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1.
基于2000-2017年石羊河流域NDVI时间系列数据,利用Landsat系列卫星的TM、ETM、OLI数据获取了研究区的NDVI;并根据NDVI时序变化特征,利用趋势分析法,结合气象数据,研究了近18a来石羊河流域NDVI时空演变的规律。研究结果表明:①2000-2017年石羊河流域时序NDVI总体呈上升趋势,说明植被覆盖程度具有明显增长的趋势;②不同区域NDVI变化差异明显,总体可划分为显著增加、增加、稳定、减少、显著减少5类;③年际NDVI平均值、最大值与气温、降水相关性分析表明,二者与气温相关性在2000-2010年为负相关、在2011-2017年为正相关,二者与降水量总体呈正相关,相关系数分别为0.09、0.29,降水量的增大有利于促进石羊河流域植物的生长。  相似文献   

2.
长江上游安宁河流域植被生长变化对气候条件的响应   总被引:1,自引:0,他引:1  
为探讨安宁河流域植被演变趋势及其与气候的相互作用,基于2001—2008年MODIS图像、降水量和气温数据,采用回归分析和相关分析等方法计算了安宁河流域降水、气温和归一化差值植被指数(normalized difference vegetation index,NDVI)在时间和空间上的变化情况,并对安宁河流域植被生长变化对气候条件的响应机制进行了探讨。结果表明:NDVI变化和气温、降水呈正相关;降水量和气温等气候因子的变动会直接反映在植被长势上,其中降水对安宁河流域植被生长的影响更为显著;植被长势与气温和降水存在一定的时间滞后性。  相似文献   

3.
近30年来渭河流域植被与气候变化互影响模式的探寻分析   总被引:2,自引:0,他引:2  
基于1982-2006年间的GIMMS NDVI和2001-2013年的MODIS NDVI数据对渭河流域30年来植被NDVI的年际变化和空间分布特征进行了分析,并结合研究区内的气象数据探讨了植被NDVI与气候因子的相互影响关系。研究显示,近32年间渭河流域植被NDVI整体呈上升趋势,且空间差异显著,主要表现为流域西北地区的黄土丘陵沟壑区及北部的黄土高原区NDVI较低,植被覆盖较差;流域南部的秦岭山区、关中平原区等地植被生长状况较好。流域气温和降水呈现缓慢增长趋势。植被NDVI与年均气温整体上表现为负相关,与年降水量间呈正相关。总体上,降水是渭河流域植被生长的主要影响因子。  相似文献   

4.
针对不同地区植被变化对气温和降水的响应不一致的现象,该研究基于MODIS-NDVI遥感影像及同期33个气象站点数据,采用斜率分析和相关分析等方法,探究了河西地区2000-2017年生长季植被覆盖的年际和年内变化及其与气候因子的关系.结果表明:河西地区生长季NDVI的总体水平偏低,空间上由东南向西北逐步递减;近18年,河西地区NDVI的趋势变化为整体增加,增加速率为0.022/(10 a).年尺度上,河西地区NDVI变化与气温相关性较小,主要受降水影响,86.80%的区域与降水呈正相关.月尺度上,植被覆盖随温度升高而逐渐增加,20℃时趋于最大;月降水量在0~60 mm之间时,NDVI随降水量增大而快速增加;超过60 mm后,则稳定在0.16左右.河西地区植被对降水的响应存在2个月滞后性,而与气温则无明显时滞性.  相似文献   

5.
在全球气候变化背景下研究陆地植被的时空变化规律,探讨气候因素的驱动作用,对于预测未来气候变化对生态系统的可能影响、制定合适的生态环境保护策略具有重要意义。利用2000—2009年MODIS归一化差值植被指数(normalized difference vegetation index,NDVI)时间序列数据和地面气象站点的气温、降水量数据,从遥感角度分析环渤海地区植被的时空变化,并研究变化与气温、降水的相关关系,探讨区域植被年内和年际变化的驱动因素。结果表明,2000—2009年环渤海地区植被覆盖总体呈增加的趋势,但存在一定的空间异质性,局部有减少的倾向;区域植被的生长受温度和降水的双重驱动,对降水和温度的响应存在明显的滞后,滞后期大约为1个合成期;年际的变化主要受降水和人类活动的影响,降水增加可使区域NDVI提高;不同的人类活动会导致NDVI向相反的方向发展。  相似文献   

6.
为分析山东省植被覆盖度变化及其与降水量、温度等气候因子变化的相关性,该文采用2005—2015年的NDVI、降水量和温度数据,利用重心模型和相关系数法,进行了植被覆盖度与降水、温度的月动态变化和季度动态变化分析。研究结果显示,在2005—2015年的10年间,山东省植被覆盖度在整体上呈现增长趋势,植被覆盖度与气候因子无论是在月动态变化还是季动态变化都表现出不同程度的正相关性,植被NDVI的季度走向与降水和温度的季动态变化趋势几乎一致,并且温度对植被生长的影响大于降水对植被生长的影响。研究验证了植被覆盖度的变化与气候因子的变化有一定的关系。  相似文献   

7.
沈斌  房世波  余卫国 《遥感学报》2016,20(3):481-490
植被指数是反映地表植被覆盖状况的重要参数,分析气候因子与植被指数间的相互关系有助于揭示气候变化对植被的影响,然而当前研究有两种分析植被指数与气候因子关系的方法,分别为分析植被指数与生长季内和生长季间气候因子的关系,然而这两种法差异如何,何种方法更为合适需要进一步分析。利用2000年—2009年生长季的MODIS的归一化植被指数NDVI(Normalized Difference Vegetation Index)数据集和藏北那曲地区3个气象站逐月气象资料(月平均气温、≥0℃活动积温和月降水量),分析比较了生长季内和生长季间气候因子对植被生长影响的差异,并分析了两种方法的优劣。结果表明:(1)生长季内植被NDVI与同期气温和降水量均呈高度正相关,生长季内时滞时间尺度为1个月时,植被NDVI对月平均气温及降水响应均最为强烈。(2)生长季间NDVI与同期降水量相关性并不明显,气候因子的滞后效应在生长季间也较弱。(3)生长季内和生长季间植被NDVI与气候因子的关系所得出的结论有一定差异性,可能是因为两方面的原因:生长季内植被NDVI与水热因子的高相关性与中国季风季候造成的高温多雨出现在夏季有关,而生长季内高水热条件与高植被指数对应的多年重复必然造伪的高相关系数,但这种相关性不一定能真实反映植被与水热条件的关系,而生长季间水热等气候因子与植被指数年际变化相关性分析不存在水热与高植被指数同期问题,更能真实反映气候因子年际变化对植被的影响。  相似文献   

8.
本文利用时序的NDVI数据及气象资料(气温、降水),对羌塘国家自然保护区东、中、西部各县近10年NDVI、气温、降水变化及其相关性进行分析。研究表明,近10年来,保护区东部NDVI呈显著上升趋势,植被覆盖增加,中部和西部呈下降趋势,植被覆盖减少,东部年均NDVI与气温呈显著正相关、与降水呈显著负相关,中部反之;西部年均NDVI与气温、降水均呈显著负相关。  相似文献   

9.
基于获取的塔河流域2000~2014年历年4~10月间逐月MODIS植被指数产品,采用时间序列谐波分析法(HANTS)对最大值合成的逐月NDVI时间序列数据进行了重建,用趋势线分析法对塔河流域近15年生长季(4~10月)MODIS NDVI的时间变化进行计算,用一元线性回归趋势法计算得到了塔河流域近15年生长季(4~10月)NDVI变化趋势的空间分布。结合植被类型分布图对计算得到的实验结果进行了研究分析,总结了塔河流域多年植被覆盖的时空分布及其变化规律,成果可为塔河流域综合治理及生态环境评价提供依据。  相似文献   

10.
针对内蒙古不同生态区植被长势时空变化及其对气候变化的响应差异问题,本文基于MODIS遥感数据构建植被长势指数(GI)模型,结合研究区气温降水数据,利用相关分析法研究了该区植被长势对不同气候因子响应的时空差异特征.结果表明:内蒙古近17a生长季植被GI整体呈上升趋势,森林生态区和草原生态区植被长势平稳,荒漠草原生态区植被长势较好;生长季植被GI均值在空间上呈南高北低的分布特征,植被长势整体由好到差表现为荒漠草原生态区>森林生态区>草原生态区;植被长势与气温呈负相关关系、与降水呈正相关关系;森林生态区植被长势受气温和降水共同影响,草原生态区和荒漠草原生态区植被长势主要受降水影响;大部分地区表现为受非气候因子驱动.  相似文献   

11.
针对鄂尔多斯高原植被覆盖变化受干旱胁迫的状况,该文结合降水和气温的协同变化,以2000-2012年生长季的MODIS-NDVI数据和同期降水、温度和帕尔默干旱指数为依据,采用线性趋势分析、标准偏差分析和相关性分析等方法,对鄂尔多斯高原植被与气候变化的相关关系和干旱异常变化对植被动态的影响进行了研究.结果表明:鄂尔多斯高原生长季及季节(春季、夏季和秋季)植被归一化植被指数主要受降水的控制和干旱的制约,秋季归一化植被指数更多地受到夏季干旱的影响.与气象因子的空间相关分析表明,春季温度上升有利于研究区北部归一化植被指数像元的增加.在荒漠草原和沙漠地区,夏季干旱与归一化植被指数的相关关系最强.秋季降水对典型草原归一化植被指数的提升显著.  相似文献   

12.
以三江源区为研究区,主要利用一元线性趋势法和简单相关分析法分析了源区1982~2004年生长季累积NDVI的时间序列变化特征及其与气温、降雨、光照时间、风速、地表温度这些气候因子之间的相关性,从月尺度上研究了三江源区植被NDVI对气候因子响应的滞后性特征。最后表明,生长季累积NDVI对气温的滞后期为1个月,对风速的滞后期为2个月,对地表温度的滞后期为4个月,而对降雨量和日照时数不存在滞后响应或者滞后期小于1个月。  相似文献   

13.
Using NOAA/AVHRR 10-day composite NDVI data and 10-day meteorological data, including air temperature, precipitation, vapor pressure, wind velocity and sunshine duration, at 19 weather stations in the three-river-source region in the Qinghai–Tibetan Plateau in China from 1982 to 2000, the variations of NDVI and climate factors were analyzed for the purpose of studying the correlation between climate change and vegetation growth as represented by NDVI in this region. Results showed that the NDVI values in this region gradually grew from the west to the east, and the distribution was consistent with that of moisture status. The growing season came earlier due to climate warming, yet because of the reduction of precipitation, maximal NDVI during 1982–2000 did not show a significant change. NDVI related positively to air temperature, vapor pressure and precipitation, but negatively related to sunshine duration and wind velocity. Furthermore, the response of NDVI to climate change showed time lags for different climate factors. Water condition and temperature were found to be the most important factors effecting the variation of NDVI during the growing season in both the semi-arid and the semi-humid areas. In addition, NDVI had a better correlation with vapor pressure than with precipitation. The ratio of precipitation to evapotranspiration, representing water gain and loss, can be regarded as a comprehensive index to analyze NDVI and climate change, especially in areas where the water condition plays a dominant role.  相似文献   

14.
A growing number of studies have focused on variations in vegetation phenology and their correlations with climatic factors. However, there has been little research on changes in spatial heterogeneity with respect to the end of the growing season (EGS) and on responses to climate change for alpine vegetation on the Qinghai–Tibetan Plateau (QTP). In this study, the satellite-derived normalized difference vegetation index (NDVI) and the meteorological record from 1982 to 2012 were used to characterize the spatial pattern of variations in the EGS and their relationship to temperature and precipitation on the QTP. Over the entire study period, the EGS displayed no statistically significant trend; however, there was a strong spatial heterogeneity throughout the plateau. Those areas showing a delaying trend in the EGS were mainly distributed in the eastern part of the plateau, whereas those showing an advancing trend were mostly scattered throughout the western part. Our results also showed that change in the vegetation EGS was more closely correlated with air temperature than with precipitation. Nonetheless, the temperature sensitivity of the vegetation EGS became lower as aridity increased, suggesting that precipitation is an important regulator of the response of the vegetation EGS to climate warming. These results indicate spatial differences in key environmental influences on the vegetation EGS that must be taken into account in current phenological models, which are largely driven by temperature.  相似文献   

15.
齐丹宁  胡政军  赵尚民 《测绘通报》2021,(9):98-102,107
研究采矿扰动区内植被变化规律,能够为矿区生态修复提供理论依据。本文以山西省西山煤田为研究区,通过设立对比试验区,利用MODIS/NDVI(2001-2019年)结合同期的气温、降水气候因子,分别从植被指数的时空变化及与气象因子之间的关系等方面展开对比,用于探究采矿扰动区内植被变化情况。研究结果表明:①19年来西山煤田与间接影响区及校验区的植被均呈增加趋势,但西山煤田相比于校验区NDVI均值低11.42%。②西山煤田相较于自然生态条件下植被增长率为-5.53%。③西山煤田与校验区的NDVI值均受到气温、降水两种气象因子的影响,但是与降水的相关性更高,即受降水影响更大。  相似文献   

16.
海河流域NDVI对气候变化的响应研究   总被引:6,自引:1,他引:5  
以海河流域为研究区,利用8 km分辨率AVHRR/NDVI数据和气象资料,逐像元对1981-2000年时段的流域NDVI值、年降水量和年均气温的变化率进行分析,计算了NDVI和年降水量、年均气温的相关关系.结果表明,1981-2000年时段内,海河流域年降水量变化总体呈现北部和南部增加,中部减少的趋势,其变化范围在-8...  相似文献   

17.
Multitemporal NOAA/AVHRR NDVI images and monthly temperature and precipitation data were obtained across Yangtze River basin covering the period 1981–2001. The spatial and temporal patterns of NDVI are the same, while spatial analysis shows that the NDVI is influenced by the vegetation types growing in the study regions, and NDVI presents an increasing trend during the study period in the whole basin. The climate indicators play an important role in the changes of vegetation cover in the river basin. In the two Indicators, temperature has a significant effect on the NDVI values than precipitation in the whole basin. However, in the 11 subbasins, the different rules are shown in different subbasins.  相似文献   

18.
Climate dominantly controls vegetation over most regions at most times, and vegetation responses to climate change are often asymmetric with temporal effects. However, systematic analysis of the time-lag and time-accumulation effects of climate on vegetation growth, has rarely been conducted, in particular for different vegetation growing phases. Thus, this study aimed to leverage normalized difference vegetation index (NDVI) to determine the spatiotemporal patterns of climatic effects on global vegetation growth considering various scenarios of time-lag and/or accumulation effects. The results showed that (i) climatic factors have time-lag and -accumulation effects as well as their combined effects on global vegetation growth for the whole growing season and its subphases (i.e., the growing and senescent phases). However, these effects vary with climatic factors, vegetation types, and regions. Compared with those of temperature, both precipitation and solar radiation display more significant time-accumulation effects in the whole growing season worldwide, but behave differently in the growing and senescent phases in the middle-high latitudes of the Northern Hemisphere; (ii) compared to the scenario without time effects, considering time-lag and -accumulation effects as well as their combined effects increased by 17 %, 15 %, and 19 % the overall explanatory power of vegetation growth by climate change for the whole growing season, the growing phase, and senescent phase, respectively; (iii) considering the time-lag and -accumulation effects as well as their combined effects, climate change controls 70 % of areas with a significant NDVI variation from 1982 to 2015, and the primary driving factor was temperature, followed by solar radiation and precipitation. This study highlights the significant time-lag and -accumulation effects of climatic factors on global vegetation growth. We suggest that these effects need to be incorporated into dynamic vegetation models to better understand vegetation growth under accelerating climate change.  相似文献   

19.
In this paper, we apply lagged correlation analysis to study the effects of vegetation cover on the summer climate in different zones of China, using NOAA/AVHRR normalized difference vegetation index (NDVI) data during the time period from 1982 to 2001 and climate data of 365 meteorological stations across China (precipitation from 1982 to 2001 and temperature from 1982 to 1998). The results show that there are positive correlations between spring NDVI and summer climate (temperature and precipitation) in most zones of China; these suggest that, when the vegetation cover increases, the summer precipitation will increase, and the lagged correlations show a significant difference between zones. The stronger correlations between NDVI in previous season and summer climate occur in three zones (Mid-temperate zone, Warm-temperate zone and Plateau climate zone), and this implies that vegetation changes have more sensitive feedback effects on climate in the three zones in China.  相似文献   

20.
利用2000-2015年植被生长季(4~10月)MODIS/NDVI产品反演生成同时相的植被覆盖度数据,运用趋势性分析方法和皮尔逊相关系数法,进行了不同类型自然植被覆盖度时空变化特征及其与降水量、平均气温的驱动因素分析。结果表明从多年平均状态看,针叶林的植被覆盖度高于其他天然植被,灌丛类的最低,荒漠和灌丛类的植被覆盖度总体呈递增趋势;从年际尺度上看,草原和灌丛类植被对气温和降水量的响应规律大致呈反方向;不同类植被在春季(4月)对气温和降水量反映的差异性最大,与春季为新疆融雪高峰期有一定关系。  相似文献   

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