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International Soil and Water Conservation Research 2022年第4期10卷 677-686页

作者： Yun Chen Han Tang Binghui He Zhehao Yan Xiaohong Liu Jiaojiao Qiang College of Resources and environment/Chongqing key laboratory of karst environment Southwest UniversityChina

Root tensile strength is commonly affected by root morphology and fiber content,which combinedly affect the effectiveness of terrace hedgerow on controlling soil erosion in sloping ***,the relationships between these root characteristics are still *** study aimed to compare the root tensile strength,root morphologies,and root fiber contents,and quantify their differences among different plant *** root systems of three terrace hedgerow plant species,i.e.,***,***,and *** *** sampled for detecting root morphologies and fiber contents at different slope positions on a representative hillslope in karst trough *** root specimens were collected to measure root tensile properties for these three plant *** showed that most root morphological parameters were the highest in ***,followed by *** *** plant species presented the same dominant diameter class as<1.0 mm,and root volumes as<1.50 *** with contents closing to 50%was the main fiber type,and increased significantly linearly with the increasing root diameter in both *** and *** highest tensile strength and Young's modulus were found in *** L.,while the best ultimate tensile force and ultimate elongation were displayed in *** diameter showed negative power relationships with tensile strength and Young's modulus,a positive power relationship with ultimate tensile force,and a positive linear relationship with ultimate *** results will deepen the understanding of the terrace hedgerow functions for controlling soil erosion worldwide.

关键词： Soil bioengineering Soil erosion Tensile strength Root diameter Fiber content

Viséan Fossil Plants from the Jiujialu Formation in Central Guizhou Province: Implications for Age of Bauxite and Palaeoenvironment

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 2165-2177页

作者： LUO Chaokun YANG Ruidong GAO Junbo Muhammad UMAIR WANG Longbo GAO Lei College of Resources and environmental Engineering Guizhou UniversityGuiyang 550025China key laboratory of karst georesources and environment Ministry of EducationGuizhou UniversityGuiyang 550025China

Fossil plants from the carbonaceous shale of upper part of the Lower Carboniferous Jiujialu Formation in Lindai bauxite deposit fill a gap regarding the distribution of Early Carboniferous flora in Central Guizhou *** the Lindai plant assemblage is systematically described,and its composition and geological age are *** demonstrates that 9 species in 6 genera of the fossil plants are discovered in this study,and they belong to lycopsids,sphenopsids and ferns,*** on the analysis of the floral composition,the geological age of the Lindai plant assemblage belongs to the Early Carboniferous Visé*** discovery of Lindai plant assemblage not only provides a new fossil evidence to restrict the age of bauxite deposits in Lower Carboniferous Jiujialu Formation of Central Guizhou Province,but also has great significance to further research the palaeoecological setting and floral evolution during the Early Carboniferous.

关键词： fossil plant palaeoecology Viséan Jiujialu Formation Bauxite deposit

Carbon dioxide partial pressure and its diffusion flux in karst surface aquatic ecosystems:a review

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Acta Geochimica 2023年第5期42卷 943-960页

作者： Xingxing Cao Qixin Wu Wanfa Wang Pan Wu College of Resources and environmental Engineering Guizhou UniversityGuiyang 550025China key laboratory of karst georesources and environment Ministry of EducationGuizhou UniversityGuiyang 550025China

Carbon dioxide(CO_(2))emissions from aquatic ecosystems are an important component of the karst carbon cycle process and also a key indicator for assessing the effect of karst carbon *** paper reviewed the CO_(2)partial pressure(pCO_(2))and its diffusion flux(FCO_(2))in karst surface aquatic ecosystems,mainly rivers,lakes,and reservoirs,and their influencing factors summarized the methods for monitoring CO_(2)emissions in karst aquatic ecosystems and discussed their adaptation conditions in karst *** pCO_(2)and FCO_(2)decreased in the order of rivers>reservoirs>lakes,and the values in karst lakes were eventually significantly lower than those in global *** pCO_(2)and FCO_(2)of karst aquatic ecosystems had patterns of variation with diurnal,seasonal,water depth and hydrological cycles,and spatial and temporal *** sources of CO_(2)in karst waters are influenced by both internal and external sources,and the key spatial and temporal factors affecting the CO_(2)emissions from karst rivers,lakes,and reservoirs were determined in terms of physicochemical indicators,biological factors,and bio-genic elements;additionally,the process of human activity interference on CO_(2)emissions was ***,a conceptual model illustrating the impacts of urban devel-opment,agriculture,mining,and dam construction on the CO_(2)emissions at the karst surface aquatic ecosystem is ***,based on the disadvantages existing in current research,we proposed several important research fields related to CO_(2)emissions from karst surface aquatic ecosystems.

关键词： karst area River Lake Reservoir Partial pressure of CO_(2) CO_(2)diffusion flux

Effects of fulvic acid and humic acid from different sources on Hg methylation in soil and accumulation in rice

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Journal of environmental Sciences 2022年第9期34卷 93-105页

作者： Shu Ran Tianrong He Xian Zhou Deliang Yin key laboratory of karst georesources and environment(Guizhou University) Ministry of EducationGuiyang 550025China College of Resources and environmental Engineering Guizhou UniversityGuiyang 550025China Guizhou karst environmental Ecosystems Observation and Research Station Ministry of EducationGuiyang 550025China

Humus is often used as an organic modifier to reduce the bioaccumulation of heavy metals in plants, but the effects of different humus components from different sources on the fate of mercury(Hg) in paddy fields are still unclear. Here, fulvic acid(FA) and humic acid(HA) extracted from composted straw(CS), composted cow dung(CCD), peat soil(PM) and lignite coal(LC) were used to understand their effects on the methylation and bioaccumulation of Hg in paddy soil by pot experiments. Amendments of both FA and HA largely increased the abundance of Hg-methylating microbes and low-molecular-weight organic matters(e.g, cysteine) in paddy soil. They were also found to change the aromaticity, molecular size and Chromophoric DOM concentration of DOM, and resulted in heterogeneous effects on migration and transformation of Hg. All the FA-amended treatments increased the mobility and methylation of Hg in soil and its absorption in roots. Nevertheless, FA from different sources have heterogeneous effects on transport of Hg between rice tissues. FA-CCD and FA-PM promoted the translocation of Me Hg from roots to rice grains by 32.95% and 41.12%, while FA-CS and FA-LC significantly inhibited the translocation of inorganic Hg(IHg) by 52.65% and 66.06% and of Me Hg by 46.65% and 36.23%, respectively. In contrast, all HA-amended treatments reduced the mobility of soil Hg, but promoted Hg methylation in soil. Among which, HA-CCD and HA-PM promoted the translocation of Me Hg in rice tissues by 88.95% and 64.10%, while its accumulation in rice grains by 28.43% and 28.69%, respectively. In general, the application of some FA and HA as organic modifiers to reduce Hg bioaccumulation in rice is not feasible.

关键词： Humic acid Fulvic acid Methylmercury Accumulation Rice

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(P<0.05).It also significantly lowered the molecular weight of soil-dissolved organic matter(SDOM)during the rice-tillering period(P<0.05)and SDOM humification/aromaticity during the grain-filling *** to the control,AOM input increased the abundance of potential Hg and non-Hg methylators in ***,it also greatly increased soil 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(P<0.01).In the early stage(within 10 days of microcosm experiments),the MeHg concentrations in decayed algal particles showed a great decrease(P<0.01),suggesting a potential MeHg source in ***,algal decomposition greatly increased the MeHg concentrations and bioaccumulation factors in rice grains,by 72.30%and 16.77%,***,algal decomposition in Hg-contaminated paddies is a non-negligible factor promoting MeHg accumulation in soil-rice systems.

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

The interspecific competition presents greater nutrient facilitation compared with intraspecific competition through AM fungi interacting with litter for two host plants in karst soil

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Journal of Plant Ecology 2022年第2期15卷 399-412页

作者： Yun Guo Yuejun He Pan Wu Bangli Wu Yan Lin Minhong He Xu Han Tingting Xia Kaiping Shen Liling Kang Qiyu Tan Wenda Ren Yan Sun Qing Li Forestry College Research Center of Forest EcologyGuizhou UniversityGuiyang 550025China key laboratory of karst georesources and environment Ministry of EducationGuizhou UniversityGuiyang 550025China

Litter is the crucial carrier of soil nutrition *** influence of arbuscular mycorrhizal(AM)fungi on nutrient acquisition in plants has been widely ***,in nutrient-deficient karst habitat,how competitive plants utilize nutrients regulated by AM fungi via litter remain largely *** experimental treatments included the inoculation with or without Glomus etunicatum,the litter addition by the mixed leaves of Broussonetia papyrifera and Carpinus pubescens or no addition,and the competition through the intraspecific competition of *** and ***,respectively,and the interspecific competition mixed both *** fungi differently affected plant on nutrient acquisition,increasing nutrients acquisitions of *** in intra-and interspecific competitions while decreasing for *** presented opposite influences on N acquisitions of both plants in interspecific competition with AM fungi,being positive for *** and negative for ***,*** the interaction of AM fungi and litter,nitrogen(N),phosphorus(P)and potassium(K)acquisitions by *** and N acquisition by *** in interspecific competition were all greater than intraspecific *** the interspecific competition,the competitive ability of plants on nutrient absorption presented significant species difference,which of *** on P and K was significantly increased,while was converse for *** on *** conclusion,these results suggest that the interspecific competition presents greater nutrient facilitation compared with intraspecific competition through AM fungi interacting with litter for plants in karst soil.

关键词： arbuscular mycorrhizal fungi intraspecific competition interspecific competition karst nutrient acquisition

Effects of acid mine drainage on photochemical and biological degradation of dissolved organic matter in karst river water

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Journal of environmental Sciences 2024年第1期135卷 26-38页

作者： Linwei Li Xingxing Cao Chujie Bu Pan Wu Biao Tian Yongheng Dai Yeye Ren College of Resources and environmental Engineering Guizhou UniversityGuiyang 550025China key laboratory of karst georesources and environment Ministry of EducationGuizhou UniversityGuiyang 550025China Guizhou karst environmental Ecosystems Observation and Research Station Ministry of EducationGuizhou UniversityGuiyang 550025China

Dissolved organic matter(DOM)can be removed or transformed by photochemical and biological processes,producing the negative effect of transforming organic carbon into inorganic carbon,which plays a vital role in the karst carbon ***,acid mine drainage(AMD)will affect this process,so the degradation of DOM in karst river water(KRW)needs to be studied in this *** this study,to reveal the evolution processes of DOM under photochemical and biological conditions in AMD-impacted KRW,AMD and KRW were mixed in different ratios under conditions of visible light irradiation(VL),biodegradation(BD),ultraviolet irradiation(UV)and ultraviolet irradiation+biodegradation(UV+BD).The average DOC concentrations in samples after mixing AMD and KRW in different proportions decreased significantly(by 23%)in UV+BD,which was 1.2–1.4 times higher than under the other conditions and would lead to a significant release of inorganic *** analysis of the fluorescence parameters via parallel factor analysis(PARAFAC)revealed that the DOM fluorescence components in AMD comprised mainly protein-like substances derived from autochthonous components,while the DOM fluorescence components in KRW were mainly humic-like substances with both autochthonous and allochthonous ***,AMD could promote both the photochemical and biological degradation of DOM in karst receiving streams,resulting in the conversion of DOC to inorganic *** results showed that the synergistic effects of UV+BD and AMD accelerated the degradation of DOM and the release of inorganic carbon in KRW,thus affecting the stability of the karst carbon cycle.

关键词： Acid mine drainage Dissolved organic matter karst river water Photochemical degradation Biological degradation

Air pressure law of a reservoir constructed in karst sinkholes

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Journal of Mountain Science 2024年第3期21卷 1048-1057页

作者： YU Bo TAI Shengping ZHENG Kexun CHEN Shiwan HAN Xiao WANG Senlin ZUO Shuangying Power China Guiyang Engineering Corporation Limited Guiyang 550081China College of Resources and environmental Engineering Key Laboratory of Karst Georesources and EnvironmentMinistry of EducationGuizhou UniversityGuiyang 550025China

karst sinkholes with natural negative landform provide favorable conditions for the pumped storage reservoir construction for less excavation ***,the construction of the reservoir would plug the natural karst channels for water and air,which would cause remarkable air pressure in karst channels when the groundwater level fluctuates.A large laboratory simulation test was carried out to study the air pressure variation of a reservoir built on the karst *** air pressure in the karst channel and inside the model was monitored during the groundwater rising and falling *** showed that the variation of air pressure in the karst channel and the surrounding rock exhibited a high degree of *** air pressure increased rapidly at the initial stage of water level rising,followed by a slight decrease,then the air pressure increased sharply when the water level approached the top of the karst *** initial peak of air pressure and the final peak of air pressure were defined,and both air pressure peaks were linearly increasing with the water level rising *** negative air pressure was also analyzed during the drainage process,which was linearly correlated with the water level falling *** causes of air pressure variation in karst channels of a pumped storage reservoir built on the karst sinkhole were *** initial rapid increase,then slight decrease and final sudden increase of air pressure were controlled by the combined effects of air compression in karst channel and air seepage into the surrounding *** the drainage process,the instant negative air pressure and gradual recovering of air pressure were controlled by the combined effects of negative air pressure induced by water level falling and air supply from surrounding *** work could provide valuable reference for the reservoir construction in karst area.

关键词： Simulation test karst sinkhole Pumped storage reservoir Air pressure Flow rate

Carbon Isotope Gradient of the Ediacaran Cap Carbonate in the Shennongjia Area and Its Implications for Ocean Stratification and Palaeogeography

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Journal of Earth Science 2017年第2期28卷 187-195页

作者： Guangzhe Wang Jiasheng Wang Zhou Wang Can Chen Junxia Yang State key laboratory of Biogeology and environment Geology School of Earth Sciences China University of Geosciences Institute of karst Geology CAGS Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification MLR

The geochemistry and paleogeography of the Doushantuo succession in the Shennongjia area have been insufficiently studied. Here, we report on the carbon and oxygen isotope compositions of Ediacaran Doushantuo cap carbonates from four sections（Longxi, Muyu, Yazikou and Songluo） in the Shennongjia area. A large C-isotopic gradient（~5‰） between the Longxi and Songluo sections, here identified for the first time, is inferred to have been dynamically maintained by photosynthesis in surface waters and anaerobic oxidation of dissolved organic carbon（DOC） in deep waters. Spatial variation in C-isotope chemostratigraphy among the four sections was related to Marinoan post-glacial sea-level elevation changes. At Longxi, a positive δ^（13）C_（carb） shift below the horizon containing tepee-like structure resulted from intense photosynthesis during early regression. A negative δ^（13）C_（carb） shift within the tepee-horizon was triggered by sulfate reduction and freshwater mixing with ^（13）C-depleted dissolved inorganic carbon（DIC） during late regression. A positive δ^（13）C_（carb） excursion in the uppermost part of the cap carbonate was related to enhance primary productivity and organic matter burial during early transgression. At Muyu, the carbon isotopic variation tendency, which is similar to that at Longxi, may have been mildly influenced by the surface water environment. At Songluo, the positive δ^（13）C_（carb） excursion, up to-4‰ in the lower part of the cap carbonate, was probably associated with methanogenesis in deep waters during late transgression to early regression and subsequently disappeared due to decomposition of methane hydrate during late regression. At Yazikou, the consistently stable δ^（13）C_（carb） values around-4‰ indicate that the cap carbonate may have deposited at intermediate water depths. As evidenced by diagnostic sedimentary characteristics of the study sections, the palaeogeographic framework of the Shennongjia area exhibited deepening from SE to NW dur

关键词： Ediacaran Doushantuo cap carbonate carbon isotope stratification palaeogeography,Shennongjia.

The impact of sulfate reduction on the distribution of methylmercury in reservoirs in the city of Guiyang

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Chinese Journal Of Geochemistry 2013年第1期32卷 104-109页

作者： HE Tianrong LI Ting Yang Ruidong LUO Guangjun LANG Xiaofang An Yanling YAN Haiyu key laboratory of karst environment and Geohazard Prevention Guizhou University State key laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences

In this paper, the relationship between sulfate reduction potential and mercury methylation potential was studied in the Aha, Baihua and Hongfeng reservoirs from Guiyang City. The methylmercury (MeHg) concentrations of lake water in the Aha Reservoir were greatly elevated as compared to those of the Hongfeng and Baihua reservoirs, which was correlated with its distinctly high SRB abundance, SO42-, and S2- concentrations. Among the three reservoirs, however, the highest MeHg was observed in in the top several centimenters of pore water profile in the Hongfeng Reservoir where the lowest S2- in pore water occurred. The distributions of MeHg in lake water and pore water showed the highest methylation potential occurred at water-sediment surface for the Aha Reservoir and the in the top several centimenters of sediments for the Hongfeng Reservoir. It is guessed that the highest mercury methylation only occurs at the sites with certain sulfide concentrations.

关键词：硫酸盐还原菌阿哈水库甲基汞贵阳市红枫湖甲基化水浓度孔隙水