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REGULARITY AND ESTIMATION OF METHANE EMISSION FROM MARSHLAND IN THE SANJIANG PLAIN 被引量:1
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作者 崔保山 马学慧 张明祥 《Chinese Geographical Science》 SCIE CSCD 1998年第1期75-85,共0页
The regularity of CH 4 emission from marshland in the Sanjiang Plain was studied by sampling in the open field and analyzing under laboratory condition, the annual emission amount is also estimated. By Grey Relativel... The regularity of CH 4 emission from marshland in the Sanjiang Plain was studied by sampling in the open field and analyzing under laboratory condition, the annual emission amount is also estimated. By Grey Relatively Analysis we know that the soil temperature in the 10 cm depth of grass root layer is close related with CH 4 emission. CH 4 emission has different kinds of diurnal emission modes:before dawn maximum mode, night maximum mode and irregular fluctuation mode. The seasonal variation trend of CH 4 emission rates is going up steadily from May to August and dropping down from September,the maximum lies behind the maximum of temperature. CH 4 emission rates of different marshland types are different, the CH 4 emission rate of Glyceriaspiculosa-Carex marshland is always higher than that of Carex lasiocarpa marshland. The paper also studies the difference of CH 4 emission rates in different managing modes and analyzes the emission rates between China and U.S.A. The result shows: the average value of CH 4 emission rate is 17.26mg/(m 2·h),the annual amount of CH 4 emission is about 0.75Tg. 展开更多
关键词 Sanjiang PLAIN marshland METHANE EMISSION DIURNAL VARIATION seasonal VARIATION
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A Multi-Layer Based Assessment of Wetland Changes in the Southern Iraqi Marshlands Using Remotely Sensed Data 被引量:1
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作者 Felix Ike Chinyere Ruth Ottah 《International Journal of Geosciences》 2019年第9期801-810,共10页
Marshlands are important ecosystem for living organisms. The Southern Iraqi Marshland is the central habitat for freshwater fish, provides habitat for important populations of wildlife and serves as a source of income... Marshlands are important ecosystem for living organisms. The Southern Iraqi Marshland is the central habitat for freshwater fish, provides habitat for important populations of wildlife and serves as a source of income for native economies through reed harvesting. Studies have shown that variability in climate and human-induced factors affects the spatial dynamics of marsh ecosystems. This study assessed wetland changes in the Southern Iraqi Marshlands using Remotely Sensed Data from 1986 to 2019 using Landsat satellite imagery for four epochs: 1986, 2000, 2010 and 2019. To achieve this, thirty (30) pixels were obtained in selected land cover theme and their signatures were merged into one class. Furthermore, the selected pixels were recoded and merged into ten (10) land cover classes. The multi-layer classes created were shallow water, deep water, dense marsh, medium marsh, sparse marsh, dense vegetation, medium vegetation, sparse vegetation, dry soil and wet soil. The areal extents of the land cover types were calculated for 1986, 2000, 2010 and 2019. Normalized Difference Vegetation Index (NDVI) differencing was also carried in order to highlight trends in vegetation from 1986 to 2019. The study correlated historical trends of human activities as a central factor in the degradation of marshland (by 16.25%) from 1986 to 2000. However, by the year 2000 to 2010, there was an 11.36% increase in the total marshland area, which remained almost unchanged between 2010 and 2019. In 1986, NDVI was relatively stable at 0.73 in the Al-Hammar and Al-Hwaizeh Marsh. However, by 2000, the areas of dense vegetation cover reduced drastically by over 90%. In 2010, the NDVI index indicated trends of increasing water body and an outward cluster of healthier vegetation continuing to 2019. 展开更多
关键词 marshland NDVI Pixel REED HARVESTING
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Ten Years of Vegetation Change in Northern California Marshlands Detected Using Landsat Satellite Image Analysis
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作者 Christopher Potter 《Journal of Water Resource and Protection》 2013年第5期485-494,共10页
The Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) methodology was applied to detect changes in perennial vegetation cover at marshland sites in Northern California reported to have undergone restor... The Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) methodology was applied to detect changes in perennial vegetation cover at marshland sites in Northern California reported to have undergone restoration between 1999 and 2009. Results showed extensive contiguous areas of restored marshland plant cover at 10 of the 14 sites selected. Gains in either woody shrub cover and/or from a recovery of herbaceous cover that remains productive and evergreen on a year round basis could be mapped out from the image results. However, LEDAPS may not be highly sensitive changes in wetlands that have been restored mainly with seasonal herbaceous cover (e.g., vernal pools), due to the ephemeral nature of the plant greenness signal. Based on this evaluation, the LEDAPS methodology would be capable of fulfilling a pressing need for consistent, continual, low-cost monitoring of changes in marshland ecosystems of the Pacific Flyway. 展开更多
关键词 LANDSAT marshland VEGETATION WETLANDS Regrowth Restoration
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Mesopotamian Marshlands: Salinization Problem
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作者 Sama AlMaarofi Ali Douabul Hamid Al-Saad 《Journal of Environmental Protection》 2012年第10期1295-1301,共7页
Salinization becomes a very serious problem affecting the restoration assessment of the newly re-flooded marshes of the Mesopotamian southern Iraq. From mid-1970 to early-1990, the whole marsh area was influenced by w... Salinization becomes a very serious problem affecting the restoration assessment of the newly re-flooded marshes of the Mesopotamian southern Iraq. From mid-1970 to early-1990, the whole marsh area was influenced by water shortage and desiccation processes. Increasing the average salinity level in the re-flooded marshes is acting versus their recovery progress and significantly affecting their aquatic biota. This study will examine the contributions of dams’ construction and desiccation on increasing the salinity level with in the Mesopotamian marshlands overtime. Water discharge and salinity concentration were monitored in the direct water inputs and outlets of the three marshlands from May 2006 to February 2007 on a monthly basis, while salinity and major ions concentrations including “Ca1+, Mg2+, Cl1-, and SO42-” were monitored in 28 re-flooded marshes from March 2005 to August 2008 on a seasonal basis. The study indicate that increasing the salinity level in the Mesopotamian marshlands is due to three reasons: 1) The overtime increasing in the salinity level of their direct water inputs, due to dams’ constructions;2) the increase of the Arab Gulf tide via Shatt Al-Arab river due to the reduction of the water level in the outlets of the Central and Al-Hammar marshlands;and 3) the huge accumulation of salts due to desiccation. 展开更多
关键词 Mesopotamian marshlands Water SHORTAGE DESICCATION SALINIZATION MAJOR ION SOURCES
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Assessment of the Impact of Environment Protection in Rwanda:A Case Study of Rugezi Marshland
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作者 Ntabakirabose Gaspard Harold Ogwal +4 位作者 Jean Baptiste Habinshuti Musoni Protais Jeanne Pauline Munganyinka David Mwehia Mburu Maniriho Festus 《NASS Journal of Agricultural Sciences》 2022年第1期49-55,共7页
Environmental protection is one of the most important measures to achieve the long run and sustainability of living organisms in the world.The study was conducted in Burera and Gicumbi districts with the main aim of a... Environmental protection is one of the most important measures to achieve the long run and sustainability of living organisms in the world.The study was conducted in Burera and Gicumbi districts with the main aim of assessing the impact of environment protection in Rwanda.A case study of Rugezi Marchland.Data were collected using a structured questionnaire and analyzed using SPSS statistical software version 20 and STATA statistical software vision 13.Off-farm income,occupation,educational level,age,and farm size,showed a positive relationship with Rugezi marchland protection.Variables such as value of product distance to Rugezi marchland,gender,and family size had a negative influence on Rugezi marchland protection.The study also indicated that factors such as water management,increase of grass species,increase of wild animals and birds,modern house construction,zero grazing keeping revealing a positive relationship with Rugezi marchland protection.Two most serious problems encountered are the lack of occupation and low level of education. 展开更多
关键词 ASSESSMENT IMPACT Environment protection Rugezi marshland
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An integrated environmental improvement of marshlands:impact on control and elimination of schistosomiasis in marshland regions along the Yangtze River,China 被引量:8
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作者 Le-Ping Sun Wei Wang +6 位作者 Yin-Ping Zuo Zheng-Qiu Zhang Qing-Biao Hong Guo-Jing Yang Hong-Ru Zhu You-Sheng Liang Hai-Tao Yang 《Infectious Diseases of Poverty》 SCIE 2017年第1期624-633,共10页
Background:Schistosomiasis is a global snail-transmitted infectious disease of poverty.Transmission control had been achieved in China in 2015 after the control efforts for over 60 years.Currently,the remaining core r... Background:Schistosomiasis is a global snail-transmitted infectious disease of poverty.Transmission control had been achieved in China in 2015 after the control efforts for over 60 years.Currently,the remaining core regions endemic for Schistosoma japonicum are mainly located in the marshland and lake regions along the Yangtze River basin.Methods:During the period from 2001 through 2015,an integrated environmental improvement of the marshlands was carried out through the implementation of industrial,agricultural and resources development projects in Yizheng County along the Yangtze River.S.japonicum infection in humans,livestock and snails was estimated by serology,stool examination,hatching technique and microscopy during the 15-year study period to evaluate the effect of the integrated environmental improvement on control and elimination of schistosomiasis.Results:A 0.05%overall rate of S.japonicum infection was observed in snails during the 15-year study period,and no infected snails were detected since 2012.The overall prevalence of S.japonicum infection was 0.09%in humans during the study period,and no human infection was found since 2012.In addition,only 13 bovines were identified with S.japonicum infection in 2003 during the 15-year study period,and since 2004,no infection was found in livestock.Conclusion:The results of the present study demonstrate that the implementation of industrial,agricultural and water resources development projects,not only alters snail habitats in marshland regions,and promotes local economic development,which appears a win-to-win strategy to block the transmission of S.japonicum and accelerate socio-economic development along the Yangtze River. 展开更多
关键词 SCHISTOSOMIASIS Oncomelania hupensis Environmental improvement marshland regions Yangtze River basin China
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The spatiotemporal changes of marshland and the driving forces in the Sanjiang Plain, Northeast China from 1980 to 2016 被引量:4
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作者 Zhen Li Miao Liu +2 位作者 Yuanman Hu Zhenshan Xue Jinling Sui 《Ecological Processes》 SCIE EI 2020年第1期263-275,共13页
Background:Wetland loss is a global concern due to its enormous ecosystem services.Marshland,a typical natural wetland,which is concentrated in the Sanjiang Plain,has undergone dramatic loss in the last several decade... Background:Wetland loss is a global concern due to its enormous ecosystem services.Marshland,a typical natural wetland,which is concentrated in the Sanjiang Plain,has undergone dramatic loss in the last several decades.The spatiotemporal changes in marshland were studied based on Landsat images of the Sanjiang Plain from 1980 to 2016 with the land use maps in 1980,1995,2000,2005,2010,and 2016 using land use dynamic degree and landscape indices.The driving forces of marshland loss,including biophysical factors,socio-economic factors,and land management,were analyzed with boosted regression trees(BRTs)methods.Results:The area of marshland loss was 7372 km^(2),which accounted for 65.7%of the area of marshland in 1980;however,the paddy field area was expanded by 22,313 km^(2).The lost marshland was mainly converted to dry farmland(47.5%)and paddy field(47.2%)during 1980-2016.Both the landscape pattern of the study area and marshland became increasingly fragmented.The relatively important factors responsible for marshland loss were biophysical factors,socio-economic factors,and land management,which accounted for 65.2%,25.5%,and 8.4%,respectively.The most important driving forces with high“relative influence”were“distance to river,”which accounted for 20.6%of the total variance explained.The“relative influence”of potential crop yield and ditch density reached 20.2%and 8.4%,respectively.Conclusion:Significant land use changes have occurred in the Sanjiang Plain over the past 37 years,with characteristics of rapid paddy field expansion and drastic marshland loss.Meanwhile,marshland fragmentation continued to increase.Reclamation was the main reason for the large-scale marshland loss.Biophysical factors influenced the decisions regarding the locations of marshland loss.Moreover,climate factors(i.e.,average annual precipitation and average annual temperature)also played an important role in marshland loss.These results can provide helpful knowledge for understanding the patterns and reasons for marshland loss and protecting and managing strategies for wetlands restoration. 展开更多
关键词 Land use change marshland loss Driving forces The Sanjiang Plain
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雪山、草地与长征文化 被引量:1
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作者 王新生 《中国延安干部学院学报》 2023年第6期47-54,共8页
雪山、草地是红军长征途中所遇到最恶劣的自然环境。红军在翻雪山、过草地时,经历了最大的困难,付出了很大的牺牲。红军长征在雪山、草地期间形成的文件、诗词、歌曲、标语,一是集中体现了红军崇高的革命理想和信念,二是北上抗日是红军... 雪山、草地是红军长征途中所遇到最恶劣的自然环境。红军在翻雪山、过草地时,经历了最大的困难,付出了很大的牺牲。红军长征在雪山、草地期间形成的文件、诗词、歌曲、标语,一是集中体现了红军崇高的革命理想和信念,二是北上抗日是红军将士的普遍要求,三是宣传会师重要意义和团结一致的要求,四是宣传了各民族平等和共同革命。红军爬雪山、过草地期间创造了长征文化中最精彩的内容,对之进行宣传、展示,激励广大人民为实现第二个“一百年”的目标而努力奋斗,具有重要的现实意义。 展开更多
关键词 雪山 草地 长征文化
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长江流域安庆段植物多样性研究
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作者 方全 《安徽林业科技》 2023年第6期14-17,37,共5页
本文对长江安庆段植物群落进行了实地调查,以掌握该区域的植物资源现状,进而为长江生态环境保护提供数据支撑。结果表明,该区域维管植物共计70科207属325种,其中蕨类植物6科7属7种,裸子植物1科2属2种(均为栽培种),被子植物63科198属316... 本文对长江安庆段植物群落进行了实地调查,以掌握该区域的植物资源现状,进而为长江生态环境保护提供数据支撑。结果表明,该区域维管植物共计70科207属325种,其中蕨类植物6科7属7种,裸子植物1科2属2种(均为栽培种),被子植物63科198属316种;优势科为禾本科、菊科、莎草科。被子植物区系中,泛热带分布占比最高,为23.74%;其次为世界分布和北温带分布,占比分别为20.20%和19.19%;研究区植物属的区系以温带性质略占优势。该区域乔木层的平均蓄积量为103.24 m^(3)/hm^(2),18个代表性草本植物的平均生物量为1 648.36 g/m^(2)。 展开更多
关键词 长江滩涂 植物区系 生物量
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长江特大洪灾对江苏省江滩钉螺分布影响的研究 被引量:28
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作者 黄轶昕 戎国荣 +3 位作者 蔡刚 高智慧 周晓农 朱荫昌 《中国血吸虫病防治杂志》 CAS CSCD 2000年第6期346-349,共4页
目的 了解 1998年长江特大洪灾对江苏省江滩钉螺分布的影响。方法 对洪水淹没过的江滩采用系统抽样结合环境抽查的方法进行全面查螺。结果 长江洪灾后江苏省江滩钉螺面积较洪灾前净增加 1936 .45万 m2 ,阳性钉螺面积净增加 5 99.46万... 目的 了解 1998年长江特大洪灾对江苏省江滩钉螺分布的影响。方法 对洪水淹没过的江滩采用系统抽样结合环境抽查的方法进行全面查螺。结果 长江洪灾后江苏省江滩钉螺面积较洪灾前净增加 1936 .45万 m2 ,阳性钉螺面积净增加 5 99.46万 m2 。江滩钉螺主要分布在南京、扬州和镇江 3市 ,占全省江滩钉螺面积的 99.89% ,钉螺分布特点与 3个市江滩特殊的地理环境和冬陆夏水的生态条件有关 ,而洪水导致钉螺扩散是江滩钉螺面积增加的重要原因之一。结论  1998年长江特大洪灾对江苏省江滩钉螺的分布和扩散影响很大 。 展开更多
关键词 洪水 江滩 钉螺 扩散 血吸虫病 防治
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长江下游江滩地区血吸虫病再流行规律的研究 Ⅰ.钉螺的迁入与消长 被引量:27
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作者 孙乐平 周晓农 +6 位作者 洪青标 蔡刚 王裔林 黄轶昕 马玉才 吴锋 杨国静 《中国血吸虫病防治杂志》 CAS CSCD 2001年第4期213-215,共3页
目的 阐明长江下游地区钉螺再次迁入无螺江滩后的钉螺消长和分布变迁规律。方法 采用前瞻性观察的方法 ,每年春季现场调查钉螺分布。结果 每一滩块从局部有螺到全滩有螺平均时间为 4.33年 ,堤外江滩从钉螺迁入到全面有螺的时间需 8... 目的 阐明长江下游地区钉螺再次迁入无螺江滩后的钉螺消长和分布变迁规律。方法 采用前瞻性观察的方法 ,每年春季现场调查钉螺分布。结果 每一滩块从局部有螺到全滩有螺平均时间为 4.33年 ,堤外江滩从钉螺迁入到全面有螺的时间需 8年 ,试区从开始有螺到向堤内垦区扩散时间需 7年 ;10年间钉螺面积、钉螺平均密度、有螺框出现率分别增加了 74.97倍、90 .75倍和 10 6倍 ;有螺框出现率呈指数曲线 y=0 .1331e0 .5844 x上升 ;钉螺迁入早期以面积增长为主 ,在面积扩增到一定程度后 ,则转变为以螺口增长为主。结论 螺口数量的增加是钉螺扩散的基础 。 展开更多
关键词 江滩地区 钉螺 再流行 消长 扩散 血吸虫病
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湖滩地区血吸虫病流行因素与优化控制策略的研究 被引量:47
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作者 袁鸿昌 张绍基 +5 位作者 刘志德 姜庆五 杨求吉 胡林生 吴忠道 赵根明 《中国血吸虫病防治杂志》 CAS CSCD 1995年第4期193-201,共9页
本文报道了鄱阳湖区7个疫区村、13个单元人群血吸虫病再感染和疾病传播的规律,阐明了不同类型疫区中止化疗2年后疫情回升的动态,提出了4—6月间为湖区血吸虫在中间宿主—钉螺世代更替间的“交汇点”的新概念,提供了病牛为血吸虫病主要... 本文报道了鄱阳湖区7个疫区村、13个单元人群血吸虫病再感染和疾病传播的规律,阐明了不同类型疫区中止化疗2年后疫情回升的动态,提出了4—6月间为湖区血吸虫在中间宿主—钉螺世代更替间的“交汇点”的新概念,提供了病牛为血吸虫病主要传染源的新证据,重申了耕牛化疗在疾病控制中的重要地位;在对比不同防治策略费用—效果的基础上,创用了评价近,中、远期效果的“综合指数”,并据此提出了以易感地带为中心,开展灭螺和家畜化疗同步控制疾病传播的设想,以及近期湖区血防目标及其优化控制策略的模式。 展开更多
关键词 湖滩地区 血吸虫病 优化策略
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江滩型血吸虫病流行区江滩冲淤变化的定量研究 被引量:12
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作者 孙乐平 周晓农 +2 位作者 曹奇 洪青标 江仲熙 《中国血吸虫病防治杂志》 CAS CSCD 1998年第4期212-214,共3页
本研究采用测量陆地地形图的方法,对镇江市丹徒县世业洲16km江段进行了江滩冲淤变化景算。结果:1973年-1987年14年间,该江段累计冲刷江滩面积193.60万m2,淤涨江滩面积115.40万m2,净减少江滩面积67.90万m2。江岸滩以冲刷为主,... 本研究采用测量陆地地形图的方法,对镇江市丹徒县世业洲16km江段进行了江滩冲淤变化景算。结果:1973年-1987年14年间,该江段累计冲刷江滩面积193.60万m2,淤涨江滩面积115.40万m2,净减少江滩面积67.90万m2。江岸滩以冲刷为主,冲淤比为1:0.36;江心洲滩以淤积为主,冲淤比为1:1.27,且呈洲头冲刷,洲尾淤积态势。世业江心洲滩年均新增洲滩面积1.19万m2,占该洲1981年以来年均增加江滩钉螺面积的14.46%。揭示了两种类型江滩的冲淤数量关系,为长江中下游地区洲滩不断扩大,并不断有新洲滩形成提供了理论依据。 展开更多
关键词 江滩 冲刷 淤积 面积 血吸虫病 流行区
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藏北高原地面辐射收支的初步分析 被引量:56
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作者 马伟强 马耀明 +3 位作者 胡泽勇 李茂善 王介民 钱泽雨 《高原气象》 CSCD 北大核心 2004年第3期348-352,共5页
利用"全球能量与水循环亚洲季风之青藏高原试验"GAME/Tibet(GEWEXAsianMonsoonEx perimentintheTibetanPlateau)1998年加强期(IOP)观测资料,分析研究了藏北高原地区草甸下垫面在季风前、季风中、季风后的太阳短波向下辐射、... 利用"全球能量与水循环亚洲季风之青藏高原试验"GAME/Tibet(GEWEXAsianMonsoonEx perimentintheTibetanPlateau)1998年加强期(IOP)观测资料,分析研究了藏北高原地区草甸下垫面在季风前、季风中、季风后的太阳短波向下辐射、大气长波向下辐射、地面长波向上辐射、地面短波向上辐射、净辐射及地表反射率等特征,得到了藏北高原地区草甸下垫面辐射特征的新认识。 展开更多
关键词 藏北高原 草甸下垫面 地表辐射 夏季风
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藏北高原草甸下垫面近地层能量输送及微气象特征 被引量:100
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作者 马耀明 塚本修 +5 位作者 吴晓鸣 玉川一郎 王介民 石川裕彦 胡泽勇 高洪春 《大气科学》 CSCD 北大核心 2000年第5期715-722,共8页
利用 GAME/Tibet 1998年IOP观测资料,分析研究藏北高原草甸下垫面近地层的地面加热场、地表能量平衡、地面阻曳系数CD及感热通量整体输送系数CH等特征,得到了一些有关藏北高原草甸下垫面近地层能量输送及微气象... 利用 GAME/Tibet 1998年IOP观测资料,分析研究藏北高原草甸下垫面近地层的地面加热场、地表能量平衡、地面阻曳系数CD及感热通量整体输送系数CH等特征,得到了一些有关藏北高原草甸下垫面近地层能量输送及微气象特征结构的新认识。 展开更多
关键词 青藏高原 草甸下垫面 能量输送 微气象特征
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藏北高原典型草甸下垫面与HEIFE沙漠区辐射平衡气候学特征对比分析 被引量:41
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作者 钱泽雨 胡泽勇 +2 位作者 杜萍 马耀明 石川裕彦 《太阳能学报》 EI CAS CSCD 北大核心 2003年第4期453-460,共8页
利用中日合作"全球能量与水分平衡试验 青藏高原季风试验(GAME Tibet)"和中日合作"黑河地区地—气相互作用野外观测实验研究(HEIFE)"IOP、FOP资料,计算分析了藏北高原典型草甸下垫面安多站和HEIFE沙漠站的辐射平衡... 利用中日合作"全球能量与水分平衡试验 青藏高原季风试验(GAME Tibet)"和中日合作"黑河地区地—气相互作用野外观测实验研究(HEIFE)"IOP、FOP资料,计算分析了藏北高原典型草甸下垫面安多站和HEIFE沙漠站的辐射平衡各相关特征量时频变化的气候学特征。结果表明:无论是高原安多站还是黑河沙漠站,夏季均出现超太阳常数现象(只是安多更为明显);总辐射、大气逆辐射、地表长波辐射、地表有效辐射和地表辐射平衡等的日变化(晴天)无论是安多站还是沙漠站均表现为早晚出现最小值而正午附近(地方时)达到最大值,而地表反照率的日变化(晴天)相反表现为早晚大而正午附近小的规律;上述各分量均表现有程度不等的季节变化规律:总辐射、大气逆辐射、地表长波辐射和地表辐射平衡均表现为夏半年增大达到最大值百而冬半年降低量出现最小值;另外,大气长波辐射、地表有效辐射和地表反照率在沙漠站的年际变化的振幅较安多站更为显著和有规律。 展开更多
关键词 青藏高原 HEIFE 草甸下垫面 辐射平衡 气候学特征
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利用TM卫星遥感图像对鄱阳湖血吸虫病流行区水体识别的研究 被引量:14
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作者 姜庆五 刘建翔 +5 位作者 林涛 韦建国 赵根明 林丹丹 陈红根 张绍基 《中国公共卫生》 CAS CSCD 北大核心 2001年第4期289-290,共2页
方法 对鄱阳湖洪水季节和枯水季节的卫星TM图像进行图像合成和重新赋值。使水体与其它不同类别的地物明显区分 ,并对其面积进行计算。结果 在枯水季节计算机屏幕上的鄱阳湖的水体中共采集了 192 0 83个像元 ,其中 192 0 6 6个 (99 99... 方法 对鄱阳湖洪水季节和枯水季节的卫星TM图像进行图像合成和重新赋值。使水体与其它不同类别的地物明显区分 ,并对其面积进行计算。结果 在枯水季节计算机屏幕上的鄱阳湖的水体中共采集了 192 0 83个像元 ,其中 192 0 6 6个 (99 99%以上 )灰度值位于 2~ 5 9、11~ 11.9、38~ 41 9和45~ 45 .9间。而非鄱阳湖的其它水体采样 3 2 2 3个像元 ,其中2 948个 (91 5 % )位于以上灰度值内。枯水季节鄱阳湖区的水体面积约为鄱阳湖区的水体面积为 15 5 7 5 9km2 。洪水季节采集 86 5 6 8个像元 ,其中 86 35 1个 (99 75 % )灰度值位于 5~5 99、11~ 11 9、41~ 41 9和 47~ 47.9间。而非鄱阳湖的其它水体采样 780 6个像元 ,70 44个像元 (90 2 3% )位于以上灰度值内。 1998年洪水季节期间鄱阳湖区的水体面积为480 7 85km2 ,约为枯水季节的 3倍。重新赋值的形成的图像能将水体与周围的表面物体明显区别出来。结论 TM卫星遥感图像能作为与环境和水体有关卫星领域研究的工具。 展开更多
关键词 血吸虫病 遥感监测 湖沼地区 水体识别 TM卫星遥感图像
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江苏省江滩地区血吸虫病流行状况及防治效果的纵向观察 被引量:14
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作者 洪青标 黄轶昕 +6 位作者 周晓农 孙乐平 夏登华 徐国坤 田启安 朱济民 封喜成 《中国血吸虫病防治杂志》 CAS CSCD 2001年第3期132-136,共5页
目的 监测江苏省江滩地区血吸虫病的流行状况 ,评价防治效果。方法  1996~ 1999年在江苏省江滩地区设立 5个血吸虫病观察点 ,对螺情、病情等疫情指标以及防治措施进行纵向观察和监测分析。结果 疫情观察显示 ,江苏省江滩地区钉螺孳... 目的 监测江苏省江滩地区血吸虫病的流行状况 ,评价防治效果。方法  1996~ 1999年在江苏省江滩地区设立 5个血吸虫病观察点 ,对螺情、病情等疫情指标以及防治措施进行纵向观察和监测分析。结果 疫情观察显示 ,江苏省江滩地区钉螺孳生地面广量大 ,钉螺感染性较高。居民感染率较低 ,但耕牛感染率较高 ,仍为该地区的主要传染源。防治措施实施后 ,观察区内阳性钉螺面积和密度明显下降 ,但有螺面积下降幅度较小 ;居民感染率有较大幅度下降 ;耕牛感染率未明显下降。结论 江苏省江滩未控制地区血吸虫病疫情处于较高水平 ,且有进一步沿长江向下游蔓延趋势。目前的防治措施对维持居民感染率在较低水平是行之有效的 。 展开更多
关键词 江滩 血吸虫病 流行病学 纵向观察 防治
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江苏省沿江5市江滩滩情 螺情现状调查和钉螺控制策略的研究 被引量:33
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作者 黄轶昕 蔡刚 +5 位作者 吴锋 庞浩 宋鸿焘 张晓波 曹松林 朱荫昌 《中国血吸虫病防治杂志》 CAS CSCD 2000年第2期86-90,共5页
目的掌握江滩地区滩情特点和钉螺分布规律,探讨江滩地区钉螺控制的措施和策略。方法通过查阅资料和现场勘测,对江苏沿江5市江滩逐块调查滩情、螺情,并进行江滩开发治理可行性论证。结果共调查江滩607块,滩块面积16 243.... 目的掌握江滩地区滩情特点和钉螺分布规律,探讨江滩地区钉螺控制的措施和策略。方法通过查阅资料和现场勘测,对江苏沿江5市江滩逐块调查滩情、螺情,并进行江滩开发治理可行性论证。结果共调查江滩607块,滩块面积16 243.204 3万m~2,其中现有螺面积4 142.396 3万m~2,现有阳性钉螺面积 600. 8631万 m~2;现有螺江滩水淹时间均在 6个月内, 90. 88%现有螺滩块高程在3~9m间;调查表明江苏血吸虫病流行区江滩具有“冬陆夏水”特征,江滩有螺面积的增加与江滩面积增长及钉螺扩散有关;江滩有螺原因主要为上年未灭螺、灭而未净和钉螺扩散。目前可开发的滩块占尚未开发江滩面积的57.07%,如全部开发则可消灭现有江滩钉螺面积的47.16%。结论 基本掌握了江苏江滩地区滩情、螺情特点,探讨了江滩开发治理的可行性,提出了结合农业水利,采取以消除钉螺孳生条件为目标的生态工程方法控制江滩钉螺的防治策略。 展开更多
关键词 钉螺 江滩 控制策略 灭钉螺
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洞庭湖杨树林及原生湿地生态环境中鸟类的群落结构 被引量:17
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作者 邓学建 米小其 +3 位作者 牛艳东 周毅 任巍 李剑志 《农业现代化研究》 CSCD 北大核心 2008年第1期108-111,共4页
本文利用路线调查法对栽培速生杨的沅江江渚头垸和保持原始湿地环境的汉寿青山垸进行了鸟类资源调查。调查发现栽培杨树林后鸟类群落结构发生了改变,湿地鸟类物种数量减少,森林鸟类比例增加(达62%)。鸟类密度和多样性指数均有不同程度... 本文利用路线调查法对栽培速生杨的沅江江渚头垸和保持原始湿地环境的汉寿青山垸进行了鸟类资源调查。调查发现栽培杨树林后鸟类群落结构发生了改变,湿地鸟类物种数量减少,森林鸟类比例增加(达62%)。鸟类密度和多样性指数均有不同程度的降低。杨树林中鸟类群落结构单调,其中森林类型鸟类仅占洞庭湖区森林类型鸟类的24.1%. 展开更多
关键词 杨树林 湿地 鸟类 洞庭湖
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