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福州永泰高盖山“农家乐”旅游开发构想 被引量:1
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作者 贺伶俐 曾文田 袁书琪 《云南地理环境研究》 2009年第3期102-106,共5页
"农家乐"作为一种新兴旅游形式,在中国各地已如火如荼开展。"农家乐"旅游一般具有乡土味鲜明、平民性明显、原生美突出、参与性强的特点。因此,其持续、健康发展很大程度上取决于景区所提供的旅游产品。通过提出当... "农家乐"作为一种新兴旅游形式,在中国各地已如火如荼开展。"农家乐"旅游一般具有乡土味鲜明、平民性明显、原生美突出、参与性强的特点。因此,其持续、健康发展很大程度上取决于景区所提供的旅游产品。通过提出当前农家乐开发的一些问题,分析了永泰高盖山景区农家乐开发现状、可行性及外部环境与内部条件,最后提出符合高盖山具体情况的4种旅游产品即农业观光、田野人家、农事体验竞技及农业修学,同时提出开发原则。 展开更多
关键词 旅游开发 农家乐 高盖 永泰
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高盖山隧道4号缓坡长斜井井身快速钻爆施工技术 被引量:1
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作者 张有勇 刘旭全 《科技创新导报》 2011年第2期53-54,共2页
本文结合向莆铁路重点工程高盖山隧道4号斜井施工实践,对长大缓坡斜井硬岩快速钻爆施工技术进行总结,对类似工程施工具有很强的借鉴意义。
关键词 高盖山隧道 缓坡斜井 钻爆 快速施工
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新建向莆铁路高盖山隧道岩爆预测研究 被引量:3
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作者 陈大桂 《福建地质》 2010年第3期264-268,共5页
高盖山隧道岩爆预测采用工程岩体分级标准判别法、Russenes岩爆判别法、Turchaninov岩爆判别法和Hoek岩爆判别法等4种综合评定判别。当硬质脆性岩类隧道埋深小于240 m时,不会产生岩爆;埋深240-368 m时,可能产生轻微岩爆;埋深368-650 m... 高盖山隧道岩爆预测采用工程岩体分级标准判别法、Russenes岩爆判别法、Turchaninov岩爆判别法和Hoek岩爆判别法等4种综合评定判别。当硬质脆性岩类隧道埋深小于240 m时,不会产生岩爆;埋深240-368 m时,可能产生轻微岩爆;埋深368-650 m时,会发生中等规模岩爆;埋深大于650 m时会发生较强岩爆。 展开更多
关键词 地应力 岩爆 预测 向莆铁路 高盖
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福州南台高盖山及其妙峰寺考辨
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作者 郑淑榕 《福州大学学报(哲学社会科学版)》 2019年第4期104-109,共6页
位于福州市区南台岛中部盖山镇的高盖山,风景秀美,史迹丰富。山中妙峰寺,环境清幽,历史悠久。因为名称相同,地理位置相近,在涉及高盖山与妙峰寺的相关研究或游记中,常有学者文人将此山、寺误为福州市永泰县高盖山,或南台岛西北部的妙峰... 位于福州市区南台岛中部盖山镇的高盖山,风景秀美,史迹丰富。山中妙峰寺,环境清幽,历史悠久。因为名称相同,地理位置相近,在涉及高盖山与妙峰寺的相关研究或游记中,常有学者文人将此山、寺误为福州市永泰县高盖山,或南台岛西北部的妙峰寺。考辨南台高盖山,及其妙峰寺始末源流,厘清三地山、寺关系,关注本土文人在山、寺文化发展中的贡献,商兑正误,辨正歧见,应有助于高盖山文化研究的深入,亦有益于当下的高盖山生态公园建设。 展开更多
关键词 福州 南台 高盖 妙峰寺
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福州高盖山马尾松树轮宽度对气候变化的响应
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作者 赵鹏 《台湾农业探索》 2019年第6期76-82,共7页
【目的/意义】气候变化对农业生态系统有着重要的影响。通过研究福州高盖山马尾松树轮宽度对气候变化的响应,建立农业生态系统与气候变化研究模型,为研究气候变化对农业经济与农业生态系统提供科学经验。【方法/过程】以福州高盖山马尾... 【目的/意义】气候变化对农业生态系统有着重要的影响。通过研究福州高盖山马尾松树轮宽度对气候变化的响应,建立农业生态系统与气候变化研究模型,为研究气候变化对农业经济与农业生态系统提供科学经验。【方法/过程】以福州高盖山马尾松的树轮样本为研究对象,建立了马尾松树轮宽度年表,并分析了马尾松径向生长与气候因子的响应关系。【结果/结论】不同季节限制马尾松生长的气候因子不同,上年1-3月份的降水成为影响马尾松径向生长的主要因子,树轮宽度与上年1-3月降水量呈显著负相关(r=-0.347);当年7-9月份温度成为影响马尾松径向生长的主要因子,树轮宽度指数与当年7-9月温度呈显著正相关(r=0.379)。研究表明,一年中不同时期限制马尾松径向生长的气候因子不同,说明亚热带湿润地区的树木径向生长也对气候的变化有一定的响应作用。 展开更多
关键词 福州高盖 马尾松 树轮宽度 气候变化
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高盖文林双峰碧
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作者 施晓宇 《闽都文化》 2019年第3期68-72,共5页
一福建省简称闽,亦称左海。故而福建省会福州市简称榕,亦称左海福地。左海'谓海居于东'。明万历四十一年(1613),《福州府志》记载了一条流传到今天的民谚:'三山藏,三山现,三山看不见。'其中的'三山现',说的就... 一福建省简称闽,亦称左海。故而福建省会福州市简称榕,亦称左海福地。左海'谓海居于东'。明万历四十一年(1613),《福州府志》记载了一条流传到今天的民谚:'三山藏,三山现,三山看不见。'其中的'三山现',说的就是于山、乌山、屏山,三山鼎立,一直是福州的地标。 展开更多
关键词 妙峰寺 福州市 高盖 海灯法师 清定法师 考古略
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近红外光谱技术快速测定农药有效成分的研究 被引量:10
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作者 熊艳梅 段云青 +2 位作者 王冬 段佳 闵顺耕 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2010年第6期1488-1492,共5页
农药有效成分含量不足和农药有效成分滥用是农药质量不合格的最主要问题,但是缺乏农药的快速现场分析方法。采用傅里叶近红外光谱技术结合偏最小二乘法(PLS),定量分析了乳油中有效成分高盖的含量,模型的决定系数R2大于0.9999,SEC小于0.0... 农药有效成分含量不足和农药有效成分滥用是农药质量不合格的最主要问题,但是缺乏农药的快速现场分析方法。采用傅里叶近红外光谱技术结合偏最小二乘法(PLS),定量分析了乳油中有效成分高盖的含量,模型的决定系数R2大于0.9999,SEC小于0.019,SEP小于0.030;同时对影响模型的因素进行了研究,并用实际样品进行了验证。结果表明:近红外光谱技术可以准确地定量分析农药乳油中有效成分含量,仪器分辨率、助剂含量变化对模型的影响不显著。近红外光谱法测量商品农药制剂中有效成分的含量,方便快速,特别适合现场、在线分析,对生产企业的连续在线检测、监督部门进行农药质量控制和农产品安全具有重要意义。 展开更多
关键词 近红外光谱 农药 偏最小二乘法 现场分析 高盖
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李白《送友人》之“友人”事迹考 被引量:2
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作者 曾明 《社会科学研究》 CSSCI 北大核心 2009年第4期173-177,共5页
李白名诗《送友人》之"友人"为谁,学界至今不得其解。从种种资料来看,"友人"实为范崇凯。范崇凯是唐玄宗开元四年状元,后应诏作《花萼楼赋》,为天下第一。李白此诗,盖是他15岁时在蜀中送别范崇凯赴长安赶考前之作... 李白名诗《送友人》之"友人"为谁,学界至今不得其解。从种种资料来看,"友人"实为范崇凯。范崇凯是唐玄宗开元四年状元,后应诏作《花萼楼赋》,为天下第一。李白此诗,盖是他15岁时在蜀中送别范崇凯赴长安赶考前之作。同时需要指出的是:今传范崇凯所作的《花萼楼赋》并《序》,并非范氏所为,而是高盖之作。 展开更多
关键词 李白 《送友人》 《花萼楼赋》 范崇凯 高盖
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Accurate Quantification of Grassland Cover Density in an Alpine Meadow Soil Based on Remote Sensing and GPS 被引量:12
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作者 LIU Yan-Sui HU Ye-Cui PENG Liu-Ying 《Pedosphere》 SCIE CAS CSCD 2005年第6期778-783,共6页
The principles of remotely estimating grassland cover density in an alpine meadow soil from space lie in the synchronous collection of in situ samples with the satellite pass and statistically linking these cover dens... The principles of remotely estimating grassland cover density in an alpine meadow soil from space lie in the synchronous collection of in situ samples with the satellite pass and statistically linking these cover densities to their image properties according to their geographic coordinates. The principles and procedures for quantifying grassland cover density from satellite image data were presented with an example from Qinghai Lake, China demonstrating how quantification could be made more accurate through the integrated use of remote sensing and global positioning systems (GPS). An empirical model was applied to an entire satellite image to convert pixel values into ground cover density. Satellite data based on 68 field samples was used to produce a map of ten cover densities. After calibration a strong linear regression relationship (r2 = 0.745) between pixel values on the satellite image and in situ measured grassland cover density was established with an 89% accuracy level. However, to minimize positional uncertainty of field samples, integrated use of hyperspatial satellite data and GPS could be utilized. This integration could reduce disparity in ground and space sampling intervals, and improve future quantification accuracy even more. 展开更多
关键词 alpine meadow soil grassland cover density quantitative remote sensing Qinghai Lake
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Classification of plant functional types based on the nutrition traits: a case study on alpine meadow community in the Zoigê Plateau 被引量:6
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作者 SHEN Song-tao ZHANG Shu-jie +1 位作者 FAN Min WANG Qing 《Journal of Mountain Science》 SCIE CSCD 2017年第10期2003-2012,共10页
The ecological concept of Plant Functional Types(PFTs), which refers to the assemblage of plants with certain functional traits, has been introduced for the study of plant responses to the environment change and hum... The ecological concept of Plant Functional Types(PFTs), which refers to the assemblage of plants with certain functional traits, has been introduced for the study of plant responses to the environment change and human disturbance. Taking the alpine meadow community in the Zoigê Plateau as a study case, this paper classified PFTs in terms of plant nutrition traits. The sequential results are as follows.(1) The main herbages in the Zoigê Plateau included 16 species in 5 families. Among the five families, Cyperaceae vegetation accounted for 81.37%of herbage area in total, while the remaining 4families occupied less than 20%. As for the species,Kobresia setchwanensis Hand.-Maizz. was dominant,accounting for 48.74% of the total area; while the remaining 51.26% was comprised of Polygonum viviparum L., Anaphalis fiavescens Hand.-Mazz.,Stipa aliena Keng and other species.(2) By using the Principal Component Analysis(PCA), the assessment of herbages nutrition was carried out based on the comprehensive multi-index evaluation model.Polygonum viviparum L. had the highest nutritional value score(1.43), and Stipa aliena Keng had the lowest(-1.40). Nutritional value of herbage species had a significantly positive correlation with altitude(P&lt;0.01) in the Zoigê Plateau.(3) Based on the nutritional values, herbages in the Zoigê Plateau could be grouped into 3 nutrition PFTs(high, medium and low) by using the Natural Breaks(Jenks) method. 展开更多
关键词 Plant functional types Nutritional value Forage resource management the Zoigê Plateau
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Soil Cellulase Activity and Fungal Community Responses to Wetland Degradation in the Zoige Plateau, China 被引量:8
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作者 WU Li-sha FENG Su +3 位作者 NIE Yuan-yang ZHOU Jian-hong YANG Zhi-rong ZHANG Jie 《Journal of Mountain Science》 SCIE CSCD 2015年第2期471-482,共12页
Four soil types(peat, marsh, meadow, and sandy) in the Zoige Plateau of China are associated with the severity of wetland degradation. The effects of wetland degradation on the structure and abundance of fungal commun... Four soil types(peat, marsh, meadow, and sandy) in the Zoige Plateau of China are associated with the severity of wetland degradation. The effects of wetland degradation on the structure and abundance of fungal communities and cellulase activity were assessed in these 4 soil types at 3 depths using DGGE(Denatured Gradient Gel Electrophoresis), q PCR(Quantitative Real-time PCR),and 3,5-dinitrosalicylic acid assays. Cellulase activity and abundance of the fungal community declined in parallel to the level of wetland degradation(from least to most disturbed). DGGE analysis indicated a major shift in composition of fungal communities among the4 soil types consistent with the level of degradation.Water content(WC), organic carbon(OC), total nitrogen(TN), total phosphorus(TP), available nitrogen(AN), and available phosphorus(AP) were strongly correlated with cellulase activity and the structure and abundance of the fungal community.The results indicate that soil physicochemical properties(WC, OC, TN, TP, AN, and AP), cellulase activity, and diversity and abundance of fungal communities are sensitive indicators of the relative level of wetland degradation. WC was the major factorinvolved in Zoige wetland degradation and lower WC levels contributed to declines in the abundance and diversity of the fungal community and reduction in cellulase activity. 展开更多
关键词 Wetland degradation Soil cellulase Fungal community DGGE(Denatured Gradient Gel Electrophoresis) qPCR(Quantitative Real-time PCR)
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Persistence of Snow Cover Anomalies over the Tibetan Plateau and the Implications for Forecasting Summer Precipitation over the Meiyu-Baiu Region 被引量:7
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作者 LIU Ge WU Ren-Guang ZHANG Yuan-Zhi 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第2期115-119,共5页
The present reported study investigated the persistence of snow anomalies over the Tibetan Plateau(TP) from the preceding seasons to summer and the relationship between the previous snow cover anomaly and summer preci... The present reported study investigated the persistence of snow anomalies over the Tibetan Plateau(TP) from the preceding seasons to summer and the relationship between the previous snow cover anomaly and summer precipitation over East Asia. The results showed that, relative to other snow indices, such as the station observational snow depth(SOSD) index and the snow water equivalent(SWE) index, the snow cover area proportion(SCAP) index calculated from the SWE and the percentage of visible snow of the Equal-Area Scalable Earth Grids(EASE-grids) dataset has a higher persistence in interannual anomalies, particularly from May to summer. As such, the May SCAP index is significantly related to summer precipitation over the Meiyu-Baiu region. The persistence of the SCAP index can partly explain the season-delayed effect of snow cover over the TP on summer rainfall over the Meiyu-Baiu region besides the contribution of the soil moisture bridge. The preceding SST anomaly in the tropical Indian Ocean and ENSO can persist through the summer and affect the summer precipitation over the Meiyu-Baiu region. However, the May SCAP index is mostly independent of the simultaneous SSTs in the tropical Indian Ocean and the preceding ENSO and may affect the summer precipitation over the Meiyu-Baiu region independent of the effects of the SST anomalies. Therefore, the May SCAP over the TP could be regarded as an important supplementary factor in the forecasting of summer precipitation over the Meiyu-Baiu region. 展开更多
关键词 snow cover Tibetan Plateau MEIYU precipitation forecast
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A Method for Alpine Wetland Delineation and Features of Border: Zoigê Plateau, China 被引量:2
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作者 ZHENG Yaomin NIU Zhenguo +12 位作者 GONG Peng LI Mengna HU Lile WANG Lei YANG Yuxiang GU Hai-jun MU Jinrong DOU Gejia XUE Hui WANG Lin LI Hua DOU Gejie DANG Zhicairang 《Chinese Geographical Science》 SCIE CSCD 2017年第5期784-799,共16页
Accurate wetland delineation is the basis of wetland definition and mapping, and is of great importance for wetland management and research. The Zoige Plateau on the Qinghai-Tibet Plateau was used as a research site f... Accurate wetland delineation is the basis of wetland definition and mapping, and is of great importance for wetland management and research. The Zoige Plateau on the Qinghai-Tibet Plateau was used as a research site for research on alpine wetland delineation. Several studies have analyzed the spatiotemporal pattern and dynamics of these alpine wetlands, but none have addressed the issues of wetland boundaries. The objective of this work was to discriminate the upper boundaries of alpine wetlands by coupling ecological methods and satellite observations. The combination of Landsat 8 images and supervised classification was an effective method for rapid identification of alpine wetlands in the Zoig6 Plateau. Wet meadow was relatively stable compared with hydric soils and wetland hydrology and could be used as a primary indicator for discriminating the upper boundaries of alpine wetlands. A slope of less than 4.5° could be used as the threshold value for wetland delineation. The normalized difference vegetation index (NDVI) in 434 field sites showed that a threshold value of 0.3 could distinguish grasslands from emergent marsh and wet meadow in September. The median normalized difference water index (NDWI) of emergent marsh remained more stable than that of wet meadow and grasslands during the period from September until July of the following year. The index of mean density in wet meadow zones was higher than the emergent and upland zones. Over twice the number of species occurred in the wet meadow zone compared with the emergent zone, and close to the value of upland zone. Alpine wetlands in the three reserves in 2014 covered 1175.19 kin2 with a classification accuracy of 75.6%. The combination of ecological methods and remote sensing technology will play an important role in wetland delineation at medium and small scales. The correct differentiation between wet meadow and grasslands is the key to improving the accuracy of future wetland delineation. 展开更多
关键词 alpine wetland delineation ecological methods remote sensing Zoige Plateau
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Landscape Pattern Evolution Processes of Alpine Wetlands and Their Driving Factors in the Zoige Plateau of China 被引量:30
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作者 BAI Jun-hong LU Qiong-qiong +4 位作者 WANG Jun-jing ZHAO Qing-qing OUYANG Hua DENG Wei LI Ai-nong 《Journal of Mountain Science》 SCIE CSCD 2013年第1期54-67,共14页
Zoige Plateau wetlands are located in the northeastern corner of the Qinghai-Tibet Plateau.The landscape pattern evolution processes in the Zoige Plateau and their driving factors were identified by analyzing the dyna... Zoige Plateau wetlands are located in the northeastern corner of the Qinghai-Tibet Plateau.The landscape pattern evolution processes in the Zoige Plateau and their driving factors were identified by analyzing the dynamic changes in landscape modification and conversion and their dynamic rates of alpine wetlands over the past four decades.The results showed that the landscape conversion between wetlands and non-wetlands mainly occurred during the period from 1966 to 1986.The marsh wetland area converted from lake and river wetlands was larger because of swamping compared to other wetland landscapes.Meanwhile,the larger area of marsh wetlands was also converted to lake wetlands more than other types of wetlands.The modification processes mainly occurred among natural wetland landscapes in the first three periods.Obvious conversions were observed between wetland and nonwetland landscapes(i.e.,forestland,grassland,and other landscapes) in the Zoige Plateau.These natural wetland landscapes such as river,lake and marsh wetlands showed a net loss over the past four decades,whereas artificial wetland landscapes(i.e.,paddy field and reservoir and pond wetlands) showed a net decrease.The annual dynamic rate of the whole wetland landscape was 0.72%,in which the annual dynamic rate of river wetlands was the highest,followed by lake wetlands,while marsh wetlands had the lowest dynamic rate.The integrated landscape dynamic rate showed a decreasing trend in the first three periods.The changes in wetland landscape patterns were comprehensively controlled by natural factors and human activities,especially human activities play an important role in changing wetland landscape patterns. 展开更多
关键词 Zoige Plateau Alpine wetland Landscape pattern Modification Conversion Driving factors
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Sensitivity analysis of the De Nitrification and De Composition model for simulating regional carbon budget at the wetlandgrassland area on the Zoige Plateau,China 被引量:3
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作者 WANG Ji-yan LI Ai-nong JIN Hua-an 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1200-1216,共17页
Although mathematical models(e.g., De Nitrification and De Composition(DNDC) provide a powerful tool to study regional carbon budget, it is still difficult to obtain accurate simulation results because there exists la... Although mathematical models(e.g., De Nitrification and De Composition(DNDC) provide a powerful tool to study regional carbon budget, it is still difficult to obtain accurate simulation results because there exists large uncertainties in modeling regional carbon budget. Through the investigation on the sensitivity of model output parameters to the input parameters, sensitivity analysis(SA) has been proved to be able to identify the key sources of uncertainties and be helpful to reduce the model uncertainties. However, some input parameters with discrete values(e.g., land use type and soil type) and the regional effect of the sensitive parameters were rarely examined in SA. In this paper, taking the Zoige Plateau as a case area, we combined the one-factor-ata-time(OAT) with Extended Fourier Amplitude Sensitivity Test(EFAST) to conduct a SA of DNDC for simulating the regional carbon budget, including Gross Primary Productivity(GPP), Net Primary Productivity(NPP), Net Ecosystem Productivity(NEP), autotrophic respiration(Ra), soil microbial heterotrophic respiration(Rh) and ecosystem respiration(Re). The result showed that the combination of OAT and EFAST could test the contribution of the input parameters with discrete values to the output parameters. In DNDC model, land use type and soil type had a significant impact on the regional carbon budget of the Zoige Plateau, and daily temperature was also confirmed to be one of the most important parameters for carbon budget. For the other input parameters, with the change of land use type or soil type at regional scale, the sensitive parameters of carbon budget would vary accordingly. The SA results would provide scientific evidence to optimize DNDC model and they suggested that we should pay attention to the spatial/temporal effect of SA and try to use the appropriate data in simulation of the regional carbon budget. 展开更多
关键词 Sensitivity analysis OAT EFAST DNDC model Carbon budget Zoige Plateau
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Responses of soil inhabiting nitrogen-cycling microbial communities to wetland degradation on the Zoige Plateau,China 被引量:3
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作者 WU Li-sha NIE Yuan-yang +1 位作者 YANG Zhi-rong ZHANG Jie 《Journal of Mountain Science》 SCIE CSCD 2016年第12期2192-2204,共13页
The wetlands on the Zoige Plateau have experienced serious degradation,with most of the original marsh being converted to marsh meadow or meadow.Based on the 3 wetland degradation stages,we determined the effects of w... The wetlands on the Zoige Plateau have experienced serious degradation,with most of the original marsh being converted to marsh meadow or meadow.Based on the 3 wetland degradation stages,we determined the effects of wetland degradation on the structure and relative abundance of nitrogencycling(nitrogen-fixing,ammonia-oxidizing,and denitrifying) microbial communities in 3 soil types(intact wetland:marsh soil;early degrading wetland:marsh meadow soil;and degraded wetland:meadow soil) using 454-pyrosequencing.The structure and relative abundance of nitrogen-cycling microbial communities differed in the 3 soil types.Proteobacteria was the predominant phylum in most soil samples but the most abundant soil nitrogenfixing and denitrifying microbial bacteria differed at the class,order,family,and genus levels among the 3soil types.At the genus level,the majority of nitrogenfixing bacterium sequences related to Bradyrhizobium were from marsh and marsh meadow soils;whereas those related to Geobacter originated from meadow soil.The majority of ammonia-oxidizing bacterium sequences related to Nitrosospira were from marsh(except for the 40-60 cm layer),marsh meadow and meadow soils;whereas those related to Candidatus Solibacter originated from 40-60 cm layer of marsh soil.The majority of denitrifying bacterium sequences related to Candidatus Solibacter and Anaeromyxobacter were from marsh and meadow soils;whereas those related to Herbaspirillum originated from meadow soil.The distribution of operational taxonomic units(OTUs)and species were correlated with soil type based upon Venn and Principal Coordinates Analysis(PCoA).Changes in soil type,caused by different water regimes were the most important factors influencing compositional changes in the nitrogen-fixing,ammonia-oxidizing,and denitrifying microbial communities. 展开更多
关键词 Zoige Plateau Wetland degradation Nitrogen-cycling microbial communities 454 Pyrosequencing
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High-Temperature Corrosion of Protective Coatings for Boiler Tubes in Thermal Power Plants 被引量:2
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作者 徐连勇 荆洪阳 霍立兴 《Transactions of Tianjin University》 EI CAS 2005年第3期183-189,共7页
High-temperature corrosion is a serious problem for the water-wall tubes of boilers used in thermal power plants. Oxidation, sulfidation and molten salt corrosion are main corrosion ways.Thereinto, the most severe cor... High-temperature corrosion is a serious problem for the water-wall tubes of boilers used in thermal power plants. Oxidation, sulfidation and molten salt corrosion are main corrosion ways.Thereinto, the most severe corrosion occurs in molten salt corrosion environment. Materials rich in oxides formers, such as chromium and aluminum, are needed to resist corrosion in high-temperature and corrosive environment, but processability of such bulk alloys is very limited. High velocity electric arc spraying (HVAS) technology is adopted to produce coatings with high corrosion resistance. By comparison, NiCr (Ni-45Cr-4Ti) is recommended as a promising alloy coating for the water-wall tubes, which can even resist molten salt corrosion attack. In the study of corrosion mechanism, the modern material analysis methods, such as scanning electron microscopy (SEM), X-ray diffractometry (XRD) and energy dispersive spectrometry (EDS), are used. It is found that the corrosion resistances of NiCr and FeCrAI coatings are much better than that of 20g steel, that the NiCr coatings have the best anti-corrosion properties, and that the NiCr coatings have slightly lower pores than FeCrAI coatings.It is testified that corrosion resistance of coatings is mainly determined by chromium content, and the microstructure of a coating is as important as the chemical composition of the material. In addition, the fracture mechanisms of coatings in the cycle of heating and cooling are put forward. The difference of the thermal physical properties between coatings and base metals results in the thermal stress inside the coatings. Consequently, the coatings spall from the base metal. 展开更多
关键词 high-temperature corrosion high velocity electric arc spraying (HVAS) COATING boiler tubes thermal shock test
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LAND-COVER DENSITY-BASED APPROACH TO URBAN LAND USE MAPPING USING HIGH-RESOLUTION IMAGERY 被引量:1
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作者 ZHANGXiu-ying FENGXue-zhi 《Chinese Geographical Science》 SCIE CSCD 2005年第2期162-167,共6页
Nowadays, remote sensing imagery, especially with its high spatialresolution, has become an indispensable tool to provide timely up-gradation of urban land use andland cover information, which is a prerequisite for pr... Nowadays, remote sensing imagery, especially with its high spatialresolution, has become an indispensable tool to provide timely up-gradation of urban land use andland cover information, which is a prerequisite for proper urban planning and management. Thepossible method described in the present paper to obtain urban land use types is based on theprinciple that land use can be derived from the land cover existing in a neighborhood. Here, movingwindow is used to represent the spatial pattern of land cover within a neighborhood and seven windowsizes (61mx61m, 68mx68m, 75mx75m, 87mx87m, 99mx99m, 110mx110m and 121mxl21m) are applied todetermining the most proper window size. Then, the unsupervised method of ISODATA is employed toclassify the layered land cover density maps obtained by the moving window. The results of accuracyevaluation show that the window size of 99mx99m is proper to infer urban land use categories and theproposed method has produced a land use map with a total accuracy of 85%. 展开更多
关键词 urban land use land cover density map high-resolution image
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Quantifying land degradation in the Zoige Basin,NE Tibetan Plateau using satellite remote sensing data 被引量:12
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作者 YU Kai-feng Frank LEHMKUHL Dimitri FALK 《Journal of Mountain Science》 SCIE CSCD 2017年第1期77-93,共17页
Considerable efforts have been dedicated to desertification research in the arid and semi-arid drylands of central Asia. However,there are few quantitative studies in conjunction with proper qualitative evaluation con... Considerable efforts have been dedicated to desertification research in the arid and semi-arid drylands of central Asia. However,there are few quantitative studies in conjunction with proper qualitative evaluation concerning land degradation and aeolian activity in the alpine realm. In this study,spectral information from two Landsat-5 TM scenes(04.08.1994 and 28.07.2009,respectively) was combined with reference information obtained in the field to run supervised classifications of eight landscape types for both time steps. Subsequently,the temporal and spatial patterns of the alpine wetlands/grasslands evolutions in the Zoige Basin were quantified and assessed based on these two classification maps. The most conspicuous change is the sharp increase of ~627 km^2 degraded meadow. Concerning other land-covers,shallow wetland increases ~107 km^2 and aeolian sediments(mobile dunes and sand sheets) have an increase of ~30 km^2. Considering the deterioration,an obvious decrease of ~440 km^2 degraded wetland can be observed. Likewise,decrease of deep wetland(~78 km^2),humid meadow(~80 km^2) and undisturbed meadow(~88 km^2) were determined. These entire evolution matrixes undoubtedly hint a deteriorating tendency of the Zoige Basin ecosystem,which is characterized by significantly declined proportion of intact wetlands,meadow,rangeland and a considerable increase ofdegraded meadow and larger areas of mobile dunes. In particular,not only temporal alteration of the landcover categories,the spatial and topographical characteristics of the land degradation also deserves more attention. In the alpine rangelands,the higher terraces of the river channels along with their slopes are more liable to the degradation and desertification. This tendency has significantly impeded the nomadic and agriculture activities. The set of anthropozoogenic factors encompassing enclosures,overgrazing and trampling,rodent damaging and exceedingly ditching in the wetlands are assumed to be the main controlling mechanisms for the landscape degradation. A suite of strict protection policies is urgent and indispensable for self-regulation and restoration of the alpine meadow ecosystem. Controlling the size of livestock,less ditching in the rangeland,and the launching of a more strict nature reserve management by adjacent Ruoergai,Maqu and Hongyuan Counties would be practical and efficacious in achieving these objectives. 展开更多
关键词 Alpine ecosystem Wetlands Degradation Desertification Zoige Basin Driving mechanisms
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Effects of Temperature,Soil Moisture,Soil Type and Their Interactions on Soil Carbon Mineralization in Zoigê Alpine Wetland,Qinghai-Tibet Plateau 被引量:25
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作者 GAO Junqin OUYANG Hua +2 位作者 LEI Guangchun XU Xingliang ZHANG Mingxiang 《Chinese Geographical Science》 SCIE CSCD 2011年第1期27-35,共9页
Wetland stores substantial amount of carbon and may contribute greatly to global climate change debate. However, few researches have focused on the effects of global climate change on carbon mineralization in Zoige al... Wetland stores substantial amount of carbon and may contribute greatly to global climate change debate. However, few researches have focused on the effects of global climate change on carbon mineralization in Zoige alpine wetland, Qinghai-Tibet Plateau, which is one of the most important peatlands in China. Through incubation experiment, this paper studied the effects of temperature, soil moisture, soil type (marsh soil and peat soil) and their interactions on CO2 and CH4 emission rates in Zoige alpine wetland. Results show that when the temperature rises from 5℃ to 35℃, CO2 emission rates increase by 3.3-3.7 times and 2.4-2.6 times under non-inundation treatment, and by 2.2-2.3 times and 4.1-4.3 times under inundation treatment in marsh soil and peat soil, respectively. Compared with non-inundation treatment, CO2 emission rates decrease by 6%-44%, 20%-60% in marsh soil and peat soil, respectively, under inundation treatment. CO2 emission rate is significantly affected by the combined effects of the temperature and soil type (p 〈 0.001), and soil moisture and soil type (p 〈 0.001), and CH4 emission rate was significantly affected by the interaction of the temperature and soil moisture (p 〈 0.001). Q10 values for CO2 emission rate are higher at the range of 5 ℃-25℃ than 25 ℃-35℃, indicating that carbon mineralization is more sensitive at low temperature in Zoige alpine wetland. 展开更多
关键词 alpine wetland carbon mineralization marsh soil peat soil soil moisture Qinghai-Tibet Plateau
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