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Variation in glomalin in soil profiles and its association with climatic conditions,shelterbelt characteristics,and soil properties in poplar shelterbelts of Northeast China 预览
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作者 Qiong Wang Wenjie Wang +2 位作者 Zhaoliang Zhong Huimei Wang Yujie Fu 《林业研究:英文版》 CAS CSCD 2020年第1期279-290,共12页
Glomalin-related soil protein(GRSP)sequesters large amounts of carbon and plays important roles in maintaining terrestrial soil ecosystem functions and ecological restoration;however,little is known about GRSP variati... Glomalin-related soil protein(GRSP)sequesters large amounts of carbon and plays important roles in maintaining terrestrial soil ecosystem functions and ecological restoration;however,little is known about GRSP variation in 1-m soil profiles and its association with stand characteristics,soil properties,and climatic conditions,hindering GRSP-related degraded soil improvement and GRSP evaluation.In this study,we sampled soils from 1-m profiles from poplar(Populus spp.)shelterbelts in Northeast China.GRSP contents were 1.8–2.0 times higher in the upper 40 cm soil layers than at 40–100 cm.GRSP-related soil organic carbon(SOC)sequestration in deeper soil layers was*1.2 times higher than in surface layers.The amounts of GRSP-related nutrients were similar throughout the soil profile.A redundancy analysis showed that in both surface and deeper layers,soil properties(pH,electrical conductivity,water,SOC,and soil nutrients)explained the majority of the GRSP variation(59.5–84.2%);the second-most-important factor in GRSP regulation was climatic conditions(temperature,precipitation,and altitude),while specific shelterbelt characteristics had negligible effects(<5%).Soil depth and climate indirectly affected GRSP features via soil properties,as manifested by structural equation model analysis.Our findings demonstrate that GRSP is important for carbon storage in deep soils,regardless of shelterbelt characteristics.Future glomalin assessments should consider these vertical patterns and possible regulating mechanisms that are related to soil properties and climatic changes. 展开更多
关键词 SOIL depth Glomalin-related SOIL protein(GRSP) SOIL organic carbon storage Climate change SOIL improvement
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Research Progress on the Effect of Biochar on Soil Organic Carbon 预览
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作者 Shuhong LIU 《农业生物技术:英文版》 CAS 2020年第2期79-81,共3页
Soil organic carbon has been identified as one of the most important components in soil.Changes in soil organic carbon content will significantly affect atmospheric CO2 concentration,which is related to soil fertility... Soil organic carbon has been identified as one of the most important components in soil.Changes in soil organic carbon content will significantly affect atmospheric CO2 concentration,which is related to soil fertility,water holding capacity,nutrient cycling,and changes in microbial communities.In recent years,biochar has been proven to be an effective material for increasing carbon storage,and research on the application of biochar in soil ecosystem carbon sequestration and emission reduction functions has received widespread attention.However,due to differences in the specific methods and research objects used in the research process,the current mechanism of the impact of biochar on soil organic carbon is still controversial.This paper mainly revealed the effects of biochar on soil organic carbon from the aspects of the effects of biochar addition on soil aggregates and microorganisms,and also elaborated on the direction worth exploring and objectively evaluated the impact mechanism of biochar on soil organic carbon. 展开更多
关键词 BIOCHAR Soil organic carbon Soil aggregate Soil microorganisms
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Method development for estimating soil organic carbon content in an alpine region using soil moisture data
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作者 Qi LUO Kun YANG +1 位作者 Yingying CHEN Xu ZHOU 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2020年第4期591-601,共11页
The high soil organic carbon(SOC) content in alpine meadow can significantly change soil hydrothermal properties and further affect the soil temperature and moisture as well as the surface water and energy budget. The... The high soil organic carbon(SOC) content in alpine meadow can significantly change soil hydrothermal properties and further affect the soil temperature and moisture as well as the surface water and energy budget. Therefore, this study first introduces a parameterization scheme to describe the effect of SOC content on soil hydraulic and thermal parameters in a land surface model(LSM), and then the SOC content is estimated by minimizing the difference between observed and simulated surface-layer soil moisture. The accuracy of the estimated SOC content was evaluated using in situ observation data at a soil moisture and temperature-measuring network in Naqu, central Tibetan Plateau. Sensitivity experiments show that the optimum time window for stabilizing the estimation results cannot be shorter than three years. In the experimental area, the estimated SOC content can generally reflect the spatial distribution of the measurements, with a root mean square error of 0.099 m~3 m~(-3), a mean bias of 0.043 m~3 m~(-3), and a correlation coefficient of 0.695. The estimated SOC content is not sensitive to the temporal frequency of the soil moisture data input. Even if the temporal frequency is as low as that of current soil moisture products derived from passive microwave satellites, the estimation result is still stable. Therefore, by combining a high-quality satellite soil moisture product and a parameter optimization method, it is possible to obtain grid-scale effective parameter values, such as SOC content,for an LSM and improve the simulation ability of the LSM. 展开更多
关键词 Land surface model Soil organic carbon content Soil porosity Soil parameter estimation
Effects of reduced nitrogen and suitable soil moisture on wheat(Triticum aestivum L.) rhizosphere soil microbiological,biochemical properties and yield in the Huanghuai Plain,China 预览
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作者 ZHOU Su-mei ZHANG Man +4 位作者 ZHANG Ke-ke YANG Xi-wen HE De-xian YIN Jun WANG Chen-yang 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第1期234-250,共17页
Soil management practices affect rhizosphere microorganisms and enzyme activities, which in turn influence soil ecosystem processes. The objective of this study was to explore the effects of different nitrogen applica... Soil management practices affect rhizosphere microorganisms and enzyme activities, which in turn influence soil ecosystem processes. The objective of this study was to explore the effects of different nitrogen application rates on wheat(Triticum aestivum L.) rhizosphere soil microorganisms and enzyme activities, and their temporal variations in relation to soil fertility under supplemental irrigation conditions in a fluvo-aquic region. For this, we established a split-plot experiment for two consecutive years(2014–2015 and 2015–2016) in the field with three levels of soil moisture: water deficit to no irrigation(W1), medium irrigation to(70±5)% of soil relative moisture after jointing stage(W2), and adequate irrigation to(80±5)% of soil relative moisture after jointing stage(W3);and three levels of nitrogen: 0 kg ha^–1(N1), 195 kg ha^–1(N2) and 270 kg ha^–1(N3). Results showed that irrigation and nitrogen application significantly increased rhizosphere microorganisms and enzyme activities. Soil microbiological properties showed different trends in response to N level;the highest values of bacteria, protease, catalase and phosphatase appeared in N2, while the highest levels of actinobacteria, fungi and urease were observed in N3. In addition, these items performed best under medium irrigation(W2) relative to W1 and W3;particularly the maximum microorganism(bacteria, actinobacteria and fungi) amounts appeared at W2, 5.37×10^7 and 6.35×10^7 CFUs g^–1 higher than those at W3 in 2014–2015 and 2015–2016, respectively;and these changes were similar in both growing seasons. Microbe-related parameters fluctuated over time but their seasonality did not hamper the irrigation and fertilization-induced effects. Further, the highest grain yields of 13 309.2 and 12 885.7 kg ha^–1 were both obtained at W2 N2 in 2014–2015 and 2015–2016, respectively. The selected properties, soil microorganisms and enzymes, were significantly correlated with wheat yield and proved to be valuable indicators of soil qualit 展开更多
关键词 suitable SOIL moisture nitrogen-reduction RHIZOSPHERE SOIL microorganisms RHIZOSPHERE SOIL enzyme activity winter wheat(Triticum AESTIVUM L.)
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土壤污染现状及治理措施 预览
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作者 沈颖辉 《云南化工》 CAS 2020年第1期150-152,共3页
阐述了土壤污染的特征、危害和现状,并从物理修复、化学修复和生物修复三方面简要介绍了土壤修复措施,旨在为土壤修复提供科学依据。
关键词 土壤污染 修复技术
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浅析土壤中氡浓度检测及其影响因素 预览
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作者 庞观华 《广东化工》 CAS 2020年第2期139-139,157共2页
氡气是一种无味无色的放射性气体,其如果存在人们的生活和工作环境中,会对人们的身体健康造成危害。相关调查结果表明,人如果长期接受高浓度的氡气照射,患肺癌的几率明显更高。因此,在建筑工程建设中,如果工程所在区域内的氡气的含量过... 氡气是一种无味无色的放射性气体,其如果存在人们的生活和工作环境中,会对人们的身体健康造成危害。相关调查结果表明,人如果长期接受高浓度的氡气照射,患肺癌的几率明显更高。因此,在建筑工程建设中,如果工程所在区域内的氡气的含量过高,则会造成建筑工程内低层内的氡浓度偏高,这会对人们的健康造成较为严重的影响。下面,首先介绍了检测土壤中氡浓度的方法及原则;其次,对检测土壤中氡浓度的实例分析进行了阐述;最后,总结了影响土壤中氡浓度检测质量的各项因素。 展开更多
关键词 土壤 氡气 干燥剂 土壤湿度
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Instrumental Characterization of Pretoria Clay Soil by XRF, XRD and SEM 预览
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作者 Adeyinka Olaseinde Mxolisi Brendon Shongwe +1 位作者 Joseph Babalola Adeshina Luqman Adisa 《矿物质和材料特性和工程(英文)》 2020年第1期1-8,共8页
The products of refractory materials are used for lining furnace, incinerators and kilns among other uses and they have the potential of withstanding high temperature without deformation. The objective of the research... The products of refractory materials are used for lining furnace, incinerators and kilns among other uses and they have the potential of withstanding high temperature without deformation. The objective of the research was to charac-terize the clay soil sample collected from Tshwane University of Technology in Pretoria. The sample, collected from a location Latitude 25.0969°S and Longi-tude 28.1624°E, was oven-dried, pulverized and sieved in the laboratory. Min-eralogical and elemental compositions of the sample were determined by using X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF) and Scanning Electron Microscopy (SEM) analytical methods. The XRF analysis revealed Fe2O3, Al2O3 and SiO2 as the major constituents, while the other elements occur in minor quantities. Mineralogically, the three samples contain Montmorillonite, Kaolinite and Bentonite, while Samples A contained Quartz in addition to ear-lier mentioned minerals, samples B and C contained Albite. 展开更多
关键词 CHARACTERIZATION Clay MINERALS Soil XRD XRF SEM
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Validation and correction of sea surface salinity retrieval from SMAP 预览
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作者 Sisi Qin Hui Wang +3 位作者 Jiang Zhu Liying Wan Yu Zhang Haoyun Wang 《海洋学报:英文版》 SCIE CAS CSCD 2020年第3期148-158,共11页
In this study, sea surface salinity(SSS) Level 3(L3) daily product derived from soil moisture active passive(SMAP)during the year 2016, was validated and compared with SSS daily products derived from soil Moisture and... In this study, sea surface salinity(SSS) Level 3(L3) daily product derived from soil moisture active passive(SMAP)during the year 2016, was validated and compared with SSS daily products derived from soil Moisture and ocean salinity(SMOS) and in-situ measurements. Generally, the root mean square error(RMSE) of the daily SSS products is larger along the coastal areas and at high latitudes and is smaller in the tropical regions and open oceans. Comparisons between the two types of daily satellite SSS product revealed that the RMSE was higher in the daily SMOS product than in the SMAP, whereas the bias of the daily SMOS was observed to be less than that of the SMAP when compared with Argo floats data. In addition, the latitude-dependent bias and RMSE of the SMAP SSS were found to be primarily influenced by the precipitation and the sea surface temperature(SST). Then, a regression analysis method which has adopted the precipitation and SST data was used to correct the larger bias of the daily SMAP product. It was confirmed that the corrected daily SMAP product could be used for assimilation in high-resolution forecast models, due to the fact that it was demonstrated to be unbiased and much closer to the in-situ measurements than the original uncorrected SMAP product. 展开更多
关键词 sea surface salinity(SSS) soil moisture active passive(SMAP) soil moisture and ocean salinity(SMOS) VALIDATION CORRECTION
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Wildfire effects on permafrost and soil moisture in spruce forests of Interior Alaska 预览
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作者 Christopher Potter Charles Hugny 《林业研究:英文版》 CAS CSCD 2020年第2期553-563,共11页
In the summer of 2015,hundreds of forest fires burned across the state of Alaska.Several uncontrolled wildfires near the town of Tanana on the Yukon River were responsible for the largest portion of the area burned st... In the summer of 2015,hundreds of forest fires burned across the state of Alaska.Several uncontrolled wildfires near the town of Tanana on the Yukon River were responsible for the largest portion of the area burned statewide.In July 2017,field measurements were carried out in both unburned and burned forested areas nearly adjacent to one another,all within 15 miles of the village of Tanana.These surveys were used to first visually verify locations of different burn severity classes,(low,moderate,or high),estimated in 2016 from Landsat images(collected before and after the 2015 Tanana-area wildfires).Surface and soil profile measurements to 30-cm depth at these same locations were collected for evidence of moss layer and forest biomass burning.Soil temperature and moisture content were measured to 30-cm depth,and depth to permafrost was estimated by excavation wherever necessary.Digital thermal infra-red images of the soil profiles were taken at each site location,and root-zone organic layer samples were extracted for further chemical analysis.Results supported the hypothesis that the loss of surface organic layers is a major factor determining post-fire soil water and temperature changes and the depth of permafrost thawing.In the most severely burned forest sites,complete consumption of the living moss organic layer was strongly associated with both warming at the surface layer and increases in soil water content,relative to unburned forest sites.Soil temperatures at both 10-cm and 30-cm depths at burned forest sites were higher by 8-10C compared to unburned sites.Below 15 cm,temperatures of unburned sites dropped gradually to frozen levels by 30 cm,while soil temperatures at burned sites remained above 5C to 30-cm depth.The water content measured at 3 cm at burned sites was commonly in excess of 30%by volume,compared to unburned sites.The strong correlation between burn index values and depth to permafrost measured across all sites sampled in July 2017 showed that the new ice-free profile in severely burned fo 展开更多
关键词 Alaska LANDSAT PERMAFROST RdNBR Soil temperature Soil water WILDFIRE
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Evaluation of soil flame disinfestation(SFD) for controlling weeds,nematodes and fungi 预览
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作者 WANG Xiao-ning CAO Ao-cheng +8 位作者 YAN Dong-dong WANG Qian HUANG Bin ZHU Jia-hong WANG Qiu-xia LI Yuan OUYANG Can-bin GUO Mei-xia WANG Qian 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第1期164-172,共9页
Soil flame disinfestation(SFD) is a form of physical disinfestation that can be used both in greenhouses and on field crops. Its use for soil disinfestation in different crop growing conditions makes it increasingly a... Soil flame disinfestation(SFD) is a form of physical disinfestation that can be used both in greenhouses and on field crops. Its use for soil disinfestation in different crop growing conditions makes it increasingly attractive for controlling soilborne pathogens and weeds. But little is known about the effect on weeds and soilbrone diseases. This study reports on greenhouses and field crops in China that determined the efficacy of SFD to control weeds, nematodes and fungi. It also determined the impact of SFD on the soil physical and chemical properties(water content, bulk density, NO3^–-N content, NH4^+-N content, conductivity and organic matter) in three field trials. A second generation SFD machine was used in these trials. SFD treatment significantly reduced weeds(>87.8%) and root-knot nematodes(Meloidogyne incognita)(>98.1%). Plant height and crop yield was significantly increased with SFD treatment. NO3^–-N and NH4^+-N increased after the SFD treatment, and there was also an increase in soil conductivity. Water content, bulk density and organic matter decreased significantly in the soil after the SFD treatment compared to the control. Soil flame disinfestation is a potential technique for controlling weeds and diseases in greenhouses or in fields. SFD is a non-chemical, safe, environmentally-friendly soil disinfection method. 展开更多
关键词 SOIL FLAME DISINFESTATION WEEDS PESTS control SOIL properties field application sustainable
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根系土在土壤环境研究中的应用 预览
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作者 田娜 彭秀红 《当代化工研究》 2020年第5期151-152,共2页
随着工农业生产的发展,土壤环境问题日益严峻,据2014年的《全国土地污染状况调查公报》显示,全国耕地土壤的超标率为19.4%,其中的主要污染物为镉、镍、铜、砷、汞、铅等重金属元素,重金属污染问题亟待解决。在土壤环境研究中,根系土作... 随着工农业生产的发展,土壤环境问题日益严峻,据2014年的《全国土地污染状况调查公报》显示,全国耕地土壤的超标率为19.4%,其中的主要污染物为镉、镍、铜、砷、汞、铅等重金属元素,重金属污染问题亟待解决。在土壤环境研究中,根系土作为一项重要的研究对象,对土壤环境研究尤其是农作物土壤具有重要意义。 展开更多
关键词 土壤 环境 根系土
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Research progress on the soil vapor extraction 预览
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作者 GUO Hao QIAN Yong +1 位作者 YUAN Guang-xiang WANG Chun-xiao 《地下水科学与工程:英文版》 2020年第1期57-66,共10页
Soil vapor extraction (SVE), the most common, efficient and economical means of remediation, is an in-situ remediation technique for removing volatile pollutants from unsaturated soil. The paper brie fly introduced th... Soil vapor extraction (SVE), the most common, efficient and economical means of remediation, is an in-situ remediation technique for removing volatile pollutants from unsaturated soil. The paper brie fly introduced the technological rationale and characteristics, summarized the theories and application research for SVE at home and abroad, and made the expectations and suggestions for the research on SVE. The international scholars have systematically researched the influence factors, remediation mechanism and numerical simulation of SVE. At present, SVE has been mostly integrated with other techniques to form enhanced SVE techniques, such as thermally enhanced SVE and AS-SVE (Air sparging- SVE), to be used for the field remediation widely. Compared with foreign countries, researches of Chinese scholars mainly focus on the laboratory research, especially on the influence factors, but rarely study the SVE model and the mass transfer mechanism of pollutant in SVE process. The SVE pilot studies are rare in China, and the field application has not been reported. In view of this situation, Chinese scholars in the future research can focus on the following aspects: (1) strengthening the research and systematized summary of SVE technical parameters and related knowledge;(2) strengthening the research on the mechanism and model of gas-phase mass transfer of pollutants in soil during SVE process;(3) strengthening the research on the enhanced SVE techniques and its application to actual site remediation. 展开更多
关键词 Soil vapor extraction(SVE) In situ remediation Organic pollution Soil remediation
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樟子松天然林土壤碳氮含量与水解酶活性坡位差异及月动态 预览
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作者 Vuong Thi Minh Dien 曾健勇 满秀玲 《林业科学》 EI CAS CSCD 北大核心 2020年第2期40-47,共8页
【目的】研究大兴安岭地区樟子松天然林土壤的碳氮含量与水解酶活性的坡位差异和月份动态,探究土壤碳氮含量与水解酶活性的关系,以期为阐明土壤碳氮转化酶学机制及森林土壤可持续利用提供理论依据。【方法】2018年5—10月每月中旬,在大... 【目的】研究大兴安岭地区樟子松天然林土壤的碳氮含量与水解酶活性的坡位差异和月份动态,探究土壤碳氮含量与水解酶活性的关系,以期为阐明土壤碳氮转化酶学机制及森林土壤可持续利用提供理论依据。【方法】2018年5—10月每月中旬,在大兴安岭漠河地区樟子松天然林坡地设置试验地。分别在试验地上、中、下坡位各设置3块20 m×30 m的樟子松林试验样地,每样地选3个取样点,每取样点清除枯枝落叶层后,记录不同土深(2.5、7.5、15、25 cm)处土壤温度。同时采集每个取样点不同土层(0~5、5~10、10~20和20~30 cm)的土壤样品测定土壤含水率、碳氮含量(有机碳、全氮)及水解酶(脲酶、蛋白酶、蔗糖酶、纤维素酶)活性。【结果】土壤的有机碳及全氮含量随土层加深而降低,随坡位升高而减少,但坡位差异不显著(P>0.05);0~5、5~10、10~20和20~30 cm土层的有机碳含量分别为68.53~80.38、40.28~46.66、15.86~21.08和11.91~13.79 g·kg-1,土壤全氮含量分别为5.34~5.96、2.98~3.68、2.35~2.61和1.54~1.75 g·kg-1;土壤脲酶、蛋白酶、蔗糖酶及纤维素酶活性随土层加深而降低;随坡位降低,土壤脲酶及蔗糖酶活性增高,蛋白酶与纤维素酶活性降低;月动态分析显示,土壤有机碳和全氮含量高峰期均为9月,酶活性高峰期集中在7—8月;相关分析表明,土壤碳氮(有机碳、全氮)含量与水解酶(脲酶、蔗糖酶、纤维素酶、蛋白酶)活性和含水率均极显著正相关(P<0.01),土壤温度与有机碳含量显著正相关(P>0.05)、与全氮含量显著负相关(P<0.05)。【结论】大兴安岭地区樟子松天然林土壤碳氮含量与水解酶活性随土层加深而降低,土壤碳氮含量与酶活性的坡位差异不显著(P>0.05),有机碳和全氮含量高峰期为9月,土壤水解酶活性高峰期集中在7—8月。土壤碳氮含量与水解酶活性极显著相关(P<0.01),土壤温湿度对碳氮含量与酶活性具� 展开更多
关键词 大兴安岭 樟子松 土壤 碳氮含量 水解酶活性 温湿度
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A 10-Yr Global Land Surface Reanalysis Interim Dataset(CRA-Interim/Land):Implementation and Preliminary Evaluation
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作者 Xiao LIANG Lipeng JIANG +3 位作者 Yang PAN Chunxiang SHI Zhiquan LIU Zijiang ZHOU 《气象学报:英文版》 SCIE CSCD 2020年第1期101-116,共16页
A land surface reanalysis dataset covering the most recent decades is able to provide temporally consistent initial conditions for weather and climate models,and thus is crucial to verifying/improving numerical weathe... A land surface reanalysis dataset covering the most recent decades is able to provide temporally consistent initial conditions for weather and climate models,and thus is crucial to verifying/improving numerical weather/climate forecasts/predictions.In this paper,we report the development of a 10-yr China Meteorological Administration(CMA)global Land surface ReAnalysis Interim dataset(CRA-Interim/Land;2007–2016,6-h intervals,approximately 34-km horizontal resolution).The dataset was produced and evaluated by using the Global Land Data Assimilation System(GLDAS)and NCEP Climate Forecast System Reanalysis(CFSR)global land surface reanalysis datasets,as well as in situ observations in China.The results show that the global spatial patterns and monthly variations of the CRA-Interim/Land,GLDAS,and CFSR climatology are highly consistent,while the soil moisture and temperature values of the CRA-Interim/Land dataset are in between those of the GLDAS and CFSR datasets.Compared with ground observations in China,CRA-Interim/Land soil moisture is comparable to or better than that of GLDAS and CFSR datasets for the 0–10-cm soil layer and has higher correlations and slightly lower root mean square errors(RMSE)for the 10–40-cm soil layer.However,CRA-Interim/Land shows negative biases in 10–40-cm soil moisture in Northeast China and north of central China.For ground temperature and the soil temperature in different layers,CRA-Interim/Land behaves better than the CFSR,especially in East and central China.CRA-Interim/Land has added value over the land components of CRA-Interim due to the introduction of global precipitation observations and improved soil/vegetation parameters.Therefore,this dataset is potentially a critical supplement to the CRA-Interim.Further evaluation of the CRA-Interim/Land,assimilation of near-surface atmospheric forcing variables,and extension of the current dataset to 40 yr(1979–2018)are in progress. 展开更多
关键词 GLOBAL LAND surface REANALYSIS DATASET CRA-Interim/Land ground temperature soil temperature soil moisture GLOBAL LAND Data Assimilation System(GLDAS)
林型和微立地类型及其土壤性质对土壤抗侵蚀能力的影响 预览
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作者 兰航宇 段文标 +3 位作者 陈立新 曲美学 王亚飞 赵戈榕 《水土保持学报》 CSCD 北大核心 2020年第2期108-114,共7页
采用原状土冲刷水槽法和静水崩解法测定土壤抗冲性和抗蚀性,以云冷杉红松林(PA)和椴树红松林(TP)的林隙和郁闭林分为对照,分析了小兴安岭地区2种林型由掘根倒木形成的不同丘和坑微立地类型及其土壤性质对土壤抗冲性和抗蚀性的影响,旨在... 采用原状土冲刷水槽法和静水崩解法测定土壤抗冲性和抗蚀性,以云冷杉红松林(PA)和椴树红松林(TP)的林隙和郁闭林分为对照,分析了小兴安岭地区2种林型由掘根倒木形成的不同丘和坑微立地类型及其土壤性质对土壤抗冲性和抗蚀性的影响,旨在揭示它们与土壤抗侵蚀能力的关系。结果表明:在2种林型下由掘根倒木形成的丘和坑微立地上,土壤砂粒含量均较高,其抗侵蚀能力均较弱,而对照却相反;2种林型下丘和坑微立地的土壤容重均与土壤抗冲性和抗蚀性呈无显著的负相关(P>0.05),而PA对照的土壤容重与它们均呈不显著正相关(P>0.05),TP林隙的土壤容重与它们却呈极显著正相关(P<0.01),其郁闭林分的土壤容重与它们呈极显著负相关;2种林型下丘和坑微立地的土壤有机质均与土壤抗冲性和抗蚀性呈不显著正相关,而对照则呈极显著正相关;土壤抗侵蚀能力随着林型和微立地类型而变化,TP丘和坑微立地的土壤抗侵蚀能力不显著高于PA,而PA对照的土壤抗侵蚀能力却显著高于TP的对照。由此可知,丘和坑微立地的形成会造成土壤抗侵蚀能力大幅下降,导致土壤养分的流失,土壤黏粒含量减少,土壤恢复过程较为困难。 展开更多
关键词 土壤 抗侵蚀能力 丘坑微立地 土壤性质
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Identification of potential electrotrophic microbial community in paddy soils by enrichment of microbial electrolysis cell biocathodes
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作者 Xiaomin Li Longjun Ding +2 位作者 Haiyan Yuan Xiaoming Li Yongguan Zhu 《环境科学学报:英文版》 SCIE EI CAS CSCD 2020年第1期411-420,共10页
Electrotrophs are microbes that can receive electrons directly from cathode in a microbial electrolysis cell(MEC).They not only participate in organic biosynthesis,but also be crucial in cathode-based bioremediation.H... Electrotrophs are microbes that can receive electrons directly from cathode in a microbial electrolysis cell(MEC).They not only participate in organic biosynthesis,but also be crucial in cathode-based bioremediation.However,little is known about the electrotrophic community in paddy soils.Here,the putative electrotrophs were enriched by cathodes of MECs constructed from five paddy soils with various properties using bicarbonate as an electron acceptor,and identified by 16S rRNA-gene based Illumina sequencing.The electrons were gradually consumed on the cathodes,and 25%–45% of which were recovered to reduce bicarbonate to acetic acid during MEC operation.Firmicutes was the dominant bacterial phylum on the cathodes,and Bacillus genus within this phylum was greatly enriched and was the most abundant population among the detected putative electrotrophs for almost all soils.Furthermore,several other members of Firmicutes and Proteobacteria may also participate in electrotrophic process in different soils.Soil pH,amorphous iron and electrical conductivity significantly influenced the putative electrotrophic bacterial community,which explained about 33.5% of the community structural variation.This study provides a basis for understanding the microbial diversity of putative electrotrophs in paddy soils,and highlights the importance of soil properties in shaping the community of putative electrotrophs. 展开更多
关键词 Electrotroph Paddy soil Microbial electrolysis cell Microbial community Soil property
Soil pressure and pore pressure for seismic design of tunnels revisited: considering water-saturated, poroelastic half-space 预览
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作者 Zhu Jun Liang Jianwen 《地震工程与工程振动:英文版》 SCIE EI CSCD 2020年第1期17-36,共20页
This paper describes a systematic study on the fundamental features of seismic soil pressure on underground tunnels, in terms of its magnitude and distribution, and further identifi es the dominant factors that signif... This paper describes a systematic study on the fundamental features of seismic soil pressure on underground tunnels, in terms of its magnitude and distribution, and further identifi es the dominant factors that signifi cantly infl uence the seismic soil pressure. A tunnel embedded in water-saturated poroelastic half-space is considered, with a large variety of model and excitation parameters. The primary features of both the total soil pressure and the pore pressure are investigated. Taking a circular tunnel as an example, the results are presented using a fi nite element-indirect boundary element(FE-IBE) method, which can account for dynamic soil-tunnel interaction and solid frame-pore water coupling. The effects of tunnel stiffness, tunnel buried depth and input motions on the seismic soil pressure and pore pressure are also examined. It is shown that the most crucial factors that dominate the magnitude and distribution of the soil pressure are the tunnel stiffness and dynamic soil-tunnel interaction. Moreover, the solid frame-pore water coupling has a prominent infl uence on the magnitude of the pore pressure. The fi ndings are benefi cial to obtain insight into the seismic soil pressure on underground tunnels, thus facilitating more accurate estimation of the seismic soil pressure. 展开更多
关键词 SEISMIC SOIL PRESSURE SEISMIC pore PRESSURE dynamic soil-tunnel interaction water-saturated POROELASTIC
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煤矿酸性废水对喀斯特稻田环境污染的实验研究 预览
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作者 王虎 吴永贵 +4 位作者 覃远翠 刘桂华 罗有发 付天岭 何照 《环境污染与防治》 CAS CSCD 北大核心 2020年第4期411-416,共6页
为系统评价煤矿酸性废水(AMD)污染对喀斯特稻田环境的影响,分析了不同程度AMD污染作用下稻田水-土体系中pH、电导率(EC)、氧化还原电位(Eh)、铁、锰、铜、锌、SO4^2-等特征污染组分及土壤微生物量、脲酶活性、磷酸酶活性、过氧化氢酶活... 为系统评价煤矿酸性废水(AMD)污染对喀斯特稻田环境的影响,分析了不同程度AMD污染作用下稻田水-土体系中pH、电导率(EC)、氧化还原电位(Eh)、铁、锰、铜、锌、SO4^2-等特征污染组分及土壤微生物量、脲酶活性、磷酸酶活性、过氧化氢酶活性等生物特性的变化。结果表明:(1)在污染前期较低污染倍数下,喀斯特稻田水-土系统对AMD污染有较好的缓冲性能,但高浓度持续污染1周以上可导致稻田田面水及土壤的明显酸化,增加体系的EC和Eh。(2)AMD的污染程度增加可提高田面水中铁、锰、铜、锌和SO4^2-;稻田土壤可通过吸附及自身的缓冲体系使得田面水中铁、锰、铜、锌较低,但在明显较高的污染程度下,又会通过土壤已有组分的溶出,明显增加田面水中锰、铜、锌。(3)AMD污染可降低稻田土壤微生物量、脲酶活性,但对磷酸酶活性的影响不明显;由于AMD引入大量H~+及丰富的铁离子将会促进H2O2的分解,进而造成过氧化氢酶活性总体升高的假阳性趋势。 展开更多
关键词 煤矿酸性废水 喀斯特稻田 土壤 酶活性
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微生物降解土壤中多环芳烃的研究进展 预览
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作者 吕鑫 孙延瑜 +2 位作者 闵军 胡晓珂 马莲菊 《安徽农业科学》 CAS 2020年第4期1-7,共7页
多环芳烃(polycyclic aromatic hydrocarbons,PAHs)在土壤中分布广泛且存留时间长。利用理化手段去除PAHs不仅价格昂贵,还会对土壤、沉积物以及地下水层等自然环境造成二次污染。生物修复主要是利用微生物代谢多样性降解有害污染物,被... 多环芳烃(polycyclic aromatic hydrocarbons,PAHs)在土壤中分布广泛且存留时间长。利用理化手段去除PAHs不仅价格昂贵,还会对土壤、沉积物以及地下水层等自然环境造成二次污染。生物修复主要是利用微生物代谢多样性降解有害污染物,被认为是最具有前景的修复技术。目前已分离鉴定出多种微生物具有降解PAHs的能力。为了更好地应用微生物修复土壤及环境中的PAHs污染,需要更加深入了解降解过程中微生物代谢途径的生理生化以及分子遗传机制。综述了土壤中多环芳烃的微生物降解,在前人研究的基础上,阐述了不同降解途径对不同分子量多环芳烃的生物代谢转化机理,为提高土壤中降解菌的生物修复能力提供了理论依据。 展开更多
关键词 多环芳烃 微生物降解 土壤
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有机肥对茶园土壤及茶叶产量与品质的影响研究进展 预览
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作者 尹荣秀 王文华 +3 位作者 郭灿 柳玲玲 周瑞荣 张邦喜 《茶叶通讯》 北大核心 2020年第1期6-12,共7页
施用有机肥是调控茶叶产量和品质最重要的措施之一。本文综述了近十年来施用有机肥对茶园土壤质量及茶叶产量与品质影响的研究进展,系统阐述了有机肥在提高茶园土壤物理性质、增加土壤矿质养分含量、缓解土壤酸化、促进土壤微生物生长... 施用有机肥是调控茶叶产量和品质最重要的措施之一。本文综述了近十年来施用有机肥对茶园土壤质量及茶叶产量与品质影响的研究进展,系统阐述了有机肥在提高茶园土壤物理性质、增加土壤矿质养分含量、缓解土壤酸化、促进土壤微生物生长和提高茶叶产量和品质方面的重要作用,指出了有机肥应用于茶园中可能引起的抗菌素与重金属等污染物富集的潜在危害,并对今后的研究方向进行了展望,以期为有机肥在茶园中的安全与高效利用提供科学参考。 展开更多
关键词 有机肥 茶叶 品质 产量 土壤 潜在危害
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