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Estimating distribution of water uptake with depth of winter wheat by hydrogen and oxygen stable isotopes under different irrigation depths 被引量:9
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作者 GUO Fei MA Juan-juan +3 位作者 ZHENG Li-jian SUN Xi-huan GUO Xiang-hong ZHANG Xue-lan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第4期891-906,共16页
Crop root system plays an important role in the water cycle of the soil-plant-atmosphere continuum. In this study, com- bined isotope techniques, root length density and root cell activity analysis were used to invest... Crop root system plays an important role in the water cycle of the soil-plant-atmosphere continuum. In this study, com- bined isotope techniques, root length density and root cell activity analysis were used to investigate the root water uptake mechanisms of winter wheat (Triticum aesfivum L.) under different irrigation depths in the North China Plain. Both direct inference approach and multisource linear mixing model were applied to estimate the distribution of water uptake with depth in six growing stages. Results showed that winter wheat under land surface irrigation treatment (Ts) mainly absorbed water from 10-20 cm soil layers in the wintering and green stages (66.9 and 72.0%, respectively); 0-20 cm (57.0%) in the jointing stage; 0-40 (15.3%) and 80-180 cm (58.1%) in the heading stage; 60-80 (13.2%) and 180-220 cm (35.5%) in the filling stage; and 0-40 (46.8%) and 80-100 cm (31.0%) in the ripening stage. Winter wheat under whole soil layers irrigation treatment (Tw) absorbed more water from deep soil layer than Ts in heading, filling and ripening stages. Moreover, root cell activity and root length density of winter wheat under TW were significantly greater than that of Ts in the three stages. We concluded that distribution of water uptake with depth was affected by the availability of water sources, the root length density and root cell activity. Implementation of the whole soil layers irrigation method can affect root system distribution and thereby increase water use from deeper soil and enhance water use efficiency. 展开更多
关键词 hydrogen and oxygen stable isotopes multisource linear mixing model winter wheat distribution of wateruptake with depth
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Variation of soil-plant-atmosphere continuum stable isotope and water source in Qinghai spruce forest of the eastern Qilian Mountains 被引量:1
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作者 ZHOU Jun-ju WANG Xue +9 位作者 MA Luo LUO Chu-yu TANG Hai-tao GUO Zhao-nan CHEN Jia-wei SHI Su-han SHI Wei WEI Wei ZHANG Dong-xia LIU Chun-fang 《Journal of Mountain Science》 SCIE CSCD 2023年第2期355-366,共12页
Understanding the hydrogen and oxygen stable isotope composition and characteristics of different water bodies in soil-plant-atmosphere continuum is of significance for revealing regional hydrological processes and wa... Understanding the hydrogen and oxygen stable isotope composition and characteristics of different water bodies in soil-plant-atmosphere continuum is of significance for revealing regional hydrological processes and water cycle mechanisms.In this study,we analyzed the stable isotopic composition,relationship and indicative significance of precipitation,soil water(0~100 cm depth)and xylem water of Qinghai spruce(Picea crassifolia)forest in the eastern Qilian Mountains,and explored the circulation process among different water bodies.The results show that the stable isotopes of precipitation vary greatly during the entire observation period.The values ofδ2H andδ^(18)O in the precipitation in the warm season are richer than those in the cold season,and the slope and intercept of local meteoric water line(LMWL,δ2H=6.79δ18O+7.13)are both smaller than global meteoric water line(GMWL,δ2H=8.17δ18O+10.56).The stable isotopes of soil water at different depths underwent different degrees of evaporative fractionation,and theδ18O andδ2H of shallow soil water varied greatly,while the deep soil water tended to be similar.The topsoil(0~10 cm)can respond quickly to precipitation,and the response of the deep soil has a time lag.In the whole growing season,0~30 cm and 60~100 cm soil water are the main water sources of Qinghai spruce.The water source of Qinghai spruce was from all soil layers in May and September,mainly from the shallow soil layer(0~30 cm)in August and October,and mainly from the deep soil layer(60~100 cm)in June and July. 展开更多
关键词 stable hydrogen isotope stable oxygen isotope Soil-plant-atmosphere continuum SPAC Plant water use IsoSource model
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Rare-earth and trace elements and hydrogen and oxygen isotopic compositions of Cretaceous kaolinitic sediments from the Lower Benue Trough, Nigeria: provenance and paleoclimatic significance 被引量:2
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作者 Anthony T.Bolarinwa Sunday O.Idakwo David L.Bish 《Acta Geochimica》 EI CAS CSCD 2019年第3期350-363,共14页
This study evaluated the Cretaceous(Campanian–Maastrichtian) kaolinitic sediments of the Ajali/Mamu and Enugu/Nkporo Formations from the Lower Benue Trough of Nigeria. A combined method of inductively coupled plasma... This study evaluated the Cretaceous(Campanian–Maastrichtian) kaolinitic sediments of the Ajali/Mamu and Enugu/Nkporo Formations from the Lower Benue Trough of Nigeria. A combined method of inductively coupled plasma–mass spectrometry and isotope ratio mass spectrometry was used to investigate trace and rareearth element geochemistry and hydrogen and oxygen isotopic compositions. These data were then used to infer the sediments' provenance and paleoclimatic conditions during their deposition. The sediments contained low concentrations of most trace elements, with the exceptions of Zr(651–1352 ppm), Ba(56–157 ppm), V(38–90 ppm),and Sr(15.1–59.6 ppm). Average values of Co and Ni were1.5 and 0.7 ppm, respectively. Trace and rare earth element values were lower than corresponding values for upper continental crust and Post-Archean Australian Shale, with the exception of Zr. The samples showed only slight light rare-earth enrichment and nearly flat heavy rare-earth depletion patterns, with negative Eu and Tm anomalies,typical of felsic sources. Geochemical parameters such as La/Sc, Th/Sc, and Th/Co ratios support that the kaolinitic sediments were derived from a felsic rock source, likely deposited in an oxic environment.^(18 )O values ranged from+ 15.4 to + 21.2% for the investigated samples, consistent with a residual material derived from chemicalweathering of felsic rock and redeposited in a sedimentary basin(typical values of + 19 to + 21.2%). While in the basin, the sediments experienced extended interactions with meteoric water enriched in d D and d16 O. However,the variation in d D and d16 O values for the investigated samples is attributed to the high temperature of formation(54–91 °C). The d D and d^(18 )O values suggest that the sediments, although obtained from different localities within the Lower Benue Trough, formed under similar hot,tropical climatic conditions. 展开更多
关键词 RARE-EARTH and trace elements oxygen/ hydrogen isotopic composition Kaolinitic SEDIMENTS LOWER Benue TROUGH NIGERIA
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Analysis of carbon and oxygen stable isotopes in carbonate rocks by the laser micro-sampling technique
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作者 ZHENG Ping WANG Lansheng +2 位作者 YANG Yi GAO Xi ZHANG Zhonghua 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2013年第2期235-240,共6页
The analysis of stable isotopes of carbon and oxygen in different carbonate rocks by the phosphoric acid method is not easier than that by the laser sampling method developed in recent years, which optically focuses l... The analysis of stable isotopes of carbon and oxygen in different carbonate rocks by the phosphoric acid method is not easier than that by the laser sampling method developed in recent years, which optically focuses laser beams with sufficient energy on a micro area of a thin section in a vacuum sample box via microscope. CO 2 produced by heating decomposition of carbonate was purified by the vacuum system, and the stable isotopic values of carbon and oxygen were calculated and analyzed on a mass spectrometer. This paper adopted the laser micro-sampling technique to analyze the stable isotopes of carbon and oxygen in dolomite, carbonate cement, stromatolite and different forms of dawsonite (donbassite). Results indicated that the laser micro-sampling method is effective in analyzing carbonate composition and could be a convincing proof for justification on carbonate composition analysis. 展开更多
关键词 氧稳定同位素 稳定同位素分析 激光束聚焦 碳酸盐岩 微取样技术 同位素质谱仪 碳酸盐胶结物 真空系统
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Carbon and Oxygen Isotopic Composition of Surface-Sediment Carbonate in Bosten Lake (Xinjiang,China) and its Controlling Factors 被引量:14
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作者 Steffen MISCHKE Alexander PROKOPENKO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第2期386-395,共10页
Bosten Lake is a mid-latitude lake with water mainly supplied by melting ice and snow in the Tianshan Mountains. The depositional environment of the lake is spatially not uniform due to the proximity of the major inle... Bosten Lake is a mid-latitude lake with water mainly supplied by melting ice and snow in the Tianshan Mountains. The depositional environment of the lake is spatially not uniform due to the proximity of the major inlet and the single outlet in the western part of the lake. The analytical results show that the carbon and oxygen isotopic composition of recent lake sediments is related to this specific lacustrine depositional environment and to the resulting carbonate mineralogy. In the southwestern lake region between the Kaidu River inlet and the Kongqi River outlet, carbon isotope composition (δ^13C) values of the carbonate sediment (-1‰ to -2‰) have no relation to the oxygen isotope composition of the carbonate (δ^18O) values (-7‰ to -8‰), with both isotopes showing a low variability. The carbonate content is low (〈20%). Carbonate minerals analyzed by X-ray diffraction are mainly composed of calcite, while aragonite was not recorded. The salinity of the lake water is low in the estuary region as a result of the Kaidu River inflow. In comparison, the carbon and oxygen isotope values are higher in the middle and eastern parts of the lake, with δ^13C values between approximately +0.5‰ and +3‰, and δ^18O values between -1‰ and -5‰. There is a moderate correlation between the stable oxygen and carbon isotopes, with a coefficient of correlation r of approximately 0.63. This implies that the lake water has a relatively short residence time. Carbonate minerals constitute calcite and aragonite in the middle and eastern region of the lake. Aragonite and Mg-calcite are formed at higher lake water salinity and temperatures, and larger evaporation effects. More saline lake water in the middle and eastern region of the lake and the enhanced isotopic equilibrium between water and atmospheric CO2 cause the correlating carbon and oxygen isotope values determined for aragonite and Mg-calcite. Evaporation and biological processes are the main reasons for the salinity and carbonate mineralogy influence of the surface-sediment carbonate in Bosten Lake. The lake water residence time and the CO2 exchange between the atmosphere and the water body control the carbon and oxygen isotope composition of the carbonate sediment. In addition, organic matter pollution and decomposition result in the abnormally low carbon isotope values of the lake surface-sediment carbonate. 展开更多
关键词 CARBONATE ARAGONITE calcite stable carbon and oxygen isotope composition Bosten Lake
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Stable isotopes of water as a tracer for revealing spatial and temporal characteristics of groundwater recharge surrounding Qinghai Lake,China
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作者 LI Dong-sheng CUI Bu-li +1 位作者 ZHAO Yun-duo ZUO Feng-lin 《Journal of Mountain Science》 SCIE CSCD 2022年第9期2611-2621,共11页
Studying spatial and temporal characteristics of regional groundwater recharge will guide the scientific management and sustainable development of regional water resources.This study investigated stable isotopes(δ^(1... Studying spatial and temporal characteristics of regional groundwater recharge will guide the scientific management and sustainable development of regional water resources.This study investigated stable isotopes(δ^(18)O and δ^(2) H)of precipitation,groundwater,river water and lake water during 2019-2020 in Qinghai Lake Basin to reveal the spatial and temporal characteristics of groundwater recharge.The local meteoric water line was simulated using ordinary least squares regression(δ^(2) H=7.80δ^(18)O+10.60).The local evaporation lines of the river water,lake water and groundwater were simulated asδ^(2) H=6.21δ^(18)O-0.72,δ^(2) H=5.73δ0-3.60 and δ^(2) H=6.59δ0+1.76,respectively.The δ^(2) H and δ^(18)O of river water and groundwater were in more depleted values due to the recharge by precipitation at high altitudes or precipitation effects,and theδ^(2) H andδ^(18)O of the lake water were in more enriched values because of evaporation.The relationship between the δ^(2) H and δ^(18)O of groundwater and river water was not significantly different,indicating a strong hydrological connection between the groundwater and river water surrounding Qinghai Lake.Additionally,the maximum values of δ^(18)O and the minimum values of lc-excess of groundwater in most regions were both in August,and the minimum values of δ^(18)O and the maximum values of lc-excess of groundwater in most regions were both in October.Therefore,the groundwater was recharged by soil water with strong evaporation in August and recharged by precipitation at high altitudes in October.The recharge rate of groundwater was relatively fast in areas with large slopes and large hydraulic gradients(e.g.,south of Qinghai Lake),and in areas with strong hydrological connections between the groundwater and river water(e.g.,the Buha River Valley).Those results can provide data support for protection and utilization of water resources in Qinghai Lake Basin,and provide reference for groundwater research in closed lake basins on the Qinghai-Tibet Plateau. 展开更多
关键词 Recharge of groundwater hydrogen and oxygen stable isotopes Line-conditioned excess Surface water and groundwater Qinghai Lake Basin
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Stable isotope techniques in plant water sources:a review 被引量:3
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作者 Qiu Yang HongLang Xiao +3 位作者 LiangJu Zhao MaoXian Zhou CaiZhi Li ShengKui Cao 《Research in Cold and Arid Regions》 2010年第2期112-122,共11页
关键词 hydrogen and oxygen stable isotope composition PLANT water sources arid region
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Application of Stable Isotope Tracing Technologies in Identification of Transformation among Waters in Sanjiang Plain,Northeast China 被引量:6
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作者 XU Yingying YAN Baixing +2 位作者 LUAN Zhaoqing ZHU Hui WANG Lixia 《Chinese Geographical Science》 SCIE CSCD 2013年第4期435-444,共10页
In order to investigate the transformation among the precipitation,groundwater,and surface water in the Sanjiang Plain,Northeast China,precipitation and groundwater samples which were collected at the meteorological s... In order to investigate the transformation among the precipitation,groundwater,and surface water in the Sanjiang Plain,Northeast China,precipitation and groundwater samples which were collected at the meteorological station of the Sanjiang Mire Wetland Experimental Station,Chinese Academy of Sciences and the surface water which collected from the Wolulan River were used to identify the transformation of three types of water.The isotope composition of different kinds of water sources were analyzed via stable isotope(deuterium and oxygen-18) investigation of natural water.The results show a clear seasonal difference in the stable isotopes in precipitation.During the cold half-year,the mean stable isotope in precipitation in the Sanjiang Plain reaches its minimum with the minimum temperature.The δ18O and δD values are high in the rainy season.In the Wolulan River,the evaporation is the highest in August and September.The volume of evaporation and the replenishment to the river is mostly same.The groundwater is recharged more by the direct infiltration of precipitation than by the river flow.The results of this study indicate that the water bodies in the Sanjiang Plain have close hydrologic relationships,and that the transformation among each water system frequently occurs. 展开更多
关键词 稳定同位素 中国科学院 三江平原 东北地区 同位素示踪 鉴定技术 水域 平均降水
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金沙江下游流域大气降水氢氧稳定同位素特征及水汽来源
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作者 金可 于江 +5 位作者 张乾柱 周火明 万丹 赵姹 胡月 吴颐杭 《长江科学院院报》 CSCD 北大核心 2024年第5期26-34,共9页
金沙江下游流域地处干热河谷气候影响区,大气降水对该区域水文循环至关重要。分析了金沙江下游流域降水稳定同位素组成的季节变化特征及其影响因素,结合同位素示踪和HYSPLIT模型探讨了流域大气降水水汽来源。结果表明:金沙江下游流域降... 金沙江下游流域地处干热河谷气候影响区,大气降水对该区域水文循环至关重要。分析了金沙江下游流域降水稳定同位素组成的季节变化特征及其影响因素,结合同位素示踪和HYSPLIT模型探讨了流域大气降水水汽来源。结果表明:金沙江下游流域降水δ^(2) H和δ^(18) O雨季偏负而旱季偏正,气温和降水量对同位素组成影响较大而高程效应不显著;流域大气降水线斜率和截距均低于全球和我国大气降水线,主要受到非平衡蒸发作用影响;流域大气降水水汽来源和昆明地区类似,雨季降水主要受到西南与南亚季风影响,旱季降水潜在来源为西风带或极地大陆气团。研究成果对金沙江下游区域水文循环具有重要指导意义。 展开更多
关键词 大气降水 氢氧稳定同位素组成 影响因素 水汽来源 金沙江下游流域
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塔什库尔干河流域河谷大气降水同位素特征与水汽输送路径
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作者 李晗薇 姚俊强 +2 位作者 容韬 张天洋 高雅洁 《干旱区研究》 CSCD 北大核心 2024年第3期399-410,共12页
利用塔什库尔干河流域河谷2018年9月—2020年5月的降水事件的大气降水同位素数据,以及流域河谷代表性气象站点温度、降水、相对湿度等气象资料,分析降水中δ^(18)O、δ^(2)H和氘盈余(d-excess)变化特征,探讨影响因素,并基于拉格朗日后... 利用塔什库尔干河流域河谷2018年9月—2020年5月的降水事件的大气降水同位素数据,以及流域河谷代表性气象站点温度、降水、相对湿度等气象资料,分析降水中δ^(18)O、δ^(2)H和氘盈余(d-excess)变化特征,探讨影响因素,并基于拉格朗日后向轨迹模型(HYSPLIT)追踪解析流域河谷大气降水的水汽输送路径。结果表明:(1)降水δ^(2)H、δ^(18)O值总体上呈现夏季富集、冬季贫化的季节变化特征,且具有显著的温度效应(1.33‰·℃^(-1)),但未见显著雨量效应;(2)局地大气降水线方程为δ^(2)H=7.63δ^(18)O-3.55,呈现出显著的干旱气候特征;(3)HYSPLIT模拟结果表明研究流域降水水汽主要受西风环流和局地水汽再循环影响,其中夏半年局地水汽蒸发占比54.09%,冬半年西方路径中较长距离输送占比45.53%。8月源自印度洋的水汽可绕过青藏高原到达研究区域。成果可为塔什库尔干河流域水资源管理和气候应对提供参考依据。 展开更多
关键词 氢氧稳定同位素 大气降水 水汽来源 塔什库尔干河谷
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盐度对水体蒸发氢氧稳定同位素分馏的影响
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作者 孙志倩 赵枫 +1 位作者 姬浩然 刘延锋 《安全与环境工程》 CAS CSCD 北大核心 2024年第2期239-247,300,共10页
干旱区强烈的蒸发作用导致地表水体和土壤水、浅层地下水中盐度不断升高,而盐分亦会导致蒸发强度降低,水体蒸发导致的氢氧稳定同位素分馏特征是确定蒸发量的有效手段,但目前水体蒸发过程中氢氧同位素分馏特征的研究主要集中于淡水和低... 干旱区强烈的蒸发作用导致地表水体和土壤水、浅层地下水中盐度不断升高,而盐分亦会导致蒸发强度降低,水体蒸发导致的氢氧稳定同位素分馏特征是确定蒸发量的有效手段,但目前水体蒸发过程中氢氧同位素分馏特征的研究主要集中于淡水和低矿化度盐水,为探求不同盐度对水体蒸发过程中的氢氧稳定同位素分馏的影响,开展浓度分别为0、10、20、50、100和200 g/L盐溶液的室内蒸发实验,比较纯水与不同浓度盐水蒸发过程中氢氧稳定同位素的差异,探究其分馏过程,定量评价盐度对水分蒸发分馏过程的影响。实验结果表明:蒸发量随着水体盐度的升高而呈指数形式降低;蒸发过程中,重同位素在水体中不断富集,0~200 g/L盐水中^(2)H、^(18)O和^(17)O的瑞利分馏系数分别在1.089~1.155、1.019~1.033和1.009~1.018之间,并呈现随着盐水浓度的增大瑞利分馏系数逐渐增加的趋势;纯水和盐水中的δ^(2)H-δ^(18)O、δ^(2)H-δ^(17)O和δ^(17)O-δ^(18)O之间均呈良好的线性关系,部分纯水与盐水的蒸发线之间存在比较显著的差异;不同浓度盐水中氘盈余随着剩余水体积比的减小而迅速降低,两者之间呈显著的线性关系,但直线斜率随着盐水浓度的增大而呈现先降低后增大的规律。 展开更多
关键词 水体蒸发 盐度 氢氧稳定同位素 分馏
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百脉泉泉群泉水氢氧稳定同位素时空变化特征
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作者 王雅璇 肖蓓 +3 位作者 崔步礼 臧婧杰 郁万鑫 宗荷花 《地球环境学报》 CSCD 2024年第1期69-77,共9页
研究泉水氢氧稳定同位素时空变化特征,探究泉水的补给来源,对水资源管理及旅游业可持续发展具有重要指导意义。以百脉泉泉群为研究区,通过分析降水及泉水中的氢氧稳定同位素特征,获取了本地大气降水线、泉水同位素时空变化特征及蒸发线... 研究泉水氢氧稳定同位素时空变化特征,探究泉水的补给来源,对水资源管理及旅游业可持续发展具有重要指导意义。以百脉泉泉群为研究区,通过分析降水及泉水中的氢氧稳定同位素特征,获取了本地大气降水线、泉水同位素时空变化特征及蒸发线,并探究了百脉泉泉水的补给来源。结果表明:大气降水中δ2H的波动范围为-151.55‰δ18O—-4.28‰,δ18O的波动范围为-19.93‰δ18O—-0.52‰,δ2H和δ18O在时间上的分布规律相似,均呈现双峰状(“M”型),本地大气降水线(LMWL)为:δ2H=7.58×δ18O+4.17。百脉泉泉水的δ2H的波动范围为-65.23‰δ18O—-37.01‰,δ18O的波动范围为-8.99‰δ18O—-4.04‰。泉水δ2H—δ18O均落在本地大气降水线上或附近,泉水同位素蒸发线(LEL)为δ2H=5.75×δ18O-δ18O13.23,斜率(5.75)小于本地大气降水线斜率(7.58),表明泉水的补给来源主要为大气降水,且在入渗之前经历了较弱的蒸发作用。各泉泉水的补给区海拔均高于298 m,补给高程呈现百脉泉和东麻湾>墨泉和梅花泉>筛子泉和龙湾泉。且因地形、地层、岩性及降水量和持续时间等因素的制约,泉水同位素值及喷涌量的变化滞后于降水,降水至泉水喷涌时的补给周期尚需进一步结合同位素定年及水文地质条件厘定。相关研究结果将为百脉泉泉水资源合理利用及泉域旅游业的可持续发展提供借鉴。 展开更多
关键词 氢氧稳定同位素 本地大气降水线 蒸发线 补给来源 百脉泉泉群
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基于氢氧稳定同位素的地下水循环研究进展
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作者 刘闻明 李征 《黑龙江环境通报》 2024年第1期13-15,共3页
本文简单介绍了氢氧同位素在水文学中的研究进展,氢氧稳定同位素的分馏过程研究和氢氧稳定同位素示踪下水体间水力联系的探究,为氢氧稳定同位素在地下水循环过程提供了研究基础。
关键词 地下水循环 氢氧稳定同位素 端元混合模型 瑞利平衡分馏方程
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Plant water use strategies in the Shapotou artificial sand-fixed vegetation of the southeastern margin of the Tengger Desert, northwestern China 被引量:3
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作者 ZHAO Liang-ju WANG Xiao-gang +3 位作者 ZHANG Yu-cui XIE Cong LIU Quan-yu MENG Fei 《Journal of Mountain Science》 SCIE CSCD 2019年第4期898-908,共11页
Stable oxygen and hydrogen isotopic compositions(δ^(18)O and δD) of plant xylem water and its potential water sources can provide new information for studying water sources, competitive interactions and water use pa... Stable oxygen and hydrogen isotopic compositions(δ^(18)O and δD) of plant xylem water and its potential water sources can provide new information for studying water sources, competitive interactions and water use patterns of plants. The contributions of different water sources to three plants, Hedysarum scoparium(HS), Caragana Korshinskii(CK) and Artemisia ordosica(AO), were investigated in the artificial sand-fixed vegetation of Shapotou, the southeastern margin of the Tengger Desert of northwestern China, based on meteorological data and δ^(18)O and δD values of precipitation, groundwater, soil water and xylem water of HS, CK and AO. Our results indicated that soil water infiltration through precipitation was the main water source of the artificial sand-fixed vegetation. Obvious differences in soil water content and in δ^(18)O of soil water and xylem water were found among different seasons. No relationship was found between the δ^(18)O in plant xylem water and in soil water in January. The same water use patterns were found in CK, HS and AO in May, suggesting they have the same water sources. The different water sources of CK, HS and AO in August indicate that water competition occurred. In addition, the main water sources of CK, HS and AO in August mainly come from shallow soil water, while they use relatively deep soil water in May. This phenomenon is related to the differences of soil water content throughout soil profile, precipitation, transpiration and water competition under different growth periods. The water use patterns of CK, HS and AO respond to soil water content throughout the soil profile and their competition balance for water uptake during different growth season. The results indicate that these sandfixed plants have developed into a relatively stable stage and they are able to regulate their water use behavior as a response to the environmental conditions, which reinforces the effectiveness of plantation of native shrubs without irrigation in degraded areas. 展开更多
关键词 PLANT water source stable hydrogen and oxygen isotopeS Artificial and sand-fixed VEGETATION in Shapotou
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Isotopic evidence for the moisture origin and influencing factors at Urumqi Glacier No.1 in upstream Urumqi River Basin, eastern Tianshan Mountains 被引量:2
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作者 SONG Meng-yuan LI Zhong-qin +2 位作者 XIA Dun-sheng JIN Shuang ZHANG Xin 《Journal of Mountain Science》 SCIE CSCD 2019年第8期1802-1815,共14页
The stable isotope has been extensively applied as an effective tracer especially in precipitation. In glacierized area of arid northwest China, temperature is widely considered to be a major factor affecting isotopes... The stable isotope has been extensively applied as an effective tracer especially in precipitation. In glacierized area of arid northwest China, temperature is widely considered to be a major factor affecting isotopes in precipitation, while the influences of precipitation amount, relative humidity and other meteorological parameters are still not clear. Based on analyses on stable isotope values of water samples and NCEP/NCAR(National Centers of Environmental Prediction/National Center for Atmospheric Research, USA) re-analysis data, the moisture source and characteristics of isotopes in the precipitation, meltwater and river water isotopes at Urumqi Glacier No.1 of the upstream Urumqi River Basin, eastern Tianshan Mountains from spring to autumn during four years(from 2008 to 2011) was studied. Results indicated that meltwater are the main source of water for the upper Urumqi River. Seasonal variation of δ18 O in precipitation demonstrated that δ18 O was more enriched in summer and depleted in spring and autumn. Temperature was positively correlated with isotopes, while precipitation amount and relative humidity was negatively correlated with isotopes. The water vapor was affected by westerly air mass and regional water vapor cycle. Meanwhile, back trajectory clustering analyses showed that the moisture mainly from Europe and central Asia. The moisture was more likely to be locally sourced with the ratio was 46.8%~52.1%. 展开更多
关键词 stable hydrogen and oxygen isotope MOISTURE ORIGIN Precipitation URUMQI River Basin NORTHWESTERN China
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Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling
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作者 Shuang-Biao Han Chao-Han Xiang +3 位作者 Xin Du Lin-Feng Xie Jie Huang Cheng-Shan Wang 《Petroleum Science》 SCIE EI CAS 2024年第2期741-751,共11页
The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantl... The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas. 展开更多
关键词 Gas compositions stable isotopes Gas origins hydrogen gas Songliao Basin
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Isotopic Composition of Dissolved Carbonates Meromictic Soda Lake Doroninskoe(Eastern Transbaikalia,Russia) 被引量:1
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作者 Leonid V.ZAMANA Svetlana V.BORZENKO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期395-397,共3页
1 Introduction Meromictic soda Lake Doroninskoe localized in the intermountain area,filled with continental sediments of the Mesozoic,in the upper basin of the river Amur.Coordinates of its location are N51°14’4... 1 Introduction Meromictic soda Lake Doroninskoe localized in the intermountain area,filled with continental sediments of the Mesozoic,in the upper basin of the river Amur.Coordinates of its location are N51°14’42"E112°14’40", 展开更多
关键词 Soda lake dissolved carbonates sulfate reduction hydrogen sulfide isotopic composition carbon oxygen
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Water sources of plants and groundwater in typical ecosystems in the lower reaches of the Heihe River Basin
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作者 YunFeng Ruan LiangJu Zhao +3 位作者 HongLang Xiao GuoDong Cheng MaoXian Zhou Fang Wang 《Research in Cold and Arid Regions》 CSCD 2014年第3期226-235,共10页
Stable oxygen and hydrogen isotopic compositions (δ18O and δD) of soil water and shallow groundwater of a riparian forest, an artificial shrub forest, and Gobi of the lower reaches of the Heihe River Basin are use... Stable oxygen and hydrogen isotopic compositions (δ18O and δD) of soil water and shallow groundwater of a riparian forest, an artificial shrub forest, and Gobi of the lower reaches of the Heihe River Basin are used to study the recharge water sources of those ecosystems. IsoSource software is used to determine the δ180 values for root water of Populous euphratica and Tamarix ramosissima in the riparian forest ecosystem, Haloxylon ammodendron in the artificial shrub forest, and Reaumuria soongorica in the Gobi, as well as for local soil water and groundwater, and precipitation in the upper reaches of the Heihe River Basin. Our results showed that soil water and shallow groundwater of the riparian forest and the artificial shrub forest were recharged by river water which originated from precipitation in the upper reaches, and strong evaporation occurred in the artificial shrub forest. Soil water of the Gobi was not affected by Heihe River water due to this area being far away from the river channel. The main water sources of Populous euphratica were from 40-60-cm soil water and groundwater, and of Tamarix ramosissima were from 40-80-cm soil water in the riparian forest ecosystem. In the artificial forest, Haloxylon ammodendron used 200-cm saturated-layer soil water and shallow groundwater. The Reaumuria soongorica mainly used soil water from the 175-200-cm depth in the Gobi. Therefore, soil water and groundwater are the main water sources which maintain survival and growth of the plants in the extremely arid regions of the lower reaches of the Heihe River Basin. 展开更多
关键词 stable hydrogen and oxygen isotope composition (δD and δa80) extremely arid regions lower reaches of theHeihe River Basin plant water sources
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不同灌溉方式氢、氧同位素分布与夏玉米水分利用特征 被引量:3
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作者 杨永辉 邬佳宾 +4 位作者 武继承 杨先明 高翠民 潘晓莹 何方 《节水灌溉》 北大核心 2023年第1期71-77,85,共8页
利用氢氧稳定同位素示踪法,研究了人工控水条件下小白龙常规灌溉(X)与滴灌(D)不同灌水量(X1、D1:15 mm;X2、D2:30 mm;X3、D3:45 mm)夏玉米土壤水稳定同位素分布特征,以及土壤耗水量、光合作用及水分利用特征。结果表明:随生育期的推进,... 利用氢氧稳定同位素示踪法,研究了人工控水条件下小白龙常规灌溉(X)与滴灌(D)不同灌水量(X1、D1:15 mm;X2、D2:30 mm;X3、D3:45 mm)夏玉米土壤水稳定同位素分布特征,以及土壤耗水量、光合作用及水分利用特征。结果表明:随生育期的推进,根系吸水逐渐加深。在拔节期,均以0~20 cm土层的水分贡献率最大,达60%以上。在D1和D2条件下,60~80 cm和20~40 cm土层的贡献率分别占21.4%和23.8%。到灌浆期,与常规灌溉相比,滴灌条件下更利于促进根系对40 cm以下土层水分的利用,从而减少水分的无效蒸发。随生育期的推进与灌水量的增加,玉米的日耗水量明显增加,滴灌低于传统灌溉。与常规灌溉相比,滴灌D2处理更利于提高玉米光合速率、蒸腾速率、气孔导度及叶片水分利用效率。此外,滴灌处理明显提高了收获期玉米的生物量。最终,与常规灌溉相比,滴灌降低了玉米总的耗水量,产量提高了5.3%~21.7%和水分利用效率提高了9.2%~26.8%,均以D2处理最高。相关分析表明:玉米拔节期20~40 cm和灌浆期60~80 cm土层水分更利于促进玉米产量的提高,而拔节期60~80 cm和80~100 cm土层的水分更利于促进玉米水分利用效率的提高。 展开更多
关键词 滴灌 灌溉方式 控制灌水 稳定氢氧同位素 水分贡献率 水分运移 夏玉米 水分利用效率
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Study on Change Rules and Influencing Factors of Soil Moisture in Huaibei Plain
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作者 Lingjian KONG Zhenlong WANG +1 位作者 Bing WANG Lei WANG 《Asian Agricultural Research》 2021年第5期14-18,共5页
[Objectives]To study the relationship between soil water,groundwater burial depth,and precipitation for summer maize in Huaibei Plain.[Methods]The atmospheric precipitation,soil water and groundwater for the growth pe... [Objectives]To study the relationship between soil water,groundwater burial depth,and precipitation for summer maize in Huaibei Plain.[Methods]The atmospheric precipitation,soil water and groundwater for the growth period of summer maize in Huaibei Plain were analyzed using the 26-year long series of data from the Wudaogou Hydrological Experimental Station,combined with the hydrogen and oxygen stable isotope tracing method.[Results]The average soil moisture content of summer maize in different growth periods showed a trend of first decreasing,then increasing and then decreasing with the increase of soil depth.The average soil moisture content was the lowest at the surface soil layer.From the characteristic values of hydrogen and oxygen isotopes of atmospheric precipitation,soil water and groundwater,it can be known that the average values ofδ18O andδD of soil water decreased with the increase of soil depth,indicating that soil moisture evaporation leads to the enrichment of soil heavy isotopes,and the degree of enrichment decreased from the surface layer to the deep layer of the soil.The seasonal variation of the stable isotope of hydrogen and oxygen in soil water declined with the increase of soil depth.The soil water changes at 30 cm and 50 cm soil depths were the most obvious.The soil was easily recharged by precipitation,and soil evaporation was relatively strong.[Conclusions]The research results are favorable for in-depth understanding of the regional water cycle process,and are expected to provide a certain scientific basis for realizing the efficient and sustainable use of regional groundwater. 展开更多
关键词 Soil water PRECIPITATION Huaibei Plain hydrogen and oxygen stable isotopes
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