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A Cladistic Analysis on the Genera of Tinginae (Hemiptera:Heteroptera:Tingidae) from Northern China 被引量:1
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作者 齐宝瑛 张志军 《Zoological Research》 CAS CSCD 北大核心 2001年第1期1-8,共8页
In the present paper,the cladistics method is used to analyze the phylogenetic relationship of 16 genera of Tinginae (Hemiptera:Heteroptera:Tingidae) from northern China. 33 characters with 88 states were chosen based... In the present paper,the cladistics method is used to analyze the phylogenetic relationship of 16 genera of Tinginae (Hemiptera:Heteroptera:Tingidae) from northern China. 33 characters with 88 states were chosen based on the morphological comparison. The character matrix was formed through ingroup and outgroup analysis and computed using the computer programs MacClad (version 3 0 1), AutoDecay (version 3 0), PAUP (version 3 1 1) and Hennig 86 (version 1 5),and the same most parsimonious tree and Nelson consensus cladogram were obtained from both computation to explain the phylogenetic relationship among the genera (L=118,CI=0 454,RI=0 529). We categorized these genera involved in the analysis phylogenetically into 6 groups according to the results. They are Agramma group,Leptoypha group,Dictyla group,Catoplatus group,Physatocheila group and Derephysia group. The phylogenetic relationship among the involved genera is presented as (((((Derephysia group=( Lasiacantha ,( Acalypta ,( Galeatus ,( Dictyonota ,( Derephysia,Sphaerista ))))),Physatocheila group =(( Elasmotropis,Tingis ),(( Oncochila,Cochlochila ), Physatocheila ))),Catoplatus group= Catoplatus ),Dictyla group=( Monosteira,Dictyla )),Leptoypha group= Leptoypha ),Agramma group= Agramma ). These groups will not be regarded as higher classific taxa until more genera and data are available and further analysis are carried out. 展开更多
关键词 Tinginae Cladistic analysis Phylogenetic relationship Northern China
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南北一体:古代北方民族的中国认同与统一意识
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作者 邵磊 孙美子 《中央社会主义学院学报》 2022年第5期62-74,共13页
一部中国史,就是一部各民族交融汇聚成多元一体中华民族的历史,就是各民族共同缔造、发展、巩固统一的伟大祖国的历史。古代北方少数民族的中国认同及其对统一的执着,不仅奠定了中国历史上的版图扩大与国家统一,更促进了中华民族多元一... 一部中国史,就是一部各民族交融汇聚成多元一体中华民族的历史,就是各民族共同缔造、发展、巩固统一的伟大祖国的历史。古代北方少数民族的中国认同及其对统一的执着,不仅奠定了中国历史上的版图扩大与国家统一,更促进了中华民族多元一体格局与中华民族共同体意识的形成。在古代北方少数民族政权中华化的过程中不仅名义上成为中国,更在文化、制度等方面逐步吸收汉文明,进而丰富中华文明,为各民族共有精神家园的构筑奠定基础。 展开更多
关键词 民族 北系中国 国家认同 统一意识
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Long-Term Effect of No-Tillage on Soil Organic Carbon Fractions in a Continuous Maize Cropping System of Northeast China 被引量:26
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作者 HUANG Shan SUN Yan-Ni +2 位作者 RUI Wen-Yi LIU Wu-Ren ZHANG Wei-Jian 《Pedosphere》 SCIE CAS CSCD 2010年第3期285-292,共8页
Increasing evidence has shown that conservation tillage is an effective agricultural practice to increase carbon (C) sequestration in soils. In order to understand the mechanisms underlying the responses of soil org... Increasing evidence has shown that conservation tillage is an effective agricultural practice to increase carbon (C) sequestration in soils. In order to understand the mechanisms underlying the responses of soil organic carbon (SOC) to tillage regimes, physical fractionation techniques were employed to evaluate the effect of long-term no-tillage (NT) on soil aggregation and SOC fractions. Results showed that NT increased the concentration of total SOC by 18.1% compared with conventional tillage (CT) under a long-term maize (Zea mays L.) cropping system in Northeast China. The proportion of soil large macroaggregates (〉 2 000 μm) was higher in NT than that in CT, while small macroaggregates (250-2 000μm) showed an opposite trend. Therefore, the total proportion of macroaggregates (〉 2 000 and 250-2 000μm) was not affected by tillage management. However, C concentrations of macroaggregates on a whole soil basis were higher under NT relative to CT, indicating that both the amount of aggregation and aggregate turnover affected C stabilization. Carbon concentrations of intra-aggregate particulate organic matter associated with microaggregates (iPOM-m) and microaggregates occluded within macroaggregates (iPOM-mM) in NT were 1.6 and 1.8 times greater than those in CT, respectively. Carbon proportions of iPOM-n and iPOM-mM in the total SOC increased from 5.4% and 6.3% in CT to 7.2% and 9.7% in NT, respectively. Furthermore, the difference in the microaggregate protected C (i. e., iPOM-m and iPOM-mM) between NT and CT could explain 45.4% of the difference in the whole SOC. The above results indicate that NT stimulates C accumulation within microaggregates which then are further acted upon in the soil to form macroaggregates. The shift of SOC within microaggregates is beneficial for long-term C sequestration in soil. We also corroborate that the microaggregate protected C is useful as a pool for assessing the impact of tillage management on SOC storage. 展开更多
关键词 carbon sequestration conservation tillage particulate organic matter physical fractionation soil aggregates
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Distribution of Helicobacter pylori in north China 被引量:4
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作者 Yue-HuaGong YingWang YuanYuan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第23期3523-3527,共5页
AIM: To compare the distribution of virulence-associatedgenotypes of Helicobacter pylori(H pylori) in two areas of north China with different gastric cancer risk and furthermore probe into the pathogenicity of the bac... AIM: To compare the distribution of virulence-associatedgenotypes of Helicobacter pylori(H pylori) in two areas of north China with different gastric cancer risk and furthermore probe into the pathogenicity of the bacterium. METHODS: Gastric biopsies were taken from 355 subjects from Zhuanghe, a high risk area of gastric cancer, and 136 subjects from Shenyang, a low risk area of gastric cancer. A total of 149 H pylori strains isolated from these patients were studied by PCR for differences in the genotypes of cagA, vac A, and iceA.RESULTS: In patients with high risk for gastric cancer, higher frequencies of vacA s1 or s1m1b genotypes were found as compared to those from the low risk area. CONCLUSION: There is significantly different distribution of H pylori genotypes between Zhuanghe and Shenyang areas in north China. 展开更多
关键词 Helicobacter pylori Gastric disease CAGA VACA ICEA Virulence genotype High-risk area
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Seasonal Dynamics of Nitrogen and Phosphorus in Water and Sediment of A Multi-level Ditch System in Sanjiang Plain,Northeast China 被引量:6
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作者 GUO Le MA Keming 《Chinese Geographical Science》 SCIE CSCD 2011年第4期437-445,共9页
The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasona... The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasonal dynamics of nitrogen (N) and phosphorus (P) transportation in the ditch system and the role of different ditch size is thus crucial for water pollution control of the rivers in the Sanjiang Plain.In this study,an investigation was conducted in the Nongjiang watershed of the Sanjiang Plain to study the nutrient variation and the correlation between water and sediments in the ditch system in terms of ditch level.Water and sediments samples were collected in each ditch level in growing season at regular intervals (once per month),and TN,NO 3--N,NH 4+-N,TP,and PO 4 3--P were analyzed.The results show that nutrient contents in water were higher in June and July,especially in July,the contents of TN and TP were 3.21mg/L and 0.84mg/L in field ditch,4.04mg/L and 1.06mg/L in lateral ditch,2.46mg/L and 0.70mg/L in branch ditch,1.92mg/L and 0.63mg/L in main ditch,respectively.In August and September,the nutrient contents in the water were relatively lower.The peak value of nutrient in ditch water had been moving from the field ditch to the main ditch over time,showing a remarkable impact of ditch system on river water environment.The nutrient transfer in ditch sediments could only be found in rainfall season.Nutrient contents in ditch sediment had effect on that in ditch water,but nutrients in ditch water and sediments had different origination.Ditch management in terms of the key fac-tors is hence very important for protecting river water environment. 展开更多
关键词 multi-level ditch system nitrogen PHOSPHORUS spatio-temporal variation drainage water sediment
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Simulating Hydrologic Changes with Climate Change Scenarios in the Haihe River Basin 被引量:8
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作者 YUAN Fei XIE Zheng-Hui +1 位作者 LIU Qian XIA Jun 《Pedosphere》 SCIE CAS CSCD 2005年第5期595-600,共6页
Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3L) land... Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3L) land surface model forthe simulation of hydrologic processes at a spatial resolution of 0.25° × 0.25° in the Haihe River Basin. Three climatescenarios were considered in this study: recent climate (1961-1990), future climate A2 (1991-2100) and future climateB2 (1991-2100) with A2 and B2 being two storylines of future emissions developed with the Intergovernmental Panel onClimate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2 and B2, theHaihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production ascompared with recent climate, but would be still likely prone to water shortages in the period of 2031-2070. In addition,under future climate A2 and B2, an increase in runoff during the wet season was noticed, indicating a future rise in theflood occurrence possibility in the Haihe River Basin. 展开更多
关键词 climate change regional climate modeling system RUNOFF VIC-3L model
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Red Ratings for Loess-Paleosol Sequences on China’s Loess Plateau and Their Paleo-Climatic Implications 被引量:5
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作者 HUXue-Feng LUHua-Yu +2 位作者 XUQi DONGLi-Jing HUXing 《Pedosphere》 SCIE CAS CSCD 2004年第4期433-440,共8页
Comparisons of red ratings (RR) with Fe_d, Fe_d/Fet, clay content, andmagnetic susceptibility (x) of two loess-paleosol sequences at Luochuan and Lingtai on China's LoessPlateau were conducted to study the possibl... Comparisons of red ratings (RR) with Fe_d, Fe_d/Fet, clay content, andmagnetic susceptibility (x) of two loess-paleosol sequences at Luochuan and Lingtai on China's LoessPlateau were conducted to study the possible relationship between RR and pedogenic degrees of thetwo loess-paleosol sequences, and to discuss whether the RR could become new paleo-climaticindicators. Results showed that the RR of the two loess-paleosol sequences had positive, highlysignificant (P < 0.01) correlations with: 1) citrate-bicarbonate-dithionite (CBD) extracted iron(Fe_d), 2) ratios of CBD extracted iron to total iron (Fe_d/Fet), 3) clay (< 2 mum), and 4) magneticsusceptibility (x). This suggested that the RR of these loess-paleosol sequences could indicatedegreesof loess weathering and pedogenesis and were potential paleo-climatic proxies. The strongcorrelations of RR to Fe_d and x also implied that during pedogenic processes, pedogenic hematite inloess and paleosols were closely related to the amount of total secondary iron oxides and pedogenicferrimagnetic minerals (predominantly maghemite). 展开更多
关键词 HEMATITE loess-paleosol sequences Loess Plateau magnetic susceptibility red ratings
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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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Spatial Variability of Soil Organic Carbon Under Maize Monoculture in the Song-Nen Plain, Northeast China 被引量:19
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作者 WANG Zong-Ming , ZHANG Bai, SONG Kai-Shan, LIU Dian-Wei and REN Chun-Ying Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012 (China) 《Pedosphere》 SCIE CAS CSCD 2010年第1期80-89,共10页
Soil organic carbon (SOC) and its relationship with landscape attributes are important for evaluating current regional, continental, and global carbon stores. Data of SOC in surface soils (0–20 cm) of four main soils... Soil organic carbon (SOC) and its relationship with landscape attributes are important for evaluating current regional, continental, and global carbon stores. Data of SOC in surface soils (0–20 cm) of four main soils, Cambisol, Arenosol, Phaeozem, and Chernozem, were collected at 451 locations in Nongan County under maize monoculture in the Song-Nen Plain, Northeast China. The spatial characteristics of soil organic carbon were studied, using geographic information systems (GIS) and geostatistics. Effects of other soil physical and chemical properties, elevation, slope, and soil type on SOC were explored. SOC concentrations followed a normal distribution, with an arithmetic mean of 14.91 g kg-1 . The experimental variogram of SOC was fitted with a spherical model. There were significant correlations between soil organic carbon and bulk density (r =-0.374**), pH (r = 0.549**), total nitrogen (r = 0.781**), extractable phosphorus (r =-0.109*), exchangeable potassium (r = 0.565**), and cation exchange capacity (r = 0.313**). Generally, lower SOC concentrations were significantly associated with high elevation (r =-0.429**). Soil organic carbon was significantly negatively correlated with slope gradient (r =-0.195**). Samples of the Cambisol statistically had the highest SOC concentrations, and samples of the Arenosol had the lowest SOC value. 展开更多
关键词 GEOSTATISTICS slope soil bulk density spatial distribution
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Feeding ecology of hairtail Trichiurus margarites and largehead hairtail Trichiurus lepturus in the Beibu Gulf, the South China Sea 被引量:2
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作者 颜云榕 侯刚 +2 位作者 陈骏岚 卢伙胜 金显仕 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第1期174-183,共10页
We evaluated the feeding ecology of largehead hairtail (Trichiurus lepturus) and hairtail (T. margarites). We collected specimens from fishing ports in the Beibu Gulf (Gulf of Tonkin) from October 2008 to September 20... We evaluated the feeding ecology of largehead hairtail (Trichiurus lepturus) and hairtail (T. margarites). We collected specimens from fishing ports in the Beibu Gulf (Gulf of Tonkin) from October 2008 to September 2009 and analyzed their gut contents. We collected 857 T. lepturus and 666 T. margarites samples. The number of stomachs examined in this study was sufficient to describe the monthly and ontogenetic diet shifts for the two species, as indicated by the trophic diversity curves. T. lepturus was a general omnivore, feeding primarily on Bregmaceros rarisquamosu, Decapterus maruadsi, and Acetes chinensis. Conversely, T. margarites preyed primarily on D. maruadsi, B. rarisquamosus, B. nectabanus, and A. chinensis. Both species exhibited distinct ontogenetic diet shifts. Although the two hairtail specie fed on similar sources in the same habitat, the diet overlap was relatively low. Our results suggest that hairtail play an important role in controlling small pelagic and benthic fish populations in the gulf. This trophic correlation shall be used for developing a marine ecosystem model for the Beibu Gulf. 展开更多
关键词 feeding ecology Trichiurus margarites Trichiurus lepturus ontogenetic diet shift the Beibu Gulf South China Sea
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Spatio-temporal Characteristics of Disturbance of Land Use Change on Major Ecosystem Function Zones in China 被引量:8
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作者 NING Jia LIU Jiyuan ZHAO Guosong 《Chinese Geographical Science》 SCIE CSCD 2015年第5期523-536,共14页
In recent years, because of increasing human activities, ecosystems have been substantially disturbed and their service functions have been greatly compromised. Based on the effect of land use changes on the major eco... In recent years, because of increasing human activities, ecosystems have been substantially disturbed and their service functions have been greatly compromised. Based on the effect of land use changes on the major ecosystem services, we estimated the ecosystem comprehensive anthropogenic disturbance index(ECADI) and analyzed the spatio-temporal characteristics of changes in the ECADI in China from 1990 to 2010. The average ECADI of the major ecosystem function zones in China in 2010 is approximately 0.382. The ECADI of Northeast China and North China is slightly higher than that of Northwest China and Southwest China. Most zones have slight changes in the ECADI. The average increases of ECADI in the major ecosystem function zones in China from 1990 to 2000 and from 2000 to 2010 are 0.0024 and 0.0002, respectively. The increase is mainly due to reclamation and urbanization, whereas the decrease is due to the implementation of ecosystem protection policies. During the last 20 years, the ECADI of water resources conservation zones increased first, and then stopped. The ECADI of soil conservation zones increased first, and then declined. The ECADI of sandstorm prevention zones, biodiversity conservation zones and flooding mitigation zones increased continuously. Our results may provide proposals to the government regarding land use planning and ecosystem protection plans in the major ecosystem zones. The major ecosystem function zones in the western part of China have been protected effectively. However, the major ecosystem function zones in the eastern part of China require more protection in the future. 展开更多
关键词 land use change major ecosystems services DISTURBANCE spatiotemporal patterns China
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Baseflow Characteristics in Alpine Rivers-a Multicatchment Analysis in Northwest China 被引量:3
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作者 GAN Rong SUN Lin LUO Yi 《Journal of Mountain Science》 SCIE CSCD 2015年第3期614-625,共12页
As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchm... As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchments in the alpine that could be influenced by varieties of climatic, land cover, soil and geological factors. While numerous studies have been done on streamflow, systematic analysis of baseflow in the alpine river systems is scare. Based on historical daily streamflow data and the automated digital filter method of baseflow separation, this study investigated characteristics of hydrographs of overland flow, streamflow and baseflowof river systems fed by rainfall, snowmelt, glacier melt or mixtures of these. This study also calculated the recession constants and baseflow indices of 65 river systems. While the recession constant was o.oo34- o.o728 with a mean of o.o18, the baseflow index was 0.27-0.79 with a mean of 0.57. Further, Spearman's correlation analysis showed that the baseflow index was significantly correlated with catchment climatic factors (e.g., precipitation and temperature), topographic factors (e.g., elevation and slope) and aquifer properties represented by the recession constant. Multiple regression analysis indicated that the factors explained 65% of the variability of baseflow index in the studv area. 展开更多
关键词 Baseflow index Recession constant SNOWMELT Glacier melt Streamflow
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Suitability Evaluation of Rural Settlements Based on Accessibility of Production and Living: A Case Study of Tingzu Town in Hubei Prov- ince of China 被引量:8
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作者 LIU Yaolin YE Qingqing +2 位作者 LI Jiwei KONG Xuesong JIAO Limin 《Chinese Geographical Science》 SCIE CSCD 2016年第4期550-565,共16页
Rural settlements are the main carriers of agriculture, rural areas and farmers; thus, optimizing the production and living space of rural settlements is highly significant to rural development. Taking the effective a... Rural settlements are the main carriers of agriculture, rural areas and farmers; thus, optimizing the production and living space of rural settlements is highly significant to rural development. Taking the effective allocation of resources as the starting point, a suitability evaluation system of rural settlements, based on accessibility of production and living, was proposed in this study to provide scientific basis for the optimization of production and living space. The accessibility of production and living was measured by an im- proved two-step floating catchment area method, which considered proximity and availability based on the inclination of rural residents. The suitability evaluation system consisted of traditional suitability evaluation and newly proposed limiting factor identification based on the loss score proportion of suitability. Tingzu Town of Hubei Province, China, was chosen as the case study area. Based on the re- suits of the suitability evaluation system, corresponding suggestions on rural land consolidation, industry division, as well as the layout of health care and education facilities were proposed to optimize the production and living space of rural settlements in Tingzu Town. It is found that the suitability evaluation based on accessibility of production and living is more scientific and accurate than the traditional ones which significantly overestimate production and living convenience. Moreover, the limiting factor identification can help us put forward suggestions according to local conditions and bring about the highly targeted optimization of production and living space of rural settlements. 展开更多
关键词 rural settlements suitability evaluation accessibility of production and living two-step floating catchment area (2SFCA)method limiting factor identification Tingzu Town
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Ecological and Economic System Health Assessment Based on Fuzzy Set Pair Analysis:A Case Study of Northwest Region,China 被引量:1
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作者 Chen Junfei Zhou Xiaolan Wang Huimin 《Chinese Journal of Population,Resources and Environment》 2012年第3期107-115,共9页
Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more an... Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system. 展开更多
关键词 ecological and economic system (EES) health assess-ment fuzzy analytic hierarchy process (FAHP) set pair analysis(SPA) Pressure-State-Response (PSR)
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Index System and Influence of Drought in Northwest China
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作者 Liu Yinge Wen Yanjun 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第3期56-62,共7页
In this paper, the index systems of the agricultural drought and decrease percentage of grain crop are established. The trend and influence of drought in the region is analyzed based on the 50 years (1951-2000) stat... In this paper, the index systems of the agricultural drought and decrease percentage of grain crop are established. The trend and influence of drought in the region is analyzed based on the 50 years (1951-2000) statistical data of precipitation and 52 years (1951 2002) agricultural drought of the region, including tire provinces: Shaanxi, Gansu, Ningxia, Qinghai and Xinjiang. The result shows that the drought disaster is increasing and the most serious were in the 1970s and 1990s, and main agricultural drought is a great disaster incident. The regression prediction equation of drought and flood grades and agricultural drought areas grades are set up by the harmonic wave method, and forecasting the drought will lighten during the first ten years of the 21st century. 展开更多
关键词 DROUGHT index system influence analysis trend prediction
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Quantitative Analysis of Moisture Effect on Black Soil Reflectance 被引量:8
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作者 LIU Huan-Jun ZHANG Yuan-Zhi +4 位作者 ZHANG Xin-Le ZHANG Bai SONG Kai-Shan WANG Zong-Ming TANG Na 《Pedosphere》 SCIE CAS CSCD 2009年第4期532-540,共9页
Several studies have demonstrated that soil reflectance decreases with increasing soil moisture content, or increases when the soil moisture reaches a certain content; however, there are few analyses on the quantitati... Several studies have demonstrated that soil reflectance decreases with increasing soil moisture content, or increases when the soil moisture reaches a certain content; however, there are few analyses on the quantitative relationship between soil reflectance and its moisture, especially in the case of black soils in northeast China. A new moisture adjusting method was developed to obtain soil reflectance with a smaller moisture interval to describe the quantitative relationship between soil reflectance and moisture. For the soil samples with moisture contents ranging from air-dry to saturated, the changes in soil reflectance with soil moisture can be depicted using a cubic equation. Both moisture threshold (MT) and moisture inflexion (MI) of soil reflectance can also be determined by the equation. When the moisture range was smaller than MT, soil reflectance can be simulated with a linear model. However, for samples with different soil organic matter (OM), the parameters of the linear model varied regularly with the OM content. Based on their relationship, the soil moisture can be estimated from soil reflectance in the black soil region. 展开更多
关键词 black soil quantitative analysis remote sensing soil moisture spectral reflectance
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Pathotype Structure of Magnaporthe grisea in the Fields of Chongyang and Yuan'an in Hubei Province,China 被引量:1
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作者 YANG Xiao-lin ZHANG Shu +3 位作者 LU Liang CHANG Xiang-qian YUAN Bing YU Da-zhao 《Agricultural Science & Technology》 CAS 2011年第12期1889-1892,共4页
[Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Pr... [Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Province where rice blast occurs frequently,60 isolates which were pathotyped against two sets of host differentials:Chinese host differentials and CO39 NILs,were obtained.Then,20 pathotypes with the six indica host differentials(CO39 NILs) were observed,while 13 pathotypes in four race groups were observed out of the same single spore isolates with Chinese host differentials which consists of three indica cultivars and four japonica cultivars.The diversity of the pathotypes of M.grisea populations tested by CO39 NILs was 2.54 and the pathotype 137.1 occurred at predominantly high frequency(21.67%).The diversity of physiological races of M.grisea populations tested by Chinese host differentials was 1.22 and the race group ZA occurred at predominantly high frequency(73.33%).The diversity of physiological races of M.grisea in Chongyang and Yuan'an were also calculated.Overall,the diversity of pathotypes of M.grisea in Yuan'an was higher than that in Chongyang with the two sets of the host differentials.[Conclusion] This study provided current information on the pathotype spectrum of M.grisea populations in the rice fields of Hubei Province to allow the formulation of viable strategies for blast resistance breeding programs in Hubei Province. 展开更多
关键词 Host differentials Magnaporthe grisea Resistance gene Rice blast
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Constructing a Local Folk-belief Knowledge System: A Case Study on Xiangtou in Hebei Province, China
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作者 LI Xiang-zhen 《Journal of Literature and Art Studies》 2014年第11期1000-1006,共7页
In many areas of North China, villagers are more concerned about the specific practice like ritual, rather than ideology when dealing with the relevant belief problems. Therefore, practice is far more important in the... In many areas of North China, villagers are more concerned about the specific practice like ritual, rather than ideology when dealing with the relevant belief problems. Therefore, practice is far more important in the analysis of villagers' belief problems. In everyday life, villagers produce an entire set of local knowledge based on their needs and experience to life, and form various social relationships based on the shared knowledge. Narration and practice are not only the strategies that villagers often use to construct their local knowledge but also the leading ways to produce and inherit it. So it is indispensable to pay attention to the production ways and the practice, which concerning about the local belief knowledge, thus it may be better to understand their inner logic of participating the relevant ritual activities when we analyze xiangtou (香头) and kanxiang (看香) activities widely existed in rural areas of North China. 展开更多
关键词 folk-belief knowledge Xiangtou Kanxiang NARRATION activity
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A new record of Sebastes koreanus from China based on morphological characters and DNA barcoding 被引量:4
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作者 方亚璐 KAI Yoshiaki +2 位作者 YANAGIMOTO Takashi 宋娜 高天翔 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期590-596,共7页
A new record of Sebastes koreanus (Kim and Lee, 1994) was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Sample... A new record of Sebastes koreanus (Kim and Lee, 1994) was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study, specimens had the following morphological characteristics: light brown body with dark stripes and tiny dark spots, 4-5 wide indistinct vertical patterns on the side, 2 radial stripes behind and below the eyes, 1 large dark blotch on the opercle. Additionally, the following meristie characters were recorded: dorsal fin XIV-13, pectoral fin 16, anal fin III-6-7, pelvic fin [-5, lateral line scales 29-30, and vertebrae 26. The fragment of cytochrome oxidase subunit I (CO1) gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other Sebastes species ranged from 3.1% to 7.6%, which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion, evolution, patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research. 展开更多
关键词 Sebastes koreanus coastal waters of northern China new record morphological characters cytochrome oxidase subunit I (CO1)
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Effects of Reed Rootstocks on Hydraulic Properties of Surface Soil in the Shuangtai Estuary Wetland, Northeast China
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作者 Qian Lin Tadaharu Ishikawa +2 位作者 Ryosuke Akoh Fenglin Yang Shushen Zhang 《Journal of Environmental Science and Engineering(A)》 2015年第4期169-176,共8页
A set of field experiments was conducted to investigate the effects of reed rootstocks on hydraulic properties of surface soils in the Shuangtai Estuary Wetland, Northeast China. The soil particle size distribution an... A set of field experiments was conducted to investigate the effects of reed rootstocks on hydraulic properties of surface soils in the Shuangtai Estuary Wetland, Northeast China. The soil particle size distribution and rootstock content were analyzed, and the vertical soil water profile was monitored by using a multisensory capacitance system. Hydraulic conductivity of the surface soil layer was estimated by in si-tu infiltration. The soil was silt loam with less sand; soil texture was consistent though the vertical profile, but bulk density was lower in the upper 20 era, where the fine roots were concentrated. The surface soil moisture profile changed dynamically, and variation in vertically integrated soil moisture was consistent with observed precipitation and estimated evaporation. Infiltration capacity was 30 cm'd"~, much larger than typical hydraulic conductivity values for silt loam with less sand. These findings suggest that fine annual roots change the soil matrix and hydraulic conductivity in surface soils. A vertical one-dimensional water transport model was presented based on Richard's equation. Model parameters were estimated from the soil analyses and literature data. The computation accurately reproduced the dynamic changes in moisture in surface soils containing large volumes of fine rootstock. 展开更多
关键词 Soil moisture reed colony water conductivity field measurement 1-D (one-dimensional) numerical simulation
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