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The Homogeneity of Distributional Patterns of the Global Terrestrial Animal,Plant and Microorganism under the Influence of Ecological Conditions 被引量:2
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作者 Shen Qi Lu Jiqi +2 位作者 You Zhixing Ren Yingdang Shen Xiaocheng 《Journal of Environmental Science and Engineering(A)》 2022年第4期121-137,共17页
The world animal geographical regionalization scheme and the plant geographical regionalization scheme have been formulated by zoologists and botanists respectively since the biogeography has been established.This res... The world animal geographical regionalization scheme and the plant geographical regionalization scheme have been formulated by zoologists and botanists respectively since the biogeography has been established.This research team initially confirmed the homogeneity of Chinese animal and plant geography.To explore the relationship between the distribution pattern of global animals,plants,and microorganisms,global 141,814 genera of terrestrial animals,17,526 genera of plants,21,321 genera of microorganisms,and their major taxa were analyzed using their proposed SGF(Similarity General Formula)and a new multivariate similarity clustering analysis method.Almost identical analytical results were obtained,meeting the requirements of statistics,geography,ecology and biology respectively.The expected consistency of their distribution pattern was achieved for the first time.We prove that the earth’s ecological conditions affect the homogeneity and accumulation of the distribution of animals,plants and microorganisms.Homogeneity determines the distribution pattern of global kinds of biological consistency,accumulation determines the impact of the evolutionary period on the breadth of distribution,microorganisms appear earliest,plants second,animals later,and their average distribution domain decreases in turn,reflecting these differences.Therefore,this study not only provides a theoretical basis and quantitative basis for the establishment of geographical regionalization scheme but also advances the development of biogeography to a new stage and raises the theory of biogeographic analysis to a new height. 展开更多
关键词 Distribution pattern clustering analysis terrestrial biology HOMOGENEITY geographical regionalization
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The spatial distributional pattern of seed plants and its future advances
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作者 Jun Wen 《Journal of Integrative Plant Biology》 2025年第10期2529-2531,共3页
The geographic distribution of organisms has been a central theme in biology since the time of Darwin and Wallace(Darwin,1859;Wallace,1876;Good,1974;Raven and Axelrod,1974;Wen et al.,2013).As biogeography advances,inc... The geographic distribution of organisms has been a central theme in biology since the time of Darwin and Wallace(Darwin,1859;Wallace,1876;Good,1974;Raven and Axelrod,1974;Wen et al.,2013).As biogeography advances,increasing attention has been paid to understanding distributional patterns and the processes shaping them(Wen et al.,2010;Ficetola et al.,2017;You et al.,2024). 展开更多
关键词 seed plants geographic distribution BIOGEOGRAPHY understanding distributional patterns shaping processes geographic distribution organisms spatial distribution distributional patterns
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Vascular plant diversity and distribution pattern in Tajikistan:A global hotspot of diversity
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作者 ZHOU Yixin MA Suliya +7 位作者 LI Wenjun Parvina KURBONOVA Mariyo BOBOEV LI Yufan Hikmat HISORIEV MA Keping YANG Weikang ZHANG Yuanming 《Regional Sustainability》 2026年第1期37-53,共17页
Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges... Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges.There has been a lack of a comprehensive and multidimensional assessment to inform strategic conservation planning.Therefore,this study integrated 4 key biodiversity indices including species richness(SR),phylogenetic diversity(PD),threatened species richness(TSR),and endemic species richness(ESR)to map species diversity distribution patterns,identify conservation gaps,and elucidate their effects of climatic factors.This study revealed that species diversity shows a clear trend of decreasing from the western region to the eastern region of Tajikistan.The central–western mountains(specifically the Gissar-Darvasian and Zeravshanian regions)emerge as irreplaceable biodiversity hotspots.However,we found a severe spatial mismatch between these priority areas and the existing protected areas(PAs).Protection coverage for all hotspots was alarmingly low,ranging from 31.00%to 38.00%.Consequently,a critical 64.80%of integrated priority areas fall outside of the current PAs,representing a major conservation gap.This study identified precipitation seasonality and isothermality as the principal drivers,collectively explaining over 50.00%of the diversity variation and suggesting high vulnerability to hydrological shifts.Furthermore,we detected significant geographic sampling bias in the public biodiversity databases,with the most critical hotspot being systematically under-sampled.This study provides a robust scientific basis for conservation action,highlighting the urgent need to strategically expand PAs in the under-protected southwestern region and to mitigate critical sampling gaps through targeted data digitization and field surveys.These measures are indispensable for securing Tajikistan’s unique biodiversity and achieving the Kunming-Montreal Global Biodiversity Framework Target 3(“30×30 Protection”). 展开更多
关键词 Vascular plant Species diversity Distribution pattern Conservation gaps TAJIKISTAN
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Distributional patterns of anemophilous tree pollen indicating the pathways of Indian monsoon through QinghaieTibetan Plateau 被引量:1
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作者 Zhi-Yong Zhang Cheng-Sen Li 《Journal of Palaeogeography》 SCIE CSCD 2017年第4期352-358,共7页
The distribution pattern of vegetation on QinghaieTibetan Plateau is fundamentally influenced by the plateau climate, which is mainly controlled by Indian monsoon during summer. The long distance transportation of pol... The distribution pattern of vegetation on QinghaieTibetan Plateau is fundamentally influenced by the plateau climate, which is mainly controlled by Indian monsoon during summer. The long distance transportation of pollen(mostly anemophilous taxa) produced by trees on the plateau has been recorded by modern pollen samples in previous studies, and hypothesized to be a good indicator of monsoon dynamics.Here we use 270 surface pollen samples from QinghaieTibetan Plateau to test the distribution patterns of the anemophilous tree pollen. Meanwhile factors related to Indian monsoon affecting pollen transportation are simulated and analyzed. Results show that depositional patterns of anemophilous tree pollen, especially Abies, Pinus, Quercus and Betula are completely controlled by the pathways of Indian monsoon. This is reflected by climatic indicators of the atmospheric pressure pattern over JuneeJ ulye August, by the precipitation pattern over JuneeJulyeAugust and by the topographic feature of the plateau. The spatial interpolation of thin plate spline results also display two depositional centers(ca. 30°N, 95°E and 30°N, 105°E)of the anemophilous tree pollen. In contrast to previous conclusion that pollen distributional pattern is determined by mean annual precipitation, we argue that Indian monsoon is the essential controller because of the synchronization between timing of monsoon wind and timing of plants flowering. Our finding strongly suggests that distributional pattern of anemophilous tree pollen on the plateau is a good proxy of Indian monsoon. 展开更多
关键词 distributional patterns Anemophilous tree pollen Indian monsoon QinghaieTibetan Plateau Quaternary
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Identification and distribution patterns of the ultra-deep small-scale strike-slip faults based on convolutional neural network in Tarim Basin,NW China 被引量:1
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作者 Hao Li Jun Han +4 位作者 Cheng Huang Lian-Bo Zeng Bo Lin Ying-Tao Yao Yi-Chen Song 《Petroleum Science》 2025年第8期3152-3167,共16页
The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set inco... The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set incorporating innovative fault labels to train a U-Net-structured CNN model,enabling effective identification of small-scale strike-slip faults through seismic data interpretation.Based on the CNN faults,we analyze the distribution patterns of small-scale strike-slip faults.The small-scale strike-slip faults can be categorized into NNW-trending and NE-trending groups with strike lengths ranging 200–5000 m.The development intensity of small-scale strike-slip faults in the Lower Yingshan Member notably exceeds that in the Upper Member.The Lower and Upper Yingshan members are two distinct mechanical layers with contrasting brittleness characteristics,separated by a low-brittleness layer.The superior brittleness of the Lower Yingshan Member enhances the development intensity of small-scale strike-slip faults compared to the upper member,while the low-brittleness layer exerts restrictive effects on vertical fault propagation.Fracture-vug systems formed by interactions of two or more small-scale strike-slip faults demonstrate larger sizes than those controlled by individual faults.All fracture-vug system sizes show positive correlations with the vertical extents of associated small-scale strike-slip faults,particularly intersection and approaching fracture-vug systems exhibit accelerated size increases proportional to the vertical extents. 展开更多
关键词 Small-scale strike-slip faults Convolutional neural network Fault label Isolated fracture-vug system Distribution patterns
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Sedimentary Structure Characteristics and Spatial Distribution Pattern of the Zhaoji Salt Mine Derived from Dense Array Ambient Noise Tomography
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作者 Hongwei Wang Xiaofeng Tian +5 位作者 Qiaoxia Liu Jia Cheng Ming Zhou Zhiping Xu Jiyan Lin Shuaipeng Zhu 《Journal of Earth Science》 2025年第5期2094-2108,共15页
Due to the lack of the three-dimensional structure of the Zhaoji Salt Basin,the salt mining enterprises have obvious clustering when choosing sites.Production capacity declines rapidly as mining deepens,and the enterp... Due to the lack of the three-dimensional structure of the Zhaoji Salt Basin,the salt mining enterprises have obvious clustering when choosing sites.Production capacity declines rapidly as mining deepens,and the enterprises are entering a stage of stagnation in production.In this study,a dense seismic array of 125 short-period stations was deployed around the core mining area and its vicinity of the salt mine industry,we used the ambient noise tomography(ANT)method to image the three-dimensional shear wave velocity structure at the depth shallower than 3 km.The results indicate:(1)The overall shear wave velocity in the study area is relatively lower,ranging from 0.8 to 1.8 km/s,which could be related to the loose and thick deposition of the Zhaoji sub-depression.(2)The three-dimensional shear wave velocity structure reveals that the sedimentary thickness of the Zhaoji sub-depression is deeper in the southeast and shallower in the northwest,with the sedimentary center located around Heping Town and Dahuangzhuang Town.(3)The Zhaoji salt mine is a low-velocity anomalous zone in the shear wave velocity structure with an inverse‘C'character spreading along Nanchenji Town and Zhaoji Town,with a depth ranging from approximately 1.2 to 2.8 km,it may be caused by the development of rock fissures due to water extraction and injection.The surrounding rock exhibits relatively high velocity,which reflects the morphological characteristics of the Zhaoji Salt Basin.The three-dimensional shear wave velocity model obtained in this study provides scientific guidance for the industrial exploitation of the Zhaoji salt mine and reference for salt exploration of the Hongze Salt Basin.It also provides an important basis for the seismic risk assessment of the salt basins.Simultaneously,it holds significant implications for exploring the application of ambient noise tomography method in spatial detection of salt mine belt. 展开更多
关键词 ambient noise tomography Zhaoji salt mine group velocity velocity structure sedimentary structure distribution pattern SEDIMENTOLOGY mineral deposits
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Stranding and sighting events reveal distribution patterns and potential threats to finless porpoises in the Qiantang River Estuary,China
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作者 Dongzi Pan Ying Li 《Acta Oceanologica Sinica》 2025年第5期56-67,共12页
Finless porpoises(FPs)serve as flagship species and key ecological indicators for assessing environmental quality.However,FPs are challenging to survey due to their elusive behavior and lack of distinctive features.St... Finless porpoises(FPs)serve as flagship species and key ecological indicators for assessing environmental quality.However,FPs are challenging to survey due to their elusive behavior and lack of distinctive features.Stranding and sighting events offer essential information on species diversity,distribution patterns,and potential threats.In this study,records from 1986 to 2023 were analyzed to assess the temporal and spatial distribution patterns of FP strandings and sightings in the Qiantang River Estuary,China.Results show an increase in the number of recorded events over time.Seasonal variations were evident,with a peak in strandings and sightings occurring in late winter.The frequency of records was higher during spring and moderate tides compared to neap tides,particularly in hydrologically normal years.Rapidly receding tides and sediment accumulation appear to restrict the activity space of FPs,thereby increasing the frequency of these events.Localized conditions associated with stranding and sighting events were classified into four categories:bifurcation zones,confluence zones,separation zones,and deep channels adjacent to concave banks.Deep channels,which are optimal for shipping,also elevate the risk of FP strandings.These findings offer valuable insights for the development and design of conservation strategies tailored to the needs of FPs in estuarine environments. 展开更多
关键词 finless porpoise distribution patterns STRANDINGS flagship species marine environment ecological indicator
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Patterns and Influencing Mechanism of Plant Species Richness of Carexdominated Wetlands in China
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作者 MENG Jingci WANG Guodong +8 位作者 GUO Yue ZHAO Meiling HU Nanlin YUAN Yusong ZHAO Yantong CHEN Qi REN Zhibin LIU Bo JIANG Ming 《Chinese Geographical Science》 2025年第6期1444-1455,共12页
Determining the pattern and mechanisms of species richness distribution at large spatial scales has been one of the core objectives in the field of ecology and biogeography.Although climate and soil effects on terrest... Determining the pattern and mechanisms of species richness distribution at large spatial scales has been one of the core objectives in the field of ecology and biogeography.Although climate and soil effects on terrestrial ecosystems are well-documented,largescale patterns in wetlands are poorly understood due to their unique hydrological processes and vegetation types.Here,we explored the pattern of plant species richness of Carex-dominated wetlands and its influencing mechanism in China based on a national field vegetation survey at 120 sites.Results showed that the community type and plant species richness of Carex-dominated wetlands differed significantly among different climate zones in China.The hierarchical partitioning analysis showed that community type and environmental context(spatial location,water regime,climate and soil conditions)together explained 41%of the variations in plant species richness,and community type had the greatest influence on species richness.Partial Least Squares Path Modeling result showed that plant species richness was directly affected by community type,climate factors,soil properties and water regime.Soil properties and water regime also indirectly affected plant species richness by directly affecting community type.These findings help us understand the pattern of plant diversity distribution in wetlands at large spatial scales and design effective conservation strategies for these valuable sedge meadow wetlands in a changing environment. 展开更多
关键词 species richness Carex wetland distribution pattern community type environmental change
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Spatiotemporal distribution patterns and exploration implications of multi-type coal-measure gases in the Daniudi gas field,Ordos Basin,China
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作者 Zhenrui Bai Fengcun Xing Zengqin Liu 《Energy Geoscience》 2025年第3期133-142,共10页
Coal-measure gas is a primary target with significant potential for the exploration of unconventional hydrocarbon resources.However,the spatiotemporal distribution and combination patterns of multi-type coal-measure g... Coal-measure gas is a primary target with significant potential for the exploration of unconventional hydrocarbon resources.However,the spatiotemporal distribution and combination patterns of multi-type coal-measure gases are yet to be clarified,directly impeding the sweet spot evaluation and exploration deployment of coal-measure gas.This study discussed the characteristics and distribution patterns of coal-measure gases in the Daniudi gas field in northeastern Ordos Basin,China,with abundant drilling data.The results indicate that the coal seams variably thin upward and are mainly seen in the first and second members of the Taiyuan Formation(also referred to as the Tai 1 and Tai 2 members,respectively)and the first member of the Shanxi Formation(Shan 1 Member).Nos.8,5 and 3 coal seams are laterally continuous,and significantly thicker in its southern part compared to the northern part.Moreover,carbonaceous mudstones and shales are better developed in the southern part,where limestones are only observed in the Tai 1 Member.Based on the main lithological types,we identified three lithologic roofs of coal seams,that is,limestone,mudstone,and sandstone,which determine the spatiotemporal distribution of coal-measure gases.Besides bauxite gas in the Benxi Formation,the coal-measure gases include tight-sand gas,coalbed methane(CBM),coal-measure shale gas,and tight-limestone gas,with CBM typically associated with coal-measure shale gas.The combinations of different types of coal-measure gas vary across different layers and regions.Tight-sand gas is well-developed in areas where tight sandstones are in contact with coal-measures.From the Taiyuan to the Shanxi formations,CBM gradually transitions into a combination of CBM and coal-measure shale gas,and coal-measure shale gas.Nos.8 and 5 coal seams in low-lying areas exhibit favorable gas-bearing properties due to their large thickness and favorable roof lithologies,serving as prospective play fairways.Mudstone and limestone roofs are more conducive to achieving good gas-bearing properties.The direct contact between sandstones and coal seams tends to result in the formation of tight-sand gas and a reduced gas content of CBM.While focusing on single types of gas reservoirs such as CBM and tight-sand gas,it is essential to consider the concurrent exploration of various coal-measure gas combinations to discover more additional gas resources and guide exploration deployment. 展开更多
关键词 Coal-measure gas Coal-measure shale gas Coalbed methane(CBM) Tight-sand gas Lithologic assemblage Distribution pattern of gas reservoirs
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Spatiotemporal distribution patterns of macrobenthic communities and their relationship with environmental factors in the Shengsi Archipelago(Zhejiang,China)
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作者 Lingxiang Jin Yibo Liao +6 位作者 Peisong Yu Yanbin Tang Qinghe Liu Rongliang Zhang Lu Shou Jiangning Zeng Quanzhen Chen 《Acta Oceanologica Sinica》 2025年第1期113-126,I0001-I0011,共25页
Macrobenthic organisms are commonly employed as biomonitors for environmental risk assessment.In this study,we aimed to investigate the spatial and temporal patterns of the macrobenthic community,which is influenced b... Macrobenthic organisms are commonly employed as biomonitors for environmental risk assessment.In this study,we aimed to investigate the spatial and temporal patterns of the macrobenthic community,which is influenced by environmental factors of sediments and bottom water layer.We sampled a total of 12,11,10,and 11 stations in the Shengsi Archipelago during June 2010,August 2010,November 2020,and April 2021 respectively.A total of 124 species of macrobenthos were identified,with polychaetes being the dominant group.The abundance,biomass,and diversity indices exhibited no significant temporal differences.Similarly,biodiversity did not exhibit a clear spatial gradient,likely due to the small study area and the absence of significant differences in key factors such as depth.However,the stations with the lowest biodiversity values consistently appeared in the southwest region,possibly due to the impact of human activities.Significant differences in the macrobenthic community were observed between all months except between June and August,and mollusk Endopleura lubrica and polychaete Sigambra hanaokai were important contributors to these differences according to the results of the Similarity Percentages analysis.Suspended particulate matter(SPM)was identified as the primary driving factors of macrobenthic variability.In summary,the community structure underwent temporal changes influenced by complex current patterns,while biodiversity remained relatively stable.This study contributes to our understanding of the key environmental factors affecting macrobenthic communities and biodiversity.It also provides valuable data support for the long-term monitoring of macrobenthos and the environment in the Shengsi Archipelago. 展开更多
关键词 macrobenthic community Shengsi Archipelago distribution pattern BIODIVERSITY environmental factors
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Distribution pattern of rare plants along riparian zone in Shennongjia Area 被引量:4
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作者 江明喜 邓红兵 蔡庆华 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期25-27,83,共3页
Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian z... Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian zone in basic study and practical management. In this study, 42 sampling belts (10 m?00 m) parallel to the bank of Xiangxi River at different elevations in Shennongjia Area were selected to investigate the riparian vegetation and rare plants. 14 species of rare plants were found distributing in riparian zone, accounting for 42.4% of the total rare plant species in Shennongjia Area. The main distribution range of the 14 rare plant species was the evergreen and deciduous mixed broadleaved forest at elevation of 1200-1800 m, where, species diversity of plant community was the maximum at the moderate elevation. The analysis of TWINSPAN divided the 14 rare species into 3 groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation species group. The analysis of DCA ordination showed similar results to that of TWINSPAN. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out that the important function of riparian zone on rare plant species protection. 展开更多
关键词 Xiangxi River Rare plant Riparian zone Distribution pattern BIODIVERSITY
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Distribution Patterns of Ground Moss Species and Its Relationships with Environmental Factors in Changbai Mountain, Northeast China 被引量:5
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作者 郭水良 曹同 《Acta Botanica Sinica》 CSCD 2001年第6期631-643,共13页
The relationships of 42 species of ground moss with six environmental factors in 41 sites on Changbai Mountain Biosphere Reserve were analyzed. Four site groups and four groups of ground moss ecological species were i... The relationships of 42 species of ground moss with six environmental factors in 41 sites on Changbai Mountain Biosphere Reserve were analyzed. Four site groups and four groups of ground moss ecological species were identified using the method of Two-way Indicator Species Analysis (TWINSPAN). The results of Detrended Canonical. Correspondence Analysis (DCCA) showed that altitude, soil sand content, soil acidity, forest canopy coverage and soil water content are the five major environmental factors influencing the distributional patterns of the moss species. The four groups of ecological species, which correspond well with the four site groups, are projected on the species-environment biplot of DCCA. Group 1 dominated in the bogs of Larix olgensis forest, group 2 in the alpine tundra, group 3 in the dense conifer forest, and group 4 mainly in the Betula ermanii community and the Betula ermanii-Larix olgensis forest in sub-alpine respectively. 展开更多
关键词 MOSSES Changbai Mountain distribution pattern detrended canonical correspondence analysis
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Study on Spatial Distribution Pattern of Thrip (Odentot hrips lati) on Alfalfa (Medicago sativa) 被引量:1
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作者 赵丽丽 王普昶 +1 位作者 刘玉良 陈彦希 《Agricultural Science & Technology》 CAS 2011年第7期990-993,共4页
[Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip(Odentot hrips lati) on alfalfa(Medicago sativa).[Method] Within alfalfa plantation areas,experimental plots wit... [Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip(Odentot hrips lati) on alfalfa(Medicago sativa).[Method] Within alfalfa plantation areas,experimental plots with the sizes of 10×10,10×20,10×30,20×30,20×40,20×80,30×30,30×40,30×50,40×40,40×50,40×80 and 50×50 m2 respectively were set up in the randomly selected sampling sites of 1 m ×2 m in size.During bud-emerging period and florescence period of alfalfa in the experimental plots,the number of thrips was counted and their distribution pattern was measured using XU Ru-mei's method.[Result] During bud-emerging period of alfalfa,the spatial distribution of thrips assumed an elliptic shape sized of 40×30-40×40 cm2 at horizontal level and that presented an ascending-falling trend of tress density down from the top at vertical level.During the florescence period of alfalfa,it showed a homogeneous distribution or randomly distributed pattern at horizontal level and a falling trend of tress density from the top to the apex to the root at vertical level.[Conclusion] Our results provide theoretical basis for field selection of insect-resistant alfalfa varieties. 展开更多
关键词 THRIPS Different degree Distribution pattern ALFALFA
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Spatial Distribution Pattern and Application of Fourth-Generation Mature Larvae of Cotton Bollworm(Helicoverpa armigera Hübner) in Corn Field
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作者 李贺年 齐巧丽 +1 位作者 李德新 姚克荣 《Plant Diseases and Pests》 CAS 2011年第2期36-38,共3页
[ Objective] The paper was to study the spatial distribution pattern of fourth-generation mature larvae of cotton bellworm in corn field. [ Method] The plots with different occurrence densities of fourth-generation co... [ Objective] The paper was to study the spatial distribution pattern of fourth-generation mature larvae of cotton bellworm in corn field. [ Method] The plots with different occurrence densities of fourth-generation cotton bollworm were investigated from August to September in 2009. Six groups of sampling data were obtained, and seven indicators including aggregation index method, Iwao method and Taylor method, etc. were used to determine its spatial distribution pattern. [ Result ] Aggregation index test showed that in all plots, Moore I 〈 0, Lloyed m*/m 〈 1, Kuno Ca 〈 0, diffusion coefficient C 〈 1, diffusion index 16 〈 1, negative binomial distribution K 〈 0, indicating that mature larvae of cotton bollworm showed uniform distribution in summer corn. Iwae regression equation of fourth-genera- tion mature larvae of cotton boUworm in summer corn was m * = 0. 090 6 + 0. 766 9 m, r = 0. 986 3, indicating that the basic components of cotton bollworm distribu- ted was single individual, and mature larvae of cotton bollworm in summer corn showed uniform distribution. The optimal sampling number of fourth-generation ma- ture larvae of cotton bollworm in corn under different population densities could be calculated using formula N1 = ( 1. 090 6/m -0. 233 1 )/D2. [ Conclusion] The result provided basis for accurate evaluation of population quantities and variation law of cotton boUworm, as well as prediction and control of the pest. 展开更多
关键词 MAIZE Cotton bollworm Spatial distribution pattern Sampling technique
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Preliminary Study on Spatial Distribution Pattern of Endoclyta signifer Walker Larva
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作者 曹书阁 庞正轰 +2 位作者 杨秀好 于永辉 丘润清 《Plant Diseases and Pests》 CAS 2011年第2期28-31,72,共5页
[ Objective ] The paper was to study the spatial distribution of Endoclyta signifer Walker Larva. [ Method] The larvae distribution in eucalyptus planta- tion in Beiliu and Luchuan counties of Guangxi province were in... [ Objective ] The paper was to study the spatial distribution of Endoclyta signifer Walker Larva. [ Method] The larvae distribution in eucalyptus planta- tion in Beiliu and Luchuan counties of Guangxi province were investigated. Ten standard plots were set, and the spatial distribution pattern of E. signifer larva was confirmed using six different aggregation indexes and regression model analysis method. [ Result] The larvae mainly distributed in the base of tnmk lower than 1 m, and its spatial distribution pattern was mainly aggregated distribution, which was caused by the enviromnental factors. The optimum sampling formula of E. signifer larva under different population densities was n = t2 ( 1.1/m + 0. 674 4)/D2, and limited sequential sampling decision model was T'0(n), T'0(n) = n + 1. 332√n( m0 = 1 ). [ Conclusion] The result provided scientific basis for sampling and forecasting of E. signifier. 展开更多
关键词 Endoclyta signifer Walker Spatial distribution pattern Aggregation indexes Regression model
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Space-time Distribution Pattern of Monochamus alternatus in Wanding City
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作者 熊忠平 涂玉 司徒英贤 《Plant Diseases and Pests》 CAS 2010年第2期35-37,共3页
[Objective] The purpose was to study space-time distribution pattern of Monochamus alternatus in Wanding City. [Method] Based on data about insect situation supervision on M. alternatus in Wanding City, using related ... [Objective] The purpose was to study space-time distribution pattern of Monochamus alternatus in Wanding City. [Method] Based on data about insect situation supervision on M. alternatus in Wanding City, using related mathematical statistics methods including linear regression analysis and spatial distribution pattern of insect population, the relationship between emergence period, emergence quantity and temperature of M. alternatus adult, spatial distribution pattern of adults and their life history were studied. [Result] M. alternatus occurred one generation per year in Wanding city, June was the maximum period of adults, which was also the key trapping period. Spatial distribution of M. alternatus was accumulative. [Conclusion] This study provided theoretical basis for further control on M. alternatus for forestry bureau of Wanding City. 展开更多
关键词 Wanding Monochamus alternatus Life history Spatial distribution pattern
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Spatial Distribution Pattern of Overwintering Larvae of Dendrlimus punctatus
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作者 刘有莲 《Plant Diseases and Pests》 CAS 2010年第4期32-35,共4页
Based on the data of mean population density of overwintering larvae of Dendrolimus punctatus in Shatang forest farm in Guangxi Province, the spatial pattern of overwintering larva of D. punctatus were analyzed by the... Based on the data of mean population density of overwintering larvae of Dendrolimus punctatus in Shatang forest farm in Guangxi Province, the spatial pattern of overwintering larva of D. punctatus were analyzed by the distribution index and regression model method. The results showed that the spatial pattern of overwintering larvae of D. punctatus assumed the aggregation pattern, the basic component of distribution was individual group. The optimal sampling number of forest survey and the sequential sampling analysis were presented, and the upper and low bound index for controlling D. punctatus were put forward to provide certain theoretical basis for integrated pest management. 展开更多
关键词 Dendrolimus punctatus Walker. Spatial distribution pattern Sequential sampling Guangxi Shatang forest farm
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Developmental Mechanism and Distribution Pattern of Stomatal Clusters in Begonia peltatifolia 被引量:7
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作者 唐敏 胡玉熹 +1 位作者 林金星 靳晓白 《Acta Botanica Sinica》 CSCD 2002年第4期384-390,共7页
The function of stomata in plants is controlling gas exchange and modulating water balance. The distribution pattern of stomata in most vascular plants follows a certain regulation with at least one normal epidermal c... The function of stomata in plants is controlling gas exchange and modulating water balance. The distribution pattern of stomata in most vascular plants follows a certain regulation with at least one normal epidermal cell between two stomata. However, some plants restricted in several genera of vascular plants have stomatal clusters in which more than one stoma is adjacently arranged with no epidermal cells among them. The developmental process of stomatal clusters in plants, especially in non-mutant (wild type) vascular plants, has rarely been documented, and very few studies concerning the distribution pattern of stomatal clusters on leaf epidermis have been carried out. We reported the developmental mechanism and distribution pattern of stomatal clusters in Begonia peltatifolia Li native to China. The results indicated that the clustered arrangement of meristemoids at the juvenile stage of the leaf development contributed greatly to the pattern of stomatal clusters. Additionally, satellite meristemoids derived from subsidiary cells around the mature stomata also had an impact on the development as well as the pattern of stomatal clusters. Regarding stomatal cluster and singly occurring stoma both as a stomatal unit, we found that the stomatal unit density (i.e., number of stomatal unit per area) increased gradually from the middle part to the edge and the apex of the leaf, while stomatal unit size (i.e., number of stomata per stomatal unit) decreased. The possible reason of this pattern was discussed. 展开更多
关键词 Begonia peltatifolia DEVELOPMENT distribution pattern stomatal cluster
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On Spatial Distribution Pattern of Broccoli Clubroot Disease and and the Sampling Technique 被引量:1
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作者 钟列权 王会福 余山红 《Agricultural Science & Technology》 CAS 2015年第12期2715-2719,共5页
[Objective] To further improve the prediction and forecast and continuous control ability of broccoli clubroot disease. [Methods] The spatial distribution pattern of diseased or infected plants was analyzed using the ... [Objective] To further improve the prediction and forecast and continuous control ability of broccoli clubroot disease. [Methods] The spatial distribution pattern of diseased or infected plants was analyzed using the least square method, fre- quency distribution, aggregation index, m*-m regression analysis and Taylor's pow- er law model. [Result] The field distribution of broccoli plants with clubroot disease tended to be aggregated distribution, m'-m regression analysis showed that the el- ementary composition of the spatial distribution of diseased or infected plants was individual colony, the individuals attracted each other; the disease had obvious dis- ease focus in the field, and the individual colony showed uniform distribution pattern in the field. Taylor's power law showed that the spatial pattern of individual dis- eased or infected plant with clubroot disease tended to be uniform distribution with the increase of the density. On the basis of this, Iwao optimal theoretical sampling model and sequential sampling model were established, namely N =273.954 1/m- 59.698 5, To (N)=0.368 4N±1.926 8√N, respectively, it meant that when surveying N plants, if the accumulative incidence rate exceeded upper bound, the field can be set as control object; if the accumulative incidence rate didn't reach lower bound, it can be set as uncontrol field; if the accumulative incidence rate was between upper bound and lower bound, it should be surveyed continuously until the maximum sample size (mo=0.368 4) appeared, that was, the disease incidence was 15%, so the sampling number should be 684 plants. [Conclusion] The research results had very important instructive meaning for disease control. 展开更多
关键词 Broccoli clubfoot disease Spatial distribution pattern The optimal theo- retical sampling model Sequential sampling model Sampling number
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