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运东平原区1976年以来地下水位变化特征分析 被引量:3
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作者 陈皓锐 王少丽 +2 位作者 高占义 胡亚琼 黄介生 《灌溉排水学报》 CSCD 北大核心 2010年第4期114-118,共5页
利用运东平原区东光和吴桥县1976—2008年长系列的浅层地下水位观测数据,基于多种统计方法分析了该区域地下水位近33年来的趋势性、突变点、持续性、周期性和主要的气候影响因子。结果表明,地下水位年内波动受抽水灌溉和降雨的影响而表... 利用运东平原区东光和吴桥县1976—2008年长系列的浅层地下水位观测数据,基于多种统计方法分析了该区域地下水位近33年来的趋势性、突变点、持续性、周期性和主要的气候影响因子。结果表明,地下水位年内波动受抽水灌溉和降雨的影响而表现出高度一致性;近33年来,研究区地下水位主要呈现下降趋势,而东光城区则由于浅层抽水量较少而处于上升趋势;各站地下水位赫斯特指数均大于0.5,表现了很强的持续性特征;该区域地下水位在20世纪70年代末、1989年和1996年左右出现了3个拐点;地下水位以大于33年的周期变化为主,人类活动的影响使得天然周期显著减弱。 展开更多
关键词 东平原 地下水位变化 统计分析
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东平原狭蚌虫外壳的组织学研究
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作者 任素莲 王德秀 +1 位作者 胡维兴 刘竹伞 《海洋湖沼通报》 CSCD 北大核心 1999年第2期32-36,共5页
本文对东平原狭蚌虫外壳的组织结构进行了研究。外壳由内外角质层、内外上皮层和皮下结缔组织共同组成。外角质层厚,较规则。上皮细胞有柱状细胞和具有胞突的锥形细胞两种形态。同侧及相对两侧的上皮胞突相连接,构成了许多具有血细胞... 本文对东平原狭蚌虫外壳的组织结构进行了研究。外壳由内外角质层、内外上皮层和皮下结缔组织共同组成。外角质层厚,较规则。上皮细胞有柱状细胞和具有胞突的锥形细胞两种形态。同侧及相对两侧的上皮胞突相连接,构成了许多具有血细胞的血腔隙。 展开更多
关键词 东平原 狭蚌虫 外壳 组织结构
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综合整治晋江市晋东平原城区主河道的规划探讨 被引量:2
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作者 庄志农 《水利科技》 2008年第3期39-40,共2页
该文以晋江市晋东平原主要河道的综合整治规划为例,分析了流经市区的晋东平原河道综合整治涉及到的诸多问题,认为城市河道综合整治有别于传统意义上的河道整治,需要多方位考虑以及多部门、多专业的协调配合,以充分发挥河道综合功能。
关键词 综合整治 河道 规划 东平原
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Study on specifications of farmland shelterbelt net in Northeastern Plain of China 被引量:3
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作者 赵雨森 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期289-293,337,共5页
s: The farmland shelterbelts in Northeastern Plain of China have formed relatively complete net system. The func-tions of shelterbelt net in omnibearing wind check and prevention of frostbite as well as the field of ... s: The farmland shelterbelts in Northeastern Plain of China have formed relatively complete net system. The func-tions of shelterbelt net in omnibearing wind check and prevention of frostbite as well as the field of integrated climate effect within shelterbelt net were analyzed, through located observation of meteorological factors. Within the shelterbelt net, the area with more than 10% efficiency of omnibearing wind check was determined as benefited area. The analysis of yield and quality of crops indicated that the sheltering range of shelterbelt net was 25 times tree height. The mature heights of the various varieties of poplar composed the shelterbelts were determined according to their height growth. Based on the comprehensive analysis above, the suitable size of farmland shelterbelt net in Northeastern Plain of China was decided to be 400 m×400 m. 展开更多
关键词 Farmland shelterbelt Protective benefit Shelterbelt net Specifications Wind-checking efficiency
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Soil Quality Evaluation and Technology Research on Improving Land Capability——A Case Study on Huanghuaihai Plain in Shandong Province 被引量:2
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作者 王存龙 祝德成 +4 位作者 蒋文惠 赵西强 王红晋 喻超 伊飞 《Agricultural Science & Technology》 CAS 2014年第11期1960-1966,共7页
Based on the geochemical data obtained from the national project about the prevention and control of soil contamination, this paper explored the properties of soil chemical elements in Huanghuaihai Plain, Shandong Pro... Based on the geochemical data obtained from the national project about the prevention and control of soil contamination, this paper explored the properties of soil chemical elements in Huanghuaihai Plain, Shandong Province. The results showed that among the grade-one nutritive elements in soil, organic matter, nitrogen and phosphorus were relatively deficient while potassium was rich. Meanwhile, as the grade-two nutritive elements, calcium oxide and magnesium oxide were relatively short and sulfur’s content was abundant. About the other beneficial and trace nutri-tive elements, iron oxide, manganese, molybdenum and boron were deficient, but the content of chlorine was high, hardly lack. The main barriers to improving land productivity were soil salinization and soil heavy metal contamination. The values of soil integrated fertility index that most of the soil in the study area is middle-lower fertilized. Specifical y, the low fertility area and lower fertility area are 6 1604 and 1 244 km2 respectively, occupying about 97.43% and 1.97% of the total area. The moderate fertility soil has an area of 172 km2, occupying about 0.27% of the total area. The higher fertility soil covers an area of 128 km2, while the high fertility area of only 76 km2. This article proposed scientific fertilization, elimination of soil obsta-cle, remediation of heavy-metal-contaminated soil and other effective measures to improve land productivity according to the basic investigation results, which provides a good technological support for the planning and development of good-quality and high-benefit agriculture. 展开更多
关键词 Soil fertility soil-water-plant land productivity improvement Huanghuaihai Plain in Shandong Province
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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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Vegetation Change of Ecotone in West of Northeast China Plain Using Time-series Remote Sensing Data 被引量:10
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作者 HUANG Fang WANG Ping 《Chinese Geographical Science》 SCIE CSCD 2010年第2期167-175,共9页
Multi-temporal series of satellite SPOT-VEGETATION normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) data from 1998 to 2007 were used for analyzing vegetation change of the eco... Multi-temporal series of satellite SPOT-VEGETATION normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) data from 1998 to 2007 were used for analyzing vegetation change of the ecotone in the west of the Northeast China Plain. The yearly and monthly maximal values,anomalies and change rates of NDVI and NDWI were calculated to reveal the interannual and seasonal changes in vegetation cover and vegetation water content. Linear regression method was adopted to characterize the trends in vegetation change. The yearly maximal NDVI decreased from 0.41 in 1998 to 0.37 in 2007,implying the decreasing trend of vegetation activity. There was a significant decrease of maximal NDVI in spring and summer over the study period,while an increase trend was observed in autumn. The vegetation-improved regions and vegetation-degraded regions occupied 17.03% and 20.30% of the study area,respectively. The maximal NDWI over growing season dropped by 0.027 in 1998–2007,and about 15.15% of the study area showed a decreasing trend of water content. Vegetation water stress in autumn was better than that in spring. Vegetation cover and water content variations were sensitive to annual precipitation,autumn precipitation and summer temperature. The vegetation degradation trend in this ecotone might be induced by the warm-drying climate especially continuous spring and summer drought in the recent ten years. 展开更多
关键词 vegetation change normalized difference vegetation index (NDVI) normalized difference water index (NDWI) SPOT-VEGETATION ECOTONE Northeast China Plain
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The Activity of Liaocheng-Lankao Buried Fault During the Quaternary —An Important Buried Active Fault in the Eastern China Plain 被引量:1
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作者 XiangHongfa WangXuechao 《Earthquake Research in China》 2001年第2期124-133,共10页
On the basis of locating by the geochemical prospecting, shallow seismic sounding, drilling, geological profiling, and neogeochronological dating, we first found out the dislocation amount along the Liaocheng-Lankao b... On the basis of locating by the geochemical prospecting, shallow seismic sounding, drilling, geological profiling, and neogeochronological dating, we first found out the dislocation amount along the Liaocheng-Lankao buried fault since the Quaternary and the age of its latest activity phase and determined that the upper break point by the fault dislocation reaches 20 m below the surface. The latest activity phase was in the early Holocene and the fault is a shallow-buried active fault. An average dislocation rate along the fault is 0.12 nun/a since the Quaternary. Thus, it is a buried active fault with intermediate to strong movement strength in the eastern China. 展开更多
关键词 Liaocheng-Lankao buried fault Quaternary activity Integrated investigation
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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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Land Use/Cover Changes and Environmental Consequences in Songnen Plain,Northeast China 被引量:8
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作者 LIU Dianwei WANG Zongming +7 位作者 SONG Kaishan ZHANG Bai HU Liangjun HUANG Ni ZHANG Sumei LUO Ling ZHANG Chunhua JIANG Guangjia 《Chinese Geographical Science》 SCIE CSCD 2009年第4期299-305,共7页
The Songnen Plain in Northeast China,one of the key national bases of agricultural production,went through remarkable land use/cover changes in recent years.This study aimed to explore the long-term land use/cover cha... The Songnen Plain in Northeast China,one of the key national bases of agricultural production,went through remarkable land use/cover changes in recent years.This study aimed to explore the long-term land use/cover changes and the effects of these changes on the environment.The Landsat-based analysis showed that,during 1986-2000,cropland,built-up land and barren land had increased,among which cropland had the largest increase of 9,198km2 with an increase rate of 7.5%.Woodland,grassland,water body and swampland had decreased correspondingly,among which grassland had the most dramatic decrease of 6,127km2 with a decrease rate of 25.6%.The transition matrix results revealed that grassland,woodland and swampland were the three main land use types converted to cropland.Climate warming created the potential environment for the conversion of grassland and swampland into cropland.Land resources policy made by central and provincial governments of China affected the pattern and intensity of land use.Land use/cover changes accompanied by climatic variation brought out a series of environmental consequences,such as sand desertification of land,land salinization and alkalinization,grassland degradation,and more frequent floods.Under this circumstance,optimized land use structure and restoration measures are needed. 展开更多
关键词 land use change remote sensing sustainable development Songnen Plain China
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Fuzzy Synthetic Evaluation of Wetland Soil Quality Degradation:A Case Study on the Sanjiang Plain,Northeast China 被引量:16
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作者 WANG Jian-Hua LU Xian-Guo +2 位作者 JIANG Ming LI Xiao-Yan TIAN Jing-Han 《Pedosphere》 SCIE CAS CSCD 2009年第6期756-764,共9页
Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursu... Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursuit evaluation (PPE) model based on real-coded accelerating genetic algorithm were introduced to evaluate quality variations in top layers of the main wetland soils on the Sanjiang Plain in 1999 and 2003, respectively. As soil quality degradation boundaries were vague, this study established two fuzzy synthetic evaluation (FSE) models based on the original data and criteria used in the RSQE and PPE models. The outputs of the two FSE models were obtained by choosing two fuzzy composite operators M(∧, ∨) and M(·, ⊕). Statistical analysis showed that the results of the FSE, RSQE, and PPE models were correlated. In particular, outputs of the FSE model using M(·, ⊕) were significantly correlated with those of the RSQE model with r = 0.989 at P < 0.01. Compared with RSQE and PPE models, the FSE model may be more objective in showing soil quality variations and was closer to the natural situation, showing the feasibility and applicability of the FSE model in evaluating soil quality degradation. However, the choice of composite operator was of critical importance. The study of wetland soil quality degradation on the Sanjiang Plain was of scientific and practical significance for protection and management of soils and for sustainable development of agriculture in this area in the future. 展开更多
关键词 fuzzy composite operator model soil protection and management sustainable development of agriculture
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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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Characteristics of Sand Dune Pattern and Fluvial-aeolian Interaction in Horqin Sandy Land, Northeast Plain of China
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作者 DU Huishi WANG Zongming MAO Dehua 《Chinese Geographical Science》 SCIE CSCD 2018年第4期624-635,共12页
The interaction between fluvial and aeolian processes can significantly change surface morphology of the Earth. Taking the Horqin Sandy Land as the research area and using Landsat series satellite remote sensing image... The interaction between fluvial and aeolian processes can significantly change surface morphology of the Earth. Taking the Horqin Sandy Land as the research area and using Landsat series satellite remote sensing images, this study utilizes geomorphology and landscape ecology to monitor and analyze the aeolian geomorphology characteristics of the Horqin Sandy Land. Results show that the sand dunes of the Horqin Sandy Land are mainly distributed on alluvial plains along the banks of the mainstream and tributaries of the Western Liao River, and the sand dune types tend to simplify from west to east and from south to north. The aeolian geomorphology coverage tend to be decreasing in the past 40 years, with an average annual change rate of 0.31%. While the area of traveling dunes decreased, the area of fixed and semi-fixed dunes increased. The fractal dimensions of various types of sand dune have all remained relatively constant between 1.07 and 1.10, suggesting that they are experiencing a relatively stable evolutionary process. There is a complex interaction between fluvial and aeolian processes of the Horqin Sandy Land, which plays a central role in surface landscape molding. Sand dunes on both sides of different rivers on the Horqin Sandy Land present certain regularity and different characteristics in terms of morphology, developmental scale, and spatial pattern. There are six fluvial-aeolian interaction modes in this area: supply of sand sources by rivers for sand dune development, complete obstruction of dune migration by rivers, partial obstruction of dune migration by rivers, influence of river valleys on dune developmental types on both sides, influence of river valleys on dune developmental scale on both sides, and river diversion due to obstruction and forcing by sand dunes. This study deepens our understanding of the surface process mechanism of the interaction between fluvial and aeolian processes in semi-arid regions, and provides a basis for researches on regional landscape responses in the context of global environmental change. 展开更多
关键词 fluvial-aeolian interaction riverine dune landscape evolution sand dune pattern Horqin Sandy Land
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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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Mercury Distribution and Accumulation in Typical Wetland Ecosystems of Sanjiang Plain,Northeast China 被引量:2
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作者 WANG Qiang ZHANG Zhongsheng +1 位作者 ZHOU Xuehong LU Xianguo 《Chinese Geographical Science》 SCIE CSCD 2013年第1期49-58,共10页
Total mercury in soil,water,plant,insects,fishes and bird feathers were determined to study mercury distribution and accumulation in typical wetland ecosystems in the Sanjiang Plain,Northeast China.Results show that t... Total mercury in soil,water,plant,insects,fishes and bird feathers were determined to study mercury distribution and accumulation in typical wetland ecosystems in the Sanjiang Plain,Northeast China.Results show that total mercury concentrations in soils of Deyeuxia angustifolia wetland and Carex lascarpa wetland are 0.046 mg/kg and 0.063 mg/kg,respectively.Total mercury concentration in water bodies is 0.053 μg/L on average.Of four plants studied,total mercury in moss is the highest with the mean of 0.132 mg/kg.Of 10 terrestrial insect species studied,total mercury in centipede(Scolopendra spp.) is the highest with the mean of 0.515 mg/kg while total mercury in grasshopper(Oxya spp.) bodies is the lowest.Total mercury concentrations in the herbivorous,omnivorous and predatory insects are 10.18 ng/g,16.47 ng/g and 213.35 ng/g on average,respectively.Total mercury concentrations of the adult feather(549.88 ± 63.04 ng/g),nestling feather(55.15 ± 23.53 ng/g),and eggshell(22.05 ± 5.96 ng/g) of the Grey heron(Ardea cinerea) are higher than those of the Great egret(Egretta alba)(adult feather:446.57 ± 90.89 ng/g;nestling feather:32.99 ± 17.15 ng/g;eggshell:21.02 ± 3.17 ng/g) in the wetlands of the Sanjiang Plain.The bioconcentration factors decrease in the order of piscivorous fish muscle > omnivorous fish muscle > herbivorous fish > insect. 展开更多
关键词 MERCURY soil plant INSECT fish WATERBIRD BIOCONCENTRATION Sanjiang Plain Northeast China
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Change of ancient hydrology net in Northeast China Plain
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作者 Hui QU Yu CHU +2 位作者 Fenglong ZHANG Full QI Xiangkui YANG 《Global Geology》 2006年第2期253-257,共5页
Comparing with lithofacies palaeogeography of several great plains,the authors analyzed four great plains in Quaternary diastrophism,the sedimentary facies,sedimentary environment and their evolution from the independ... Comparing with lithofacies palaeogeography of several great plains,the authors analyzed four great plains in Quaternary diastrophism,the sedimentary facies,sedimentary environment and their evolution from the independent embryonic and river system of ancient Heilongjiang finally to the Halar highland,Songnen Plain,Sanjiang Plain,the Xingkai Lake Plain and various river systems,collected the unification outside the system of Heilongjiang River to release into the sea,south ancient Xialiao River finally piracy Dongliao River,Xialiao River had released into the sea the ancient water law vicissitude and the evolved rule. 展开更多
关键词 Northeast Plain ancient hydrology net CHANGE
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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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Vegetation Development and Water Level Changes in Shenjiadian Peatland in Sanjiang Plain,Northeast China 被引量:9
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作者 WANG Chunling ZHAO Hongyan WANG Guoping 《Chinese Geographical Science》 SCIE CSCD 2015年第4期451-461,共11页
This paper documents a 7800-year proxy record from the Shenjiadian peatland on the Sanjiang Plain in Northeast China.High-resolution plant macrofossil and colorimetric humification methods were used to reconstruct the... This paper documents a 7800-year proxy record from the Shenjiadian peatland on the Sanjiang Plain in Northeast China.High-resolution plant macrofossil and colorimetric humification methods were used to reconstruct the vegetation and hydrologic history from a 193 cm-long sedimentary profile.Detrended correspondence analysis(DCA) was applied to transform the raw plant macrofossil data into latent indices of peatland water level.The vegetation community transited from an Equisetum fluviatile community to a Carex lasiocarpa community at approximately 3800 cal yr BP and was followed by a Carex-shrub community at approximately 480 cal yr BP.Based on the plant macrofossil DCA axis 1 scores and humification values,we distinguished four hydrologic periods:a wet period from 7800 cal yr BP to 4500 cal yr BP,dry periods up to 1600 cal yr BP,drier periods until 300 cal yr BP,and the driest period from 300 cal yr BP until the present.Through a comparison with other climate records,we suggest that the East Asian summer monsoon(EAM) was the main driving force for vegetation and water level changes to the Shenjiadian peatland through its impacts on precipitation. 展开更多
关键词 plant macrofossils humification Holocene peatland Northeast China
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Transfer and Transformation of Soil Iron and Implications for Hydrogeomorpholocial Changes in Naoli River Catchment, Sanjiang Plain, Northeast China 被引量:8
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作者 JIANG Ming LU Xianguo +2 位作者 WANG Hongqing ZOU Yuanchun WU Haitao 《Chinese Geographical Science》 SCIE CSCD 2011年第2期149-158,共10页
Wetland soils are characterized by alternating redox process due to the fluctuation of waterlogged conditions. Iron is an important redox substance, and its transfer and transformation in the wetland ecosystem could b... Wetland soils are characterized by alternating redox process due to the fluctuation of waterlogged conditions. Iron is an important redox substance, and its transfer and transformation in the wetland ecosystem could be an effective indicator for the environment changes. In this paper, we selected the Naoli River catchment in the Sanjiang Plain, Northeast China as the study area to analyze the dynamics of transfer and transformation of soil iron, and the relationship between iron content change and environmental factors. The results show that the total and crystalline iron contents reach the peak in the depth of 60 cm in soil profile, while the amorphous iron content is higher in the topsoil. In the upper reaches, from the low to high landscape positions, the total and crystalline iron contents decrease from 62.98 g/kg to 41.61 g/kg, 22.82 g/kg to 10.53 g/kg respectively, while the amorphous iron content increases from 2.42 g/kg to 8.88 g/kg. Amorphous iron content has positive correlation with organic matter and soil water contents, while negative correlation with pH. Moreover, both the crystalline and amorphous iron contents present no correlation with total iron content, indicating that environmental factors play a more important role in the transfer and transformation of iron other than the content of the total iron. Different redoximorphic features were found along the soil profile due to the transfer and transformation of iron. E and B horizons of wetland soil in the study area have a matrix Chroma 2 or less, and all the soil types can meet the criteria of American hydric soil indicators except albic soil. 展开更多
关键词 wetland soil landscape position hydrogeomorpholocial condition redoximorphic feature IRON
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Scale Issues of Wetland Classification and Mapping Using Remote Sensing Images: A Case of Honghe National Nature Reserve in Sanjiang Plain, Northeast China 被引量:5
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作者 GONG Huili JIAO Cuicui +1 位作者 ZHOU Demin LI Na 《Chinese Geographical Science》 SCIE CSCD 2011年第2期230-240,共11页
Wetland research has become a hot spot linking multiple disciplines presently. Wetland classification and mapping is the basis for wetland research. It is difficult to generate wetland data sets using traditional meth... Wetland research has become a hot spot linking multiple disciplines presently. Wetland classification and mapping is the basis for wetland research. It is difficult to generate wetland data sets using traditional methods because of the low accessibility of wetlands, hence remote sensing data have become one of the primary data sources in wetland research. This paper presents a case study conducted at the core area of Honghe National Nature Reserve in the Sanjiang Plain, Northeast China. In this study, three images generated by airship, from Thematic Mapper and from SPOT 5 were selected to produce wetland maps at three different wetland landscape levels. After assessing classification accuracies of the three maps, we compared the different wetland mapping results of 11 plant communities to the airship image, 6 plant ecotypes to the TM image and 9 landscape classifications to the SPOT 5 image. We discussed the different characteristics of the hierarchical ecosystem classifications based on the spatial scales of the different images. The results indicate that spatial scales of remote sensing data have an important link to the hierarchies of wetland plant ecosystems displayed on the wetland landscape maps. The richness of wetland landscape information derived from an image closely relates to its spatial resolution. This study can enrich the ecological classification methods and mapping techniques dealing with the spatial scales of different remote sensing images. With a better understanding of classification accuracies in mapping wetlands by using different scales of remote sensing data, we can make an appropriate approach for dealing with the scale issue of remote sensing images. 展开更多
关键词 wetland classification remote sensing image spatial resolution SCALE mapping wetland
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