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“落红”与“幽月”——浅议宋词中的言“愁”意象
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作者 陈宁宁 《山东农业大学学报(社会科学版)》 2004年第1期71-73,78,共4页
"愁"作为人们一种普遍的情绪体验,在宋词中经常得以表现。在具体创作中,词人往往借助某些具有特定文化内涵和情感指向的意象进行传达。本文着重指出"落红"与"幽月"二意象来阐释词人的言"愁"情怀。
关键词 宋词 “愁” 意象 “落红” “幽月”
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“落花”、“落英”与“落红”
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《现代语文(高中版)》 2004年第7期19-19,共1页
本期我们选用了语文报刊网(www.zgywsb.net)之语文论坛上“高中师生茶座”里绿水清荷老师首先提出的“古代诗歌中‘落英’与‘落花’如何区别”的问题。在这里,几位老师的讨论不仅让我们学到了知识,更向我们展示了一种宝贵的治学态度。
关键词 “落花” “落英” “落红” 高中 语文 古代诗歌 背景知识
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“落英”“落红”“落花”之异同
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作者 霍文英 《中学语文教学参考(中旬刊)》 北大核心 2014年第8期73-74,共2页
人教版七年级下册语文教材中的第238页是古诗《江南逢李龟年》,其中一句是“正是江南好风景,落花时节又逢君”。根据课前的导读,“落花”可理解为凋零之花。人教版八年级上册语文教材中的第163页是文言文《桃花源记》,其中有一句“... 人教版七年级下册语文教材中的第238页是古诗《江南逢李龟年》,其中一句是“正是江南好风景,落花时节又逢君”。根据课前的导读,“落花”可理解为凋零之花。人教版八年级上册语文教材中的第163页是文言文《桃花源记》,其中有一句“忽逢桃花林,夹岸数百步,中无杂树,芳草鲜美,落英缤纷”。课文下面对“落英”注释是“落花”,一说初开的花。人教版八年级下册语文教材中的第211页是古诗《己亥杂诗》,其中一句是“落红不是无情物,化作春泥更护花”,课文下面对“落红”的注释是“落花”。 展开更多
关键词 “落花” “落红” “落英” 《江南逢李龟年》 《桃花源记》 八年级下册 异同 语文教材
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Non-cooperative Space Target Estimation Algorithm Without Prior Information Dependence Based on Temporal Line of Sight Constraint
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作者 XIAO Hui ZHU Chongrui +3 位作者 LIU Xinqi YU Yifan SHENG Qinghong YANG Rui 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期526-540,共15页
Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a p... Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a parameter estimation model of the boost phase based on trajectory plane parametric cutting.The use of the plane passing through the geo-center and the cutting sequence line of sight(LOS)generates the trajectory-cutting plane.With the coefficient of the trajectory cutting plane directly used as the parameter to be estimated,a motion parameter estimation model in space non-cooperative targets is established,and the Gauss-Newton iteration method is used to solve the flight parameters.The experimental results show that the estimation algorithm proposed in this paper weakly relies on prior information and has higher estimation accuracy,providing a practical new idea and method for the parameter estimation of space non-cooperative targets under single-satellite warning. 展开更多
关键词 motion parameter estimation estimation of impact point infrared early warning boost phase modeling trajectory database construction
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Analysis of organic acids in selected forest litters of Northeast China 被引量:7
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作者 宋金凤 崔晓阳 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期285-289,共5页
Larch (Larix olgensis), Manchurian ash (Fraxinus mandshurica), Korean pine (Pinus koraiensis) and White birch (Betula platyphylla) are the major planting species in northeast China. The samples of forest litters were ... Larch (Larix olgensis), Manchurian ash (Fraxinus mandshurica), Korean pine (Pinus koraiensis) and White birch (Betula platyphylla) are the major planting species in northeast China. The samples of forest litters were collected from the stands of the above 4 species in Laoyeling and Jianlagou experiment stations of Maorshan Exp. Forest Farm (45?2-45?0N, 127?0-127?8E), Northeast Forestry University, in early October 2002. Quantitative analysis and qualitative analysis were carried out on the organic acids existing in freshly fallen litters (L layer) and hemi-decomposed litters (F layer) of the four forest species by using Gas Chromatogram system. A wide variety of organic acids were identified, including oxalic, malonic, fumaric, succinic, maleic, malic, citric, C16:0, C18:0, C18:1, C18:2, C18:3 and C20:0 acids. In respect of L litters of all samples, the oxalic acid content (over 30 mg/g) was the highest of the seven low-molecular-weight organic acids identified, while the content of oleic or linoleic (above 40 mg/g) was found to be highest among the six high aliphatic acids identified. As to F litters, oxalic acid content was also the highest, followed by linoleic and oleic. For the same tree species or the same forest, the kinds and contents of organic acids in L litters were more abundant than that in F litters. 展开更多
关键词 Forest litter Organic acid Capillary gas chromatography
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A Comparison of Macrofauna Communities in Different Mangrove Assemblages 被引量:9
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作者 唐以杰 余世孝 吴延勇 《Zoological Research》 CAS CSCD 北大核心 2007年第3期255-264,共10页
The characteristics of macrofauna communities in three mangrove assemblages [Avicennia marina+Acgiceras corniculatum (MC)community, A.corniculatum (C) community and Bruguiera gymnorrhiza+A.corniculatum (GC) co... The characteristics of macrofauna communities in three mangrove assemblages [Avicennia marina+Acgiceras corniculatum (MC)community, A.corniculatum (C) community and Bruguiera gymnorrhiza+A.corniculatum (GC) community] were studied in Zhanjiang Mangrove Nature Reserves during 2005 and 2006. Of the three mangrove assemblages, the macrofauna species number, density, biomass, Richness index and Shannon-Wiener index were the highest, and the Simpson dominance index was medial at MC community. However the Pielou Evenness index of MC community was slightly lower than that at C community. At C community, the number of macrofauna species obviously reduced, especially infaunal, caving and adhering life forms, and the biomass and density were the lowest. Because of the even distribution of individuals of different species, the Simpson dominance index was the lowest and the evenness index was the highest. Although the Richness index at C community was slightly lower than that at MC community, the Shannon-Wiener index was near to that at MC community. At GC community, the number of macrofauna species, especially infaunal and caving life forms, continued to decrease comparing C community, but the biomass and density increased slightly. As the distribution of individuals of different species was uneven, the Simpson dominance index was the highest and the Pielou Evenness index was the lowest. Furthermore, the Richness index dropped to the lowest. The Shannon-Wiener index also dropped accordingly to the lowest. The dominant life forms of MC were infaunal and caving, while those of C and GC community were both caving. The ratio of the GS/GSB of macrofauna communities in the three mangrove assemblages were 0.48, 0.63 and 0.80, respectively. The community structures at the same mangrove assemblages were all quite similar, with those at GC community being most similar. However, there were obvious differences among the community structures at the three different mangrove assemblages. These results implied that the different mangrove assemblages had different affects on the macrofauna communities and shed light on the macrofauna adaptation capability to specific habitats. 展开更多
关键词 Mangrove community MACROFAUNA Community structure
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Relationships between bird communities and vegetation structure in Honghuaerji, northern Inner Mongolia 被引量:2
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作者 王文 丸山直树 +2 位作者 刘伯文 森本英人 高中信 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期294-298,337,共5页
The survey on bird communities was conducted by the belt-style method in six different sample plots in the Honghua抏rji Forests area in the northern Inner Mongolia in June 2001 and totally 28 bird species were recorde... The survey on bird communities was conducted by the belt-style method in six different sample plots in the Honghua抏rji Forests area in the northern Inner Mongolia in June 2001 and totally 28 bird species were recorded. Vegetation investigation was carried out in five 10 m×10 m quadrats at each plot. The asymptotic regression function formulae were adopted to identify the relationships between the vegetation coverage and the numbers of bird species and individuals. The analytical results showed that the changes of species number and density of bird as well as the formation of bird communities follow the changes of forest type and the total foliage. Both the number of bird species and their density decreased with the de-crease of total foliage. The similarity of bird community was very low at the breeding time. In the same classification of cluster, no similarity was higher than 0.65, which indicated that the composition of species had a great difference between all the bird communities. The bird breeding density was closely related to forest growth stage. From the bare grassland ecosystem to cli-max ecosystem, the density of bird species showed a gradually increasing trend. 展开更多
关键词 Bird community Vegetation structure Honghua抏rji Northern Inner Mongolia
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也谈幸福
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作者 刘锦琼 《江苏教育》 2018年第86期80-80,共1页
人生百年内,疾速如过隙.转眼间,我与三尺讲台相伴也已17年.对于师者,人们常常以“落红”“蜡炬”来比喻,但这种比喻,我总觉得过于凄婉.教师这个职业固然带有奉献性的色彩,但是教师的一生也绝非“落红春泥”“蜡炬成灰”的一生.教书育人... 人生百年内,疾速如过隙.转眼间,我与三尺讲台相伴也已17年.对于师者,人们常常以“落红”“蜡炬”来比喻,但这种比喻,我总觉得过于凄婉.教师这个职业固然带有奉献性的色彩,但是教师的一生也绝非“落红春泥”“蜡炬成灰”的一生.教书育人,虽不至于轰轰烈烈、众人瞩目,但是“桃李不言,下自成蹊”,一样也有它的价值和意义.而对于教师来说,面对这份日复一日年复一年的工作,幸福感又何在? 展开更多
关键词 幸福感 “落红” 教书育人 奉献性 教师 比喻 师者 讲台
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宣扬这种伦理观
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作者 刘飞锋 《中国地市报人》 2007年第8期64-64,共1页
广西某都市报2007年5月29日刊发了《短暂初恋为何荒唐收场?》一文的后续报道。该文报道了一个叫唐某的男子因第一次与女友发生关系,发现女友没有“落红”,认为她不是处女,就不愿继续跟其交往下去。随后,该记者便追踪采写了这篇讨... 广西某都市报2007年5月29日刊发了《短暂初恋为何荒唐收场?》一文的后续报道。该文报道了一个叫唐某的男子因第一次与女友发生关系,发现女友没有“落红”,认为她不是处女,就不愿继续跟其交往下去。随后,该记者便追踪采写了这篇讨论“处女观”的后续报道:《是否处女,爱恨有几分》。“不要钱,不要貌,我要老婆是处女”,只是其中一节的小标题,报道了一位大学本科毕业的刘先生的“处女观”。不能不让人感到气愤了。 展开更多
关键词 伦理观 后续报道 “落红” 大学本科 都市报 小标题 荒唐 女友
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Effects of fire disturbance on the forest structure and succession in the natural broad-leaved/Korean pine forest 被引量:7
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作者 刘丽娟 葛建平 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期269-274,共6页
Investigations on charcoal in the soil, fire-scarred trees, stand composition, forest structure as well as regeneration status were carried out in the natural broad-leaved/Korean pine (Pinus koraiensis) forest after f... Investigations on charcoal in the soil, fire-scarred trees, stand composition, forest structure as well as regeneration status were carried out in the natural broad-leaved/Korean pine (Pinus koraiensis) forest after fire disturbance at Liangshui Nature Reserve on the mid-north of Xiaoxingan Mountains from 1990 to 1992, and the ecological effects of fire disturbance on the formation and succession of this kind of forest were analyzed according to the survey results. The average depth of charcoal in the soil was related to the timing of the fire. According to the characteristic of fire-scarred trees, the dynamic map of the fire behavior was drawn onto the topographic map. It showed that the dimension and extent of the fire disturbance was closely related with site conditions. Fire disturbance only led to a significant difference in stand composition and diameter class structure for the stands at different locations, rather than completely destroying the forest. After fire disturbance, the horizontal community structure was a mosaic of different patches, which were made up of different deciduous species or different sizes of Korean pines, and the succession trend of each patch was also different. In the sites with the heavy fire disturbance, the intolerant hardwood species were dominant, and there were a large number of regenerative Korean pine saplings under the canopy. In the moderate -disturbed sites, the tolerant hardwood species were dominant, and a small number of large size Korean pines still survived. In the light-disturbed sites, large size Korean pines were dominant. 展开更多
关键词 Pinus koraiensis Natural forest Fire disturbance SUCCESSION
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Plant community composition and interspecific relationships among dominant species on a post-seismic landslide in Hongchun Gully, China 被引量:6
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作者 HUANG You-you HAN Han +1 位作者 TANG Chuan LIU Shou-jiang 《Journal of Mountain Science》 SCIE CSCD 2017年第10期1985-1994,共10页
The 5.12 Earthquake in 2008 and 8.14 Debris Flow in 2010 resulted in large-scale landslides that disturbed vast areas of vegetation in the Hongchun Gully, Wenchuan County, China. To define the specific characteristics... The 5.12 Earthquake in 2008 and 8.14 Debris Flow in 2010 resulted in large-scale landslides that disturbed vast areas of vegetation in the Hongchun Gully, Wenchuan County, China. To define the specific characteristics of vegetation restoration during natural recovery after catastrophic events,vegetation species composition and interspecific associations were investigated on this typical landslide. Field survey data selected from a total of 51 sample plots belonged to seven belt transects and were analysed by Schluter's variance ratio, pearson's chi-squared test, Spearman's correlation coefficients and ecological species groups. Plant communities on the landslide consisted of 78 species, 65 genera and52 families. Of the total of 78 species, 25 are identified as dominant species, among which Camptotheca acuminate, Toxicodendron vernicifluum, Coriaria nepalensis, Robinia pseudoacacia, Buddleja alternifolia, Anemone vitifolia and Nephrolepis auriculata play a constructive role during the natural afforestation. Moreover, according to environmental and ecological factors, these 25 dominant species could be divided into four ecological species groups.This study found that even though the landslide had frequently suffered from interference due to heavy rain, the vegetation succession processes are ongoing,and it is now at a shrub–herb community succession stage, which indicates that vegetation can naturally recover in the denuded sites. This study provides a useful insight into the ecological interactions and interdependence between plant species during the natural recovery of vegetation and provides valuable information on vegetation recovery modelling in the landslide area. 展开更多
关键词 Ecological rehabilitation Plant communities Vegetation recovery Geological hazard Hongchun Gully
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Geochip-based analysis of microbial functional genes diversity in rutile bio-desilication reactor
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作者 宋翔宇 邱冠周 +3 位作者 王海东 谢建平 徐靖 王娟 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2922-2928,共7页
Biological desilication process is an effective way to remove silicate from rutile so that high purity rutile could be obtained. However, little is known about the molecular mechanism of this process. In this work, a ... Biological desilication process is an effective way to remove silicate from rutile so that high purity rutile could be obtained. However, little is known about the molecular mechanism of this process. In this work, a newly developed rutile bio-desilication reactor was applied to enrich rutile from rough rutile concentrate obtained from Nanzhao rutile mine and a comprehensive high through-put functional gene array(Geo Chip 4.0) was used to analyze the functional gene diversity, structure and metabolic potential of microbial communities in the biological desilication reactor. The results show that TiO2 grade of the rutile concentrate could increase from 78.21% to above 90% and the recovery rate could reach to 96% or more in 8-12 d. The results also show that almost all the key functional genes involved in the geochemical cycling process, totally 4324 and 4983 functional microorganism genes, are detected in the liquid and ore surface, respectively. There are totally 712 and 831 functional genes involved in nitrogen cycling for liquid and ore surface samples, respectively. The relative abundance of functional genes involved in the phosphorus and sulfur cycling is higher in the ore surface than liquid. These results indicate that nitrogen, phosphorus and sulfur cycling are also present in the desiliconization process of rutile. Acetogenesis genes are detected in the liquid and ore surface, which indicates that the desiliconizing process mainly depends on the function of acetic acid and other organic acids. Four silicon transporting genes are also detected in the sample, which proves that the bacteria have the potential to transfer silicon in the molecule level. It is shown that bio-desilication is an effective and environmental-friendly way for enrichment of rough rutile concentrate and presents an overview of functional diversity and structure of desilication microbial communities, which also provides insights into our understanding of metabolic potential in biological desilication reactor ecosystems. 展开更多
关键词 RUTILE functional gene diversity silicate bacteria BIOLEACHING
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Carbon Stock of Larch Plantations and Its Comparison with an Old-growth Forest in Northeast China 被引量:8
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作者 QI Guang CHEN Hua +7 位作者 ZHOU Li WANG Xinchuang ZHOU Wangming QI Lin YANG Yuhua YANG Fengling WANG Qingli DAI Limin 《Chinese Geographical Science》 SCIE CSCD 2016年第1期10-21,共12页
The overall goal of this study was to understand carbon(C) stock dynamics in four different-aged Japanese larch(Larix kaempferi) plantations in Northeast China that were established after clear-cutting old-growth Kore... The overall goal of this study was to understand carbon(C) stock dynamics in four different-aged Japanese larch(Larix kaempferi) plantations in Northeast China that were established after clear-cutting old-growth Korean pine deciduous forests. Four Japanese larch plantations which were at 10, 15, 21, and 35 years old and an old-growth Korean pine deciduous forest which was 300 years old in Northeast China were selected and sampled. We compared the C pools of biomass(tree, shrub and herb), litterfall(LF), and soil organic carbon(SOC) among them. The biomass C stock of larch plantation at 10, 15, 21, and 35 years old was 26.8, 37.9, 63.6, and 83.2 Mg/ha, respectively, while the biomass C stock of the old-growth Korean pine deciduous forest was 175.1 Mg/ha. The SOC stock of these larch plantations was 172.1, 169.7, 140.3, and 136.2 Mg/ha respectively, and SOC stock of 170.4 Mg/ha in the control of old-growth forest. The biomass C stock increased with stand age of larch plantations, whereas SOC stock decreased with age, and C stock of LF did not change significantly(P > 0.05). The increase of biomass C offset the decline of SOC stock with age, making total carbon stock(TCS) of larch plantations stable from stand ages of 10–35 years. The TCS in larch plantations was much smaller than that in the old-growth forest, suggesting that the conversion of old-growth forests to young larch plantations releases substantial C into the atmosphere. 展开更多
关键词 larch plantation old-growth forest biomass carbon soil organic carbon total carbon stocks
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Volatile Constituents of Juniperus communis L., Taxus canadensis Marshall. and Tsuga canadensis (L.) Carr. from Canada
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作者 OEmer Kilic Alpaslan Kocak 《Journal of Agricultural Science and Technology(B)》 2014年第2期135-140,共6页
The essential oil composition leaves of Juniperus communis L., Taxus canadensis Marshall. and Tsuga canadensis (L.) Carr. from Canada were investigated by head space solid phase microextraction (HS-SPME) and gas c... The essential oil composition leaves of Juniperus communis L., Taxus canadensis Marshall. and Tsuga canadensis (L.) Carr. from Canada were investigated by head space solid phase microextraction (HS-SPME) and gas chromatography/mass spectrometry (GC-MS). Thirty-three, thirty and thirty-one components were identified representing 95.78%, 93.89%, 96.14% of the oil, respectively. Limonene (26.12%), benzene (15.62%), 13-mrycene (9.08%) and β-pinene (7.30%) were found to be the main constituents of J. communis; 1-propanone (36.38%), morpholine (10.95%), methylamine (9.10%) and methanone (8.14%) were detected main components of Taxus canadensis; bornylacetate (26.84%), α-pinene (23.74%), camphene (11.93%) and limonene (6.02%) were determined as major constituents of Tsuga canadensis. The chemical distributions of the essential oil compounds in the genus pattern were discussed in means of chemotaxonomy and natural products. 展开更多
关键词 JUNIPERUS TAXUS TSUGA essential oil CANADA HS-SPME GC-MS.
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Vegetation of Mangroves: Spatial and Temporal Pattern of its Dominant Populations in Futian National Nature Reserve
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作者 李振基 郑文教 +2 位作者 杨志伟 林益明 林鹏 《Marine Science Bulletin》 CAS 2003年第2期40-53,共14页
The community characteristics of mangroves in the Futian Nature Reserve, Shenzhen, China are given based on surveying of 33 quadrats in 4 transects which stretch from the higher tidal zone to the lower tidal zone. The... The community characteristics of mangroves in the Futian Nature Reserve, Shenzhen, China are given based on surveying of 33 quadrats in 4 transects which stretch from the higher tidal zone to the lower tidal zone. The results show that there are 6 community types in this area: Kandelia candel association, Avicennia marina association, Aegiceras corniculatum association, Kandelia candel + Aegiceras corniculatum association, Aegiceras corniculatum + Kandelia candel association and Acanthus ilicifolius association. Kandelia candel, Aegiceras corniculatum and Avicennia marina dominate the typical quadrats. Kandelia candel can be seen at almost all quadrats, Aegiceras corniculatum distributes mostly toward the estuary and the higher tidal zone, Avicennia marina distributes mostly toward the bay and the lower tidal zone, Bruguiera gymnorrhiza occasionally occurs toward the Estuary with one or several individuals, Acanthus ilicifolius was common toward the higher tidal zone, as an accompanying species, Derris trifoliata was common in many mature quadrats. Totally, 6 species of mangrove plants and 3 species of semi-mangrove plants appear in this research area. From the higher tidal zone to the lower tidal zone, the average diameter and basal area of mangrove trees increase gradually. According to the results, the Avicennia marina dominates in average diameter and basal area, and the Aegiceras corniculatum trees are on the contrary. From the transect 1 to the transect 4, the importance value of Avicennia marina, Bruguiera gymnorrhiza and Kandelia candel decreases, and Aegiceras corniculatum increases. In this area, the Kandelia candel population and Aegiceras corniculatum population are developing populations with many seedlings and saplings, but the Avicennia marina population is in a mature stage with few seedlings and not so many total individuals. According to this research, we suppose that Aegiceras corniculatum should be developed toward the estuary and the Avicennia marina association should be protected. 展开更多
关键词 vegetation analysis kandelia candel avicennia marina aegicerascorniculatum COMMUNITY population structure SHENZHEN
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随想
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作者 陈义民 《江西教育(管理版)(A)》 2017年第10期44-45,共2页
1.大自然有真正的死亡么?没有。生死相依,循环不已,这种死,不能叫真正的死亡。庄子比喻得好:谷不存在了,分成米和糠,这“不存在”,不能算真的死。龚定庵的“落红不是无情物,『艺作春泥更护花”,这“落红”,当然也不是真的死。
关键词 随想 “落红” 大自然 死亡
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Species Abundance Distribution Patterns of a Toona ciliata Community in Xingdoushan Nature Reserve 被引量:4
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作者 WANG Yang ZHU Shengjie +3 位作者 LI Jie HE Xiuling JIANG Xiongbo ZHANG Min 《Journal of Resources and Ecology》 CSCD 2019年第5期494-503,共10页
With the goal of model fitting species abundance distribution patterns of the tree,shrub and herb layers of the natural Toona ciliata community in Xingdoushan Nature Reserve,Enshi Autonomous Prefecture,Hubei Province,... With the goal of model fitting species abundance distribution patterns of the tree,shrub and herb layers of the natural Toona ciliata community in Xingdoushan Nature Reserve,Enshi Autonomous Prefecture,Hubei Province,we used the data collected from the field survey and employed different ecological niche models.The models tested were the broken stick model(BSM),the overlapping niche model(ONM)and the niche preemption model(NPM),as well as three statistic models,the log-series distribution model(LSD),the log-normal distribution model(LND)and the Weibull distribution model(WDM).To determine the fitted model most suitable to each layer,the fitting effects were judged by criteria of the lowest value of Akaike Information Criterion(AIC),Chi-square and the K-S values with no significant difference(P>0.05)between the theoretical predictions and observed species abundance distribution values.The result showed:(1)The fitting suitability and goodness of fit of the tree,shrub and herb layers by using the three ecological niche models were ranked as:NPM>BSM>ONM.Of the three statistical models,by accepting the fitting results of the three layers,WDM was the best fitting model,followed by LND.By rejecting the fitting tests of the herb layer,LSD had the worst fitting effect.The goodness of the statistical models was ranked as:WDM>LND>LSD.In general,the statistical models had better fitting results than the ecological models.(2)T.ciliata was the dominant species of the tree layer.The species richness and diversity of the herb layer were much higher than those of either the tree layer or the shrub layer.The species richness and diversity of the shrub layer were slightly higher than those of the tree layer.The community evenness accorded to the following order:herb>shrub>tree.Considering the fitting results of the different layers,different ecological niche models or statistical models with optimal goodness of fit and ecological significance can be given priority to in studying the species abundance distribution patterns of T.ciliata communities. 展开更多
关键词 Toona ciliata community tree-shrub-herb layer niche model statistical model species abundance distribution pattern fitting model
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Characteristics and Carbon Storage of a Typical Mangrove Island Ecosystem in Beibu Gulf,South China Sea 被引量:3
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作者 WU Bin ZHANG Wenzhu +3 位作者 TIAN Yichao LIANG Mingzhong XU Jun GU Guanhai 《Journal of Resources and Ecology》 CSCD 2022年第3期458-465,共8页
By studying the structural characteristics and carbon storage of the mangrove island ecosystem in the Beibu Gulf,this study provides a scientific basis for mangrove ecological compensation in the coastal areas of Guan... By studying the structural characteristics and carbon storage of the mangrove island ecosystem in the Beibu Gulf,this study provides a scientific basis for mangrove ecological compensation in the coastal areas of Guangxi,South China Sea.On the basis of the unmanned aerial vehicle remote sensing images and a sample plot survey,the object-oriented multi-scale segmentation algorithm is used to extract the mangrove community type information,and one-way analysis of variance is conducted to analyse the structural characteristics of the mangrove community.The carbon storage and carbon density of different mangrove ecosystems were obtained based on the allometric growth equation of mangrove plants.The analysis yielded four main results.(1)The island group covers about 27.10 ha,41.32%(11.20 ha)of which represents mangrove areas.The mangrove forest is widely distributed in the tidal flats around the islands.(2)The main mangrove types were Aegiceras corniculatum,Kandelia obovata+Aegiceras corniculatum,Avicennia marina+Aegiceras corniculatum and Avicennia marina communities.(3)Amongst the mangrove plants,Avicennia marina had the highest biomass(18.52 kg plant^(–1)),followed by Kandelia obovata(7.84 kg plant^(–1))and Aegiceras corniculatum(3.85 kg plant^(–1)).(4)The mangrove carbon density difference was significant.Kandelia obovata had the highest carbon density(148.03 t ha^(–1)),followed by Avicennia marina(104.79 t ha^(–1))and Aegiceras corniculatum(99.24 t ha^(–1)).The carbon storage of the mangrove island ecosystem was 1194.70 t,which was higher than in other areas with the same latitude.The carbon sequestration capacity of the mangrove was relatively strong. 展开更多
关键词 MANGROVES island communities structural characteristics biomass carbon storage
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Composition and Spatial Distribution of Soil Mesofauna Along an Elevation Gradient on the North Slope of the Changbai Mountains, China 被引量:6
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作者 JIANG Yunfeng YIN Xiuqin WANG Fubin 《Pedosphere》 SCIE CAS CSCD 2015年第6期811-824,共14页
The Changbai Mountains, located in northeastern China, show clear vertical zonation of vegetation types. Six different habitats,namely Pinus koraiensis mixed broad-leaved forest, Pinus koraiensis-Picea forest, spruce-... The Changbai Mountains, located in northeastern China, show clear vertical zonation of vegetation types. Six different habitats,namely Pinus koraiensis mixed broad-leaved forest, Pinus koraiensis-Picea forest, spruce-fir forest, Betula ermanii forest, alpine meadow and alpine semi-desert, at elevations ranging from 780 to 2 480 m, covering almost all ecosystems on the north slope of the Changbai Mountains, were investigated to determine: i) whether or not the community composition of soil mesofauna varied significantly at different elevations; ii) if different soil mesofauna groups would respond differently to elevation and iii) which factors influenced the spatial distribution of soil mesofauna along elevation. Soil mesofauna were collected from each habitat in spring(May),summer(July) and autumn(September) of 2009. The soil mesofauna communities were comprised of at least 44 groups and were dominated by Acari and Collembola, followed by Coleoptera, Diptera larvae and Enchytraeidae. The composition, diversity and abundance of soil mesofauna varied among the six habitats. Meanwhile, significant seasonal variations were observed in the composition,abundance and diversity of the soil mesofauna in each habitat. The taxonomic richness and Shannon index were affected by elevation and soil properties, while the abundance was only significantly affected by soil properties. With regard to taxa, the habitats and seasons had significant effects on almost all the abundances of the major taxonomic groups. The abundance of more taxonomic groups was significantly influenced by the soil properties, while those of Geophilomorpha, Araneae and other taxa were affected by elevation.It is concluded that the composition and spatial distribution of the soil mesofauna varied along the elevation gradient on the north slope of the Changbai Mountains, which might be largely related to the variations of the plant community, soil properties and climate change resulting from the elevation gradient. 展开更多
关键词 ABUNDANCE community composition diversity environmental factors taxonomic group
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