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弗罗斯特小诗《牧场》有大美
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作者 谭家善 《最小说》 2024年第6期7-11,共5页
罗伯特·弗罗斯特的《牧场》一诗,只有八行,还包括一个括号和两个重复的句子,可谓微型小诗了。但它有大美:首先,是淡而有味的富于变化的节奏和声调,这淡而有味的声调,成就了古代美学家司空图提出的一个诗的“全美”标准,即“味外之... 罗伯特·弗罗斯特的《牧场》一诗,只有八行,还包括一个括号和两个重复的句子,可谓微型小诗了。但它有大美:首先,是淡而有味的富于变化的节奏和声调,这淡而有味的声调,成就了古代美学家司空图提出的一个诗的“全美”标准,即“味外之旨”;其次,它的淡泊之美,同时又成就了中国美学的重要命题,即“大巧若拙”。 展开更多
关键词 罗伯特·弗罗斯特 《牧场》 淡泊之美 味外之旨
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《牧场》的隐喻揭密弗罗斯特诗艺特色
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作者 孙幼萍 《湖北经济学院学报(人文社会科学版)》 2009年第12期101-103,共3页
罗伯特·弗罗斯特的《牧场》以自然富有乐感的口语和众多隐喻映射诗人创作的理念。作为诗集序言诗,《牧场》成为诗歌创作的象征。诗人将自己的才智与追求,通过诗歌审美技巧构建了乡村田园的精神栖息地,以探索人类最好的生存方式,而... 罗伯特·弗罗斯特的《牧场》以自然富有乐感的口语和众多隐喻映射诗人创作的理念。作为诗集序言诗,《牧场》成为诗歌创作的象征。诗人将自己的才智与追求,通过诗歌审美技巧构建了乡村田园的精神栖息地,以探索人类最好的生存方式,而诗歌也成就了这位大诗人。 展开更多
关键词 《牧场》 诗艺 隐喻 序言诗
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“生动”345课堂教学模式在小学语文教学中的创新应用——以《牧场之国》为例
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作者 何理连 《求知导刊》 2024年第32期32-34,103,共4页
以“生动”345课堂教学模式为理论框架,探讨该模式在小学语文教学中的创新应用。基于《牧场之国》的教学实践进行实证研究,分析该模式在提升教学效果、促进学生主动学习方面的实际效果。研究表明,“生动”345课堂教学模式能够有效激发... 以“生动”345课堂教学模式为理论框架,探讨该模式在小学语文教学中的创新应用。基于《牧场之国》的教学实践进行实证研究,分析该模式在提升教学效果、促进学生主动学习方面的实际效果。研究表明,“生动”345课堂教学模式能够有效激发学生的学习兴趣,提高他们的自主学习能力,进而优化整体教学。“生动”345课堂教学模式不仅能为小学语文教学模式的创新提供有益参考,也能为其他学科的课堂教学改革提供借鉴和启示。 展开更多
关键词 “生动”345课堂 小学语文 《牧场之国》
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牧场
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作者 罗伯特.弗罗斯特 朱积汉 《中学生英语(初中版)》 2002年第16期I001-I001,共1页
I'm going to clean the pasture spring.I'll only stop to rake the leaves away(And wait to watch the water clear,I may),I shon't be gone long.—You come too.
关键词 《牧场》 罗伯特·弗罗斯特 美国 英文诗歌 初中 英语 双语阅读
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试析清代东北养息牧牧场的变迁及影响 被引量:4
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作者 关亚新 《史学集刊》 CSSCI 北大核心 2008年第3期86-93,共8页
养息牧牧场是清王朝设在东北柳条边外的惟一皇家牧场,畜养大量的牛羊马,不仅供应盛京三陵祭祀之用和补给八旗官马之需,而且部分产品成为清皇室的贡品。这座几乎伴随清王朝始终的皇家牧场,它的设立、发展、试垦、续垦和放垦演绎了养息牧... 养息牧牧场是清王朝设在东北柳条边外的惟一皇家牧场,畜养大量的牛羊马,不仅供应盛京三陵祭祀之用和补给八旗官马之需,而且部分产品成为清皇室的贡品。这座几乎伴随清王朝始终的皇家牧场,它的设立、发展、试垦、续垦和放垦演绎了养息牧牧场恢复、繁盛、衰落和消失的全过程。 展开更多
关键词 清代 养息牧 牧场 变迁
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读写结合“教、学、评”一体化的困境与突破——以五年级下册《牧场之国》为例 被引量:2
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作者 许惠芳 《语文建设》 北大核心 2023年第14期31-35,共5页
读与写是语文课程培养学生应具备的基本能力,统编教材鲜明地呈现了读与写的内在联系。解构教材,不难发现其读写结合指向“教、学、评”一体化的设计思路。但囿于教材理解的偏位、学情分析的不足等原因,读与写结合教学出现了失衡的多重... 读与写是语文课程培养学生应具备的基本能力,统编教材鲜明地呈现了读与写的内在联系。解构教材,不难发现其读写结合指向“教、学、评”一体化的设计思路。但囿于教材理解的偏位、学情分析的不足等原因,读与写结合教学出现了失衡的多重困境。针对现实问题,读写结合“教、学、评”一体化可以通过在阅读中提升语感,在归类中探究写法,在评价中深化建构,使“教”有道、“学”得法、“评”遵章,推动学生阅读能力和习作能力的双重提升。 展开更多
关键词 读写结合 “教、学、评”一体化 《牧场之国》
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牧场(外一首)
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作者 罗寒 《当代教育》 2010年第4期93-93,共1页
人到中年。
关键词 中学 作文 语文教学 《牧场(外一首)》
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从“三美”原则看英格律诗汉译 被引量:1
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作者 陈倩 《山东省农业管理干部学院学报》 2005年第2期128-129,共2页
本文通过比较弗罗斯特的格律诗《牧场》的三种中译文,探讨许渊冲的“三美”原则在英格律诗汉译中的应用。诗是内容和形式高度融合的有机统一体,格律诗更是借形以传神。尽管不存在最理想的或不可替代的翻译策略,“三美”原则可能会引导... 本文通过比较弗罗斯特的格律诗《牧场》的三种中译文,探讨许渊冲的“三美”原则在英格律诗汉译中的应用。诗是内容和形式高度融合的有机统一体,格律诗更是借形以传神。尽管不存在最理想的或不可替代的翻译策略,“三美”原则可能会引导译者更好地接近原文。 展开更多
关键词 英国 格律诗 英语 汉语 文学翻译 “意美”原则 “音美”原则 “形美”原则 弗罗斯特 《牧场》
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Screening and Efficacy Observation of Traditional Chinese Medicine Against Chicken Pathogenic Escherichia coli 被引量:18
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作者 庞向红 褚秀玲 +3 位作者 苏建青 梁淑珍 李全福 胡满 《Agricultural Science & Technology》 CAS 2009年第1期140-144,共5页
[ Objective] The aim of this study was to lay a foundation for obtaining effective traditional Chinese medicine preparations controlling chicken colibacillosis. [ Method] With the western medicine Lomeflbxacin Hydroch... [ Objective] The aim of this study was to lay a foundation for obtaining effective traditional Chinese medicine preparations controlling chicken colibacillosis. [ Method] With the western medicine Lomeflbxacin Hydrochloride and Sodium Chloride Injection as the control, drug sensitivity tests of 15 single traditional Chinese herbs and seven self-made Chinese herbal compounds were conducted. Subsequently, the single traditional Chinese herbs presenting good in vitro antibacterial effects against Escherichia coli and all the seven compounds were given to the chicks artificially infected with E. coil to observe their efficacies. [ Result] The results of drug sensitivity tests showed that all the 15 traditional Chinese herbs had certain antibacterial effect against E. coli, among which aloe, pomegranate rind and radix sanguisorbae were the best. Compound 1, 2 and 5 had good antibacterial effects in vitro. By in vivo test, traditional Chinese medicines showed superior efficacies on infected chicks than western medicine, and compound 1 and 2 performed well. [ConclusiOn] Traditional Chinese medicine preparations are good at controlling Chicken colibacillosis, but their bacteriostasis mechanism in vivo was different with that in vitro. 展开更多
关键词 Traditional Chinese medicine preparation Drug sensitivity test Chicken colibacillosis In vivo test
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Influences of Family Ranches Management Mode on Plant Community Characteristic in Hulunber Meadow Steppe 被引量:1
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作者 闫瑞瑞 卫智军 +5 位作者 杨桂霞 韩国栋 辛晓平 卢志红 斯琴毕力格 吴宏军 《Agricultural Science & Technology》 CAS 2013年第11期1664-1669,共6页
[Objective] The aim was to explore the management mode on optimal re-sources al ocation of family ranch in meadow steppe. [Method] Three double repre-sentative family ranches were selected in meadow steppe of Hulunber... [Objective] The aim was to explore the management mode on optimal re-sources al ocation of family ranch in meadow steppe. [Method] Three double repre-sentative family ranches were selected in meadow steppe of Hulunber Old Barag Banner, and the study was carried out with the baseline survey. Three family ranches were selected as the demonstrative households for the corporation study, while other three family ranches with the similar conditions were looked as the non-demonstrative households for the comparison. Demonstrative households of the fami-ly ranches reduced the stocking rate, optimized the flock structure and took a winter feeding and other means to explore the different management models on plant com-munity characteristic of family ranch. [Result] The seasonal dynamic of community characteristic in family ranches showed the single-peaks curves. The seasonal dy-namics of community coverage, height and biomass in the demonstrative households showed higher compared with the non-demonstrative households, and community density in the experiment households was lower than that of the control experiment households. Community coverage, height and biomass of degraded grassland in family ranch have a great improve after optimization of management. Community coverage, height , density and biomass were increasing in fencing plot, but decreas-ing in free grazing area. Enclosure improved grassland coverage, vegetation height, density and forage yield. Leymus chinensis played an important role in plant com-munity. The important values of Leymus chinensis, Stipa baicalensis, Cleistogenes squarrosa, and Carex duriuscula were high. Leymus chinensis important value in the demonstrative households of optimal management was higher than that in the non-demonstrative households, and Carex duriuscula important value of the non-demon-strative households was significantly higher than that of the demonstrative house-holds. The indexes of Margalef richnes,Shannon-Wiener diversity, Simpson diversity and Pielou uniformity showed that the demonstrative households were higher than the non-demonstrative households. [Conclusion] The research provides theoretical ref-erences for sustainable development of pastures dominated by family ranch. 展开更多
关键词 Family ranches Management mode Hulunber meadow steppe Community characteristic
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Effect of thatch on water-soluble phosphorus of pasture soil fertilized with broiler litter
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作者 陈欣 张庆忠 M.L.Cabrera 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期71-73,共3页
The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory ... The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory study to evaluate the effect of a thatch layer on the dynamics of water-soluble P in undisturbed cores taken from a pasture. Cores with and without a thatch layer received a surface application of broiler litter (5 thm-2) and were incubated at 25 oC for 56 d. The result showed that on the soil surface the contents of water soluble-P (39 kghm-2) of the cores with the thatch layer was higher than that (20 kghm-2) of the cores without the thatch layer. Therefore on well-established pastures fertilized with broiler litter, the presence of a thatch layer might lead to high concentrations of water-soluble P on the soil surface. 展开更多
关键词 PASTURES Water-soluble phosphorus Broiler litter
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Modeling habitat suitability of range plant species using random forest method in arid mountainous rangelands 被引量:8
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作者 Hossein PIRI SAHRAGARD Majid AJORLO Peyman KARAMI 《Journal of Mountain Science》 SCIE CSCD 2018年第10期2159-2171,共13页
Mountainous rangelands play a pivotal role in providing forage resources for livestock, particularly in summer, and maintaining ecological balance. This study aimed to identify environmental variables affecting range ... Mountainous rangelands play a pivotal role in providing forage resources for livestock, particularly in summer, and maintaining ecological balance. This study aimed to identify environmental variables affecting range plant species distribution, ecological analysis of the relationship between these variables and the distribution of plants, and to model and map the plant habitats suitability by the Random Forest Method(RFM) in rangelands of the Taftan Mountain, Sistan and Baluchestan Province, southeastern Iran. In order to determine the environmental variables and estimate the potential distribution of plant species, the presence points of plants were recorded by using systematic random sampling method(90 points of presence) and soils were sampled in 5 habitats by random method in 0–30 and 30–60 cm depths. The layers of environmental variables were prepared using the Kriging interpolation method and Geographic Information System facilities. The distribution of the plant habitats was finally modelled and mapped by the RFM. Continuous maps of the habitat suitability were converted to binary maps using Youden Index(?) in order to evaluate the accuracy of the RFM in estimation of the distribution of species potentialhabitat. Based on the values of the area under curve(AUC) statistics, accuracy of predictive models of all habitats was in good level. Investigating the agreement between the predicted map, generated by each model, and actual maps, generated from fieldmeasured data, of the plant habitats, was at a high level for all habitats, except for Amygdalus scoparia habitat. This study concluded that the RFM is a robust model to analyze the relationships between the distribution of plant species and environmental variables as well as to prepare potential distribution maps of plant habitats that are of higher priority for conservation on the local scale in arid mountainous rangelands. 展开更多
关键词 Environmental (predictor) variables Habitat mapping Habitat distribution Random Forest Method Tartan Mountain
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Mountain Pastures and Grasslands in the SW Tien Shan,Kyrgyzstan-Floristic Patterns,Environmental Gradients,Phytogeography,and Grazing Impact 被引量:4
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作者 BORCHARDT Peter SCHICKHOFF Udo +1 位作者 SCHEITWEILER Sabrina KULIKOV Maksim 《Journal of Mountain Science》 SCIE CSCD 2011年第3期363-373,共11页
Vast grasslands are found in the walnut-fruit forest region of southern Kyrgyzstan,Middle Asia.Located above the worldwide unique walnutfruit forests and used for grazing,they play a pivotal role in the mixed mountain... Vast grasslands are found in the walnut-fruit forest region of southern Kyrgyzstan,Middle Asia.Located above the worldwide unique walnutfruit forests and used for grazing,they play a pivotal role in the mixed mountain agriculture of local farmers.Accordingly,these pastures are subject to an increasing utilization pressure reflecting the changing political and social conditions in the transformation process from a Soviet republic to an independent state.A first detailed analysis of mountain pasture vegetation in the Ferghana Range answers the following questions:What are the main plant community types among Kyrgyzstan's mountain pastures? What are the main environmental gradients that shape their species composition? Which phytogeographical distribution types are predominant? How does grazing affect community composition and species richness in these grasslands? Species composition was classified by cluster analysis;underlying environmental gradients were explored using DCA.A dataset of 395 relevés was used for classification,and a subset of 79 relevés was used in a DCA to analyze the correlation between vegetation,environment,and grazing impact.The investigated pastures were classified into four distinctive plant communities.The site factors altitude,heat load,inclination and grazing impact were found to be the major determinants of the vegetation pattern.A significant overlap between floristic composition and structural and spatial properties was shown.The majority of the species pool consisted of Middle Asian endemics and Eurosiberian species.However,disturbance-tolerant species played a significant role with respect to species composition and coverage of the herbaceous layer in vast areas of southern Kyrgyzstan's mountain pastures.In general,an intense grazing impact is clearly reflected by both species composition and structural variables of plant communities.The highly diverse and unique ecosystem is modified by an increasing utilization pressure.In order to maintain vital processes and functioning of this valuable ecosystem-in both economical and ecological terms-,it is indispensable to adopt appropriate pasture management strategies. 展开更多
关键词 Central Asia Classification ENDEMICS Gradient Analysis Grazing impact Middle Asia Pasture Management Ruderals Transformation Process Walnut-fruit forest.
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Ecogeomorphic Feedbacks in Semiarid Rangelands:A Review 被引量:5
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作者 I.STAVI H.LAVEE +1 位作者 E.D.UNGAR P.SARAH 《Pedosphere》 SCIE CAS CSCD 2009年第2期217-229,共13页
The ecogeomorphic processes occurring on semiarid rangelands are reviewed, with emphasis on the source-sink relations and positive feedback loops that existed between shrub patches and intershrub areas, and the way li... The ecogeomorphic processes occurring on semiarid rangelands are reviewed, with emphasis on the source-sink relations and positive feedback loops that existed between shrub patches and intershrub areas, and the way livestock presence affected these interactions. Compared with intershrub areas, the shrub patches had a higher soil porosity, infiltration capacity, water-holding capacity, hydraulic conductivity, structural stability, and organic matter content, and lower bulk density. These differences derived from a host of processes whose intensity was less in the shrub patches, including raindrop impact, mechanical crust formation, overland water flow, soil erosion, evaporative moisture loss, and flock trampling. There was also greater shading of the soil surface; soil and litter deposition; water accumulation; microbial, fungal, and mesofaunal activities in the shrub patches. The overland flow of water carried soil and litter from the intershrub areas to the shrub patches and resulted in microtopographic modifications that tended to strengthen these source-sink relations. Grazing had an impact on these processes, not only at the shrub-intershrub scale but also within the intershrub areas, through the creation of highly compacted trampling routes. The combined role of the above ecogeomorphic processes was to maintain the rangeland's functionality. Without these inter-relationships, water loss, soil erosion, and nutrient depletion would occur at the hillside scale, causing degradation of the landscape. 展开更多
关键词 intershrub areas SHRUBS soil resources trampling routes
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Impact of grazing on soil, vegetation and ewe production performances in a semi-arid rangeland 被引量:3
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作者 Muhammad ISLAM Abdul RAZZAQ +6 位作者 Shamim GUL Sarfraz AHMAD Taj MUHAMMAD Sawsan HASSAN Barbara RISCHKOWSKY M.N.M.IBRAHIM Mounir LOUHAICHI 《Journal of Mountain Science》 SCIE CSCD 2018年第4期685-694,共10页
Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics,... Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics, aboveground vegetation biomass dynamics and controlled grazinginduced changes in the live weight of local ewes in the semi-arid rangeland of Ahmadun, Ziarat, Balochistanprovince of Pakistan. An area of 115 ha was protected from livestock grazing in April 2014. In June 2015, soil characteristics within 0-30 cm depth i.e. soil organic matter(SOM), mineral nitrogen, p H and texture in controlled and uncontrolled grazing sites were assessed. Aboveground vegetation biomass measured in early(June) and late summer(August) in 2015 and 2016. The nutritional value i.e. crude protein, phosphorus(P), neutral detergent fiber(NDF), acid detergent fiber(ADF), calcium(Ca), magnesium(Mg) and potassium(K) of dominantplant species were assessed at the beginning of experiment in 2015. Vegetation cover of controlled and uncontrolled grazing sites was also measured during the two years of the study period using the Veg Measure software. From June to November in2015 and 2016, controlled and uncontrolled livestock grazing sites were grazed on a daily basis by local ewes with a stocking rate of 2 and 1 head ha^(-1) respectively. Results reveal that the organic matter contents of coarse-textured, slightly alkaline soil of the study site were in the range of 9.4-17.6 g kg^(-1) soil and showed a strong positive correlation with aboveground vegetation biomass. The biomass of plants was 56.5% and 33% greater at controlled than uncontrolled grazing site in 2015 and 2016 respectively and plant cover was also higher at controlled than uncontrolled grazing site in both years The nutrient contents were significantly(P<0.05)lower in grasses than shrubs. In both years, the controlled grazing increased the weight gain of ewes about two folds compared to the uncontrolled grazing.The results indicate that controlled grazing improved the vegetation biomass production and small ruminant productivity. 展开更多
关键词 Grazing exclosure Soil organic matter Vegetation cover VegMeasure
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Influences of Soil Physical Properties on Water-Supplying Capacity 被引量:1
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作者 ZHAOBINGZI XUFUAN 《Pedosphere》 SCIE CAS CSCD 1997年第4期367-374,共8页
The water-supplying capacity of two agricultural soils, red soil in Jiangxi Province and meadow soil in Henan Province, was assessed mainly using physical investigations. The reticulated mottting horizon in the red so... The water-supplying capacity of two agricultural soils, red soil in Jiangxi Province and meadow soil in Henan Province, was assessed mainly using physical investigations. The reticulated mottting horizon in the red soil was a horizon limiting roots distribution due to its high density and hardness in structure and low pH (pH 5.05). The resistance of the red soil to drought hazard was poor because of its low water-supply capacity and poor hydraulic conductivity. The meadow soil had superior profile infiltration to that of the red soil and great available water-storage capacity) which resulted in low run-off loss, especially in the wheat-growth season. It was difficult for water stored in the deep layers of the meadow soil to reach the surface due to the low unsaturated hydraulic conductivity of its clay-rich horizon in subsoil. However, water stored in deep layers was still available because the roots could extend to the deep layers due to the relatively low density in soil structure. 展开更多
关键词 meadow soil red soil soil physical properties water-supplying capacity
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Composition and structure of species along altitude gradient in Moghan-Sabalan rangelands,Iran 被引量:1
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作者 Sahar GHAFARI Ardavan GHORBANI +2 位作者 Mehdi MOAMERI Raoof MOSTAFAZADEH Mahmood BIDARLORD 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1209-1228,共20页
This study provides a checklist of species distributed at the altitude gradient of MoghanSabalan rangelands in Ardabili province, Northwest Iran. We evaluated the changes in species composition, growth types of specie... This study provides a checklist of species distributed at the altitude gradient of MoghanSabalan rangelands in Ardabili province, Northwest Iran. We evaluated the changes in species composition, growth types of species, Raunkiaer's life forms, geographical distribution, threat and endemicity status, and palatability of species along two altitudinal gradients in the sampling plots, which were conducted in eleven sites/habitats with 300 meters above sea level(masl) altitude intervals(from 100 to 3300 masl). We assessed the plant species composition with special reference to the gradient analysis, and identified overall 396 species, which was comprising 44 families and 194 genera. Results showed that Asteraceae family is by far the most species-rich family, followed by Poaceae, Fabaceae, Caryophyllaceae and Brassicaceae. Among the genera, Astragalus is the most diverse genus, followed by Allium, Veronica and Bromus, Galium, Silene and Ranunculus. Results indicated that the number of species increased as the altitude increased to 1200-1500 masl, but then starts to decline to 3300 masl. Family-to-genera ratio was 1:4.4, the family-tospecies ratio was 1:9, and the genera-to-species ratio was 1:2.04. Growth type of species analysis shows that the frequency of perennial plants was higher in the study area followed by annual species while the lower group was biennial species. The number of annuals showed a decreasing trend towards higher altitude. Hemicryptophytes and therophytes were the most frequent life forms constituted each with(41.9%). Hemicryptophytes showed an increasing trend with altitude, while therophytes showed a decreasing trend with altitude increase, followed by geophytes, chamaephytes, and phanerophytes. Results showed more than half of the species of the study area belonged to Iran-Turanian region and these species showed an increasing trend with altitude. In contrast, Sahara-Sindian species comprise a minor component of the spectrum, with decreasing trend with altitude. The rare and endangered species out of the surveyed taxonomic groups comprised 53 species in total which 29 of them are considered lower risk(LR), 13 data deficient(DD), 5 vulnerable(Vu) and with 3 rare(R) and identified endemic plants comprised 24 species. Some 56.6% species were identified as class III, 22.6% were class I and 20.8% were class II as the palatability variation. Moghan-Sabalan rangelands require strong conservation management policies in case of species loss and changing natural communities due to the occurrence of conversion into cropland, over-grazing and other anthropogenic effects. 展开更多
关键词 FLORA Floristic diversity Speciesdistribution ELEVATION Red data categories ENDEMIC Ardabili province
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A preliminary discussion on the construction of marine ranching in Tianjin 被引量:1
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作者 FANG En-jun WANG Hong +1 位作者 WANG Shuo ZHANG Bo-lun 《Marine Science Bulletin》 CAS 2019年第1期1-15,共15页
Introduces the development connotation,development ideas,practice history and future prospects of Tianjin Ocean Ranch under the background of the development of national marine pastures.Combine the development process... Introduces the development connotation,development ideas,practice history and future prospects of Tianjin Ocean Ranch under the background of the development of national marine pastures.Combine the development process of China's marine pastures with the practice of Tianjin Ocean Ranch,the development characteristics of Tianjin marine pastures are analyzed.It is concluded that,for the future construction of Tianjin Ocean Ranch,we can focus on promoting the transformation of marine development mode to recycling,and construct a marine space development pattern of land-sea coordination and human-sea harmony,in order to accelerate the realization of Tianjin's"One Base and Three Districts"objective.We will make greater contributions to the quality of a well-off society and the creation of a beautiful new environment in Tianjin.Modern marine pastures are a long-term,complex and scientific systematic project that requires great attention and attention from all walks of life. 展开更多
关键词 marine pasture fishery resources ecological environment
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Decline of Traditional Landscape in a Protected Area of the Southwestern Alps:the Fate of Enclosed Pasture Patches in the Land Mosaic Shift 被引量:1
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作者 Matteo GARBARINO Emanuele SIBONA +1 位作者 Emanuele LINGUA Renzo MOTTA 《Journal of Mountain Science》 SCIE CSCD 2014年第2期544-554,共11页
【Title】【Author】【Addresses】1Traditional landscape elements such as pasture patches enclosed in a forest matrix are progressively disappearing throughout the European Alps. We assessed the land mosaic shift of a p... 【Title】【Author】【Addresses】1Traditional landscape elements such as pasture patches enclosed in a forest matrix are progressively disappearing throughout the European Alps. We assessed the land mosaic shift of a protected area located in the western Italian Alps. In particular, the dynamics of pasture patches were studied at both landscape and stand level. Land-cover mapping through object-oriented analysis of historical aerial photographs was used to assess land-cover changes between 1954 and 2000. Spatial statistics were used to quantify landscape patterns, and field samplings within pasture patches were used to explore tree regeneration structure and composition. Our results showed a significant increase in the number of pasture patches caused by their fragmentation following forest expansion. The total surface area of pasture patches decreased by 43% and their core area decreased by 94%. The encroachment of trees on less accessible areas of the pasture patches caused a reduction of patch shape at landscape scale. The gap filling process started 40-50 years ago and began with an early invasion of light demanding species like sycamore maple (Acer pseudoplatanus L.) and common ash (Fraxinus excelsior L.), followed by European beech (Fagus sylvatica L.) and secondarily silver fir (Abies alba Mill.). Traditional land-use and population decline in the Pesio Valley led to a reduction in ecotone areas. A transition to a more homogeneous landscape is expected in the next decades. Given the cultural and productive nature of these mountain meadow-pasture communities, extensive livestock grazing systems could be used to manage their future conservation. 展开更多
关键词 Landscape structure Secondary succession Historical ecology Pesio Valley Traditional land-use
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Ecological Consequences of Land Use Change: Forest Structure and Regeneration across the Forest-grassland Ecotone in Mountain Pastures in Nepal 被引量:1
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作者 Lila Nath SHARMA Ole Reidar VETAAS +1 位作者 Ram Prasad CHAUDHARY Inger Elisabeth MREN 《Journal of Mountain Science》 SCIE CSCD 2014年第4期838-849,共12页
The ecotone, the spatial transition zone between two vegetation communities, is claimed to have more species than the adjoining communities. However, empirical studies do not always confirm higher richness at the ecot... The ecotone, the spatial transition zone between two vegetation communities, is claimed to have more species than the adjoining communities. However, empirical studies do not always confirm higher richness at the ecotone. The ecotone position and structure are dynamic over time and space and it is driven by the changes in climate, land use or their interaction. In this context, we assessed the forest- grassland ecotone of temperate mountains in central Nepal by i) comparing species composition and richness across the ecotone, ii) analyzing if the forestgrassland ecotone is shifting towards the grassland center by colonizing them with trees, and iii) discussing the consequence of changed disturbance regime in the dynamics of this ecotone and the surrounding grasslands. We analyzed vegetation data sampled from belt transects laid across the forest- grassland ecotone in semi-natural grassland patches. Vegetation data consisting of species richness and composition, and size structure and regeneration of the two most dominant tree species, namely Rhododendron arboreum and Abies spectabilis, from the transects, were used to analyze the trend of the forest-grassland ecotone. Forest and grasslands were different in terms of floristic composition and diversity. Vascular plant speciesrichness linearly increased while moving from forest interior to grassland center. Spatial pattern of tree size structure and regeneration infers that forest boundary is advancing towards the grasslands at the expense of the grassland area, and tree establishment in the grasslands is part of a suceessional process. Temporally, tree establishment in grasslands started following the gradual decline in disturbance. We argue that local processes in terms of changed land use may best explain the phenomenon of ecotone shift and consequent forest expansion in these grasslands. We underpin the need for further research on the mechanism, rate and spatial extent of ecotone shift by using advaneed tools to understand the process indepth. 展开更多
关键词 Ecotone shift Grasslands Forest Landuse change RHODODENDRON
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