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1.
高寒区植被变化一直是气候和生态学领域关注的热点问题。本研究基于MODIS NDVI数据计算的植被覆盖度数据和高分辨率气象数据,分析了青海湖流域2001-2017年植被覆盖度分布格局及动态变化,探讨了其对气候变化、人类活动和冻土退化的响应。结果表明:① 近十几年青海湖流域植被覆盖度整体表现为增加趋势,不同植被类型增幅存在差异性,草地增幅最大,达到6.1%/10a,其它植被类型增幅在2%~3%/10a之间;② 流域局部地区仍存在植被退化现象,研究期植被退化面积表现为先增加后减小的变化趋势。2006-2011年重度退化区集中在青海湖东岸,2011-2017年重度退化区集中在流域的西北部,这些区域是青海湖流域荒漠分布区,植被覆盖度较低,是今后生态恢复需重点关注的区域;③ 气候变化是流域植被覆盖度变化的主导因素,气候变化对青海湖流域主要植被类型覆盖度变化的贡献率为84.21%,对草原、草甸和灌丛植被覆盖度变化的贡献率分别为81.84%、87.47%和75.96%;④ 人类活动对流域主要植被类型覆盖度变化的贡献率为15.79%,对草原、草甸和灌丛植被覆盖度变化的贡献率分别为18.16%、12.53%和24.04%,环青海湖地区人类活动对植被恢复有促进效应,在青海湖流域北部部分地区人类活动的破坏力度仍大于建设力度;⑤ 冻土退化对青海湖流域草甸和灌丛植被覆盖度变化影响很小,主要影响草原植被覆盖度变化,冻土退化造成草原植被覆盖度增长速率减小了1.2%/10a。  相似文献   

2.
三江源是中国陆地生态系统最脆弱和敏感的区域之一,一旦遭到破坏则不可逆转。受三江源地区多云等不利气象条件的影响,很难获取大范围尺度上季相一致的、无云的Landsat遥感影像。本文利用Google Earth Engine平台,对1990-2015年的相同季节的3766景Landsat影像进行像元级融合并重构最小云量影像集,借助GEE的并行云端计算,快速得到了能够反映生态环境质量的遥感生态指数(RSEI),对三江源地区的生态环境质量进行了评价与监测。三江源时空变化与差异分析表明:1990-2000年生态环境质量呈快速下降状态,RSEI平均值从0.588下降到了0.505,生态环境质量变化以轻度恶化为主;2000-2015年生态环境质量下降速度变缓,并于2015年呈现变好态势,生态环境质量变化以不变为主,且轻度恶化面积大幅减少;该地区的生态环境状况呈现出空间分异,自西向东,生态状况变差。基于GEE平台在三江源地区的实验结果表明,GEE可以作为大区域范围的生态环境质量评价与监测的计算平台。  相似文献   

3.
湿地是水陆交错的生态系统,往往受旱灾影响大,故此,对不同湖泊湿地受旱程度差异及其原因分析,可为减灾和湿地保护提供科学依据。本文利用2010年5月和2011年5月2个时相的HJ-1卫星CCD影像,提取洪湖和梁子湖2个时相的湿地水面积,结合统计资料和问卷调查数据,从湿地水面积及空间分布变化、湿地生态系统功能退化、湿地生态系统,对人类福祉影响3方面,分析了两湖湿地受旱程度的差异。并综合气象数据、统计资料和问卷调查数据,从气象因子、区域自然地理环境、湿地类型及特点、区域水文条件和湿地受保护程度5方面探讨两湖受旱程度差异的原因。结果表明:(1)2011年春旱期间,洪湖比梁子湖受旱程度更严重。旱灾时,洪湖水面积减少83.93 km2,减小比例为26%,梁子湖水面积减少13.02 km2,减小比例为4%;两湖的涵养水源、保护生物多样性、物质生产和水质净化功能均受到损害,洪湖较梁子湖更严重;受旱灾影响,洪湖湿地对人类福祉的消极影响大于梁子湖。(2)降雨量、气温和风速等气象因素、湖泊湿地成因类型、区域自然地理环境和水文条件是影响两湖受旱程度差异的主要因素,另外,湿地保护措施的差异及效果也会造成两湖受旱程度不同。  相似文献   

4.
RELATIONSHIPBETWEENQINGHAILAKELEVELDESCENDINGANDARTIFICIALWATER-CONSUMPTION¥PengMin(彭敏)ChenGuichen(陈桂琛)ZhouLihua(周立华)(Northwe...  相似文献   

5.
青藏高原地区壮美的自然风光、神奇的人文景观和独特的民族文化,使其成为国内外旅游者倾心向往的世外桃源,亟需进一步探究其旅游经济与生态环境之间的交互耦合关系。本文创建青藏高原旅游经济与生态环境综合评价指标体系,采用青海省和西藏自治区15个地市州2000-2017年面板数据探究旅游经济与生态环境协调效应及交互胁迫关系。结果显示: ① 2000-2017年青藏高原仅有拉萨和西宁旅游经济指数呈现快速增长趋势,其余地市州均呈现缓慢增长趋势,生态环境指数整体较高,仅有西宁和海东呈现波动增长趋势,其余地市州变化平缓;② 青藏高原旅游经济与生态环境复合系统协调度时序上呈现波动增长趋势,空间上呈现南高北低、东高西低的分布格局;青海呈现以西宁为核心,逐层向外递减的核心-边缘空间格局;西藏呈现以拉萨为中心,南高北低的空间格局;③ 青藏高原复合系统协同效应子类型主要是旅游经济滞后型,西宁和拉萨呈现“旅游经济滞后-系统均衡发展-生态环境滞后”的变化趋势;④ 基于双指数模型证实了青藏高原旅游经济与生态环境之间具有交互胁迫关系。  相似文献   

6.
According to loess and palaeosol climatic record, field observation, analysis data and14C dating, we discuss the climatic changes and the water level fluctuations of Qinghai Lake. It is pointed out that there were four relatively warm and moist stages in Qinghai Lake basin during the Holocene. They formed in the periods from 10,300 yr.B.P. to 8,500 yr.B.P., 7,000 yr.B.P. to 3,500 yr.B.P., 2,800 yr.B.P. to 2,000 yr.B.P. and from 1,300 yr.B.P. up to now. the climate in the Holocene optimum period, from 7,000 yr.B.P. to 3,500 yr.B.P., was much warmer and moister than that today. Polypodium plant grew luxuriantly around Qinghai Lake. The annual temperature was 2.5°C higher than that today, but there was no forest at Qinghai Lake shore. It is found that there was a good relationship between precipitation and water level fluctuation. In warm and moist period water level was high and in the cold and dry period it was low in the Holocene. There were four high water level periods for Qinghai Lake in the Holocene, but the highest level was less than 30m above present water level. This research is supported by Youth Foundation of Natural Science Foundation of China (No. 49101015).  相似文献   

7.
秃尾河流域表生生态环境现状评价   总被引:1,自引:0,他引:1  
以地下水为主线,开展流域表生生态环境评价的方法研究尚处于发展之中。以秃尾河流域为例,紧紧围绕地下水这条主线,在建立流域表生生态环境递阶层次评价指标体系和评价标准的基础上,尝试采用模糊综合评判方法与模糊迭代自组织数据分析技术相结合,开展流域表生生态环境现状评价。评价结果表明,流域生态环境现状总体较好,其中盖沙丘陵区、河流源头和河谷阶地区及沙漠区是水资源与生态环境保护的重点,这些研究为评价生态环境脆弱区水资源开发利用对表生生态环境的影响以及保护流域水资源与生态环境提供了科学依据。评价结果与流域生态环境实际更为吻合,规律性更明显。  相似文献   

8.
遥感与GIS的青海湖岸线分维研究   总被引:2,自引:0,他引:2  
讨论了TM图像以及分形几何学对青海湖岸线问题的求解算法,同时估算了不同像元尺度下,青海湖的岸线长度得出青海湖岸线的分形维数为1.0237,并探讨了其地学意义,研究表明,分形维数不仅是一种可行的表达岸线特征的方法,而且岸线分维数的计算可大大减少工作量和提高工作效率,可见遥感与GIS技术在岸线分维数的计算中,具有十分良好的应用前景。  相似文献   

9.
The Taihu Lake region in southern Jiangsu is one of the regions with flourishing economy and the highest level of urbanization due to favourable natural conditions and socio-economic foundation. However, there emerge a seriers of urban ecological problems on continuous stretch of cities and towns, a vague division of urban functions, ground subsidence, serious pollution of atmosphere and waters arising from dense population, irrational distribution of industry, backwardeness of municipal engineering facilities, and inexperienced scientific management of water resources. In order to improve the urban eco-environment in this lake region, we should work out an overall regional eco梕nvironmental programme, perfect the urban economic set-up from the reqirements of urban material circulations and energy exchanges, and finally put into practice the urban functional regionalism, so that the Taihu Lake region in southern Jiangsu has not only a higher economic benefit, but also a beautiful and comfortable eco-env  相似文献   

10.
Causes and control countermeasures of eutrophication in Chaohu lake,China   总被引:3,自引:0,他引:3  
1 IN T R O D U C T IO NC haohu Lake,located in the centralA nhuiProvince ofC hina, has m ultiple functions of flood control, w atersupply,irrigation,transportation,fishery and tourism .Itis fam ous for its beautifullandscape and historic sites.For thousan…  相似文献   

11.
太湖蓝藻水华遥感动态监测预警模型的建立   总被引:7,自引:0,他引:7  
湖泊富营养化和蓝藻水华暴发是当前我国湖泊面临的最重要的环境问题之一。本文分析了内陆湖泊太湖蓝藻监测的主要问题。并详细阐述了蓝藻水华遥感动态监测预警模型的建立,即,采用生物光学模型与气象环境预警模型相结合的方式,辅以图形图像学的模块匹配验证,对蓝藻水华暴发前进行临界状态的灾害等级警示,理论上较单纯监测微囊藻叶绿素a浓度值来实现水华暴发预警更为准确。这样,提前采取相应的技术措施,减少蓝藻水华暴发带来的影响和损失。  相似文献   

12.
青海湖是我国最大的内陆咸水湖,是世界著名的湿地,但随着周围地区荒沙漠化环境的恶化,其土地荒漠化也不断加剧。本文对青海湖地区土地荒漠化的自然特征和社会经济特征进行了分析,明确了荒漠化的环境背景。在此基础上,结合青海湖地区荒漠化土地普查与监察工作的范围和内容,采用ASTER卫星影像图对湖区周围地区进行解译,并利用解译数据对荒漠化土地进行等级划分,分析土地荒漠化的空间分布格局,对荒漠化作出综合评价。  相似文献   

13.
INTRODUCTIONThedistingnishingc~teristicsofQinghaboe,thebiewstsalinelakeinCfuna,are:vastwaterm,higheleVation,closeddrinagbasinandattrativenaedland-scape.The~clakeleveldIDPsincethebegiwhngofthiscentwhascausedaseriesofenvironrnntalProblems(degenndionofghanggIaSSlandaIDunthelake,desertffica-tioninthebeacharea,aeOianerosionoftheeXposedlakebed,deCrainwaersuPPliesandincreaseinthewaterndnends).IncentalAsia,mostofthewell-knOWnlargelakes,includingla.kessuchasIssyk-kul(SeVaStyanvandSndmov,l…  相似文献   

14.
Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods flowed through Kusai and Hedin Noel Lakes into Yanhu Lake; since then, the four small endorheic catchments merged into one larger catchment. This hydrological process caused the rapid shrinkage of Zonag Lake and continuous expansion of Yanhu Lake. In this study,based on satellite images, meteorological data and field investigations, we examined the dynamic changes in the four lakes and analyzed the influencing factors. The results showed that before 2011, the trends in the four lake areas were similar and displayed several stages. The change in the area of Zonag Lake corresponded well to the change in annual precipitation(AP), but the magnitude of the change was less than that of a non-glacier-fed lake. Although increased precipitation was the dominant factor that caused Zonag Lake to expand, increased glacier melting and permafrost thawing due to climate warming also had significant effects. After the 2011 outburst of Zonag Lake, due to the increasing AP and accelerating glacier melting, the increases in water volume of the three lakes were absorbed by Yanhu Lake, and Yanhu Lake expanded considerably. According to the rapid growth rates in water level and lake area, Yanhu Lake is likely to burst in 1-2 years.  相似文献   

15.
Mongolia is an important country in the Economic Corridor of China-Mongolia-Russia, a deep understanding of the coupling relationship between urbanization and the eco-environment in Mongolia is meaningful to achieve green development of the Belt and Road. The entropy method and coupling coordination degree model were integrated to evaluate the coupling coordination degree between urbanization and the eco-environment in Mongolia during 2000-2016. The results showed that the coupling coordination degree between urbanization and the eco-environment in Mongolia was generally at the stage of seriously unbalanced development, and that the main contributor of the urbanization and the eco-environment subsystem were demographic urbanization and eco-environment endowment, respectively. The southern part of Mongolia central zone should be paid more attention due to the lower degree of coupling coordination between urbanization and the eco-environment. To promote the healthy urbanization development in Mongolia, six-layer eco-city establishing green development pattern is proposed to provide scientific support for Mongolia.  相似文献   

16.
青海作为长江、黄河、澜沧江的发源地,素有“中华民族水塔”之称。但是近十几年来,由于人类在该地区各种活动的影响,尤其是矿业活动,已造成该地区生态环境的不断恶化。通过列举矿业活动对生态环境破坏的主要表现,并从规范矿业活动、加强生态环境保护等方面提出了较为具体的措施。  相似文献   

17.
对遍及青海高原38个气象台站器测时期降水和气温分别进行聚类分析,得出3种不同变化类型的降水区域和3种气温区域,然后用MK突变分析方法和最优二级分割方法对各区域降水和气温气候序列进行均值和方差突变检测得出:青海高原大部分地区在60年代末出现了降水突变现象,80年代中后期普遍产生气温突变。  相似文献   

18.
基于气象监测网络的森林火险快速预警模型   总被引:1,自引:0,他引:1  
森林火灾发生频繁且突发性强,进行森林火险快速预警对于减小森林火灾损失和促进森林资源可持续发展至关重要。本文基于GIS空间分析和可视化技术,利用地面气象站构建实时气象监测网络,设计了运用气象监测网络的森林火险预警模型,可实现森林火险及时、快速预警。模型应用层次分析法建立了预警因子重要性层次结构并确定预警因子的权重;运用Voronoi图技术,基于气象站点和实时气象数据,构建气象监测网络;利用叠置分析技术计算得出预警结果。基于该模型设计的森林火灾快速预警系统应用于青海省林业局,验证了系统可行性与适用性,该模型可全面、准确、快速地实现对森林火险的预警。结果表明:① 根据预警模型及实时气象监测数据,可及时发出预警信号,快速实现县级、林场级别的森林火险早期预警和及时响应;② 运用GIS可视化技术,可快速生成相关区域森林火险的空间分布专题图,直观地观察预警等级的变化情况。实践表明,森林火险快速预警对森林火灾进行有效预防、中断管理和制定扑救措施具有重要的指导作用,并对森林防火工作、保护森林资源和人类生命财产安全具有重大意义。  相似文献   

19.
滇池污染的成因及其治理新方案   总被引:9,自引:0,他引:9  
本文对滇池的污染成因进行了综合分析。滇池污染是由两大因素造成的:一是水流太慢,二是污水南侵。从这两大污染因素可以找到两大对策:一是加速湖水流动,二是阻止污水南侵。基于滇池污染实际上是北部污染南部造成的,改变滇池出水口,开挖一条新河道,让滇池水倒流,滇池从原来的下游方换到上游方,城区污水不入滇池,即使进入也能让它快速从北部流出去,北部的污染负荷很容易从北部流出去,南部高水位的水位势压力阻止了北部负荷南侵,解决了滇池污染。  相似文献   

20.
An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessment. Then, a hierarchical model with four levels is established by virtue of these indicators and attributes. In the model, weights of indicators and attributes are determined by combining Delphi method with the Analytic Hierarchy Process (AHP) and a statistic method is used to eliminate the influences arising from the differences in dimension and magnitude of indicators. On these grounds, an AHP-statistics model is provided for regional eco-environmental quality assessment. As a case, such AHP-statistics model is utilized in the dynamic analysis of regional eco-environmental assessment in Chaohu Lake basin. Study results show that natural environmental quality in the watershed was in the declining state while social environmental quality was in a markedly improved situation from 1996, and the synthetic eco-environmental quality was gradually and slowly improved under the common influences of both natural and social environmental factors. Example of application testified the capacities of above methodology to evaluate the real and dynamic state of regional eco-environmental quality.  相似文献   

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