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基施与叶面施硒肥对富硒镉污染农田水稻降镉增硒的效应

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农业环境科学学报 2024年第5期43卷 974-982页

作者：郑晶鲍广灵陶荣浩吴承龙马友华叶文玲农田生态保育与污染防控安徽省重点实验室安徽农业大学资源与环境学院合肥230031 石台富硒农业试验站石台县农业农村局安徽池州245100

为探讨基施硒肥和叶面施硒肥在轻度镉污染的富硒土壤中对水稻降镉增硒的效果,在田间试验条件下,通过设置基施硒肥、叶面施硒肥和基施硒肥+叶面施硒肥3个处理,以常规施肥作为对照,对成熟期水稻产量、各部位镉和硒含量、富集与转运系数以... 详细信息

为探讨基施硒肥和叶面施硒肥在轻度镉污染的富硒土壤中对水稻降镉增硒的效果,在田间试验条件下,通过设置基施硒肥、叶面施硒肥和基施硒肥+叶面施硒肥3个处理,以常规施肥作为对照,对成熟期水稻产量、各部位镉和硒含量、富集与转运系数以及土壤中镉的形态进行测定分析。结果表明:叶面施硒肥能显著提高水稻产量。基施硒肥后,土壤pH提高了0.1.个单位,提高率为3.01.,同时降低了土壤中镉的弱酸提取态含量,降低率为2.96%,促进了镉从弱酸提取态向可氧化态和残渣态转变,从而降低了土壤中镉的有效性。而叶面施硒肥能显著降低水稻对镉转运特别是秸秆到糙米的转运系数,降低率达1..1.%,同时提高水稻对硒的转运特别是根到秸秆的转运系数,提高率达1..69%。不同硒肥处理下,糙米中镉含量为0.1.9~0.1.3 mg·kg^(-1.,硒含量为0.21.~0.244 mg·kg^(-1.,不同硒肥处理均能使糙米达到降镉增硒的效果,且叶面施硒肥处理相较于基施硒肥处理的效果更好,并在基施硒肥和叶面施硒肥同时使用下的效果最佳,其对糙米中镉含量的降低率达26.39%,硒含量的提升率达41.50%。综上,在轻度镉污染的富硒土壤中,基施硒肥或叶面施硒肥均能有效降低水稻籽粒中镉含量并提高稻米对硒的富集,且基施硒肥+叶面施硒肥处理是降低糙米镉含量与提高糙米硒含量综合效果最好的一种措施。

关键词：水稻硒肥镉转运和累积

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巢湖西半湖北岸湖滨带蓝藻堆积处细菌多样性初步研究

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水产学报 2011年第12期35卷 1873-1880页

作者：宣淮翔安树青孙庆业刘梅安徽大学资源与环境工程学院南京大学生命科学学院

采用限制性片段长度多态性(restriction fragment length polymorphism,RFLP)方法,研究了巢湖西半湖北岸湖滨带蓝藻堆积处不同深度层次的细菌多样性。利用直接法提取了蓝藻堆积处3个不同深度层次样品(A层0～2 cm、B层2～1. cm、C层1.～2... 详细信息

采用限制性片段长度多态性(restriction fragment length polymorphism,RFLP)方法,研究了巢湖西半湖北岸湖滨带蓝藻堆积处不同深度层次的细菌多样性。利用直接法提取了蓝藻堆积处3个不同深度层次样品(A层0～2 cm、B层2～1. cm、C层1.～20 cm)中的细菌总DNA,并进一步构建各层细菌的1.S rDNA克隆文库。结果表明,蓝藻堆积处各层细菌的margalef丰富度指数(dma)、Shannon-Wiener指数(H)和Simpson指数(D)均伴随深度的增加而减小。系统发育树分析显示,各层的细菌优势类群主要归属于厚壁菌门(Firmicutes)和变形菌门(Proteobacteria);且随深度层次的增加,归属于变形菌门的细菌比例减少,而归属于厚壁菌门的细菌比例增加;在A层样品中存在少量归属于蓝藻门(Cyanobacteria)、放线菌门(Actinobacteria)、浮霉菌门(Planctomycetes)、螺旋体门(Spirochaetes)类群的细菌;在C层样品中也存在少量归属于拟杆菌门(Bacteroidetes)类群的细菌。研究结果在一定程度上揭示了蓝藻堆积腐烂过程中细菌多样性和种类组成的变化。

关键词：蓝藻堆积处细菌多样性限制性片段长度多态性巢湖西半湖北岸湖滨带

The Statistical Analysis of Migration of Strong Earthquakes─Taking the North china Region as an Example

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Earthquake Research Advances 2004年第2期 77-86页

作者： Qin Chengzhi 1., Zhou Chenghu 1., Pei tao 1. and Li Quanlin 2) 1.State Key Laboratory of {1. and environmental Information System, Institute of Geographic Sciences and Natural {1. Research, CAS, Beijing 1.01.1. china 2)Institute of Geophysics, CEA, Beijing 1.0081. china State Key Laboratory of resources and {1. Information System Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Institute of Geophysics CEA Beijing 100081 China

The migration of strong earthquakes is an important research topic because the migration phenomena reflect partly the seismic mechanism and involve the prediction of tendency of seismic activity. Research on migration of strong earthquakes has mostly focused on finding the phenomena. Some attempts on getting regularity were comparatively subjective. This paper suggests that there should be indices of migration in earthquake dataset and the indexes should have statistical meaning if there is regularity in the migration of strong earthquakes. In this study, three derivative attributes of migration, i.e., migration orientation, migration distance and migration time interval, were statistically analyzed. Results in the North china region show that the migration of strong earthquakes has statistical meaning. There is a dominant migration orientation (W by S to E by N), a dominant distance (≤1.0km and on the confines of 300～700km), and a dominant time interval (≤1. and on the confines of 3～4a). The results also show that the migration will differ slightly with different {1.gnitude range or earthquake activity phase.

关键词： Migration of strong earthquakes Statistical analysis The North china region

Spatial Information Research for Temperature and Precipitation Climate Data in Hengduan Mountains

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Meteorological and environmental Research 2011年第4期2卷 26-29页

作者： ye Jiang-xia {1. of resources, Southwest Forestry university, Kunming 650224, china

[Objective] The aim was to study the spatial information of temperature and precipitation data in Hengduan mountains. [Method] Considering GIS spatial interpolation and numerical statistics theory, spatial prediction were carried out to the ten {1.ars average temperature and precipitation flux observation data in 1.9 sparse meteorological stations in Hengduan Mountains. Based on the spatial range of geographic position of Hengduan Mountains, and 1.1.000 000 scale DEM as data sources, and using trend surface simulation and residual ordinary Kriging interpolation correction method, the spatial continuous surface for annual average temperature and precipitation were studied. [Result] It was scientific and reasonable to use certain unevenly distributed sparse climate observation station value, and by dint of trend simulation and residue interpolation method to get climate consecutive spatial result. This method can not only accurate the temperature and precipitation spatial distributions to grid point, but also can reflect macro and micro geography factors and topographic influence factor of variation. Furthermore, it can be predicted error term trend surface reasonable spatial distribution. Simulation results were basically in accordance with the objective law, and can be used for the region climate data spatial informatization simulation. [Conclusion] The study provided scientific spatial basic data for the further study of ecological and vegetation in Hengduan Mountains.

关键词： Hengduan Mountains Climate {1. Spatial information Trend simulation Residue ordinary Kriging interpolation china

紫色土磷素流失的环境风险评估-土壤磷的“临界值”

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土壤通报 2011年第5期42卷 1153-1158页

作者：李学平石孝均刘萍隋涛滨州学院城市与环境系山东滨州256600 西南大学资源环境学院四川重庆400716

采用室内培养的方法,研究了3种类型的紫色土旱地和淹水土壤磷素流失的环境阈值。结果表明:无论是淹水土壤或旱地生境,3种紫色土Olsen-P与CaCl2-P之间都存在一个"临界值",酸性、中性和钙质紫色土磷素淋失临界点的Olsen-P含量分别为67.2、... 详细信息

采用室内培养的方法,研究了3种类型的紫色土旱地和淹水土壤磷素流失的环境阈值。结果表明:无论是淹水土壤或旱地生境,3种紫色土Olsen-P与CaCl2-P之间都存在一个"临界值",酸性、中性和钙质紫色土磷素淋失临界点的Olsen-P含量分别为67.2、85.8和1.3.8 mg kg-1.淹水土壤磷素环境敏感值在酸性、中性和钙质紫色土上,Olsen-P含量分别为49.2、77.9和92.1.mg kg-1.3种紫色土在淹水还原条件下土壤磷环境敏感临界值比旱地低,淹水还原条件提高了紫色土磷向水体释放的风险。淹水土壤Olsen-P含量与田表水TP、DP浓度之间存在"临界值",酸性、中性和钙质土临界值处土壤Olsen-P含量分别为(65±1.41.mg kg-1.、96.7±2.7)mg kg-1.(1.5.5±1.1.mg kg-1.土壤0.01.mol L-1.CaCl2-P与田表水TP、DP之间呈极显著的线性关系。可以利用这些指标对紫色土区域土壤磷环境风险进行评价,并确定区域磷肥的最佳管理策略。

关键词：紫色土 Olsen-P CaCl2-P 临界值

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Hazard Assessment of Urban Flood Disaster and Safety Protection Strategy for Flood Disaster Prevention and Reduction in china

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Hazard Assessment of Urban Flood Disaster and Safety Protect...

Modeling the Roles of Precipitation Increasing in Glacier Systems Responding to Climate Warming—Taking Xinjiang Glaciated Region as Example

2004安全科学与技术国际会议

作者： WANG Jingai1 2 3 WANG Jue1 2 & ye tao1 3 (1 school of Geography Beijing Normal university Beijing 100875 china) (2 Key Laboratory of Regional Geography of Beijing Normal university Beijing Normal university Beijing 100875 china) (3Key Laboratory of environmental Change and National Disaster of Ministry of Education of china Beijing Normal university Beijing 100875 china)

Based on disaster system theory and analysis of 70 cities in china whose population is over 600 thousand, a hazard assessment system has been established combining hazard-for{1.tive environments, hazar

关键词： urban flood disaster system integrated hazard index security of urban areas security protection strategy for flood prevention and reduction

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Journal of Mountain Science 2005年第4期2卷 306-312页

作者： WANG Xin XIE Zichu LIU Shiyin tao Jianjun HAN Yongshun YANG Yuelong Research Institute of Geo-spatial Information Science Hunan University of Science ＆ Technology Xiangtan 411201 Hunan China Key Laboratory of Ice Core and Cold Region＇s Environment Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China Institute of resources and Environment Hunan Normal University Changsha 410081 China Institute of Tibetan Plateau Research CAS Beijing 100029 China

The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 50 {1.ars, although there were surely some uncertainties in precipitation predictions. On the basis of the structure of glacier system and nature of equilibrium line altitude at steady state （ELAo）, a functional model of the glacier system responding to climate changes was established, and it simultaneously involved the rising of summer mean temperature and increasing of mean precipitation. The results from the functional model under the climatic scenarios with temperature increasing rates of 0.01. 0.03 and 0.05 K/{1.ar indicated that the precipitation increasing would play an evident role in glacier system responding to climate change： if temperature become 1.℃ higher, the precipitation would be increased by 1.%, which can slow down the glaciers retreating rate in the area by 4 %, accelerate runoff increasing rate by 8 % and depress the ELAo rising gradient by 24 m in northern Xinjiang glacier system where semi-continental glaciers dominate, while it has corresponding values of only 1., 5 % and 1.m respectively in southern Xinjiang glacier system, where extremely continental glaciers dominate.

关键词： Glacier system climate warming precipitation increasing role

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Absorption and Accumulation of Heavy Metals for Phyllostachys pubescens in Catchment of Southern Jiangsu Province

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Absorption and Accumulation of Heavy Metals for Phyllostachy...

柱状药包爆破过程中应力波叠加与岩体裂隙分布的方向效应研究

海峡两岸三地环境与资源学术研讨会暨第二届中国环境资源与生态保育学会会员代表大会

作者： tao Bao-xian~(1.2,3),ZHANG Jin-chi~(1.*) 1.College of Forestry {1. and Environment,Nanjing Forestry university,Nanjing 21.037,china 2.College of Chemistry,{1. & Environment,Linyi Normal university,Linyi 276005,china 3.Key Laboratory of Water,Soil Conservation and environmental Protection,Linyi 276005,china.

The studies were carried out on the absorption and accumulation of heavy metals in the hilly region of Southern Jiangsu *** results showed that:the forest soil in studied areas was not been polluted,owing to forest's function of accumulating heavy *** content of Zn was bigger man other 4 heavy metals in the organs of Phyllostachys *** total storage of heavy metals were Zn>Cu>Pb>Ni>*** the enrichment coefficient of heavy metals were *** annual uptake of Cr, Cu,Ni,Pb,Zn for Phyllostachys pubescens were 29.1.g/hm,278.31./hm,89.44g/hm,87.43g/hm, 1.4.69g/hm respectively,annual return of Cr,Cu,Ni,Pb,Zn for Phyllostachys pubescens were 5.79g/hm, 25.84g/hm,5.1.g/hm,42.06g/hm,1.2.56g/hm respectively,and the turnover period of Cr,Cu,Ni,Pb,Zn was 5、1.、1.、2、1.a for Phyllostachys *** to the results of assessment,the Phyllostachys pubescens has lower enrichment coefficient,it has better ability to absorb and accumulate heavy metals in soil,owning to the bigger biomass and productivity.

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岩石力学与工程学报 2024年第2期43卷 399-411页

作者：雷涛康普林叶海旺李宁王其洲武汉理工大学矿物资源加工与环境湖北省重点实验室湖北武汉430070 武汉理工大学资源与环境工程学院湖北武汉430070

深孔爆破中,起爆位置决定了爆轰波的传爆方向,进而影响爆炸应力场及岩体裂隙分布。基于Starfield迭加原理,推导链状球药包应力场传播与叠加规律,构建等效柱状药包理论模型,引入链状球药包载荷延时加载方法,开展柱状药包迭加应力场离散... 详细信息

深孔爆破中,起爆位置决定了爆轰波的传爆方向,进而影响爆炸应力场及岩体裂隙分布。基于Starfield迭加原理,推导链状球药包应力场传播与叠加规律,构建等效柱状药包理论模型,引入链状球药包载荷延时加载方法,开展柱状药包迭加应力场离散元数值仿真,研究各传爆方向下岩体裂隙分布规律的方向效应。结果表明:由于爆炸应力波存在相位延迟,柱状药包的应力波叠加和裂隙分布存在显著的方向效应,应力波沿传爆方向产生较强叠加,叠加应力幅值的增长速度先增大后减小,裂隙分布范围也沿传爆方向逐渐增大;对于不同的传爆方向,底部或上部单侧传爆时,裂隙总体沿传爆方向呈“漏斗状”分布,两端同时向中间传爆时,裂隙在炮孔中心附近最为发育,整体呈“纺锤状”分布,中部起向两端传爆时,裂隙在炮孔两端分布略广,整体分布较为均匀,裂隙分布情况可较好反映各传爆方向下迭加应力场的分布规律;不同传爆方向下等效柱状药包的应力波叠加效果可合理解释岩体中裂隙发育与演化过程,揭示了其方向效应机制。

关键词：爆破工程岩体爆破柱状药包传爆方向应力波叠加裂隙分布

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