the application process for researchers and improve the quality of proposals and final reports of funded projects, this study analyzed the processes of application, review, and funding of proposals in the fourth division of the Earth Science Department (that is, the Ocean and Polar Science Division). Further, this study sorted problems during the proposal acceptance and external review process and summarized the performance of funded projects finalized in 2021. Compared to 2021, five more institutions submitted the General Program, Youth Science Fund, and Less Developed Regions Fund proposals to the Ocean and Polar Science Division. The application numbers for all the three types of funding rose by 13.8%, 10.4%, and 10.6%, respectively, wherein subcodes D0611 (Ocean Engineering and Environmental Responding ) and D0613 (Oceanic Energy and Resource) had the highest increase rate. The number of applications belonging to the original innovation and interdisciplinary categories increased; however, their ratio decreased slightly. The final reports of funded projects finalized in 2021 had such issues as insufficient summarization and a low acknowledgment ratio for the funding.

  • Juhua XIONG, Yang GAO, Hao WU, Xin LI, Dan LIANG, Wenping YU, Meihong MA, Yongqiang ZHOU, Xiaofeng WANG
    Advances in Earth Science. 2022, 37(12): 1245-1255.

    The National Natural Science Foundation of China (NSFC) has received widespread attention and is the primary funding institution for fundamental research in China. This study analyzed the submission and reception of proposals to the Division of Geography of the Department of Earth Sciences of the National Natural Science Foundation of China in 2022. The proposal reviews and grant funding processes were examined in terms of three subdisciplines, namely, Physical Geography, Human Geography, and Geographic Informatics; three types of projects, namely, General Program, Young Scientists Funding Program, and Regional Funding Project; and four types of scientific attributes and issues formulated by the NSFC. Issues with the proposal submission and peer review were also pointed out. Consecutively, for the funded projects at the end of 2021, we analyzed the closeout achievement of projects, focused on their representative achievements, and identified the main problems in the project progress and closing reports.

  • Qingxiang ZHONG, Yu ZHANG, Zhen TAO, Yicong HE, Di WU, Peisong LIN
    Advances in Earth Science. 2023, 38(1): 44-56.

    Selenium (Se) is an essential micronutrient for many organisms (including soil microorganisms, plants, animals, and humans), and has dual biological effects on plants, animals, and humans. The migration, transformation, and enrichment of Se in soil-plant systems have attracted considerable attention for more than half a century. There are five forms of soil Se: soluble Se (SOL-Se), exchangeable carbonate-bound Se (EXC-Se), iron-manganese oxide-bound Se (FMO-Se), organic matter-bound Se (OM-Se), and residual Se (RES-Se), of which SOL-Se and EXC-Se are characterized by bioavailability. OM-Se can be converted into soluble Se by the decomposition of organic matter and is a potentially effective selenium source in soil. The Se content of different plants depends on the soil-available Se content and the Se absorption and enrichment levels of different plants. Therefore, the bioavailability of soil Se plays a critical role in determining the Se content in the food chain, and soil-available Se can improve plant stress resistance by regulating the rhizosphere environment and metabolic processes. Soil-plant system Se migration is a complex biogeochemical process that is dominated by coupled crustal movement, parent rock properties, climate, geomorphology, soil environment (physico-chemical properties and microbial activity) conditions, soil Se content and chemical properties, plant species and biological habits, and field management processes. For the rational utilization of soil Se resources, research needs to focus on Se migration, transformation, and enrichment in plants, especially the main food crops, vegetables, fruit trees, and Authentic Chinese herbs. This study provides basic data for Se biofortification in Se-deficient areas, and crop selection, food selection, and risk assessment in Se-rich areas.

  • Minggui ZHENG, Ming YU, Qiurong FAN, Yuhua LIN
    Advances in Earth Science. 2023, 38(4): 377-387.

    The inconsistency between the supply and demand of lithium carbonate is becoming increasingly serious. Scientific prediction of the future lithium carbonate demand is of great significance for China’s lithium resource production, import and export arrangements, and national energy policy formulation. Based on a combined model of grey correlation analysis and the ARIMA-GM-BP neural network, data on the driving variables of China’s per capita GDP, industrial structure, urbanization level, grease production, ceramic production, glass production, air conditioning production, lithium-ion battery production, and new energy vehicle production in 2002-2021 were selected to predict China’s lithium carbonate resource demand between 2025 and 2035. The results show that the selected driving variables are highly correlated with China's lithium carbonate resource demand, and the combined model is more accurate than a single model. The predicted average quantity demand for lithium carbonate in 2025, 2030, and 2035 is 0.42 million tons, 0.69 million tons, and 1.03 million tons, respectively. Accordingly, some policy suggestions have been proposed.

  • Shaopeng CHEN, Yuefang DUAN
    Advances in Earth Science. 2023, 38(1): 86-98.

    Examining the research status, focus, and developing trend of the agricultural carbon effect in China can provide references to researchers and improve the breadth and depth of research on the agricultural carbon effect. In this study, 708 high-quality papers published from 2009 to 2021 in the Chinese Academic Journal Network Publishing Database were retrieved as basic data. CiteSpace software was used for a visualized analysis of information, including authors, institutions, and keywords. The results suggested that, in terms of research status, the number of papers experienced a high-speed growth period and a stable growth period; With their authors being mostly scattered and only some being concentrated. Most institutions conduct their research independently. In terms of research focus, the core words found throughout the existing research were agricultural carbon emissions, carbon emissions, low-carbon agriculture, greenhouse gas, farmland ecosystem, and carbon sink. Six clusters were identified, namely agricultural carbon emissions, soil carbon sequestration, carbon footprint, low-carbon agriculture, agricultural carbon emissions efficiency, and carbon emissions reduction. Additionally, 12 burst terms were observed, namely soil carbon sequestration, soil organic carbon, low-carbon agriculture, greenhouse gas emissions reduction, low carbon economy, carbon sequestration and emissions reduction, greenhouse gas, countermeasures, carbon sink, lmdi model, carbon sequestration rate, and agricultural carbon emissions efficiency. Five categories of research focus were summarized, namely agricultural carbon source/sink, agricultural carbon sequestration, agricultural carbon emissions reduction, agricultural carbon footprint, and low-carbon agriculture. In terms of research trends, the keywords were concentrated in papers published from 2009 to 2014. Research on the agricultural carbon effect shows trends of increasing research popularity, decreasing research topics, and increasing research methods. Finally, the prospect of the agricultural carbon effect in China was based on five aspects: mid-small areas, comprehensive perspective, the entire industry chain, farmer behavior, and grain security.

  • Qiting ZUO
    Advances in Earth Science. 2023, 38(1): 1-8.

    Water resources are indispensable for human survival and economic and social development. Ensuring sustainable utilization of water resources is important for sustainable economic and social development; therefore, studying the sustainable utilization of water resources and their contribution to water control in China is essential. Based on previous research, this study expounds the background of the sustainable utilization of water resources and the history of foreign and domestic research. Here, the research on sustainable utilization of water resources in China was first divided into three stages: early stage (before 2000), 2000-2010, and after 2010. We then introduced the representative results and research status based on the summary of China's thoughts on water control since 2000, and the contribution of the research on sustainable utilization of water resources to modern water control in China is expounded. Finally, the developmental needs of water control and the research prospects of the sustainable utilization of water resources under the new situation were analyzed. These findings can provide a reference for further research on the sustainable utilization of water resources and the formulation of water control strategies in China.

  • Shaofeng JIA, Yuan LIANG
    Advances in Earth Science. 2023, 38(3): 221-235.

    The aim of this study is to scientifically implement water diversion projects and effectively provide water security for high-quality development and environmental protection. The research progress of water diversion projects is reviewed in terms of industry standards, specifications, and related studies. It was found that water demand prediction tends to be overly high, the integrity of comprehensive benefit evaluation needs to be improved, the standard of ecological compensation mechanism remains incomplete, and post-evaluation and tracking work is insufficient. To support the spatial equilibrium of water resource allocation and the construction of national water networks, future water diversion projects need to strengthen environmental protection and whole-stage follow-up evaluation, perform full cost pricing, perfect the investment and financing system, and improve information and intelligent management.

  • Jianguo REN, Hang CHU, Dawei LÜ, Wenjie SUN, Huanxin SONG, Suping LI, Mingjian CAO
    Advances in Earth Science. 2022, 37(12): 1256-1264.

    In order to provide effective instructions for geological researchers and scientific research units in applying the National Natural Science Foundation of China in 2023 year, we summarized the applications of the proposals managed by Division of Geology of National Natural Science Foundation of China in 2022. Two characteristics are as follows: Firstly, the number of project applications in 2022 increased comparing to 2021 except the Outstanding Youth Science Foundation; Secondly, the number of quality evaluations of the General Program, the Young Scientist Fund and Fund for Less Developed Regions all increased slightly. In addition, the project progresses submitted in January 2022 and the concluding report submitted at the end of 2021 were summarized, and the research progress made in the major discipline directions in 2022 were described in detail.

  • Feng CAO, Jianhua HE, Yuanyuan WANG, Hucheng DENG, Qinglong XU
    Advances in Earth Science. 2022, 37(7): 742-755.

    The Hechuan area is rich in dense sandstone gas resources in the second member of the Xujiahe formation, and the complex geological conditions in this area have a great impact on the current exploration and development of oil and gas resources. One of the issues resulting from this complexity is an unclear understanding of how present-day in-situ stress direction restricts the later horizontal well deployment and the promotion of fracture transformation. Based on an analysis of wave velocity anisotropy, differential strain, and paleomagnetism, combined with special logging and microseismic monitoring data, the applicability of various types of in situ stress direction testing frameworks in dense sandstone reservoirs was evaluated, and the distribution of present-day in situ stress directions in the Hechuan area were determined. The results show that the maximum principal stress orientation of the second member of the Xujiahe Formation in the Hechuan area is mainly distributed between N103.1°E-N134.3°E, and the azimuth angle of the average maximum principal stress is N117.4°E; that is, the present-day maximum principal stress orientation of the sandstone in this area is NWW-SEE. The change in the direction of the in situ stress in the plane is not significant, and its weaker in situ stress deflection is mainly influenced by the sedimentary structure. In the Hechuan area, the dense sandstone in the second member of the Xujiahe Formation is relatively homogeneous, and the anisotropy is weak; therefore, the wave velocity anisotropy test cannot be applied in this area. The experimental test results of differential strain combined with paleomagnetism are highly congruent with the results above. Therefore, the test more applicable to sandstone formations in this area, specifically the ones with a homogeneous and weak anisotropy, is microseismic monitoring and well wall image logging to evaluate the in-situ stress direction. Combined with the direction of the in situ stress and fracture development, the recommended orientation for horizontal well deployment is N40°E-N55°E.