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山东省东平-汶上地区铁矿矿床成因探讨 被引量:8
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作者 张国权 《山东国土资源》 2017年第6期23-29,共7页
山东省东平-汶上铁矿成矿带是鲁西重要的成矿带,区内已发现李官集、彭集等多个大中型铁矿床,探明了铁矿石资源量超过12亿t。通过收集东平-汶上地区基础地质调查、区域重磁、矿产勘查、科研成果等资料,分析了区内地层、构造、岩浆岩及区... 山东省东平-汶上铁矿成矿带是鲁西重要的成矿带,区内已发现李官集、彭集等多个大中型铁矿床,探明了铁矿石资源量超过12亿t。通过收集东平-汶上地区基础地质调查、区域重磁、矿产勘查、科研成果等资料,分析了区内地层、构造、岩浆岩及区域航磁异常特征、重力异常特征与铁矿床的对应耦合关系,提出了矿床的3个控矿因素:即控矿地层(泰山岩群雁翎关组、山草峪组,地层控矿专属性)、控矿构造(同斜复式背斜构造)、控矿岩浆岩(改造和破坏了铁矿带的完整性),通过对成矿区带样品采集测试,分别从主量元素、稀土元素、微量元素、原岩恢复、变质岩构造背景等方面进行系统分析对比,探讨了该区铁矿床为海相岛弧火山——沉积变质成因。 展开更多
关键词 铁矿 矿床成因 东平-汶上地区
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山东省东平——汶上地区铁矿床地质特征及成矿模式 被引量:5
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作者 张英梅 《山东国土资源》 2018年第4期8-13,共6页
研究区为鲁西地区重要的成矿带——东平—汶上铁矿带,该铁矿带内已探明彭集、张家毛坦、化肥厂等多个大中型铁矿床,说明该成矿带具备优越的成矿地质条件及良好的找矿潜力。通过剖析近年来区内典型矿床的最新勘查成果,从矿床控矿地层、... 研究区为鲁西地区重要的成矿带——东平—汶上铁矿带,该铁矿带内已探明彭集、张家毛坦、化肥厂等多个大中型铁矿床,说明该成矿带具备优越的成矿地质条件及良好的找矿潜力。通过剖析近年来区内典型矿床的最新勘查成果,从矿床控矿地层、成矿时代、成矿物质来源、矿化阶段、矿体特征及物探异常等8个方面进行系统分析,开展了铁矿成矿规律研究;根据东平—汶上铁矿带的成矿时代、赋矿层位、含铁建造及岩石组合,结合成矿规律的分析,初步建立了"东汶式"铁矿床成矿模式。 展开更多
关键词 铁矿 地质特征 成矿规律 成矿模式 BIF 东平-汶上地区
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豫东平原地区秋繁管理
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作者 刘诚 《中国养蜂》 2004年第5期18-18,共1页
关键词 东平地区 管理 秋季 繁殖 蜜蜂 蜂螨
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严实父子与金元之交的东平文化 被引量:3
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作者 晏选军 《殷都学刊》 2001年第4期54-58,共5页
金元之际,严实父子治理东平地区近50年,一面招致流亡文 士,复兴金源文化,一面兴学养士,为元朝培养了大批人才,也为散曲等多种文学样式的繁 荣奠定了坚实的基础。在一定程度上扫除了改朝换代之际文化恹恹不振的局面,起到了发轫 ... 金元之际,严实父子治理东平地区近50年,一面招致流亡文 士,复兴金源文化,一面兴学养士,为元朝培养了大批人才,也为散曲等多种文学样式的繁 荣奠定了坚实的基础。在一定程度上扫除了改朝换代之际文化恹恹不振的局面,起到了发轫 元朝自身文化的作用。 展开更多
关键词 严忠济 严忠范 学风 人才培养 教曲 严实 东平地区 金源文化 元朝
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豫东平原聚落景观格局变化 被引量:15
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作者 杨慧敏 娄帆 +1 位作者 李小建 白燕飞 《生态学报》 CAS CSCD 北大核心 2017年第16期5313-5323,共11页
中国的快速城镇化必然导致聚落景观格局的变化,但目前相关研究对平原地区关注相对较少。文中选取豫东平原地区的开封、商丘、周口市,运用GIS空间分析方法和ENVI遥感影像处理技术,对该地区1972、2015年市域中观尺度上的聚落规模、聚落景... 中国的快速城镇化必然导致聚落景观格局的变化,但目前相关研究对平原地区关注相对较少。文中选取豫东平原地区的开封、商丘、周口市,运用GIS空间分析方法和ENVI遥感影像处理技术,对该地区1972、2015年市域中观尺度上的聚落规模、聚落景观空间变化特征进行分析。结果显示:(1)在聚落发展过程中,1972—2015年聚落斑块数量有所减少,聚落规模逐渐扩张,市域内最大聚落斑块扩张相对更为明显;对聚落斑块扩张强度的分析发现,城市市辖区及周边乡镇聚落扩张强度相对较高。(2)地区内聚落斑块空间分布表现出聚集分布特征,但该时期聚集程度有所减弱;两个年份聚落核密度分布格局大致相似,局部地区存在多核扩散现象,市域尺度上的核密度分布存在地区差异。(3)对斑块形状指数的分析发现,研究区狭长或曲折聚落斑块在空间上分散布局,整体上区域内聚落形状趋于规则。(4)随着距河流、道路距离的增加,聚落斑块总面积和数量有所减少,且道路对聚落分布仅在一定范围内存在较大影响,距中心城市0—6km范围内聚落受中心城区发展辐射影响较大。本文的分析可为平原地区聚落景观的优化布局和聚落用地的集约化发展提供一定的参考。 展开更多
关键词 聚落斑块 景观格局 空间分布 东平地区
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豫东平原农用地流转机制研究 被引量:1
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作者 陈常优 毋晓蕾 叶枫 《中国农学通报》 CSCD 北大核心 2010年第3期332-336,共5页
目前,中国农用地资源的稀缺性与农用地资源粗放掠夺的经营方式并存,农用地流转迫切要求引入市场机制和宏观调控机制。系统阐述了农用地流转的市场机制和宏观调控机制,在对豫东平原地区农户实地调查的基础上,运用问卷调查法,分析了豫东... 目前,中国农用地资源的稀缺性与农用地资源粗放掠夺的经营方式并存,农用地流转迫切要求引入市场机制和宏观调控机制。系统阐述了农用地流转的市场机制和宏观调控机制,在对豫东平原地区农户实地调查的基础上,运用问卷调查法,分析了豫东平原地区农用地流转机制,如在市场机制中出现供求机制失效,价格机制失灵,竞争机制未能形成等情况;在宏观调控机制中出现土地制度和相关环境政策的制约。针对性地提出了完善和创新农用地流转机制的建议。 展开更多
关键词 农用地流转 机制 东平地区
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对蒙元时期东平杂剧的历史考察
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作者 林威 《山东社会科学》 2004年第6期99-101,共3页
虽然蒙元时期战乱频仍 ,元代散曲杂剧却诞生并繁荣于此时。东平地区有着相对稳定的社会环境和繁荣的文化教育事业 ,加之得天独厚的历史机遇 ,东平杂剧发展成为元代杂剧的源头之一 。
关键词 蒙元时期 东平地区 杂剧
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豫东平原地区田间持水量测定及误差分析
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作者 张媛媛 《河南水利与南水北调》 2023年第6期20-22,共3页
田间持水量是土壤墒情分析和干旱评估的重要指标。土壤相对湿度的确定,即干旱程度评估,田间持水量的测定是首要必须完成的工作,测定精度直接影响旱情评估的准确性,而田间持水量的测定方法有多种,测定结果均存在一定误差,文章采用自然降... 田间持水量是土壤墒情分析和干旱评估的重要指标。土壤相对湿度的确定,即干旱程度评估,田间持水量的测定是首要必须完成的工作,测定精度直接影响旱情评估的准确性,而田间持水量的测定方法有多种,测定结果均存在一定误差,文章采用自然降水法、实验室环刀、移动墒情仪法及电导率法测得的数据进行对比分析,进而提出合理监测方案,确保田间持水量符合当地实际,准确计算灌溉定额,更好地指导农业生产。 展开更多
关键词 东平地区 田间持水量 测定 对比分析
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豫东平原地区县域聚落变化特征的一般性及差异性分析 被引量:2
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作者 杨慧敏 李小建 《河南大学学报(自然科学版)》 CAS 2022年第3期253-265,共13页
以豫东平原21个县域单元为研究案例区,采用遥感影像数据与GIS空间分析技术对40多年间县域尺度上聚落变化特征的一般性和差异性进行研究,并对其驱动机理进行探讨.结果表明:(1)研究时段各县域内聚落均表现为总面积增加及斑块数量减少的特... 以豫东平原21个县域单元为研究案例区,采用遥感影像数据与GIS空间分析技术对40多年间县域尺度上聚落变化特征的一般性和差异性进行研究,并对其驱动机理进行探讨.结果表明:(1)研究时段各县域内聚落均表现为总面积增加及斑块数量减少的特征;县域尺度上城乡聚落规模分布的齐夫指数均偏小,但多数县域呈上升态势,表明其聚落规模结构相对均衡,较大规模聚落发育不够突出;经济发展水平较高的县域其聚落规模体系的变动更为显著.(2)1972-2015年县域聚落空间分布由集聚分布向离散分布变化;聚落空间扩张强度较大的地区主要分布在县(市)中心邻近区位,但不同县域存在着空间异质性.(3)研究区县域聚落变化受人口、经济和交通等因素驱动,且这些因素所引致的差异程度在逐渐增强.该研究结果可对乡村聚落调整和聚落体系优化发展提供重要参考. 展开更多
关键词 聚落斑块 变化特征 驱动机理 县域单元 东平地区
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Agriculture Development-induced Surface Albedo Changes and Climatic Implications Across Northeastern China 被引量:16
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作者 ZHANG Xuezhen WANG Wei-Chyung +2 位作者 FANG Xiuqi YE Yu ZHENG Jingyun 《Chinese Geographical Science》 SCIE CSCD 2012年第3期264-277,共14页
To improve the understandings on regional climatic effects of past human-induced land cover changes,the surface albedo changes caused by conversions from natural vegetation to cropland were estimated across northeaste... To improve the understandings on regional climatic effects of past human-induced land cover changes,the surface albedo changes caused by conversions from natural vegetation to cropland were estimated across northeastern China over the last 300 years,and its climatic effects were simulated by using the Weather Research and Forecasting (WRF) model.Essential natural vegetation records compiled from historical documents and regional optimal surface albedo dataset were used.The results show that the surface albedo decreased by 0.01-0.03 due to conversions from grassland to cropland in the Northeast China Plain and it increased by 0.005-0.015 due to conversions from forests to cropland in the surrounding mountains.As a consequence,in the Northeast China Plain,the surface net radiation increased by 4-8 W/m 2,2-5 W/m 2,and 1-3 W/m 2,and the climate was therefore warmed by 0.1℃-0.2℃、0.1℃-0.2℃、 0.1℃-0.3 ℃ in the spring,autumn and winter,respectively.In the surrounding mountain area,the net radiation decreased by less than 1.5 W/m 2,and the climate was therefore cooled too slight to be detected.In summer,effects of surface albedo changes on climate were closely associated with moisture dynamics,such as evapotranspiration and cloud,instead of being merely determined by surface radiation budget.The simulated summer climatic effects have large uncertainties.These findings demonstrate that surface albedo changes resulted in warming climate effects in the non-rainy seasons in Northeast China Plain through surface radiation processes while the climatic effects in summer could hardly be concluded so far. 展开更多
关键词 surface albedo land cover change climatic effects last 300 years northeastern China
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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 hydrogen and oxygen stable isotopes GROUNDWATER PRECIPITATION water cycle RECHARGE
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Warming over the North Pacific can intensify snow events in Northeast China 被引量:3
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作者 FENG Ye CHEN Huo-Po 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第2期122-128,共7页
The variation of winter snowfall intensity over Northeast China and its relationship with the autumn North Pacific SST are investigated for the period 1960–2012. An upward trend is apparent for the winter snowfall in... The variation of winter snowfall intensity over Northeast China and its relationship with the autumn North Pacific SST are investigated for the period 1960–2012. An upward trend is apparent for the winter snowfall intensity over Northeast China during the last half-century, coinciding with an increasing autumn SST over the North Pacific. Their interannual correlation coefficient reaches up to 0.58 for the past five decades, and 0.42 after their trends are removed. Further analyses indicate that the warming SST during autumn may persist into winter. Correspondingly, large parts of East Asia and the North Pacific are dominated by an anticyclonic anomaly, which can induce an anomalous southeasterly over Northeast China, weaken the northerly wind, then warm the surface, increase the water vapor content and intensify snowfall events. Thus, the autumn North Pacific SST can be considered as a key predictor for winter snowfall events over Northeast China. Results from leaveone-out cross-validation and independent validation both show a significant correlation and a small RMSE between prediction and observation. Therefore, the autumn SST over the North Pacific is suggested as a potential predictor for winter snowfall intensity in Northeast China. 展开更多
关键词 Winter snowfall intensity Northeast China North Pacific sea surface temperature Prediction
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Co-occurrence Patterns of Above-ground and Below-ground Mite Communities in Farmland of Sanjiang Plain, Northeast China 被引量:7
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作者 LIN Lin GAO Meixiang +3 位作者 LIU Dong ZHANG Xueping WU Haitao WU Donghui 《Chinese Geographical Science》 SCIE CSCD 2014年第3期339-347,共9页
One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, litt... One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The pattern of the above-ground mite commu- nity was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite com- munities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale. 展开更多
关键词 above-ground mite below-ground mite mite communities co-occurrence patterns interspecific competition species pairassociations
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Analysis of China's Haze Days in the Winter Half-Year and the Climatic Background during 1961–2012 被引量:6
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作者 SONG Lian-Chun GAO Rong +1 位作者 LI Ying WANG Guo-Fu 《Advances in Climate Change Research》 SCIE 2014年第1期1-6,共6页
The characteristics of haze days and the climatic background are analyzed by using daily observations of haze,precipitation,mean and maximum wind speed of 664 meteorological stations for the period of 1961–2012.The r... The characteristics of haze days and the climatic background are analyzed by using daily observations of haze,precipitation,mean and maximum wind speed of 664 meteorological stations for the period of 1961–2012.The results show that haze days occur significantly more often in eastern China than in western China.The annual number of haze days is 5–30 d in most parts of central-eastern China,with some areas experiencing more than 30 d,while less than 5 d are averagely occurring in western China.Haze days are mainly concentrated in the winter half-year,with most in winter,followed by autumn,spring,and then summer.Nearly 20%of annual haze days are experienced in December.The haze days in central-eastern China in the winter half-year have a significant increasing trend of 1.7 d per decade during 1961–2012.There were great increases in haze days in the 1960s,1970s and the beginning of the 21st century.There was also significant abrupt changes of haze days in the early 1970s and 2000s.From 1961 to 2012,haze days in the winter half-year increased in South China,the middle-lower reaches of the Yangtze River,and North China,but decreased in Northeast China,eastern Northwest China and eastern Southwest China.The number of persistent haze is rising.The Longer the haze,the greater the proportion to the number persistent haze.Certain climatic conditions exacerbated the occurrence of haze.The correlation coefficient between haze days and precipitation days in the winter half-year is mainly negative in central-eastern China.The precipitation days show a decreasing trend in most parts of China,with a rate of around–4.0 d per decade in central-eastern China,which reduces the sedimentation capacity of atmospheric pollutants.During the period of 1961–2012,the correlation coefficients between haze days and mean wind speed and strong wind days are mainly negative in central-eastern China,while there exists positive correlation between haze days and breeze days in the winter half-year.The mean wind speed and strong wind days are decreasing,while breeze days are increasing in most parts of China,which is benefitial to the reduction of the pollutants diffusion capacity.As a result,haze occurs more easily. 展开更多
关键词 HAZE winter half-year precipitation days wind speed
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Trophic Ecology of Sharks in the Mid-East Pacific Ocean Inferred from Stable Isotopes 被引量:6
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作者 LI Yunkai GONG Yi +2 位作者 CHEN Xinjun DAI Xiaojie ZHU Jiangfeng 《Journal of Ocean University of China》 SCIE CAS 2014年第2期278-282,共5页
As apex predators, sharks are of ecological and conservation importance in marine ecosystems. In this study, trophic positions of sharks were estimated using stable isotope ratios of carbon and nitrogen for five repre... As apex predators, sharks are of ecological and conservation importance in marine ecosystems. In this study, trophic positions of sharks were estimated using stable isotope ratios of carbon and nitrogen for five representative species caught by the Chinese longline fleet in the mid-east Pacific, i.e., the blue shark (Prionace glauca), the bigeye thresher shark (Alopias superciliosus), the silky shark (Carcharhinus falciformis), the scalloped hammerhead (Sphyrna lewini), and the oceanic whitetip shark (Car-charhinus longimanus). Of these species, oceanic whitetip shark has the lowest trophic level and mean 815N value (3.9 and 14.93%o± 0.84%o), whereas bigeye thresher shark has the highest level/values (4.5 and 17.02%o±1.21%o, respectively). The bigeye thresher shark has significantly higher 515N value than other shark species, indicating its higher trophic position. The blue shark and oceanic whitetip shark has significantly higher 813C values than bigeye thresher shark, silky shark and scalloped hammerhead, possibly due to different diets and/or living habitats. The stable isotope data and stomach content data are highly consistent, suggesting that sta-ble isotope analysis supplements traditional feeding ecology study of sharks, and thus contributes to understanding their trophic linkage. 展开更多
关键词 trophic level stable isotope analysis mid-east Pacific SHARK
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Comparison of semivariogram models for kriging monthly rainfall in eastern China 被引量:5
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作者 汤燕冰 《Journal of Zhejiang University Science》 CSCD 2002年第5期584-590,共7页
An exploratory spatial data analysis method (ESDA) was designed Apr.28,2002 for kriging monthly rainfall. Samples were monthly rainfall observed at 61 weather stations in eastern China over the period 1961-1998. Comp... An exploratory spatial data analysis method (ESDA) was designed Apr.28,2002 for kriging monthly rainfall. Samples were monthly rainfall observed at 61 weather stations in eastern China over the period 1961-1998. Comparison of five semivariogram models (Spherical, Exponential, Linear, Gaussian and Rational Quadratic) indicated that kriging fulfills the objective of finding better ways to estimate interpolation weights and can provide error information for monthly rainfall interpolation. ESDA yielded the three most common forms of experimental semivariogram for monthly rainfall in the area. All five models were appropriate for monthly rainfall interpolation but under different circumstances. Spherical, Exponential and Linear models perform as smoothing interpolator of the data, whereas Gaussian and Rational Quadratic models serve as an exact interpolator. Spherical, Exponential and Linear models tend to underestimate the values. On the contrary, Gaussian and Rational Quadratic models tend to overestimate the values. Since the suitable model for a specific month usually is not unique and each model does not show any bias toward one or more specific months, an ESDA is recommended for a better interpolation result. 展开更多
关键词 KRIGING Semivariogram model Monthly rainfall Eastern China
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Analysis of developing non-timber forest products of Sanjiang Plain, Northeast China 被引量:1
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作者 LIU Tong ZHOU Zhi-qiang 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期339-341,共3页
The Sanjiang Plain is a vast area of alluvial floodplains and low hills in northeast Heilongjiang Province. Because of the excessive land reclamation in the past, the whole forest area and the quality have decreased. ... The Sanjiang Plain is a vast area of alluvial floodplains and low hills in northeast Heilongjiang Province. Because of the excessive land reclamation in the past, the whole forest area and the quality have decreased. In the view of sustainable development, this paper analyzed the possibilities for Non-timber Forest Product in terms of developing potentialities, markets, social effects and the status of NTFPs in several counties of Sanjiang Plain. The result showed that, active development and management for NTFPs is an optimistic option to how to balance the wetlands conservation and sustainable economic development. 展开更多
关键词 Sanjiang Plain NTFP developing potentialities MARKETS social effects
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Simulating Net Carbon Budget of Forest Ecosystems and Its Response to Climate Change in Northeastern China Using Improved FORCCHN 被引量:6
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作者 ZHAO Junfang YAN Xiaodong JIA Gensuo 《Chinese Geographical Science》 SCIE CSCD 2012年第1期29-41,共13页
As dominant biomes,forests play an important and indispensable role in adjusting the global carbon balance under climate change.Therefore,there are scientific and political implications in investigating the carbon bud... As dominant biomes,forests play an important and indispensable role in adjusting the global carbon balance under climate change.Therefore,there are scientific and political implications in investigating the carbon budget of forest ecosystems and its response to climate change.Here we synthesized the most recent research progresses on the carbon cycle in terrestrial ecosystems,and applied an individual-based forest ecosystem carbon budget model for China(FORCCHN) to simulate the dynamics of the carbon fluxes of forest ecosystems in the northeastern China.The FORCCHN model was further improved and applied through adding variables and modules of precipitation(rainfall and snowfall) interception by tree crown,understory plants and litter.The results showed that the optimized FORCCHN model had a good performance in simulating the carbon budget of forest ecosystems in the northeastern China.From 1981 to 2002,the forests played a positive role in absorbing carbon dioxide.However,the capability of forest carbon sequestration had been gradually declining during the the same period.As for the average spatial distri-bution of net carbon budget,a majority of the regions were carbon sinks.Several scattered areas in the Heilongjiang Province and the Liaoning Province were identified as carbon sources.The net carbon budget was apparently more sensitive to an increase of air temperature than change of precipitation. 展开更多
关键词 net carbon budget climate change northeastern China improved FORCCHN
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Evaluation of tidal stream energy and its impacts on surrounding dynamics in the Eastern Region of Pingtan Island, China 被引量:2
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作者 武贺 王鑫 +2 位作者 王兵振 白杨 王培涛 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第6期1319-1328,共10页
Using an improved FVCOM numerical model, combined with the momentum-sinking scheme based on the structural characteristics of specific turbines, this study analyzed the temporal and spatial distributions of tidal ener... Using an improved FVCOM numerical model, combined with the momentum-sinking scheme based on the structural characteristics of specific turbines, this study analyzed the temporal and spatial distributions of tidal energy resources before and after the deployment of tidal turbines near Pingtan Island, China. Considering factors such as the distribution of tidal stream energy, bathymetry, topography, and the design parameters of the turbines, an appropriate location for a demonstration tidal turbine was selected and the corresponding energy resource was evaluated. Several sites with strong tidal streams were considered: south of the northern cape, east of the southem cape, and the southern end of Haitan Bay. The former was thought most suitable for the deployment of a tidal energy turbine, with projected power generation for approximately 470 h per month. The average power of this demonstration was about 2.4 kW, and the annual electricity output was approximately 17.47 MWh. The intervention of the turbine device had little influence on the near-field tidal stream or water level. The tidal stream was reduced slightly in the area south of the northern cape, although the effect weakened further from the turbine. Conversely, the velocity increased slightly on both sides of the demonstration site. The difference in current speed with and without the turbine was greater at slack tide than still tide. The influence of turbine operation on water level was minor. The method adopted in this study can be considered a reference for the selection of sites for the demonstration of tidal stream energy. However, the method is unable describe the dynamic characteristics of the turbulent flow surrounding the deployed turbines, which has an important role regarding the optimal designs of the turbine blade and pile foundations. Therefore, we will continue to work to improve this model in future research. 展开更多
关键词 tidal stream energy Pingtan Island numerical simulation dynamic impacts
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Risk Assessment and Zoning of Agricultural Drought Disaster in Heilongjiang Province
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作者 ZHENG Kai CHEN Hong +1 位作者 ZHANG Li-juan GAO Yu-hong 《Agricultural Science & Technology》 CAS 2011年第4期588-591,共4页
In this study,we first zoned the drought degree in the years from 1971 to 2000 in Heilongjiang Province by using precipitation anomaly equation as an indicator,and analyzed the temporal distribution characteristics an... In this study,we first zoned the drought degree in the years from 1971 to 2000 in Heilongjiang Province by using precipitation anomaly equation as an indicator,and analyzed the temporal distribution characteristics and laws of arid disaster in different periods.Using the method of human being habitat risk assessment,we further studied and zoned the drought disaster risk index(DDRI)of maize cultivated in 74 stations in Heilongjiang Province via GIS software.The results showed that(1)the occurrence frequency of moderate and heavy drought in Heilongjiang Province was 1970s>1990s>1980s,and(2)the high risk area of drought disaster for maize production mainly assembled in Qiqihar and Daqing regions in west Heilongjiang Province,where agricultural drought should be highly concerned,while low risk and slight risk areas mainly distribute in middle areas and east plain areas in Heilongjiang Province.Our study provided basis for the defense of agricultural drought disaster. 展开更多
关键词 Drought disaster Risk index ZONING Helongjiang Province
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