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“生态性”理念与高等教育管理浅论 被引量:6
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作者 陈小华 《河南社会科学》 CSSCI 北大核心 2011年第3期188-190,共3页
"生态"通常意味着一个彼此相连且不可分割的有机系统。只有各个组成部分(因素)之间和谐运作,高等教育又好又快发展才会成为可能。高等教育管理中的"生态性"理念,包括在高等教育管理过程之中强调人的主观能动性"... "生态"通常意味着一个彼此相连且不可分割的有机系统。只有各个组成部分(因素)之间和谐运作,高等教育又好又快发展才会成为可能。高等教育管理中的"生态性"理念,包括在高等教育管理过程之中强调人的主观能动性"、自我"实现、学术知觉、自由与责任等基本特征。与上述特征相一致的管理方式就要符合生态性原则。高等教育诸要素的和谐统一,便是"生态性"理念在高等教育管理中的体现。 展开更多
关键词 “生态性”理念 高等教育管理 和谐统一
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高职院校“生态性”声乐课堂的构建初探 被引量:2
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作者 潘丽 《音乐时空》 2014年第15期138-139,共2页
近年来,生态、和谐、可持续发展等关键词,已经成为了当代人的共识。作为高职院校的声乐教学来说也不例外,如何在现有的基础上打造出一个生态化的教学环境,继而使教学质量得到本质的提升,成为了一个声乐教育界的新课题。鉴于此,本文从&qu... 近年来,生态、和谐、可持续发展等关键词,已经成为了当代人的共识。作为高职院校的声乐教学来说也不例外,如何在现有的基础上打造出一个生态化的教学环境,继而使教学质量得到本质的提升,成为了一个声乐教育界的新课题。鉴于此,本文从"生态性"声乐课堂的含义和意义谈起,从教学目标、教学内容、教学方式和教学评价等多个方面,就高职院校"生态性"声乐课堂的构建进行了初步的探索。 展开更多
关键词 高职院校 “生态性” 声乐课堂
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中国纺织业如何生态突围 被引量:2
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作者 黄勇 《环境导报》 2003年第2期14-14,共1页
关键词 出口商品 “生态性”检测 中国 纺织业 生态毒性物质 绿色认证
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Ecological Assessment on the Introduced Sonneratia caseolaris and S. apetala at the Mangrove Forest of Shenzhen Bay, China 被引量:12
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作者 昝启杰 王伯荪 +1 位作者 王勇军 李鸣光 《Acta Botanica Sinica》 CSCD 2003年第5期544-551,共8页
yTwo exotic species, Sonneratia caseolaris (L.) Engl. and S. apetala B. Ham., were introduced to Futian Mangrove Forest Nature Reserve, Shenzhen Bay, in 1993 for afforestation. Winter cold caused frigid harm but did n... yTwo exotic species, Sonneratia caseolaris (L.) Engl. and S. apetala B. Ham., were introduced to Futian Mangrove Forest Nature Reserve, Shenzhen Bay, in 1993 for afforestation. Winter cold caused frigid harm but did not appear to be an obstacle to the introduction. The cold tolerance of the parental and filial generation increased in several years. The two Sonneratia spp. could propagate by seeds and disperse in Shenzhen Bay. While the two species grew faster than indigenous species, at the same time they promoted the growth of indigenous species, but they could not replace indigenous mangrove species. Suitable habitat was more important than the distance from the source in the natural spreading for the two species. The niche of the two species did not overlap with the niche of indigenous species. The two species did not self regenerate, although they could disperse on localized area in Shenzhen Bay. Therefore, it was unlikely that the two species would pose ecological disaster. 展开更多
关键词 Sonneratia caseolaris Sonneratia apetala ecological adaptability ecological invasion
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Association of Polymorphisms of Leptin Gene with Body Weight and Body Sizes Indexes in Chinese Indigenous Cattle 被引量:8
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作者 杨东英 陈宏 +6 位作者 王新庄 田志环 唐立刚 张争锋 雷初朝 张良志 王轶敏 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第5期400-405,共6页
PCR-SSCP was used to analyze the polymorphism of leptin gene in 539 samples of six cattle breeds, namely Nanyang (NY), Qinchuan (QC), Jiaxianred (JXR), Xizhen (XZ), Luxi (LX), and Holstein cow (HOL) breeds... PCR-SSCP was used to analyze the polymorphism of leptin gene in 539 samples of six cattle breeds, namely Nanyang (NY), Qinchuan (QC), Jiaxianred (JXR), Xizhen (XZ), Luxi (LX), and Holstein cow (HOL) breeds. PCR products with a 330 bp were amplified and sequenced. The results showed that the frequencies of alleles A/B of NY, QC, JXR, XZ, LX, and HOL breeds were 0.558/0.442, 0.492/0.508, 0.571/0.429, 0.658/0.342, 0.591/0.409, and 0.615/0.385, respectively. The association of variations of leptin gene with growth traits in NY, QC, JXR breeds was analyzed. Some indexes of the individuals with genotype BB were higher than that with genotype AA and AB in NY breed, such as the indexes of body length, heart length, body weight, hucklebone width, body height, and average day gain. The height at hip cross of the individuals with genotype BB was higher than that of those with genotype AA and AB in QC breed (P 〈 0.05). So leptin gene may be one of the candidate genes for growth traits with height at hip cross, but not for body weight, heart length, and body length trait. However, the height at hip cross and hucklebone width of the individuals with genotype AB and BB were higher than that of those with genotype AA in JXR breed (P 〈 0.05), but the difference was not statistically significant in body weight and body sizes (body height, body length, and heart length). And the polymorphisms in leptin gene were caused by G→T transversion at the 66th bp position, A→C transversion at the 67th bp position and G→T transversion at the 299th bp position. These results may be applied to marker-assisted selection of Chinese cattle breeds. 展开更多
关键词 Chinese indigenous cattle leptin gene PCR-SSCP POLYMORPHISM growth traits
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Ecological adaptation of Eupatorium adenophorum populations to light intensity 被引量:6
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作者 孙晓玉 陆兆华 +2 位作者 李鹏辉 姜骑山 梁震 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期116-120,共5页
Eupatorium adenophorum is one of main invasive plants in China and has caused great economic losses. A study was conducted to determine the biomass allocation, leaf morphology and growth response of E. adenophorum see... Eupatorium adenophorum is one of main invasive plants in China and has caused great economic losses. A study was conducted to determine the biomass allocation, leaf morphology and growth response of E. adenophorum seedlings that grew under five different intensities (relative irradiances RI 10%, 20 %, 30%, 55%, 100%) for 14 months. Results reveal that the species shows typical leaf morphological adaptation to different light conditions. The total biomass of seedlings increased with the increase of light intensity from 10% to 55% RI but decreased at RI 100% (full sunlight). Height growth increased with the increase of light intensity from 10% to 30% RI but decreased when light intensity was over 30% RI. At low light levels, plants enhanced light availability by means of increasing biomass allocation to leaves and formation of larger, thinner leaves with high specific leaf area (SLA), leading to a high leaf area ratio (LAR) and high stem strips length (SSL). The mean relative growth rate (RGR) of the plant increased with the light intensity increase and attained the maximum at 55% RI. The growth of seedlings at 30%-55% RI was much better than that at full light condition. This might be an adaptive strategy that supports the vigorous invasiveness of this species, because a high-shaded canopy could prevent other plant species from surviving and growing. This study indicates that E. adenophorum could adapt to different light conditions, especially to low light habit. This can explain its greater invasiveness. 展开更多
关键词 Ecological adaptation Eupatorium adenophorum INVASIVENESS Light intensity
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Relationship Between Ecophysiological Features and Grain Yield in Different Soybean Varieties 被引量:13
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作者 朱桂杰 蒋高明 +4 位作者 郝乃斌 刘合芹 孔正红 杜维广 满为群 《Acta Botanica Sinica》 CSCD 2002年第6期725-730,共6页
Photosynthetic rate ( P n ), transpiration rate ( E ), stomatal conductance ( g s ), water use efficiency ( WUE ), intercellular CO 2( C i ) and leaf water potential ( Ψ ) in varieties of soybean ( G... Photosynthetic rate ( P n ), transpiration rate ( E ), stomatal conductance ( g s ), water use efficiency ( WUE ), intercellular CO 2( C i ) and leaf water potential ( Ψ ) in varieties of soybean ( Glycine max (L.) Merr.) measured in the past three decades (1970s, 1980s and 1990s) and their inter_relationships were analyzed. These parameters of soybean changed with development stages. It is shown that there was a strongly positive relationship between the yield of soybean and its net photosynthetic rate. Soybean varieties with high yield potential had higher P n , g s and Ψ than those with low yield potential. Their values of C i were remarkably lower. Such relationship was especially remarkable at the critical stage of pod_bearing. P n of soybean of high yield was obviously higher than that of low yield. Of the different stages, the highest P n was found in the pod_bearing stage and other values were higher, too. P n and Ψ of modern soybean varieties were higher and such was continuing. Increased partitioning of carbon to seed and the size of sink may also be important for yield formation when P n values were remarkably higher in the pod_bearing stage. 展开更多
关键词 SOYBEAN ecophysiological characteristics photosynthetic rate stomatal conductance water potential
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Organic Acids Secreted from Plant Roots under Soil Stress and Their Effects on Ecological Adaptability of Plants 被引量:11
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作者 黄文斌 马瑞 +2 位作者 杨迪 刘星平 宋金凤 《Agricultural Science & Technology》 CAS 2014年第7期1167-1173,共7页
[Objective] In this study,the secretion of organic acids from plant roots under soil nutrient and water stress and the effects of organic acids on ecological adaptability of plants were investigated,which provided the... [Objective] In this study,the secretion of organic acids from plant roots under soil nutrient and water stress and the effects of organic acids on ecological adaptability of plants were investigated,which provided theoretical basis for improving the adaptability of plants to a variety of stress conditions.The results showed that,under nutrient and water stress,the content of organic acids secreted from plant roots increased significantly as a common active adaptive response.Organic acids could improve the activities of a variety of antioxidant enzymes,contents of osmotic regulatory substances,contents of chlorophyll and photosynthesis levels,promote nutrient absorption and transportation in plants,and ultimately contribute to plant growth and biomass accumulation,reduce the toxicity of stress conditions to plants and improve the stress resistance and adaptability of plants. 展开更多
关键词 Nutrient stress Water stress Organic acids secreted from plant roots Plant ecological adaptability
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Analysis of Climatic Factors Causing Yield Difference in Ramie among Different Eco-regions of Yangtze Valley 被引量:3
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作者 刘头明 汤清明 +1 位作者 朱四元 唐守伟 《Agricultural Science & Technology》 CAS 2011年第5期745-750,共6页
[Objective] This study was to investigate the climatic factors affecting the regional eco-adaptability of ramie.[Method] Five experimental sites of different eco-types in ramie growing regions in Yangtze Valley were s... [Objective] This study was to investigate the climatic factors affecting the regional eco-adaptability of ramie.[Method] Five experimental sites of different eco-types in ramie growing regions in Yangtze Valley were set up to investigate the yield of Zhongzhu No.2,based on which we assessed the adaptability of Zhongzhu No.2 to various eco-regions and further analyzed the climatic factors causing the difference in eco-adaptability.[Result] Ramie yield varied largely among various experimental sites and the yield difference appeared to be well repeatable,with a differential value between the maximum and the minimum reaching 2.3 kg/20 m2.Analysis of the yield data,together with climatic factors in various ecological regions showed that yield of Zhongzhu No.2 was significantly correlated with rainfall,sunshine hours,relative humidity during its growing period.Of the climatic factors,sunshine hours and rainfall can positively promote yield increase,while relative humidity negatively regulate ramie yield.[Conclusion] The climatic indices,including rainfall,sunshine duration and relative humidity are a key factor causing yield difference in ramie among different regions of Yangtze Valley. 展开更多
关键词 RAMIE Eco-adaptability Climatic factor
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Effects of Probiotics on Growth Performance and Blood Biochemical Indexes of Cherry Valley Ducks 被引量:4
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作者 李小芬 杨晓志 +3 位作者 陶勇 张玲 顾文婕 袁旭红 《Agricultural Science & Technology》 CAS 2015年第8期1732-1734,1740,共4页
In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. To... In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. Total 240 1-d-old Cherry Valley ducks were selected, and they were randomly divided into 4 groups, including 1 control group and 3 treatment groups. There were 3 replicates for each group and there were 20 ducks for each replicate. The ducks in the control group were fed the basal diet, and the ducks in the 3 treatment groups were fed the basal diet added with Lactobacillus, Bacillus natto and florfenicol, respectively. The test lasted for 42 d. The results showed that the addition of Lactobacillus and Bacillus natto could improve the average daily weight gain and final average weight (P〈0.05) of Cherry Valley ducks, and reduce the glutamic-pyruvic transaminase ac- tivity, alkaline phosphatase activity and serum urinary nitrogen content in duck blood (P〈0.05) and reduce the creatinine content and total cholesterol content in Cherry Valley ducks (P〉0.05); at the same time, adding probiotics to feed could also in- crease the grass economic benefits of Cherry Valley ducks. In overall, the effects of adding probiotics were better than those of adding antibiotic. 展开更多
关键词 Cherry Valley duck Probiotic Growth performance Blood biochemicalindex Economic benefits
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Responses of the seedlings of five dominant tree species in Changbai Mountain to soil water stress 被引量:1
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作者 代力民 李秋荣 +1 位作者 王淼 姬兰柱 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期191-196,共6页
Soil water stress was studied on the potted seedlings of five dominant tree species (Pinus koraienes Sieb.et Zucc., Fraxinus mandshurica Rupr., Juglans mandshurica Maxim, Tilia amurensis Rupr. and Quercus mongolica Fi... Soil water stress was studied on the potted seedlings of five dominant tree species (Pinus koraienes Sieb.et Zucc., Fraxinus mandshurica Rupr., Juglans mandshurica Maxim, Tilia amurensis Rupr. and Quercus mongolica Fisch.ex Turcz) from the broadleaved/Korean pine forest in Changbai Mountain. Leaf growth, water transpiration and photosynthesis were compared for each species under three soil moisture conditions: 85%-100% (high water, CK), 65%-85% (Medium water, MW) and 45%-65% (low water, LW) of 37.4% water-holding capacity in field. The results showed that the characteristic of typical drought-resistance of the leaves is significantly developed. The net photosynthetic rate and water use efficiency of Fraxinus mandshurica were higher in MW than those in CK. But for the other four species, the net photosynthetic rate and water use efficiency in CK were lower than those in MW and LW. The transpiration rate responding to soil moistures varied from species to species. 展开更多
关键词 Water stress Net photosynthesis Transpiration rate Water use efficiency Broadleaf/Korean pine forest
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Advances in Research on the Structure and Diversity Variation of Insect Communities in Wetland 被引量:1
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作者 刘佳妮 张瑜愉 +5 位作者 徐松萍 赵晓红 尹利方 华金珠 姚丽媛 郭丽红 《Agricultural Science & Technology》 CAS 2017年第5期914-917,956,共5页
The species diversity, structure and dynamic rules of insect communities in wetland can provide data of the insects for the protection, utilization and monitor- ing of wetland, which is an essential link to maintain t... The species diversity, structure and dynamic rules of insect communities in wetland can provide data of the insects for the protection, utilization and monitor- ing of wetland, which is an essential link to maintain the healthy ecological system of the wetland and protect the biodiversity in the wetland. A systematic study on the composition and succession of insect communities in the wetland, as well as the indication of insect groups can provide a theoretical basis for wetland protection and management, and thus promote the development of regional economy and en- vironmental protection. 展开更多
关键词 WETLAND Insect community BIODIVERSITY ECOSYSTEM
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Comparative study on three dynamic modulus of elasticity and static modulus of elasticity for Lodgepole pine lumber 被引量:5
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作者 梁善庆 傅峰 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期309-312,共4页
The dynamic and static modulus of elasticity (MOE) between bluestained and non-bluestained lumber of Lodgepole pine were tested and analyzed by using three methods of Non-destructive testing (NDT), Portable Ultras... The dynamic and static modulus of elasticity (MOE) between bluestained and non-bluestained lumber of Lodgepole pine were tested and analyzed by using three methods of Non-destructive testing (NDT), Portable Ultrasonic Non-destructive Digital Indicating Testing (Pundit), Metriguard and Fast Fourier Transform (FFT) and the normal bending method. Results showed that the dynamic and static MOE of bluestained wood were higher than those of non-bluestained wood. The significant differences in dynamic MOE and static MOE were found between bulestained and non-bluestained wood, of which, the difference in each of three dynamic MOE (Ep. the ultrasonic wave modulus of elasticity, Ems, the stress wave modulus of elasticity and El, the longitudinal wave modulus of elasticity) between bulestained and non-bluestained wood arrived at the 0.01 significance level, whereas that in the static MOE at the 0.05 significance level. The differences in MOE between bulestained and non-bluestained wood were induced by the variation between sapwood and heartwood and the different densities of bulestained and non-bluestained wood. The correlation between dynamic MOE and static MOE was statistically significant at the 0.01 significance level. Although the dynamic MOE values of Ep, Em, Er were significantly different, there exists a close relationship between them (arriving at the 0.01 correlation level). Comparative analysis among the three techniques indicated that the accurateness of FFT was higher than that of Pundit and Metriguard. Effect of tree knots on MOE was also investigated. Result showed that the dynamic and static MOE gradually decreased with the increase of knot number, indicating that knot number had significant effect on MOE value. 展开更多
关键词 Lodgepole pine Non-destructive testing Dynamic modulus of elasticity Static modulus of elasticity
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Research Progress on Genetic Diversity and Its Ecological Conservation of Endangered Dongxiang Wild Rice (Oryza rufipogon Griff.) 被引量:1
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作者 胡标林 万勇 +3 位作者 李霞 蔡耀辉 罗向东 谢建坤 《Agricultural Science & Technology》 CAS 2012年第1期113-119,197,共8页
It is of great importance for the analysis on genetic evolution mechanism, and rice breeding utilization by estimation and protection of genetic diversity of pre- sent DXWR (Oryza rufipogon Griff.). This study has s... It is of great importance for the analysis on genetic evolution mechanism, and rice breeding utilization by estimation and protection of genetic diversity of pre- sent DXWR (Oryza rufipogon Griff.). This study has summarized genetic diversity and protection achievements of DXWR from many aspects like varied conservations, years, generations, other species of wild rice and cultivated rice. In this study, a u- nified and scientific evaluation system of genetic diversity is encouraged to be built and suggestions on research prospect and ecological conservation of DXWR genetic diversity have been proposed. 展开更多
关键词 Dongxiang wild rice (Oryza rufipogon Griff.) Genetic diversity Ecological conservation
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Evaluation on Wheat Adaptability in Hetao Area,Inner Mongolia 被引量:2
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作者 侯俊琳 赵锁志 彭志帆 《Agricultural Science & Technology》 CAS 2016年第10期2377-2382,共6页
Wheat samples were collected from Hetao Area, Inner Mongolia, and their poisonous, harmful and beneficial elements contents were analyzed. According to the standards for heavy metals in wheat green food, the Hg, Cd, A... Wheat samples were collected from Hetao Area, Inner Mongolia, and their poisonous, harmful and beneficial elements contents were analyzed. According to the standards for heavy metals in wheat green food, the Hg, Cd, As and Pb contents in the wheat samples collected from Qiantao Area were all below the national standards, indicating that they were green; and the heavy metals contents in the wheat samples collected from Houtao Area were basically in line with the pollutionfree food hygiene standards, indicating that they were not harmful to human body. Harmful elements Cd and Hg were more enriched in the wheat samples from Qiantao Area, but their contents were all lower than the national food standards, indicating that the wheat from Qiantao Area was not harmful to human health. The wheat from Houtao Area was rich in essential trace elements Cu, Zn, Se and K, and long-term consumption was beneficial to human health. 展开更多
关键词 WHEAT ADAPTABILITY Ecological effect EVALUATION
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Diversity of Sucking Lice on Small Mammals in the Surrounding Areas of Erhai Lake in Yunnan,China 被引量:3
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作者 董文鸽 郭宪国 +2 位作者 门兴元 钱体军 吴滇 《Entomotaxonomia》 CSCD 北大核心 2009年第1期68-80,共13页
An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were c... An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were captured and identified into 7 families, 15 genera and 21 species in 4 orders (Rodentia, Insectivora, Scandentia and Carnivora), while t4 635 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 5 families, 6 genera and 21 species in the Order Anoplura, The sites stand alongside three cordilleras surrounding the Erhai Lake, namely Eastern Wuliang Mountain, Southern Ailao Mountain and Western Cangshan Mountain. The three confined oriented areas are different landscapes within the same zone where the longitude, latitude, altitude and fauna are homologous but isolated by Erhai Lake as inartificial barrier. The aim of this study was to recognize features of the species diversity, abundance, community structure, similarity and distribution of sucking lice in different landscapes within the same zone. The results showed the species diversity of sucking lice was very low with a very simple community structure. The distribution of sucking lice and their corresponding hosts are quite uneven among different oriented areas and this may imply that ecological environment influences the species composition and distribution of sucking lice and their corresponding hosts. A certain species of hosts usually have their fixed louse species. The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. Species of sucking lice on the same small mammal host in different oriented areas of Erhai Lake are homologous. The results strongly suggest a close relationship of co-evolution between sucking lice and their hosts. 展开更多
关键词 ANOPLURA small mammal species diversity community ecology co-evolution.
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Application of N: P Stoichiometry to Ecology Studies 被引量:86
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作者 张丽霞 白永飞 韩兴国 《Acta Botanica Sinica》 CSCD 2003年第9期1009-1018,共10页
Stoichiometry has long been addressed in the studies of ecosystem ecology, but it was almost ignored for a long time. Until recently, ecologists have become aware that stoichiometry could provide a new tool to study e... Stoichiometry has long been addressed in the studies of ecosystem ecology, but it was almost ignored for a long time. Until recently, ecologists have become aware that stoichiometry could provide a new tool to study ecology from genes to the biosphere. Among this trend, N:P stoichiometry is used actively in ecological interactions since nitrogen (N) and phosphorus (P) are the two most important elements in most ecosystems. This article reviews the application of N:P stoichiometry to the studies of ecological problems at different levels, including ecosystem, community and species. Meanwhile, we also provide the cellular basis of N:P stoichiometry, identify the shortages in the use of N:P stoichiometry theory, and put forward some perspectives for future research to be conducted. 展开更多
关键词 trophic interaction trophic dynamics ecological interactions nutrient limitation
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Status of urban vegetation in Guangzhou City 被引量:12
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作者 管东生 陈玉娟 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期249-252,共4页
According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey f... According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey for soil, species di-versity, roadside trees and ecological function of urban vegetation in Guangzhou City. The results showed that: (1) soil densi-ties of urban roadside and park forests were higher than mean density of natural forest soil. The pH values of soil in urban roadside were higher too, and the content of organic matter and the concentration of nitrogen were lower. (2) Species diversity of urban vegetation was lower. The most number of species was only 16 species in tree layers of urban forest. (3) Tree growth was limited by narrow space in high-density urban area, where the trees with defects and disorders were common. (4) Com-paring with mature natural forests, the productivity of urban vegetation was lower. The effect of urban vegetation on balance of carbon and oxygen were influenced by the low primary production of urban vegetation. Therefore, the growth condition for urban vegetation should be improved. Biodiversity, primary production and ecological function should be increased for urban vegetation in order to improve urban eco-environment. 展开更多
关键词 Urban vegetation STATUS Human impact
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Research Progress of Vulnerability Assessment on Grassland Ecosystem under Climate Change 被引量:2
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作者 运向军 侯向阳 +1 位作者 刘桂香 尹燕亭 《Agricultural Science & Technology》 CAS 2012年第10期2186-2190,2230,共6页
[Objective] The aim was to review on vulnerability evaluation of grassland ecosystem under climate change.[Method] In the research,vulnerability evaluation methods of ecosystem under climate changes,at home and abroad... [Objective] The aim was to review on vulnerability evaluation of grassland ecosystem under climate change.[Method] In the research,vulnerability evaluation methods of ecosystem under climate changes,at home and abroad,and the related cases and research progress in China were reviewed.In addition,the future of evaluation research was predicted.[Result] Ecosystem vulnerability to climate change is an important part of climate change research.It is necessary and urgent to improve evaluation methods and reduce uncertainty of future vulnerability evaluation to make evaluation more comprehensive and objective.Furthermore,evaluation on effects of human activity on natural ecosystem vulnerability should be highlighted.[Conclusion] The research provided reference for establishment of a new management model for ecosystem adaptability to climate and sustainable development of grasslands in northern China. 展开更多
关键词 Climate change VULNERABILITY Grassland ecosystem
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Study on Application of Microbial Ecological Agents, Replacements for Antibiotics, in Weaned Piglet Production 被引量:1
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作者 乔利敏 乔富强 +4 位作者 关文怡 张京和 肖西山 姚华 杨久仙 《Agricultural Science & Technology》 CAS 2015年第4期757-760,共4页
In order to investigate the appIication effects of microbial ecoIogical agents as repIacements for antibiotics in weaned pigIets, a total of 120 28 d oId healthy Duroc &#215;Landrace &#215;Large White weaned pigIets... In order to investigate the appIication effects of microbial ecoIogical agents as repIacements for antibiotics in weaned pigIets, a total of 120 28 d oId healthy Duroc &#215;Landrace &#215;Large White weaned pigIets with simiIar bogy weights and body fats and cIose birth dates were seIected. They were randomIy divided into three groups, incIuding controI group (CK), antibiotic group (A) and microbial ecoIogical agent group (MEA). The growth performance, health status and economic benefits of the weaned pigIets were measured. The resuIts showed that the A and MEA groups couId better enhance the immunity of weaned pigIets and improve the economic benefits in the whoIe experimental period compared to the CK group (P〈0.01). How-ever, there were no significant differences in pigIet immunity and economic benefits between the A and MEA groups (P〉0.05). It is indicated that the Rujunbao, a mi-crobial ecoIogical agent, can be promoted in weaned pigIet production as a repIace-ment for antibiotic. 展开更多
关键词 Microblal ecological agent Weaned piglet Growth performance Disease resistance Economic benefit
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