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Interdecadal variability of summer precipitation in the Three River Source Region: Influences of SST and zonal shifts of the East Asian subtropical westerly jet 被引量:1
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作者 Yumeng Liu Xianhong Meng +5 位作者 Lin Zhao S-Y.Simon Wang Lixia Zhang Zhaoguo Li Chan Wang Yingying An 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期47-53,共7页
Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the i... Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer precipitation.Using empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR precipitation.This influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°N.Moreover,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ. 展开更多
关键词 Summer precipitation East Asian subtropical westerly jet Three River Source region Atlantic-Eurasian teleconnection
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Weathering-pedogenesis of Carbonate Rocks and Its Environmental Effects in Subtropical Region 被引量:4
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作者 ZHU Lijun HE Shouyang LI Jingyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第5期982-993,共12页
We investigated the weathering-pedogenesis of carbonate rocks and its environmental effects in subtropical regions of China. The investigation demonstrated that the weathering- pedogenesis of carbonate rocks is the pr... We investigated the weathering-pedogenesis of carbonate rocks and its environmental effects in subtropical regions of China. The investigation demonstrated that the weathering- pedogenesis of carbonate rocks is the process of a joint action of corrosion and illuviation and metasomatism in subtropical region. It is characterized by multi-stage, multi-path and multi-style. With the persisting development of weathering-pedogenesis of carbonate rocks, metasomatic pedogenesis progressively became the main process of the weathering-pedogenesis and the dominant style of formation of minerals. And it proceeds through the whole process of evolution of the weathering-pedogenesis of carbonate rocks. The stage evolution of weathering-pedogenesis of carbonate rocks and the fractionation evolution of newly produced minerals are characterized by obvious vertically zoning structures and the rules of gradation of elements geochemical characteristics in the carbonate rocks weathering profiles. The geochemical process of weathering-pedogenesis of carbonate rocks can be divided into three geochemical evolution stages, i.e., the Ca, Mg-depletion and Si, Al-enrichment stage; the Fe, Mn enrichment stage and the Si-depletion and Al-enrichment stage in the subtropical regions. Consistent with the three geochemical evolution stages, the sequence of formation and evolution of minerals can be divided into the clay mineral stage; the Fe, Mn oxide and the gibbsite stage. The influence of weathering-pedogenesis of carbonate rocks on the chemical forms of heavy elements is mainly affected via newly produced components and minerals in the process of weathering-pedogenesis, e.g., iron oxide minerals and organic matters. The important mechanism for the mobilization, transport and pollution of F and As is affected the selective adsorption and desorption of F and As on the surface of iron oxide minerals in the subtropical karst zones, i.e., the selective adsorption and desorption on mineral surfaces of newly produced minerals in the process of weathering-pedogenesis control the geochemical behavior of elements on the Earth's surface and environmental quality in subtropical regions. 展开更多
关键词 carbonate rocks weathering-pedogenesis metasomatic pedogenesis environmental effects subtropical region
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Fertility Restoration of Red Soils in Low-Hilly Region of Middle Subtropical China 被引量:3
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作者 SUNBO ZHANGTAOLIN 《Pedosphere》 SCIE CAS CSCD 1999年第3期205-212,共8页
There are about 1.27 million ha of upland red soils derived from Quaternary red clay facing the degradation in the low-hilly region of the middle subtropical China. From the aspects of chemistry, physics and microbiol... There are about 1.27 million ha of upland red soils derived from Quaternary red clay facing the degradation in the low-hilly region of the middle subtropical China. From the aspects of chemistry, physics and microbiology, the processes of soil fertility restoration in the surface layer (0~20 cm) under three types of land use patterns (i.e. citrus orchard, tea garden and upland) in two provinces were studied in this work. Results showed that the reclamation of eroded waste land improved most of soil properties. Soil organic matter, total N and P, available P and K, and exchangeable Ca and Mg increased, but soil total K and exchangeable Al decreased. Soil PH decreased by 0.5 unit in the pure tea plantation for 20 years. Soil reclamation increased the percentage of soil microaggregates (<0.25 mm), especially those with a diameter of 0.02~0.002 mm. Soil total porosity increased in the cultivated lands with the increase of soil aeration and capillary porosity. The number of soil microorganisms increased with reclamation caused mainly by the huge increase of the total amount of bacteria. With the cultivation, the activity of soil urease and acid phosphatase increased, but that of invertase dropped. 展开更多
关键词 FERTILITY low-hilly region red soils RESTORATION subtropical China
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Construction of Efficient Multiple Planting Patterns of Potato for Tridimensional Climate in Subtropical Region of China 被引量:4
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作者 黄钢 沈学善 +2 位作者 屈会娟 汤永禄 袁继超 《Agricultural Science & Technology》 CAS 2013年第9期1344-1346,共3页
[Objective] The aim was to make full use of light-heat resources to expand the potato planting area on the base of ensuring the production of main grain crops and the limited arable land. [Methods] Through catch crops... [Objective] The aim was to make full use of light-heat resources to expand the potato planting area on the base of ensuring the production of main grain crops and the limited arable land. [Methods] Through catch crops, multiple cropping and intercropping, new multiple planting patterns of potato with efficiency are constructed, for the purpose of increasing yield and benefit of potato. [Result] In irrigated plain and hill area, three new planting patterns such as autumn potato/rope-rice,winter potato-rice-autumn potato, and autumn(winter) potato-rice were constructed.In dry land of plain and hill area, three new planting patterns such as spring(winter)potato/maize/sweet potato, spring(winter) potato/maize-autumn potato, and wheat + winter potato/maize/sweet potato were constructed. In plateau mountainous area, spring potato/maize was constructed. [Conclusion] With use of new planting patterns, the cropping index of new patterns was 200%-300%, while the accumulated temperature utilization was 68.9%-93.4%, light energy utilization was 0.98%-1.59% and straw utilization was 50%-100%. To compared with traditional planting patterns, the yield increased by 2.6%-93%, and benefit increased by 15.8%-284.3%. Furthermore,multiple planting patterns of potato have become main planting patterns in increasing yield and income in Sichuan. 展开更多
关键词 Tridimensional climate in subtropical region POTATO Planting pattern
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基于“情景-任务-能力”的长三角传染病区域协同处置能力提升
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作者 陈蓉 张放 +2 位作者 管至为 何懿 黄晓燕 《中国卫生资源》 CSCD 北大核心 2023年第6期674-677,共4页
提升传染病区域协同处置能力是深化长三角卫生健康协同发展的重要抓手。卫生应急演练是检验卫生应急体系建设的重要手段。本研究将“情景-任务-能力”的方法引入长三角传染病区域协同处置领域,以构建杭州亚运会测试赛期间发现登革热等... 提升传染病区域协同处置能力是深化长三角卫生健康协同发展的重要抓手。卫生应急演练是检验卫生应急体系建设的重要手段。本研究将“情景-任务-能力”的方法引入长三角传染病区域协同处置领域,以构建杭州亚运会测试赛期间发现登革热等输入传染病病例后区域协查和联动处置情景为例,分析应急处置5个阶段的任务、主要责任单位及任务要点,并以“区域联合风险评估和风险管理”为例,从预案方案、组织领导、人员、设备与系统、物资、培训、演练等7个方面着手,详细分析能力评估的内容。同时,采用“任务分类”的思想,针对属于第二类任务的区域联动涉及的协查、评估和培训等任务,以“区域联合风险评估和风险管理”任务为例,提出制定区域联合风险评估和风险管理协议或方案,成立区域卫生应急专家智库,加强区域公共卫生风险评估交流和统一培训等措施建议。 展开更多
关键词 情景-任务-能力scene-task-ability 应急演练emergency response drill 长三角Yangtze River Delta 区域协同regional collaboration
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Application of Remote Sensing in Study of Slope Land Use and Soil Erosion in Subtropic Region of China 被引量:6
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作者 ZENGZHIYUAN PANXIANZHANG 《Pedosphere》 SCIE CAS CSCD 1997年第3期237-242,共6页
This paper introduces briefly two remote sensing case studies on land use in the subtropic region of China. One is on slope land use in the Yangtze River Three Gorges area. This is a large area of 60497 km2.First of a... This paper introduces briefly two remote sensing case studies on land use in the subtropic region of China. One is on slope land use in the Yangtze River Three Gorges area. This is a large area of 60497 km2.First of all, geometric correction and supervised classification were conducted for ten scenes of Landsat-5 TM or MSS images. The resolution of the processed images is 50 m ×50 m on ground. By the classification the land use/cover categories in this area were discriminated. Then the croplands including rice fields and upland fields were extracted from the land use/cover maps. Simultaneously the slope grade maps were prepared based on the topographic maps. Overlaying the slope grade maps and the cropland maps, the area and percentage of the croplands in different slope grades were determined. This case study indicated that 71.5% of the uplands was situated on the slope above 15° and 25% on the slope above 25° in this area. It is dangerous, and urgent cultivation or engineering measures should be taken. Another case study is on soil erosion in Linshan County of Guangxi Province. Airphoto interpretation and supervised classification of a Landsat TM image were carried out for discriminating land cover/use categories in an area of 3557.8 km2.And the soil erosion intensity grades were determined according to the land cover/use maps and slope maps.It wed discovered that the land suffering soil erosion accounted for 2404.0 km2, 67.6% of the total area of the county. Necessary measures to control soil erosion should be taken also. 展开更多
关键词 land use remote sensing soil erosion subtropic region
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16-23S rRNA Spacer Region Polymorphism in Gangetic River Water Isolates of Salmonella
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作者 Rubi Singh Mumtesh Kumar Saxena 《Journal of Water Resource and Protection》 2010年第8期756-761,共6页
Salmonella is one of the major pathogenic bacteria present in contaminated water. 16-23S rRNA spacer region has been reported to be polymorphic at serovar level in Salmonella. Salmonella isolates obtained from Ganges ... Salmonella is one of the major pathogenic bacteria present in contaminated water. 16-23S rRNA spacer region has been reported to be polymorphic at serovar level in Salmonella. Salmonella isolates obtained from Ganges river water were studied for 16-23S rRNA spacer region polymorphism. Thirty three isolates belonging to eight serovars (S. Typhimurium, S. Abuja, S. Pantypridd, S. Lagos, S. Chinkual, S. Zwickau, S. Goldenberg and S. Oritamerin) were studied for the polymorphism. Out of 33 isolates, 15 different profiles were observed no serovar specific profile. Our findings indicate that 16-23S rRNA spacer region is not specific at serovar level, but can be used for differentiation of different Salmonella isolates. 展开更多
关键词 GANGES River SALMONELLA SPACER region POLYMORPHISM 16-23s RRNA
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A Search for High-velocity Gas Associated H_2O Masers and Ultracompact HII Regions
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作者 YeXu Dong-RongJiang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2001年第1期60-65,共6页
With the objective of studying the relationships between high-velocity gas and water maser emissions the results of a search from 95 IRAS sources for high-velocity gas associated with star forming molecular clouds are... With the objective of studying the relationships between high-velocity gas and water maser emissions the results of a search from 95 IRAS sources for high-velocity gas associated with star forming molecular clouds are reported. 21 sources have been identified as molecular outflow candidates. 展开更多
关键词 HII regions - ISM: jets and outflows - stars: formation - masers
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Genetic Variation among Fragmented Populations of Atriplex halimus L. Using Start Codon Targeted (SCoT) and ITS1-5.8S-ITS2 Region Markers
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作者 Asmaa Elframawy Hisham Deif Ranya El-Bakatoushi 《American Journal of Molecular Biology》 2016年第2期101-115,共15页
Two forms of A. halimus shrubs: erect habit (A. halimus) and bushy habit shrub (A. schweinfurthii) are used naturally isolated by a considerable distance from each other and occupy the same area. To explore the effect... Two forms of A. halimus shrubs: erect habit (A. halimus) and bushy habit shrub (A. schweinfurthii) are used naturally isolated by a considerable distance from each other and occupy the same area. To explore the effect of natural isolation on the genetic basis of the two forms, Start Codon Targeted (SCoT) and the phylogenetic relationships of A. halimus by sequencing ITS1-5.8S-ITS2 regions of the ribosomal DNA are used. Significant isolation-by-distance relationship was found (r = 0.62, P = 0.001). Soil factors did not influence molecular variations. The natural isolation of A. halimus habitats restricts gene flow among the populations and the observed high within-population genetic diversity (74.19%) in this species is best explained by its outcrossing behaviour, long-lived individuals and overlapping generations. The UPGMA analysis of the SCoT results showed that all the studied populations were divided into two discrete genetic groups with significant separation of the two forms in Burg El-Arab area (Populations 1 and 2) and insignificant separation between two forms in El-Hammam area (population 5 and 6). The sequencing of the ITS1-5.8S-ITS2 rDNA regions also showed the insignificant separation of the two A. halimus forms. We conclude that gene flow depending on habitat fragmentation was the main factor affecting the population genetic differentiation. We suggest that the two forms do not merit specific rank in presence of interference between the two forms and absence of a breeding barrier fail to separate the different populations when they become sympatric. 展开更多
关键词 Atriplex halimus SCoT ITS1-5.8S-ITS2 rDNA regions Atriplex schweinfurthii
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A New Interpretation of the Bipolar HII Region S106 from HCN J = 3 - 2 Mapping Observations
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作者 Sheng-LiQin Jun-JieWang +1 位作者 GangZhao MartinMiller 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第1期1-5,共5页
The first mapping observations of the bipolar HII region S106 in HCN J = 3 - 2 line were made by KOSMA submillimeter telescope in April, 2004. The results show that there is a bipolar outflow centered on the high-mass... The first mapping observations of the bipolar HII region S106 in HCN J = 3 - 2 line were made by KOSMA submillimeter telescope in April, 2004. The results show that there is a bipolar outflow centered on the high-mass star S106 IRS4 and that the flat structure of molecular cloud core is perpendicular to the axis of the outflow. This image roughly corresponds to the optical image where a dark lane bisects the bipolar HII region. Together with the optical, infrared and radio data, we conclude that the central UC HII region and molecular outflow formed before the two lobes of the bipolar HII region, and that a neutral disk is responsible for the bipolar HII region and the outflow. 展开更多
关键词 ISM: clouds - nebulae: HII region - star: formation - individual: S106
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A multiwavelength study of the star forming HⅡ region Sh2-82
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作者 Nai-Ping Yu Jun-Jie Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第6期651-660,共10页
Based on a multiwavelength study, the interstellar medium and young stel- lar objects (YSOs) around the H II region Sh2-82 have been analyzed. Two molecular clumps were found from the archival data of the Galactic R... Based on a multiwavelength study, the interstellar medium and young stel- lar objects (YSOs) around the H II region Sh2-82 have been analyzed. Two molecular clumps were found from the archival data of the Galactic Ring Survey, and using the Two Micron All-Sky Survey catalog, we found two corresponding young clusters embedded in the molecular clumps. The very good relations between CO emission, infrared shells and YSOs suggest that it is probably a triggered star formation region from the expansion of Sh2-82. We further used the data from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire from Spitzer to study the YSOs within the two clumps, confirming star formation in this region. By spectral energy distribution fits to each YSO candidate with infrared excess, we derived the slope of the initial mass function. Finally, comparing the H II region's dynamical age and the fragmenta- tion time of the molecular shell, we discard the "collect and collapse" process as being the triggering mechanism for YSO formation. Sh2-82 can be a mixture of other pro- cesses such as radiative-driven implosion and/or collisions with pre-existing clumps. 展开更多
关键词 ISM: clouds -- nebulae: HII region -- individual: Sh2-82 -- stars:formation
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Sheet 1 China's I/E of Textile & Apparel by Country & Region 2011.1-9
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《China Textile》 2011年第11期62-63,F0004,共3页
关键词 EU Apparel by Country region 2011.1-9
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Activation of metabotropic glutamate receptor 1 regulates hippocampal CA1 region excitability in rats with status epilepticus by suppressing the HCN1 channel
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作者 Xiao-Dan Luo Tao Xiang +3 位作者 Si-Jun Li Mei-Gang Ma Mei-Ling Chen Yuan Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第3期594-602,共9页
Dysregulation of hyperpolarization-activated cyclic nucleotide-gated cation(HCN)channels alters neuronal excitability.However,the role of HCN channels in status epilepticus is not fully understood.In this study,we est... Dysregulation of hyperpolarization-activated cyclic nucleotide-gated cation(HCN)channels alters neuronal excitability.However,the role of HCN channels in status epilepticus is not fully understood.In this study,we established rat models of pentylenetetrazole-induced status epilepticus.We performed western blot assays and immunofluorescence staining.Our results showed that HCN1 channel protein expression,particularly HCN1 surface protein,was significantly decreased in the hippocampal CA1 region,whereas the expression of HCN2 channel protein was unchanged.Moreover,metabolic glutamate receptor 1(mGluR1)protein expression was increased after status epilepticus.The mGluR1 agonist(RS)-3,5-dihydroxyphenylglycine injected intracerebroventricularly increased the sensitivity and severity of pentylenetetrazole-induced status epilepticus,whereas application of the mGluR1 antagonist(+)-2-methyl-4-carboxyphenylglycine(LY367385)alleviated the severity of pentylenetetrazole-induced status epilepticus.The results from double immunofluorescence labeling revealed that mGluR1 and HCN1 were co-localized in the CA1 region.Subsequently,a protein kinase A inhibitor(H89)administered intraperitoneally successfully reversed HCN1 channel inhibition,thereby suppressing the severity and prolonging the latency of pentylenetetrazole-induced status epilepticus.Furthermore,H89 reduced the level of mGluR1,downregulated cyclic adenosine monophosphate(cAMP)/protein kinase A expression,significantly increased tetratricopeptide repeat-containing Rab8b-interacting protein(TRIP8b)(1a-4)expression,and restored TRIP8b(1b-2)levels.TRIP8b(1a-4)and TRIP8b(1b-2)are subunits of Rab8b interacting protein that regulate HCN1 surface protein. 展开更多
关键词 (RS)-3 5-dihydroxyphenylglycine CA1 region EXCITABILITY H89 HCN1 channel LY367385 MGLUR1 PENTYLENETETRAZOLE status epilepticus
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Table 1.FDI flows,by region and selected countries,1994-2005
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《China Textile》 2006年第4期7-7,共1页
关键词 FDI Table 1.FDI flows by region and selected countries 1994-2005
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China's I/E of Textile & Apparel by country/region[1-4 2007]
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《China Textile》 2007年第6期59-59,共1页
关键词 Apparel by country/region[1-4 2007
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热区葡萄育种研究进展
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作者 王博 郭荣荣 +7 位作者 成果 韩佳宇 林玲 何建军 白扬 谢蜀豫 王举兵 白先进 《南方农业学报》 CAS CSCD 北大核心 2024年第8期2374-2385,共12页
葡萄是温带果树,葡萄生产及新品种培育主要分布在气候干燥凉爽的温带地区。随着避雨、破眠、一年两收等葡萄栽培新技术的推广,热区葡萄由于早熟、错季经济效益明显,近年发展迅猛,该区已成为我国特色优势栽培区。葡萄新品种对葡萄产业的... 葡萄是温带果树,葡萄生产及新品种培育主要分布在气候干燥凉爽的温带地区。随着避雨、破眠、一年两收等葡萄栽培新技术的推广,热区葡萄由于早熟、错季经济效益明显,近年发展迅猛,该区已成为我国特色优势栽培区。葡萄新品种对葡萄产业的快速发展起着重要推动作用。文章结合国内外研究进展提出热区葡萄育种的必要性,概述当前热区葡萄产业现状、主栽葡萄品种及存在问题:由于我国热区葡萄育种工作起步较晚,目前热区主栽葡萄品种仍为温带地区育成,均不耐湿热,存在着色障碍、品质下降、抗性差、易感多种病虫害、需冷量较高、发芽不整齐和易发生日灼等“水土不服”问题。文章分析了热区育种的优势:热区积温高,实生苗生长量大,结果早,育种效率高;热区分布的野生耐热葡萄资源丰富,是培育耐热抗性强新品种的宝贵材料;热区逆境条件可为耐热抗病葡萄新品种的选育提供天然的筛选环境。总结湿热地区葡萄育种研究进展,包括葡萄栽培技术基础、育种机构和专业技术人才队伍情况。阐述广西葡萄种质资源引进与评价的基础,介绍巴西热区葡萄遗传育种研究计划的代表性新品种及广西热区葡萄选育品种的登记及保护情况,并提出我国热区葡萄育种下一步工作计划。在高热高湿、降雨多、日照时数少、冬季低温时数少的热区逆境气候环境下选育早熟优质、抗性强、易栽培和耐储运葡萄新品种是热区葡萄产业健康高质量可持续发展的保障,对提升热区葡萄新质生产力具有重要意义。 展开更多
关键词 热区 逆境 葡萄 育种 优势 进展
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浙江省丽水市亚热带森林景观格局对森林碳密度的影响
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作者 王剑武 季碧勇 +1 位作者 王铮屹 朱程昊 《浙江农林大学学报》 CAS CSCD 北大核心 2024年第1期30-40,共11页
【目的】定量分析浙江省丽水市亚热带森林景观格局对森林碳密度的影响,为开展森林经营、生态保护修复以提高亚热带森林碳汇功能提供理论依据。【方法】基于省级固定样地数据,使用生物量模型和含碳率测算样地的森林碳密度,再通过普通Krig... 【目的】定量分析浙江省丽水市亚热带森林景观格局对森林碳密度的影响,为开展森林经营、生态保护修复以提高亚热带森林碳汇功能提供理论依据。【方法】基于省级固定样地数据,使用生物量模型和含碳率测算样地的森林碳密度,再通过普通Kriging插值形成区域森林碳密度分布图,并分析森林碳密度的空间自相关特征。选取5项景观格局指标和3项自然因素,利用多尺度地理加权回归(MGWR)模型探讨森林景观格局对森林碳密度的影响,并分析影响结果的空间非平稳性。【结果】2012—2019年,丽水市森林平均碳密度从23.19 t·hm^(−2)上升到31.96 t·hm^(−2),且空间分布呈显著的正空间自相关性。森林景观格局显著影响森林碳密度,并表现不同尺度效应,影响程度在空间上也存在差异。景观蔓延度和斑块密度对森林碳密度驱动力较大,而景观最大斑块指数的驱动力较小。【结论】森林景观格局对森林碳密度的影响表现较为明显的空间异质性,应地制宜制定森林经营管理政策,实施自然演替和人工干预相结合的生态系统保护修复工程。 展开更多
关键词 森林景观格局 森林碳密度 多尺度地理加权回归 影响因素 亚热带丘陵区 丽水市
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Vegetation-Climate Relationship and Its Application in the Division of Vegetation Zone in China 被引量:38
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作者 方精云 宋永昌 +1 位作者 刘鸿雁 朴世龙 《Acta Botanica Sinica》 CSCD 2002年第9期1105-1122,共18页
Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundat... Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundation for understanding the vegetation distribution and theoretically serving vegetation regionalization. Vegetation regionalization is a theoretical integration of vegetation studies and provides a base for physiogeographical regionalization as well as agriculture and forestry regionalization. Based on a brief historical overview on studies of vegetation_climate relationships and vegetation regionalization conducted in China, we review the principles, bases and major schemes of previous vegetation regionalization and discuss on several contentious boundaries of vegetation zones in the present paper. We proposed that, under the circumstances that the primary vegetation has been destroyed in most parts of China, the division of vegetation zones/regions should be based on the distribution of primary and its secondary vegetation types and climatic indices that delimit distribution of the vegetation types. This not only reveals the closed relationship between vegetation and climate, but also is feasible practically. Although there still are divergence of views on the name and their boundaries of the several vegetation zones, it is commonly accepted that there are eight major vegetation regions in China, i.e. cold temperate needleleaf forest region, temperate needleleaf and broadleaf mixed forest region, warm temperate deciduous broadleaf forest region, subtropical evergreen broadleaf forest region, tropical monsoon forest and rain forest region, temperate steppe region, temperate desert region, and Qinghai_Xizang (Tibetan) Plateau high_cold vegetation region. Analyzing characteristics of vegetation and climate of major vegetation boundaries, we suggested that: 1) Qinling Mountain_Huaihe River line is an important arid/humid climatic, but not a thermal climatic boundary, and thus can not also be regarded as the northern limit of the subtropical vegetation zone; 2) the northern limit of subtropical vegetation zone in China is along the northern coast of the Yangtze River, from Hangzhou Bay, via Taihu Lake, Xuancheng and Tongling in Anhui Province, through by southern slope of the Dabie Mountains, to Wuhan and its west, coinciding with a warmth index ( WI ) value of 130-140 ℃·month; 3) the tropical region is limited in a very small area in southeastern Hainan Island and southern edge of Taiwan Island; and 4) considering a significant difference in climates between the southern and northern parts of the warm temperate zone, we suggested that the warm temperate zone in China is divided into two vegetation regions, deciduous broadleaf woodland region and deciduous and evergreen broadleaf mixed forest region, the Qinling Mountain_Huaihe River line being as their boundary. We also claimed that the zonal vegetation in North China is deciduous broadleaf woodland. Finally, we emphasized the importance of dynamic vegetation regionalization linked to climate changes. 展开更多
关键词 China dynamic vegetation regionalization arid/humid climate northern limit of subtropical zone Qinling Mountain_Huaihe River line thermal climate vegetation_climate relationship vegetation regionalization vegetation zone
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石栎-青冈常绿阔叶林土壤有机碳和全氮空间变异特征 被引量:19
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作者 杨丹 项文化 +4 位作者 方晰 樊纲惟 许玉庆 文丽 邹丽梅 《生态学报》 CAS CSCD 北大核心 2014年第12期3452-3462,共11页
在1hm2(100 m×100 m)石栎(Lithocarpus glaber)-青冈(Cyclobalanopsis glauca)常绿阔叶林内100个10 m×10 m小样方的中心位置,按0—10 cm、10—20 cm和20—30 cm土层采集土壤样品,测定土壤有机碳(C)和全氮(N)含量。基于区域化... 在1hm2(100 m×100 m)石栎(Lithocarpus glaber)-青冈(Cyclobalanopsis glauca)常绿阔叶林内100个10 m×10 m小样方的中心位置,按0—10 cm、10—20 cm和20—30 cm土层采集土壤样品,测定土壤有机碳(C)和全氮(N)含量。基于区域化变量理论和地质统计软件(GS+Version 9)的空间分析功能,应用地统计学的半方差函数定量研究该常绿阔叶林土壤有机C和全N的空间变异特征。结果表明:该林地土壤有机C含量平均值为18.61 g/kg,变化范围为9.53—39.40 g/kg,全N含量平均值为1.63g/kg,变化范围为0.73—3.32 g/kg。土壤有机C半方差函数的理论模型符合球状模型,全N半方差函数的理论模型符合高斯模型。土壤有机C和全N的空间异质性主要是由结构性因素引起的,且空间自相关程度均为中等程度。分形维数反映了有机C和全N空间格局差异及尺度依赖特征,有机C分形维数较大,空间格局比全N略为复杂。采用Kriging插值方法,1hm2森林内土壤有机C和全N具有相似的空间分布格局,呈现明显的条带状和斑块状的梯度变化。土壤有机C含量与海拔、凹凸度呈负相关,但相关性不显著,与林地凋落物量呈极显著正相关。土壤全N含量与海拔、凹凸度呈显著负相关,与林地凋落物量呈正相关,反映出土壤N的淋溶特性。 展开更多
关键词 地统计学 土壤有机碳 土壤养分 空间异质性 亚热带 常绿阔叶林
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云南北中亚热带植烟区土壤养分的空间分布特征与肥力质量评价
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作者 钱颖颖 马翔 +7 位作者 夏建军 王萝萍 刘馨芮彤 张志明 闫辉 李枝武 倪明 王炽 《西南农业学报》 CSCD 北大核心 2024年第9期2077-2085,共9页
【目的】云南北中亚热带气候区烤烟与其它作物种植区域交错重叠。明确该气候区植烟土壤的肥力空间变异特征,为该区作物养分管理和土壤肥力调控提供技术支持。【方法】以2019年云南北中亚热带2548个植烟土壤样品为研究对象,采用模糊数学... 【目的】云南北中亚热带气候区烤烟与其它作物种植区域交错重叠。明确该气候区植烟土壤的肥力空间变异特征,为该区作物养分管理和土壤肥力调控提供技术支持。【方法】以2019年云南北中亚热带2548个植烟土壤样品为研究对象,采用模糊数学模型隶属函数法对土壤肥力质量进行综合评价,运用主成分分析法确定各指标的权重和造成肥力差异的主控因子,并通过GIS空间插值确定土壤肥力质量指数的空间分布特征。【结果】云南北中亚热带植烟区土壤肥力质量指数平均值为0.65,处于较高肥力水平。土壤SOM、TN、AP和AK的变异系数分别为46.84%、48.69%、75.64%和52.34%,均属于中等变异强度,且含量较为丰富。土壤AP是影响土壤肥力差异的主要限制因子。云南北中亚热带植烟区土壤肥力质量指数呈中部高,东部或西部部分区域低的分布格局,局部地区有零星分布。【结论】云南北中亚热带植烟区土壤较适宜烟草生长。平衡施肥时应注意控制氮肥,增施有机肥和磷钾肥,有效平衡并协调土壤养分,提高植烟区土壤肥力和烟叶品质。 展开更多
关键词 北中亚热带 植烟区土壤 土壤养分 土壤肥力 质量评价
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