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Storage, form, and influencing factors of karst inorganic carbon in a carbonate area in China

Science China Earth Sciences 2024年第3期67卷 725-739页

作者： Chaochao DU Xiaoyong BAI Yangbing LI Qiu TAN Cuiwei ZHAO Guangjie LUO Luhua WU Fei CHEN Chaojun LI Chen RAN Sirui ZHANG Lian XIONG Fengjiao SONG Biqin XIAO Zilin LI Yingying XUE Mingkang LONG Qing LUO Xiaoyun ZHANG Minghui LI Xiaoqian SHEN Shu YANG State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China School of Geography and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China CAS Center for Excellence in Quaternary Science and Global Change Xi'an 710061China guizhou provincial Key Laboratory of Geographic State monitoring of watershed Guizhou Normal CollegeGuiyang 550018China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China

Carbonate rock chemical weathering carbon sinks reduce the rate of increase of the atmospheric CO_(2) concentration and global warming. However, uncertainty still exists in the estimation results of carbonate rock chemical weathering carbon sink fluxes(CCSF), and the contributions of climate change and ecological restoration to the CCSF are not clear. To this end, we compiled published site data on ion concentrations in different watersheds in China and used a classical thermodynamic dissolution model to reassess the potential and spatial and temporal patterns of the CCSF in China from 1991 to 2020. We quantified the contributions of temperature(MAT), precipitation(MAP), evapotranspiration(ET), soil water(SM), and the normalized difference vegetation index(NDVI) to the CCSF. The results revealed that(1) China's CCSF was 22.76 t CO_(2)km^(-2)yr^(-1), which was higher than the global average(15.77 t CO_(2)km^(-2)yr^(-1)). The total carbonate rock chemical weathering carbon sink(CCS) was 4772.67×10^(4)t CO_(2), contributing 14.91% of the global CCS through a carbonate rock area of 252.98×10^(4)km^(-2).(2) China's CCSF decreased gradually from southeast to northwest, with values of 33.14, 12.93, and7.27 t CO_(2)km^(-2)yr^(-1)in the southern karst, Qinghai-Tibetan karst, and northern karst regions, respectively.(3) The overall CCSF in China exhibited an increasing trend from 1991 to 2020, with a rate of increase of 0.16 t CO_(2)km^(-2)yr^(-1).(4) The contributions of the MAP, MAT, ET, SM, and NDVI to the CCSF were 63.3%, 3.02%, 27.5%, 3.1%, and 3.05%, respectively. Among them, the increase in precipitation was the main contributor to the increase in the CCSF in China over the last 30 years, while the enhancement of ET offset part of the positive contribution of the increase in precipitation to the CCSF. In conclusion, the results of this study provide a systematic quantification of the magnitude, the patterns, and the influencing factors of CCS over a long time series in

关键词： Carbonate rocks Carbon sinks Patterns Influencing factors Thermodynamic dissolution modeling

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Rainfall and Tillage Impacts on soil Erosion of Sloping Cropland with Subtropical Monsoon Climate- A Case Study in Hilly Purple soil area, China

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Journal of Mountain Science 2015年第1期12卷 134-144页

作者： TANG Jia-liang CHENG Xun-qiang ZHU Bo GAO Mei-rong WANG Tao ZHANG Xi-feng ZHAO Pei YOU Xiang Key Laboratory of Mountain Environment Evolution and Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences provincial monitoring station of soil and water conservation

Under global warming, storm events tend to intensify, particularly in monsoon-affected *** an important agricultural area in China, the purple soil region in the Sichuan Basin, where it has a prevailing monsoon climate, is threatened by serious soil erosion. Tillage operations alter runoff and soil erosion processes on croplands by changing the physical properties of the soil surface. To clarify the relationship between tillage and soil erosion in the purple soil region, three different tillage practices in this region were investigated at the plot scale over 4 years: bare land with minimum tillage(BL),conventional tillage(CT) and seasonal no-tillage ridges(SNTR) which was initially designed to prevent soil erosion by contoured ridges and no-tillage techniques. The results showed that although there were no significant differences in the surface runoff and soil erosion among the three practices, BL causedrelatively high surface runoff and soil erosion,followed by CT and SNTR. Classification and comparison of the rainfall events based on cluster analysis(CA) verified that the surface runoff was not significantly different between most intensive event and long intensive events but was significantly different between most intensive and short and medium-duration events. Only the rainfall events with the highest rainfall intensity could trigger serious soil erosion, up to 1000 kg ha-1 in the region. Further detailed investigations on the effects of tillage operations on the soil erosion in a subtropical region with a monsoon climate are needed to provide a basis for modeling catchments and designing better management practices.

关键词：亚热带季风气候土壤侵蚀过程耕作方式降雨强度紫色土区农田径流中国丘陵

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Using Natural Radionuclides to Trace Sources of Suspended Particles in the Lower Reaches of the Yellow River

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Journal of Ocean University of China 2024年第1期23卷 99-108页

作者： ZHANG Han BURNETT CWilliam ZHANG Xiaojie ZHAO Shibin YANG Disong NAN Haiming YU Zhigang XU Bochao Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahasseeFL 32306USA North China Sea Environmental monitoring Center State Oceanic AdministrationKey Laboratory of Ecological Prewarning and Protection of Bohai SeaMNRQingdao 266033China Shandong provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266033China

Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and *** analyzed the activi-ties and distribution characteristics of multiple natural radionuclides(238U,226Ra,40K,228Ra,7Be and 210Pbex)on size-fractionated SPM at the Lijin Hydrographic station(Huanghe or Yellow River)every month over a one-year *** showed that medium silt(16–32µm)was the main *** expected,the activity of each radionuclide decreased with an increase of particle *** examined the sources of SPM with different particle sizes using activity ratios of 226Ra/238U,228Ra/226Ra,40K/238U and 7Be/210Pbex,and concluded that SPM with different particle sizes originated from different *** results indicate that fine SPM(soil along the lower reaches of the Yellow River,while coarse SPM(>32µm)was mainly derived from resuspension of riverbed *** high runoff periods,the concentration of SPM increased significantly,and the pro-portion of fine particles originating upstream *** occurring radioactive isotopes,especially on size-fractionated par-ticles,are therefore seen as useful tracers to understand the sources and behaviors of riverine particles transported from land to sea.

关键词： the Yellow River suspended particulate matter size-fractions radionuclides sediment sources water elutriator

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Impacts of different surface features on soil detachment in the subtropical region

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International soil and water conservation Research 2021年第4期9卷 555-565页

作者： Qianhong Ma Keli Zhang Zihao Cao Zhicheng Yang Mengyao Wei Zaike Gu State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Teacher Education Hebei Normal UniversityShijiazhuangHebei 050024China guizhou provincial monitoring station of soil and water conservation GuiyangGuizhou 550002China

Near-surface features have a great influence on runoff and detachment processes by overland flow,but the contributions are still unclear on steep slopes with yellow soil in subtropical humid *** scouring experiments were conducted to investigate how near-surface features affect hydraulic parameters and detachment rate by overland *** treatments and a baseline(disturbed rootless bare cropland)were designed to identify the contributions from stem-leaves,litter,biological soil crusts(BSCs),root systems and non-disturbance,*** results showed that(1)the values of velocity,Reynolds number and Froude number for vegetated slopes were significantly lower than that of baseline,and stem-leaves made a greater contribution(average of 47.30%)to reducing kinetic energy than the other features;(2)the total contribution rate of grassland was 99.38%,and of this total,1.19,1.44,2.49,49.79 and 44.47%reductions were attributed to the stem-leaves,litter,BSCs,root systems and non-disturbance,*** system and non-disturbance dominated the detachment rate reduction;(3)with increasing flow rate or slope gradient,the total contribution rate remained between 98%and 100%;and(4)for each treatment,the relationship between detachment rate and hydraulic parameters remained constant,and the stream power was the best predictor to detachment *** study results are helpful in evaluating the effects of near-surface features on erosion control and providing reference for government decision-makers to choose appropriate soil conservation and management practices.

关键词： Vegetation soil tillage soil erosion Detachment rate Yellow soil

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Study of soil and water conservation Function on Slope with Different Planting Patterns for a Typical Small watershed in Karst Region of guizhou Province

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International Journal of Technology Management 2014年第8期 101-105页

作者： LI Rui guizhou provincial monitoring station of soil and water conservation Guiyang Guizhou 550002 China

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Effects of rainfall and rocky desertification on soil erosion in karst area of Southwest China

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Journal of Mountain Science 2022年第11期19卷 3118-3130页

作者： PAN Li-dong LI Rui SHU Dong-cai ZHAO Li-na CHEN Mei JING Jun School of Karst Science Guizhou Normal UniversityGuiyang 550001China State Engineering Technology Institute for Karst Desertification Control Guiyang 550001China College of Resources and Environment Southwest UniversityChongqing 400715China guizhou Hydrology and water Resources Bureau Guiyang 550002China

monitoring and evaluating the evolution of rocky desertification timely and studying the characteristics of soil erosion under different rainfall patterns are of great scientific significance for regional soil and water conservation,rocky desertification control and ecological environment *** periods of remote sensing image data from 2005 to 2020 were selected to study the evolution characteristics of rocky desertification and its impact on soil erosion in the controlled boundary area of Shibantang hydrological station of Yeji River watershed,guizhou Province,*** to the 408 erosive rainfall events,the soil erosion under different rainfall patterns in the watershed was *** results showed that:erosive rainfall events in the study area were mainly pattern A,accounting for 57.4%of the total rainfall events;the second was pattern B,accounting for 28.9%of the total rainfall events;the rainfall pattern of C occurred *** them,pattern A was the main rainfall pattern leading to soil and water loss and had the largest contribution rate to soil erosion in the *** 2005 to 2020,the area of rocky desertification showed a decreasing trend,accounting for 72.2%from 87.9%.Spatially,rocky desertification has mainly concentrated in the middle south of the watershed since 2010,while the rocky desertification mainly concentrated in the middle and north before *** effects of different grades of rocky desertification on soil erosion were different,and the soil erosion modulus in areas with the medium,severe and extremely severe rocky desertification was generally *** soil erosion modulus estimated by the RUSLE(Revised Universal soil Loss Equation)model was still much higher than that calculated by the data measured by the hydrological monitoring ***,the application of the RUSLE model in karst area needs to be further *** results can provide reference for rocky desertification control,soil erosio

关键词： Erosive rainfall Rocky desertification Spatial-temporal evolution soil erosion Karst

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Global patterns and changes of carbon emissions from land use during 1992e2015

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Environmental Science and Ecotechnology 2021年第3期7卷 17-28页

作者： Shiqi Tian Shijie Wang Xiaoyong Bai Guangjie Luo Qin Li Yujie Yang Zeyin Hu Chaojun Li Yuanhong Deng State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550081Guizhou ProvinceChina School of Geography and Environmental Sciences Guizhou Normal UniversityGuiyang550001China CAS Center for Excellence in Quaternary Science and Global Change Xi'an710061Shanxi ProvinceChina Puding Karst Ecosystem Observation and Research station Chinese Academy of SciencesPuding562100Guizhou ProvinceChina guizhou provincial Key Laboratory of Geographic State monitoring of watershed Guizhou Education UniversityGuiyang550018China

Carbon emissions from land use(ELUC)are an important part of anthropogenic CO_(2) emissions,but its size and location remain uncertain,and our knowledge of the relationship between ELUC and GDP remains *** showed that the carbon emissions directly caused by land use change(direct ELUC)during 1992-2015 was 26.54 Pg C(1.15 Pg C yr^(-1)),with a decreased trend and a net reduction rate of0.15 Pg C yr^(-1).The areas that exhibited reductions were concentrated in South America,Central Africa,and Southeast Asia,and those with increments were scattered in Northwestern North America,Eastern South America,Central Africa,East Asia,and parts of Southeast *** the indirect carbon emissions from the utilization of built-up land(indirect ELUC),it manifested an upward trend with a total emission of 27.51 Pg C(1.2 Pg C yr^(-1)).The total value resulted by global ELUC was $136.3×10^(9) US,and the value of annual was equivalent to 3.7 times the GDP of the Central African Republic in 2015($5.93×10^(9) US yr^(-1)).Among the 79 countries and regions considered in this study,54 represented the upward GDP with increased emissions,and only 25 experienced GDP growth with emission *** findings highlight the pivotal role of land use change in the carbon cycle and the significance of coordinated development between GDP and carbon emissions.

关键词： Land use Carbon emissions Vegetation biomass carbon soil organic carbon Temporal-spatial change

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Elevated methylmercury production in mercury-contaminated soil and its bioaccumulation in rice:key roles of algal decomposition

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Frontiers of Environmental Science & Engineering 2023年第12期17卷 31-45页

作者： Di Liu Yan Wang Tianrong He Deliang Yin Shouyang He Xian Zhou Yiyuan Xu Enxin Liu Key Laboratory of Karst Georesources and Environment(Ministry of Education) Guizhou UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China guizhou Karst Environmental Ecosystems Observation and Research station Ministry of EducationGuiyang 550025China

Algal-derived organic matter(AOM)regulates methylmercury(MeHg)fate in aquatic ecosystems,whereas its role in MeHg production and bioaccumulation in Hg-contaminated paddies is *** and microcosm experiments were thus performed to understand the response characteristics of MeHg concentrations in soil and rice in different rice-growing periods to algal *** to the control,algal decomposition significantly increased soil water-soluble cysteine concentrations during the rice-tillering and grain-filling periods(Psoil-dissolved organic matter(SDOM)during the rice-tillering period(Psoil MeHg concentrations by 25.6%-80.2%and 12.6%-66.1%during the rice-tillering and grain-filling periods,with an average of 42.25%and 38.42%,respectively,which were significantly related to the elevated cysteine in soil and the decrease in SDOM molecular weight(Psoil-rice systems.

关键词： Mercury Methylmercury Algae Organic matter Rice(Oryza sativa L.)

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Impact of a retrogressive thaw slump on surrounding vegetation communities in the Fenghuoshan mountains,Qinghai-Tibet Plateau

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Research in Cold and Arid Regions 2023年第1期15卷 11-17页

作者： Gang Wei LaJia Weisai ZiJie Zhou XinNing Wu SiRu Gao ZiTeng Fu QingBai Wu GuanLi Jiang Environmental Geological Prospecting Bureau of Qinghai Province XiningQinghai 810008China Key Laboratory of Qinghai Environmental Geology XiningQinghai 810008China Qinghai Geological Environment monitoring station XiningQinghai 810008China School of Geological Engineering and Geomatics Chang'an UniversityXi'anShaanxi 710054China State Key Laboratory of Frozen soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Beiluhe Observation station of Frozen soil Environment and Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China

Under global warming,permafrost around the world is experiencing degradation which is especially so on the Third Pole,the Qinghai-Tibet Plateau(QTP),*** thaw slump(RTS)is one of the thermokarst features caused by rapid degradation of ice rich permafrost,which transforms landforms and threatens infrastructures,and even affects the terrestrial carbon *** this work,vegetation communities surrounding a RTS in the Fenghuoshan Mountains of the interior portion of the Qinghai-Tibet Plateau have been investigated to examine the impact from *** investigation indicates that the occurrence of RTS influences the vegetation community by altering their habitats,especially the soil water content,which forces the vegetation community to evolve in order to adapt to the *** the interior part of RTS where it has been disturbed tremendously,alterations have produced a wider niche and richer plant *** favors species of a wet environment in a habitat where it was a relatively dry environment of alpine steppe prior to the occurrence of *** study adds to limited observations regarding the impact of RTS to vegetation community on the QTP and helps us to reach a broader understanding of the effects of permafrost degradation as well as global warming.

关键词： Retrogressive thaw slump Vegetation community Rapid permafrost degradation Global warming Qinghai-Tibet plateau

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Landscape Pattern of Ancient Terraces in Huangping County and Slopeto-Terrace Strategy

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Journal of Landscape Research 2016年第2期8卷 6-12页

作者： LAN An'jun ZHAN Fengli FU Yuwen ZHONG Jiusheng LIU Fayong YOU Boyu School of Geography and Environment Sciences Guizhou Normal University monitoring station of soil and water conservation in guizhou Province Institute of South China Karst Guizhou Normal University Guiyang

Formation and development of ancient terraces proves that slope-to-terrace project is a signifi cant measure for conserving water and soil in mountainous areas. UAV remote sensing technology was applied to obtain RS images with a resolution ratio of 0.1–0.5 m, Arc GIS was applied for data processing, and Fragstats3.3 was used to calculate characteristic indexes, to study landscape pattern of 4 ancient terraces in Huangping County, guizhou Province. The results showed that terrace landscapes and woodland landscapes in the study area account for nearly 80% of the whole landscape(terrace 30%, woodland 50%); mean area of single fi eld is mainly concentrated between 100 m^2 and 200 m^2, and height between 0.7 m and 1.7 m, breadth 0.5 m and 0.6 m; most terraces have a gradient of 5–25°, accounting for 70% of the total number of fi eld. The water and soil conservation concept in the ancient terraces provides references for the slope-to-terrace project and the water and soil loss control of slope farmland.

关键词： Ancient terrace Landscape pattern Slope-to-terrace Huangping County

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