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Historical Sediment Record of ^(137)Cs, δ-HCH, and δ^(13)C Reflects the Impact of Land Use on Soil Erosion

Journal of Mountain Science 2014年第4期11卷 866-874页

作者： tang xiang-yu ZHANG Xin-Bao GUAN Zhuo LONG Yi tang Qiang Lü yu-Juan Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and Environment Chinese Academy of Sciences College of Water Resources and Architectural Engineering Northwest A&F University

This paper reports the concentrations of 137Cs, hexaehlorocyclohexane （HCH）, dichlorodiphenyltrichloroethanes （DDT） and its main degradation products, δ3C, and organic carbon in pond sediments （O-210 cm, sectioned by 2-20 cm interval） and surface soils （the 0-3 cm horizon） collected in 2OlO from Chenjia catchment, which is located in Yanting county in the hilly central Sichuan of China. α-, β-, and γ-HCH, DDT, and DDD were not detected throughout the sediment profile. Trace concentrations of δ-HCH （0.89-29.31 ng g^-1） and p,p＇- DDE （1.85-6.02 ng g^-1） were detected only in top 40 cm sediment. The 137Cs fallout peak in 1963 （corresponding to the 55-60 cm depth）, the sedimentary signature left by the last year of HCH use in 1989 （an additional indicator at 20-25 cm）, and the obvious original channel bed prior to the construction of the pond in 1956 were used as temporal markers to estimate changes in average sedimentation rate between different periods due to changes in land use. Continuous, marked decrease in average sedimentation rate （i.e., 3.79, 1.35 and 1.07 cm year-1 in 1956-1963, 1963-1989, and 1989-2010, respectively） over time was observed, probably due to the reforestation, abandoning of steep sloping farmland for afforestation and natural re-vegetation （implementation of the Grain for Green Program）, and the conversion of part of gently sloping farmlandterraces to orchard land since the 1980s, especially since the 1990s. This was corroborated by the observed decrease （more negative） in δ3C of sediment towards the surface, which indicates increased relative contribution of eroded soil particles coming from slopes with increased tree cover in sediment source area. Combined use of 137Cs, δ-HCH, and δ3C record in sediments has been demonstrated to be a powerful approach to reconstruction of response in sedimentation rate to historical land use changes.

关键词： Cesium-137 Hexaehlorocyclohexane(HCH) Sedimentation history Land use

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Spatial distribution of soil hydraulic parameters estimated by pedotransfer functions for the Jialing River Catchment,Southwestern China

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Journal of Mountain Science 2016年第1期13卷 29-45页

作者： LEI Wen-Juan tang xiang-yu Brian J.REID ZHOU xiang-Yang Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China School of Environmental Sciences University of East AngliaNorwich NR4 7T JUK College of Water Resource&Hydropower University of SichuanChengdu 610065China

Soil hydraulic parameters θs,α,n,Ks,L and θr of the van Genuchten-Mualem model were estimated using three pedotransfer functions(PTFs) based on soil properties for surface soils of the largest main tributary catchment(the Jialing River) of the upper Yangtze River in *** soil database was from the second national soil survey of China with a spatial 30 × 30 arc-second *** to the statistical analysis of the differences between the continuous-PTFs-estimated values of soil hydraulic parameters for the study catchment and the reference values for a specific texture class provided in the development database of a specific PTF,best estimations were obtained using the W?sten *** Rawls & Brakenssiek PTF was good estimation for parameter θr that was assumed as zero by W?sten *** established higher θr(0.08%) and lower Ks(20 cm/d) and θs(0.43%) in the mid-downstream area relative to the other areas of the catchment could lead to larger amounts of surface runoff andconsequently provide higher energy to erode ***,these factors provide a supporting explanation for previously reported severe soil erosion occurring in this *** heterogeneity analysis for estimated hydraulic parameters in terms of semivariogram showed that the spatial correlation distance was in the range of 50-80 km and that the spatial variability(sill) was not large except for parameters Ks and *** semi-variance with the exponential model at the zero distance(nugget) was 30%-50% of the *** study provided a practical PTF approach for estimating soil hydraulic properties from soil survey data at a large watershed *** estimation results could provide better insight into the mechanism of surface runoff and soil erosion,which is important to better understand and manage erosion in the catchment.

关键词： hydraulic catchment erosion downstream runoff texture exponential heterogeneity watershed fitted

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Spatial distribution of the oxygen-18 in precipitation in China based on a new empirical model

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Journal of Mountain Science 2019年第11期16卷 2605-2614页

作者： ZHAO Pei GUO Zheng-sheng SHE Dong-li tang xiang-yu Department of Geography Shangluo UniversityShangluo 726000China Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China College of Urban and Environment Sciences Shanxi Normal UniversityLinfen 041000China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Research Center of Soil and Water Conservation and Ecological EnvironmentChinese Academy of Sciences&Ministry of EducationYangling 712100China

Modeling the oxygen-18 in precipitation based on regional topography and meteorological factors is helpful to constrain missing isotopic data in some regions that is required for many paleoclimate,eco-hydrological and atmospheric circulation ***,the relationship betweenδ18Oin precipitation(δ18OPPT)and the affecting factors need to be thoroughly *** present a model considering the combined effects of temperature,altitude,and latitude on the spatial variability of annual average of stable isotopes in precipitation across *** new model performed significantly better(P<0.05)than the widely used Farquhar and Bowen&*** model allows modelling the spatial distribution of isotopes in precipitation depending on temperature *** residuals of presented model did not significantly correlate with *** on the model and residuals,a high-resolution map of annual averageδ18Opptacross China was generated.δ18OPPTdecreased from low toward high latitudes and from low towards high altitudes *** model application provides important information forancient climate,hydrological cycle and water vapor sources studies.

关键词： Climate change Isotope hydrology Geographic information Spatial distribution

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Identification of ^(137)Cs Reference Sites in Southeastern China

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Pedosphere 2006年第4期16卷 468-476页

作者： tang xiang-yu YANG Hao DU Ming-yuan ZHAO Qi-Guo LI Ren-Ying National Institute for Agro-Environmental Sciences Kannondai 3-1-3 Tsukuba Ibaraki 305-8604 （Japan） College of Geography Science Nanjing Normal University Nanjing 210097 Institute of Soil Science Chinese Academy of Sciences Nanjing 210008

The 137Cs vertical distributions in uncultivated and cultivated soils, developed from Quaternary red clay, granite, argillaceous shale, and red sandstone, were studied to develop reliable guidelines for selecting reference sites in southeastern China, which is dominated by strong acidic and/or clay-textured soils, and examine their reliability by comparing them to the reported 137Cs reference inventory data to see whether they agreed with the global distribution pattern. It was observed that a relatively high proportion of 137Cs was concentrated in the surface layers of soils with relatively high clay content. In the paddy soils developed from granite more 137Cs penetrated to depths below the plow layer (about 45.3%), when compared to those from the other three parent materials. The relatively low soil 137Cs inventories on crests excluded using the crest as the 137Cs reference site; instead the paddy field on the hillock plain was selected. Furthermore, within a specific county characterized by great systematic spatial variations of rainfall and topography across the landscape, a significant (P<0.01) and positive linear relationship (r2=0.81) between local 137Cs inventory and corresponding local annual rainfall was observed. Thus, for areas with large variations in rainfall, a single uniform value of local 137Cs reference inventory should be used with caution.

关键词： ^ 137CS inventory paddy field reference site southeastern China uncultivated soils

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A NUMERICAL STUDY ON THE PATH AND ORIGIN OF THE YELLOW SEA WARM CURRENT (YSWC)

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Journal of Hydrodynamics 2001年第3期13卷 1-9页

作者： Qiao Fang li, Xu Xiao biao, tang yu xiang, Zhao Wei Labortary of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 266061, China Labortary of Marine Science and Numerical Modeling State Oceanic Administration

A three dimensional baroclinic model (POM) is employed to study the path, orgin and strength of the Yellow Sea Warm Current (YSWC). The model produced results are compared with the observed temperature and salinity fields, the trajectories of drifters and moored current meter data. The results show: (1) It is indicated for the first time that the YSWC in winter orignates from the middle sector (28°N, 126°E), the truning directional sector (30°N, 127°E) of the Kuroshio in the East China Sea (ECS) and the separated sector of the Tsushima Warm Current (TsWC) at (31°N, 128°E), while in summer mainly originates from the Taiwan Warm Current (TaWC) and partly from the separated sector of the TsWC. This path is consistent with the main distribution feature of the quasi synoptic observed temperature and salinity. The model produced anticyclonic gyre (28°N, 125.5°E) branched from the middle sector of the ECS Kuroshio agrees with the observed results of the satellite drifters. (2) The model produced YSWC is located between 50～60m isobath on the West Side of the Yellow Sea Trough (YST), which is consistent with the location of the Warm and Saline tongue. The model produced cyclonic gyre centering at (36°N, 124.5°E) coincides with the observed results in Feb. 1997. The traditional view indicates that the Northern Jiangsu Coastal Current (NJCC) turns eastward at (32.5°N, 122°E). However, we think that the NJCC goes southward and only the coastal water invades near (32.5°N, 122°E). The model produced path is consistent with the warm tongue in the range of 34° 35°N, 122.5° 123.5°E in 30m layer. (3) The model produced YSWC is strong in winter and weak in summer, which coincides with the observations. The northward volume transport along 35°N section in winter and summer are 0.72sv and 0.38sv, respectively, with an annual flux of about 1.54·10 13 m 3. The volume transport entering the Bohai Sea in winter and summer are 0.19sv and 0.09sv, respectively, with an annual fl

关键词： POM YSWC Kuroshio

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坡耕地薄层紫色土-岩石系统中氮磷的迁移特征

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环境科学 2017年第7期38卷 2843-2849页

作者：鲜青松唐翔宇朱波中国科学院水利部成都山地灾害与环境研究所山地表生过程与生态调控重点实验室成都610041 中国科学院大学北京100049

于2015年两场代表性降雨事件下研究了紫色土坡耕地(1 500 m^2)水文过程驱动的氮磷地表和地下迁移特征.结果表明:(1)前期土壤水饱和度和降雨量决定地表径流和裂隙潜流的产流深度和胶体浓度的基本水平;降雨强度则控制产流量的变化趋势和... 详细信息

于2015年两场代表性降雨事件下研究了紫色土坡耕地(1 500 m^2)水文过程驱动的氮磷地表和地下迁移特征.结果表明:(1)前期土壤水饱和度和降雨量决定地表径流和裂隙潜流的产流深度和胶体浓度的基本水平;降雨强度则控制产流量的变化趋势和胶体浓度的峰值水平.(2)氮素主要以溶解态随裂隙潜流迁移;磷素则主要以细颗粒结合态通过地表径流流失.(3)氮磷迁移过程的水文驱动特征明显,氮素迁移主要受裂隙潜流的驱动作用影响,而磷素迁移则主要受地表径流的驱动作用影响.该研究结果丰富了对坡耕地薄层土壤-裂隙母岩二元系统中氮磷迁移对降雨响应规律的认识,可为农业氮磷非点源污染防治提供可靠的田间数据支持并明确关键的水文调控环节.

关键词：紫色土坡耕地径流过程胶体颗粒氮磷养分迁移

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紫色土丘陵区畜禽养殖场土壤中抗生素抗性基因分布特征

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环境科学 2019年第7期40卷 3257-3262页

作者：程建华唐翔宇刘琛中国科学院、水利部成都山地灾害与环境研究所山地表生过程与生态调控重点实验室成都610041 中国科学院大学北京100049

鉴于紫色土高垦殖丘陵区土壤中抗生素抗性基因的潜在生态环境风险,本研究采用高通量荧光定量PCR技术,分析了抗生素抗性基因在不同类型畜禽养殖场(养猪场、养鸡场和养牛场)土壤中的丰度和多样性.结果表明,3种养殖场土壤中共检出79种抗生... 详细信息

鉴于紫色土高垦殖丘陵区土壤中抗生素抗性基因的潜在生态环境风险,本研究采用高通量荧光定量PCR技术,分析了抗生素抗性基因在不同类型畜禽养殖场(养猪场、养鸡场和养牛场)土壤中的丰度和多样性.结果表明,3种养殖场土壤中共检出79种抗生素抗性基因和5种可移动基因元件,其中多重耐药类基因是养殖场土壤中丰度最高的耐药基因.不同养殖场土壤中抗生素抗性基因的丰度和多样性均表现为养鸡场和养猪场样品高于养牛场土壤,且3种养殖场土壤样品中的抗性基因表现出不同的类别分布特征.养殖场土壤中较高的可移动基因元件丰度,及其与抗生素抗性基因丰度显著的相关性(P<0.05)说明,可移动基因元件可能促进了抗生素抗性基因在养殖场土壤中的迁移和扩散.

关键词：紫色土畜禽养殖场抗生素抗性基因(ARGs) 可移动基因元件(MGEs) 高通量荧光定量PCR(HT-QPCR)

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高垦殖丘陵区不同类型农用地土壤中抗生素抗性基因分布特征

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环境科学 2023年第12期44卷 6947-6954页

作者：陈瑞程建华唐翔宇浙江农林大学林业与生物技术学院省部共建亚热带森林培育国家重点实验室杭州311300 中国科学院、水利部成都山地灾害与环境研究所山地表生过程与生态调控重点实验室成都610041

为揭示高垦殖丘陵区不同类型农用地土壤中抗生素抗性基因分布特征,分析了抗生素抗性基因在菜地、果园和耕地土壤中的丰度和多样性.结果表明,所有土壤样品中共检出70种抗生素抗性基因和4种可移动基因元件,其中β-内酰胺类cphA-01抗性基... 详细信息

为揭示高垦殖丘陵区不同类型农用地土壤中抗生素抗性基因分布特征,分析了抗生素抗性基因在菜地、果园和耕地土壤中的丰度和多样性.结果表明,所有土壤样品中共检出70种抗生素抗性基因和4种可移动基因元件,其中β-内酰胺类cphA-01抗性基因是农用地土壤中相对丰度最高的耐药基因.在菜地和果园土壤中,主要的抗性基因亚型为cphA-01和cmx(A),而耕地土壤以mexF和aacC基因为主.土壤中抗生素抗性基因的相对丰度和多样性均表现为:耕地<菜地<果园,这与不同农用地土壤的养分条件差异有关.类似地,土壤中可移动基因元件的相对丰度和多样性均以耕地土壤为最低,而其最高值分别出现在菜地和果园样品中.高垦殖丘陵区农用地土壤环境中可移动基因元件与抗生素抗性基因丰度呈显著正相关关系(P<0.05),表明基因水平迁移可能促进抗生素抗性基因在高垦殖丘陵区农用地土壤环境中扩散.

关键词：高垦殖丘陵区农用地抗生素抗性基因(ARGs) 可移动基因元件(MGEs) 高通量荧光定量PCR(HT-QPCR)

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抗生素在紫色土地表径流和地下渗流中的迁移

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中国环境科学 2022年第11期42卷 5328-5340页

作者：刘欣雨刘琛唐翔宇张建强西南交通大学地球科学与环境工程学院四川成都611756 中国科学院、水利部成都山地灾害与环境研究所四川成都610041 四川盐亭农田生态系统国家野外科学观测试验站四川绵阳621600

以川中丘陵区典型石灰性紫色土为对象,在生态养鸡果园管理模式下,探究不同种类粪源抗生素在连续自然降雨事件下随土壤水文过程的迁移浓度、通量及其对降雨的动态响应规律.结果表明,在蓄满产流机制下,连续强降雨导致地表径流和地下渗流... 详细信息

以川中丘陵区典型石灰性紫色土为对象,在生态养鸡果园管理模式下,探究不同种类粪源抗生素在连续自然降雨事件下随土壤水文过程的迁移浓度、通量及其对降雨的动态响应规律.结果表明,在蓄满产流机制下,连续强降雨导致地表径流和地下渗流中的抗生素浓度急剧增加.降雨过程中,抗生素浓度对降雨强度有明显响应,浓度峰与雨强峰一一对应,地下渗流的响应峰存在15~30min滞后.磺胺类抗生素在地表径流和地下渗流中的平均浓度分别高达1.22,4.07μg/L.在优先流作用下,吸附性较强的喹诺酮类和四环素类抗生素即使在降雨初期也能在地下渗流中被检出.地下渗流也是研究区紫色土中抗生素迁移的重要路径,其迁移总通量比地表径流高2个数量级.此外,鸡粪处理下抗生素迁移浓度和通量显著高于对照,表明粪源基质对污染物具有辅助运移作用.pH值和胶体浓度是主要影响因素,在降雨过程中的变化可引起抗生素形态及其与胶体结合作用改变.相关分析表明,胶体浓度与抗生素都呈正相关,pH值与磺胺类、四环素类抗生素和泰乐菌素呈显著正相关,而与氟苯尼考和喹诺酮类抗生素负相关.

关键词：抗生素紫色土迁移通量自然降雨地表径流地下渗流

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Effects and Mechanisms of P and K Nutrients on Yield and Protein Content of Fodder Rice

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Agricultural Sciences in China 2002年第4期1卷 432-437页

作者： tang xiang-ru and yu Tie-qiao( Department of Agronomy, South China Agricultural University, Guangzhou 510642 , P.R. China College of Plant Science and Technology, Hunan Agricultural University, Changsha 410128 , P.R. China) Department of Agronomy South China Agricultural University Guangzhou 510642 P. R. China College of Plant Science and Technology Hunan Agricultural University Changsha 410128 P.R. China College of Plant Science and Technology Hunan Agricultural University Changsha 410128 P.R. China

Effects and mechanisms of P and K nutrients on yield and protein content of Weiyou 56, a fodder hybrid rice combination,were studied through pot experiment and biochemical analysis. The results showed that the increase of P and K nutrients enhanced the activities of PEP carboxylase (PEPC), glutamine synthase (GS) and sucrose phosphate synthase (SPS) in leaves, sucrose synthase (SS), ADP glucose pyrophosphorylase (ADPGP) and GS in grains, and the chlorophyll content in leaves, soluble sugar and starch content in grains, protein N and total N content in leaves and grains. Howerer, they decreased soluble sugar content in leaves and led to an increase of protein content in brown rice, biomass, grain yield and harvest index. Excessive P nutrients slightly reduced SPS and ADPG activity in leaves and grains respectively.

关键词： Superphosphate Potassium chloride Fodder rice Yield Protein content Enzyme activity

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