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Stable carbon isotope composition and intrinsic water use efficiency in plants along an altitudinal gradient on the eastern slope of Yulong Snow Mountain, China

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Ecological Processes 2024年第2期13卷 218-230页

作者： Feng Jiang Tao Pu Zi-Jing Xue Yan-Wei Ma Xiao-Yi Shi Fu-Xi Shi College of Geography and environmental Sciences Zhejiang Normal University Yulong Snow Mountain Glacier and environment Observation and Research Station/State key laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences key laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of poyang lake watershed College of Forestry Jiangxi Agricultural University

Background Stable carbon isotope composition(δ13Cp) can be used to estimate the changes in intrinsic water use efficiency（iWUE） in plants,which helps us to better understand plants' response strategies to climate *** study focused on the variations in δ13Cpand iWUE for the different life-form plants（i.e.,herbs,shrubs,and trees）along an altitudinal gradient（3300,3600,3900,4100,4300,and 4500 m） on the eastern slope of Yulong Snow Mountain,southeastern margin of the Qinghai-Tibet *** response mechanisms of δ13Cpand iWUE for different life-form plants to altitude were thoroughly analyzed in this mountain *** The δ13Cpvalues of plants on the eastern slopes of Yulong Snow Mountain ranged from-30.4‰to-26.55‰,with a mean of-28.02‰,indicating a dominance of *** δ13Cpand iWUE values varied among different life-form plants in the order of herbs> shrubs> trees,particularly in 3600,3900,and 4300 ***δ13Cpand iWUE values for herbs and shrubs increased with altitude and were mainly controlled by air *** two parameters for trees exhibited a trend of initial decrease followed by an increase with *** 3900 m,the δ13Cpand iWUE values decreased with altitude,influenced by soil ***,above 3900 m,the two parameters increased with altitude,mainly regulated by air *** addition,iWUE was positively correlated with leaf P content but negatively correlated with leaf N:P ratio,especially for herbs and trees,suggesting that P plays a key role in modulating iWUE in this *** The diffe rentiated responses of water availability for different life-form plants to a higher altitudinal gradient are regulated by air temperature,soil moisture,and leaf P content in the Yulong Snow *** results provide valuable insights into understanding the wate r-carbon relationships in high-altitude ecosystems.

关键词： Stable carbon isotope water use efficiency Altitude Life form Yulong Snow Mountain

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Slip distribution inversion of seismic sub-fault dip iteration using gradient based optimizer algorithm

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Geodesy and Geodynamics 2024年第2期15卷 114-121页

作者： Leyang Wang Han Li Ming Pang key laboratory of Mine environmental Monitoring and Improving Around poyang lake of Ministry of Natural resources East China University of TechnologyNanchang 330013China School of Surveying and Geoinformation Engineering East China University of TechnologyNanchang 330013China College of resources and environment Shandong Agricultural UniversityTaian 271018China

This paper considers setting different dips for different sub-faults to fit the actual rupture situation based on the fault rupture of the 2013 Lushan M_(S)7.0 ***,combined with the coseismic GNSS data of the Lushan earthquake,the source parameters and sliding distribution of the Lushan earthquake fault are ***,we use the gradient based optimizer(GBO)in nonlinear inversion to obtain the source parameters of this seismic *** inversion results indicate that the strike of the fault is 206.52°,the dip is 44.10°,the length is 21.92 km,and the depth is 12.79 *** refine the sliding distribution of the seismic fault,the seismic fault is divided into 3×3 ***,we fix the central sub-fault dip of 44.10°;the dip of other sub-faults is obtained by *** that,the model is further divided into a fault layer model composed of 23×19 sub fault slices,and using the Matlab fitting function is used to fit the dip of the 23×19 sub ***,the Lushan seismic fault plane is established as a shovel structure with steep upper and gentle lower,steep south and gentle *** slip distribution inversion results indicate that the depth of the slip peak is 13 km,the corresponding maximum slip momentum is 0.67 m,the seismic moment is 1.10×10^(19)N·m and the corresponding moment magnitude is *** results above are consistent with the research results of seismology.

关键词： Gradient basedoptimizer(GBO) Lushan earthquake Non-planefault model Slid distribution

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Global patterns of soil phosphatase responses to nitrogen and phosphorus fertilization

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Pedosphere 2024年第1期34卷 200-210页

作者： Xiaomei GOU Yongqing REN Xin QIN Xiaorong WEI Jingjing WANG State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau the Research Center of Soil and Water Conservation and Ecological EnvironmentChinese Academy of Sciences and Ministry of EducationYangling 712100China Institute of Soil and water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China River and lake Management Office Shaanxi Provincial Department of Water ResourcesXi'an 710004China College of Natural resources and environment Northwest A&F UniversityYangling 712100China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Quaternary Science and Global Change Xi'an 710061China

Hydrolysis of organic phosphorus(P) by soil phosphatases is an important process of P cycling in terrestrial ecosystems, significantly affected by nitrogen(N) and/or P fertilization. However, how soil acid phosphatase(ACP) and alkaline phosphatase(ALP) activities respond to N and/or P fertilization and how these responses vary with climatic regions, ecosystem types, and fertilization management remain unclear. This knowledge gap hinders our ability to assess P cycling and availability from a global perspective. We performed a meta-analysis to evaluate the global patterns of soil ACP and ALP activities in response to N and/or P addition. We also examined how climatic regions(arctic to tropical), ecosystem types(cropland, grassland, and forest), and fertilization management(experiment duration and fertilizer type and application rate) affected changes in soil phosphatases after fertilization. It was shown that N fertilizer resulted in 10.1% ± 2.9% increase in soil ACP activity but a minimal effect on soil ALP activity. In contrast, P fertilizer resulted in 7.7% ± 2.6% decrease in soil ACP activity but a small increase in soil ALP activity. The responses of soil ACP and ALP activities to N and/or P fertilization were largely consistent across climatic regions but varied with ecosystem types and fertilization management, and the effects of ecosystem types and fertilization management were enzyme-dependent. Random forest analysis identified climate(mean annual precipitation and temperature) and change in soil pH as the key factors explaining variations in soil ACP and ALP activities. Therefore, N input and ecosystem types should be explicitly disentangled when assessing terrestrial P cycling.

关键词： acid phosphatase alkaline phosphatase ecosystem type fertilization management meta-analysis phosphorus cycling phosphorus limitation

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Prediction of discharge in a tidal river using the LSTM-based sequence-to-sequence models

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Acta Oceanologica Sinica 2024年第7期43卷 40-51页

作者： Zhigao Chen Yan Zong Zihao Wu Zhiyu Kuang Shengping Wang key laboratory of Mine environmental Monitoring and Improving around poyang lake of Ministry of Natural resources East China University of TechnologyNanchang 330013China School of Surveying and Geoinformation Engineering East China University of TechnologyNanchang 330013China

The complexity of river-tide interaction poses a significant challenge in predicting discharge in tidal *** short-term memory(LSTM)networks excel in processing and predicting crucial events with extended intervals and time delays in time series ***,the sequence-to-sequence(Seq2Seq)model,known for handling temporal relationships,adapting to variable-length sequences,effectively capturing historical information,and accommodating various influencing factors,emerges as a robust and flexible tool in discharge *** this study,we introduce the application of LSTM-based Seq2Seq models for the first time in forecasting the discharge of a tidal reach of the Changjiang River(Yangtze River)*** study focuses on discharge forecasting using three key input characteristics:flow velocity,water level,and discharge,which means the structure of multiple input and single output is *** experiment used the discharge data of the whole year of 2020,of which the first 80%is used as the training set,and the last 20%is used as the test *** means that the data covers different tidal cycles,which helps to test the forecasting effect of different models in different tidal cycles and different *** experimental results indicate that the proposed models demonstrate advantages in long-term,mid-term,and short-term discharge *** Seq2Seq models improved by 6%-60%and 5%-20%of the relative standard deviation compared to the harmonic analysis models and improved back propagation neural network models in discharge prediction,*** addition,the relative accuracy of the Seq2Seq model is 1%to 3%higher than that of the LSTM *** assessment of the prediction errors shows that the Seq2Seq models are insensitive to the forecast lead time and they can capture characteristic values such as maximum flood tide flow and maximum ebb tide flow in the tidal cycle *** indicates the significance of the Seq2Seq models.

关键词： discharge prediction long short-term memory networks sequence-to-sequence(Seq2Seq)model tidal river back propagation neural network Changjiang River(Yangtze River)Estuary

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Late Holocene hydroclimatic variations at lake Hurleg， Northeastern Tibet Plateau

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Journal of Earth Science 2024年

作者： Aiying Cheng Junqing Yu Yun Li Haicheng Wei Chunliang Gao Lisha Zhang key laboratory of Green and High-end Utilization of Salt lake resources， Qinghai Institute of Salt lakes， Chinese Academy of Sciences Qinghai provincial key laboratory of Geology and environment of Salt lakes Haixi Prefecture Salt lake Administration of Qinghai Province

High-resolution， continuous late Holocene lacustrine records are scarce in the Qaidam Basin， but is of especially important for our understanding the future climate variability in the western China. Here， we use grain size， element content and XRD-identified data from the lake Hurleg in the eastern Qaidam Basin to present the late Holocene climate variability， which have been temporally constrained using210Pb-，137Cs- and AMS14C dating. Our records demonstrate that decreased precipitation climate occurred at ～800-1000 yr and ～1300-1800 yr intervals， and increased precipitation occurred at ～354-800 yr，～1000-1300 yr and ～1800 yr to the present. The results show that the Qaidam Basin has undergone a process of warming and humidification since the Industrial Revolution， which is consistent with the meteorological records. The climate in the northeastern Qaidam Basin is dominated by the Asian monsoon.

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Insight into the Permeability and Microstructure Evolution Mechanism of the Sliding Zone Soil: A Case Study from the Huangtupo Landslide, Three Gorges Reservoir, China

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Journal of Earth Science 2024年第3期35卷 941-954页

作者： Qianyun Wang Huiming Tang Pengju An Kun Fang Junrong Zhang Minghao Miao Qingwen Tan Lei Huang Shengming Hu Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China Faculty of Engineering China University of GeosciencesWuhan 430074China Institute of Rock Mechanics Ningbo UniversityNingbo 315211China National and provincial Joint Engineering laboratory for the Hydraulic Engineering Safety and Efficient Utilization of water resources of poyang lake Basin Nanchang Institute of TechnologyNanchang 330099China

A large number of laboratory investigations related to the permeability have been conducted on the sliding *** little attention has been paid to the particular sliding zones of the slideprone Badong ***,we experimentally investigate the permeability nature and the mechanism of seepage in the viscous sliding zone of the Huangtupo *** seepage tests have been performed first with consideration of six dry densities and thirteen hydraulic gradients,in conjunction with the mercury intrusion porosimetry test and scanning electron microscopy test for the microstructure analysis after *** results show that seepage in the sliding zone soil does not follow Darcy’s Law,since there is a threshold hydraulic gradient(i0)below which no flow is observed and a critical hydraulic gradient(icr)over which the hydraulic conductivity(K)tends to be *** percentage of bound water could be responsible for the occurrence of i0 and ***,pore size distributions(PSD)less than 0.6µm and between 10 and 90µm exhibit positive and negative correlations with the i0,respectively,indicating that the i0 is related to the *** mechanism accounting for this result is that pore water pressure forces fine clay particles into the surrounding large pores and converts arranged particles to discretely distributed ones,thereby weakening the connectivity of *** seepages in the sliding zones behave differently from that in the sliding mass and sliding bed in response to the permeability.

关键词： reservoir landslides sliding zone soil permeability microstructure seepage.

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Distribution characteristics and indicative significance of grain size and elemental content in surface-sediments of Qinghai lake， Northeastern Tibetan Plateau

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Journal of Earth Science 2024年

作者： Yuqi Cheng Haicheng Wei Ronglei Duan Shun Wang Zhixiang Wang Hongyu Li Fangming Zeng Yilin Hou Hongpan Xue key laboratory of Green and High-end Utilization of Salt lake resources， Qinghai Institute of Salt lakes， Chinese Academy of Sciences Qinghai provincial key laboratory of Geology and environment of Salt lakes Qinghai Institute of Salt lakes， Chinese Academy of Sciences University of Chinese Academy of Sciences

Qinghai lake in the northeastern Qinghai-Tibet Plateau (QTP)， being sensitive to paleoclimate change and anthropogenic activities， has attracted much attention from paleoenvironmental researchers. Grain size and elemental content in lake sediments are indispensable proxies for reconstructing paleoclimate and paleoenvironment. However， limited research on grain size and elemental content of surface-sediments in Qinghai lake complicates decoding the information from lacustrine sedimentary strata. In this study， 55 surface-sediment samples were collected for grain size and elemental content analysis， combined with grain size end-member modeling algorithm (EMMA)， correlation (CA) and principal component (PCA) analysis to explore the controlling mechanisms and their environmental indications. Our results show that the hydrodynamic condition controls the distribution of surface-sediments in Qinghai lake: exhibiting a belt-like pattern of sand-silt-clay， the clockwise circulation in the northwestern and southwestern lake transports sand to the two primary sedimentary centers. Three primary components representing different transport/depositional processes were separated: ‘lacustro-aeolian’， ‘fluvio-aeolian’ and river-transported bedload. Grain size controls the elemental content， particularly in terrestrial particles. Nitrogen (N) and phosphorus (P)， mainly derived from endogenous organic matter (OM)， tend to be absorbed by finer particles. The hydrodynamic conditions and anthropogenic activities also influence their spatial distribution. The chemical weathering index (CIA)， indicating a cold and dry climate， is highly related to grain size. This research provides crucial modern process references for accurately interpreting grain size and element records in sediment cores from Qinghai lake.

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The GNSS PWV retrieval using non-observation meteorological parameters based on ERA5 and its relation with precipitation

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Geodesy and Geodynamics 2024年第3期15卷 302-313页

作者： Weifeng Yang Zhiping Chen Kaiyun Lv Pengfei Xia Tieding Lu School of Surveying and Geoinformation Engineering East China University of TechnologyNanchang 330013China key laboratory of Mine environmental Monitoring and Improving around poyang lake of Ministry of Natural resources East China University of TechnologyNanchang 330013China State key laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China jiangxi Province Engineering Research Center of Surveying Mapping and Geographic InformationNanchang 330025China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

The pressure and temperature significantly influence precipitable water vapor(PWV) retrieval. Global Navigation Satellite System(GNSS) PWV retrieval is limited because the GNSS stations lack meteorological sensors. First, this article evaluated the accuracy of pressure and temperature in 68 radiosonde stations in China based on ERA5 Reanalysis data from 2015 to 2019 and compared them with GPT3model. Then, the accuracy of pressure and temperature calculated by ERA5 were estimated in 5 representative IGS stations in China. And the PWV calculated by these meteorological parameters from ERA5(ERA5-PWV) were analyzed. Finally, the relation between ERA5-PWV and precipitation was deeply explored using wavelet coherence analysis in IGS stations. These results indicate that the accuracy of pressure and temperature of ERA5 is better than the GPT3 model. In radiosonde stations, the mean BIAS and MAE of pressure and temperature in ERA5 are-0.41/1.15 hpa and-0.97/2.12 K. And the mean RMSEs are 1.35 hpa and 2.87 K, which improve 74.77% and 40.58% compared with GPT3 model. The errors of pressure and temperature of ERA5 are smaller than the GPT3 model in bjfs, hksl and wuh2, and the accuracy of ERA5-PWV is improved by 18.77% compared with the GPT3 model. In addition, there is a significant positive correlation between ERA5-PWV and precipitation. And precipitation is always associated with the sharp rise of ERA5-PWV, which provides important references for rainfall prediction.

关键词： ERA5 GNSS Precipitable water vapor Precipitation Wavelet coherence analysis

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Flow variation and circulation process of saline springs in the Nangqen Basin， Tibetan Plateau

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Journal of Earth Science 2024年

作者： Jibin Han Jianping Wang Hongkui Ma Yongshou Li Zhao An Yong Xiao Wenhua Han Huaide Cheng Haizhou Ma Hongchen Jiang key laboratory of Green and High-end Utilization of Salt lake resources， Qinghai Institute of Salt lakes， Chinese Academy of Sciences Qinghai provincial key laboratory of Geology and environment of Salt lakes， Qinghai Institute of Salt lakes， Chinese Academy of Sciences Qinghai Geological Survey Faculty of Geosciences and Engineering， Southwest Jiaotong University State key laboratory of Biogeology and environmental Geology， China University of Geosciences

There was limited knowledge about the flow fluctuations and cycling processes of saline springs in the Nangqen Basin in the Sanjiang tectonic zone. In this work， the flow variation of the saline springs during the wet and dry seasons were monitored using volumetric and cross-sectional methods， and the cycling process of the saline springs was quantitatively identified using the integrated hydrochemical and isotopic methods. The results show that most saline springs in the Nangqen Basin had significantly different flow rates， ion concentrations， and TDS concentrations. The ions mainly come from carbonate and sulfate minerals. There is no internal hydraulic connection between these saline springs， and the impact of seasonal changes on the flow is relatively small， indicating that the saline springs originate mainly from deep circulation. The recharge elevation of the saline springs ranges 3661–4990 m， with an average of 4100 m. The circulation depth of the saline springs ranges 240–570 m， with an average of 431 m. The recycle time ranges 1.15–30.86 years， with an average of 15.66 years. These results could provide a scientific basis for the development and utilization of saline spring resources in the Nangqen Basin.

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Arbuscular mycorrhizal fungi-mediated resistance to salt spray in Cinnamomum camphora seedlings enhanced by leaf functional traits

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Soil Ecology Letters 2024年第3期6卷 163-175页

作者： Xiao Li Duo Zheng Naili Zhang Lijia Dong Aiping Wu Qiqian Wu Hua Liu Mingshui Zhao Yan Li Xinping Wang Yanhong Wang State key laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China State key laboratory of Efficient Production of Forest resources and the key laboratory of Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing 100083China School of Life and environmental Sciences Shaoxing UniversityShaoxing 312000China Ecology Department College of Environment and EcologyHunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake AreaHunan Agricultural UniversityChangsha 410128China Zhejiang Tianmu Mountain National Nature Reserve Administration Hangzhou 311311China

Salt spray is a natural disturbance in coastal *** mycorrhizal fungi(AMF)are recognized as bio-ameliorators of soil salinity in ***,the mechanism through which AMF protects Cinnamomum camphora against aerial salinity remains *** address this knowledge gap,plants were subjected to four fungal regimes,namely sterilized fungal inoculum,Glomus tortuosum,Funneliformis mosseae,or a combination of these two fungi,and exposed to three sprayed-salt regimes(0,7,or 14 mg NaCl cm−2 d−1)in a *** spray significantly decreased photosynthetic capabilities,total dry weight,and salinity tolerance of non-mycorrhizal *** inoculation,particularly a combination of *** and ***,evidently mitigated the detrimental effects induced by salt ***,mycorrhiza-mediated protection depended on the intensity of sprayed salt and the identity of fungal ***,the enhanced resistance of mycorrhizal *** seedlings to aerial salinity was mainly owing to increased leaf thickness and photosynthetic *** findings imply that inoculation with combined fungi could be an optimal strategy for cultivating *** plants in coastal *** results gained hold the potential to offer both theoretical and practical guidance for the managers of coastal ecosystems in soil restoration and conservation.

关键词： arbuscular mycorrhizal fungi leaf thickness photosynthetic capability salinity-tolerance salt spray

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