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1.
1982-2013年中国植被NDVI空间异质性的气候影响分析   总被引:3,自引:1,他引:3  
为研究气候变化与植被活动之间的复杂关系,采用1982-2013年GIMMS NDVI与气象站点温度与水分的监测资料,应用基于像元的地理加权回归方法,探究了中国植被NDVI及其动态特征对气候变化响应的空间格局。中国植被NDVI与地表温度呈空间非平稳关系,在空间上的负相关关系主要集中在东北、西北及东南部分地区,空间正相关则更为集中和连片;针对不同气候指标的标准化系数对比可知,植被NDVI受水分控制作用较为显著的区域主要集中在北方地区以及青藏高原,温度的主导作用区域则分布在华东、华中及西南地区,其中年均最高气温对NDVI的主导区域范围最广;植被NDVI动态与气候变率的回归结果表明,增温速率的升高会通过加剧干旱等机制对植被活动产生抑制作用,水分变率对植被活动的强弱起到了重要的调节作用。  相似文献   

2.
归一化植被指数(NDVI)作为表征植被生长状况的关键性指标,能够有效的提供植被生长状况的信息。本研究基于1982–2015年哈萨克斯坦时间序列的GIMMS/NDVI数据,分析植被)生长的空间格局及变化趋势,研究结果表明:哈萨克斯坦自北向南分布着农田、草地、灌丛这三类主要的植被类型,呈明晰的地带性分布特征;植被指数由北到南逐渐降低,农田、草地和灌丛三类主要植被类型的NDVI均值水平依次为农田草地灌丛;1982–2015年间,NDVI呈现出先增长(1982–1992年)、再降低(1993–2007年)、然后又增长(2008–2015年)的变化趋势。NDVI显著下降的区域占土地总面积的24.0%,主要分布在西北部的农田与草地交错地带以及南部边缘的农田,草地退化面积占草地总面积的23.5%、农田退化面积占农田总面积的48.4%、灌丛退化面积占灌丛总面积的13.7%,植被改善的区域分布在中东部的农田以及农田与草地的交错带,显著提升的面积占土地总面积的11.8%。  相似文献   

3.
This study analyzed the spatial and temporal variations in the Normalized Difference Vegetation Index(NDVI) on the Mongolian Plateau from 1982–2013 using Global Inventory Modeling and Mapping Studies(GIMMS) NDVI3 g data and explored the effects of climate factors and human activities on vegetation. The results indicate that NDVI has slight upward trend in the Mongolian Plateau over the last 32 years. The area in which NDVI increased was much larger than that in which it decreased. Increased NDVI was primarily distributed in the southern part of the plateau, especially in the agro-pastoral ecotone of Inner Mongolia. Improvement in the vegetative cover is predicted for a larger area compared to that in which degradation is predicted based on Hurst exponent analysis. The NDVI-indicated vegetation growth in the Mongolian Plateau is a combined result of climate variations and human activities. Specifically, the precipitation has been the dominant factor and the recent human effort in protecting the ecological environments has left readily detectable imprints in the NDVI data series.  相似文献   

4.
Vegetation greenness is a key indicator of terrestrial vegetation activity. To under-stand the variation in vegetation activity in spring across eastern China (EC), we analysed the variation in the Normalised Difference Vegetation Index (NDVI) from April to May during 1982-2006. The regional mean NDVI across EC increased at the rate of 0.02/10yr (r2=0.28; p=0.024) prior to 1998; the increase ceased, and the NDVI dropped to a low level thereafter. However, the processes of variation in the NDVI were different from one region to another. In the North China Plain, a cultivated area, the NDVI increased (0.03/10yr; r2=0.52; p<0.001) from 1982 to 2006. In contrast, the NDVI decreased (-0.02/10yr; r2=0.24; p=0.014) consecu-tively from 1982 to 2006 in the Yangtze River and Pearl River deltas, two regions of rapid urbanisation. In the eastern region of the Inner Mongolian Plateau and the lower reaches of the Yangtze River in East China, the NDVI increased prior to 1998 and decreased thereafter. In the Hulun Buir area and the southern part of the Yangtze River Basin, the NDVI increased prior to 1998 and remained static thereafter. The NDVI in the grasslands and croplands in the semi-humid and semi-arid areas showed a significant positive correlation with precipitation, while the NDVI in the woodlands in the humid to semi-humid areas showed a significant positive correlation with temperature. As much as 60% of the variation in the NDVI was ex-plained by either precipitation or temperature.  相似文献   

5.
1982-2013年青藏高原植被物候变化及气象因素影响   总被引:12,自引:3,他引:9  
根据NDVI3g数据,本文定义了18种植被物候指标研究植被物候变化情况。根据1:100万植被区划,把青藏高原划分为8个植被区分。对物候变化比较显著的区域,采用最高温度、最低温度、平均温度、降水、太阳辐射数据,运用偏最小二乘法回归(PLS)研究物候变化的气候成因。结果表明:① 青藏高原生长季初期物候指标,转折发生在1997-2000年,转折前初期物候指标平均提前2~3 d/10a;青藏高原末期物候指标转折发生在2004-2007年左右,生长季长度物候指标突变发生在2005年左右,转折前末期物候指标平均延迟1~2 d/10a、生长季长度平均延长1~2 d/10a;转折之后生长季初期物候指标推迟趋势的显著性水平仅为0.1,生长季末期物候指标、生长季长度指标趋势不显著。② 高寒草甸与高寒灌木草甸是青藏高原物候变化最剧烈的植被分区。高寒草甸区生长季长度的延长主要是由生长季初期物候指标提前导致的。高寒灌木草甸区生长季长度的延长主要是由于初期物候指标的提前,以及末期物候指标的推迟共同作用导致的。③ 采用PLS进一步分析气象因素对高寒草甸与高寒灌木草甸物候剧烈变化的影响。表明,温度对物候的影响占主导地位,两植被分区均显示上年秋季、冬初温度对生长季初期物候具有正的影响,该时段温度一方面会导致上年末期物候指标推迟,间接推迟生长季开始时间;另一方面高温不利用冬季休眠。除夏季外,其余月份最小温度对植被物候的影响与平均温度、最高温度的影响类似。降水对植被物候的影响不同月份波动较大,上年秋冬季节降水对初期物候指标具有负的影响,春初降水对初期物候指标具有正的影响。8月份限制植被生长季的主要因素是降水,此时降水与末期物候指标模型系数为正。太阳辐射对植被物候的影响主要在夏季与秋初。PLS方法在物候变化研究中具有较好的效果,本文研究结果将会对植被物候模型改进,提供有力的科学依据。  相似文献   

6.
1982—2015年中国气候变化和人类活动对植被NDVI变化的影响   总被引:13,自引:1,他引:13  
基于中国603个气象站的地表气温和降水观测资料以及GIMMS NDVI3g数据,采用变化趋势分析和多元回归残差分析等方法研究了1982—2015年中国植被NDVI变化特征及其主要驱动因素(即气候变化和人类活动)的相应贡献。结果表明:① 1982—2015年中国植被恢复明显,在选择的32个省级行政区中,山西、陕西和重庆的生长季NDVI增加最快,仅上海生长季NDVI呈减小趋势。② 气候变化和人类活动的共同作用是中国植被NDVI呈现整体快速增加和巨大空间差异的主要原因,其中气候变化对各省生长季NDVI变化的影响在-0.01×10 -3~1.05×10 -3 a -1之间,而人类活动的影响在-0.32×10 -3~1.77×10 -3 a -1之间。③ 气候变化和人类活动分别对中国近34年来植被NDVI的增加贡献了40%和60%;人类活动贡献率超过80%的区域主要集中在黄土高原中部、华北平原以及中国东北和西南等地;人类活动贡献率大于50%的省份有22个,其中贡献率最大的3个地区为上海、黑龙江和云南。研究结果建议应更加重视人类活动在植被恢复中的作用。  相似文献   

7.
1982-2015年柴达木盆地不同流域植被气候响应差异   总被引:1,自引:0,他引:1       下载免费PDF全文
李博  曾彪  杨太保 《干旱区地理》2018,41(3):449-458
基于1982-2015年生长季(5~10月)GIMMS-MODIS融合数据、气象数据,利用一元线性回归和相关分析等方法研究柴达木盆地及各流域植被NDVI的时空演变及其与气候要素的关系。结果表明:(1)柴达木盆地植被整体上趋于改善,NDVI与气温和降水呈显著正相关。(2)盆地内各流域NDVI呈现不同程度的增长趋势,区域气候差异明显,盆地东部NDVI平均值与气温和降水的关系表现为以1989年和2002年为转折点的3段式特征,而盆地西部呈现出以1994-1995年为节点的2段式特征。(3)盆地东西部植被对气候要素响应的差异性显著,这可能与高原季风、西风环流及下垫面等因素有关。  相似文献   

8.
旨在为正确认识气候-植被的相互关系提供科学的理论指导。基于MOD13Q1的植被指数(NDVI和EVI)及气象站数据(极端最低温度、极端最高温度、平均最高温度、平均最低温度、平均温度;平均蒸气压、最低相对湿度、平均相对湿度、最大每日降水量、降水量;极端风速,最大风速,平均风速,日照时数,平均站气压),对阿拉善左旗两种典型植被指数对气候因子的响应差异展开全面研究。结果表明:MOD13Q1 NDVI和MOD13Q1 EVI对气候响应存在显著差异。同一气象站中,NDVI和EVI与气候因子的相关系数显著不同。同时,NDVI和EVI与气候因子的相关系数随着气象站的不同而存在显著差异。此外,NDVI对平均最低气温、平均气温、平均蒸汽压、最低相对湿度、极端风速、最大风速、平均风速及平均本站气压存在时滞效应;而EVI仅对平均最低气温、平均蒸汽压、极端风速、最大风速及平均本站气压存在时滞效应。时滞期多数集中在3月份。因此,不同的植被类型对气候的敏感度不同,且利用气象站数据进行与植被的相关研究时首先应关注气象站与植被的相关性,方可进行下一步的深入研究。  相似文献   

9.
Climate change is one of the most important factors that affect vegetation distribution in North China. Among all climatic factors, drought is considered to have the most significant effect on the environment. Based on previous studies, the climate drought index can be used to assess the evolutionary trend of the ecological environment under various arid climatic conditions. It is necessary for us to further explore the relationship between vegetation coverage(index) and climate drought conditions. Therefore, in this study, based on MODIS-NDVI products and meteorological observation data, the Palmer Drought Severity Index(PDSI) and vegetation coverage in North China were first calculated. Then, the interannual variations of PDSI and vegetation coverage during 2001–2013 were analyzed using a Theil-Sen slope estimator. Finally, an ecoregion perspective of the correlation between them was discussed. The experimental results demonstrated that the PDSI index and vegetation coverage value varied over different ecoregions. During the period 2001–2013, vegetation coverage increased in the southern and northern mountains of North China, while it showed a decreasing trend in the Beijing-Tianjin-Tangshan City Circle area and suburban agricultural zone located in Hebei Province and Henan Province). Over 13 years, the climate of the northeastern part of North China became more humid, while in the southern part of North China, it tended to be dry. According to the correlation analysis results, 73.37% of North China showed a positive correlation between the vegetation coverage and climate drought index. A negative correlation was observed mainly in urban and suburban areas of Beijing, Tianjin, Hebei Province, and Henan Province. In most parts of North China, drought conditions in summer and autumn had a strong influence on vegetation coverage.  相似文献   

10.
Health inequality is an increasing concern worldwide.Using the coefficient of variation,Theil index,exploratory spatial data analysis,and spatial panel econometric model,we examined the regional inequality,spatio-temporal dynamic patterns,and key factors in the health status of Chinese residents from 2003 to 2013.We found that China's residential health index(RHI) decreased from 0.404 to 0.295 in 2003–2013 at an annual rate of 2.698%.Spatially,resident health status,based on the RHI,has improved faster in the western region than in the eastern and central regions.Inequality in resident health status continued to increase between 2003 and 2013;inequality between regions decreased,but health status inequality expanded within regions.Furthermore,disparities in health status grew faster in western regions than in the eastern and central regions.The spatial distribution of resident health status formed a "T-shaped" pattern across China,decreasing from east to center then to the west with a symmetric decrease north and south.Using the change in Moran's I from 2003 to 2008 and 2013,we found that the distribution of resident health status across China has narrowed.All the hot spots and cold spots have decreased,but they are also stable.Resident health status formed a stable cold spot in the western regions,while the east coastal area formed a stable hot spot.Selected explanatory variables have significant direct impacts on resident health status in China:increasing per capita GDP,per capita spending on health,and urbanization,and improving environmental quality all lead to better resident health status.Finally,we highlight the need for additional research on regional inequality of resident health status across multiple time,spatial,and factor domains.  相似文献   

11.
The Heihe River Basin is located in the arid and semi-arid regions of Northwest China.Here,the terrestrial ecosystem is vulnerable,making it necessary to identify the factors that could affect the ecosystem.In this study,MODIS-NDVI data with a 250-m resolution were used as a proxy for the terrestrial ecosystem.By combining these with environmental factors,we were able to explore the spatial features of NDVI and identify the factors influencing the NDVI distribution in the Heihe River Basin during the period of 2000–2016.A geographical detector(Geodetector) was employed to examine the spatial heterogeneity of the NDVI and to explore the factors that could potentially influence the NDVI distribution.The results indicate that:(1) the NDVI in the Heihe River Basin appeared high in the southeast while being low in the north,showing spatial heterogeneity with a q-statistic of 0.38.The spatial trend of the vegetation in the three sub-basins generally increased in the growing seasons from 2000 to 2016;(2) The results obtained by the Geodetector(as denoted by the q-statistic as well as the degree of spatial association between the NDVI and environmental factors) showed spatial heterogeneity in the associations between the NDVI and the environmental factors for the overall basin as well as the sub-basins.Precipitation was the dominant factor for the overall basin.In the upper basin,elevation was found to be the dominant factor.The dominant factor in the middle basin was precipitation,closely followed by the soil type.In the lower basin,the dominant factor was soil type with a lower q-statistic of 0.13,and the dominant interaction between the elevation and soil type was nonlinearly enhanced(q-statistic = 0.22).  相似文献   

12.
从GIS空间关系角度分析,区别于前人通过生态学中土壤质地、生物量、碳存储、氧释放量和水体质量等微观层面评估生态系统服务价值,以地理空间数据为基础,空间分析为核心技术,对浏阳河流域生态系统服务价值的空间异质性进行了研究。首先以1×1 KM格网形式将流域划分,然后将地形、地质灾害点、道路、景点、关心点等人类活动热点分布以及植被覆盖度、植物净初级生产力作为影响因子,然后结合熵值法和层次分析法计算这些因子对生态系统每个服务价值的权重,权重可以反映对生态系统服务价值的影响的程度。受空间异质性影响每个格网都具有不同的空间特征,格网中土地利用类型种类数量不一,存在多种土地类型的格网就构成了微型景观,其复杂的物种组成,稳定的内部结构,提高自身调节,生态系统稳定性也就增强,因此这种景观格局方式使格网内生态服务总价值应该大于各生态系统服务价值代数累加之和。研究发现:9个指标因子中植被覆盖度、植物净初级生产力和道路分布情况对生态服务价值影响最显著,植被覆盖度高、植物净初级生产能力强,道路网密集会提高生态系统服务价值;不同土地类型主要的生态系统服务也不一样:耕地、草地和水体的供给服务、调节服务突出,林地的调节和支持服务突出;在各地类中,耕地和水体生态服务价值受空间异质性影响较大,因为耕地和水体与人类活动密切相关,受自然和人类双重因素影响,而林地和草地由于多位于远离人类的山地和丘陵区,主要受生物和地理环境影响,受空间异质性影响相对较弱。本研究针对生态系统服务价值评估,定量分析每个格网的自然和社会特征因素对生态服务价值估算影响,为精确科学评估生态服务价值提供参考。  相似文献   

13.
China's dryland region has serious wind erosion problem and is sensitive to climate change due to its fragile ecological condition. Wind erosion climatic erosivity is a measure of climatic factors influencing wind erosion, therefore, evaluation of its intensity and response to recent climate changes can contribute to the understanding of climate change effect on wind erosion risk. Using the FAO equation, GIS and statistical analysis tools, this study quantified the climatic erosivity, analyzed its spatiotemporal variations, and detected the trend and sensitivity to climate factors during 1961–2012. The results indicate that mean annual climatic erosivity was 2–166 at 292 stations and 237–471 at 6 stations, with the spatial distribution highly in accordance with wind speed(R2 = 0.94). The climatic erosivity varied greatly over time with the annual variation(CV) of 14.7%–108.9% and monthly variation(concentration degree) of 0.10–0.71 in the region. Meanwhile, annual erosivity showed a significant downward trend at an annual decreasing rate mostly above 1.0%. This significantly decreasing trend was mainly attributed to the obvious decline of wind speed during the period. The results suggest that the recent climate changes were highly possible to induce a decrease of wind erosion risk in China's dryland region.  相似文献   

14.
基于因子分析方法的中国植被NDVI与气候关系研究   总被引:12,自引:0,他引:12  
利用1982~2000年NDVI数据和气象台站资料,对我国几种植被型组和气候的相关关系进行了研究。首先利用NDVI结合植被类型图将我国植被划分为9种植被型组;然后利用因子分析方法进行了气候指标的选择并采用相对湿度、平均最高温度和平均风速作为本研究的气候因子;最后对7种植被型组NDVI值同相应季节及其前三个季节的气候指标进行了相关分析。结果表明,利用因子分析方法选择的气候指标可以较好地进行植被气候关系分析;在我国温度条件比水分条件更明显地影响植被的生长,水分条件较其他气候因素对植被生长表现了更明显的滞后效应;而平均风速则对我国荒漠植被生长有较大的影响。  相似文献   

15.
On the basis of two gridded datasets of daily precipitation and temperature with a spatial resolution of 0.5°×0.5°, and meteorological station data released by the National Meteorological Information Center(NMIC) during 1961–2013, the spatial and temporal variations of total amount of precipitation, amount of rainfall, amount of snowfall and snowfall/rainfall ratio(S/R) in the Tibetan Plateau(TP) are analyzed using Sen's slope, the Mann–Kendall mutation test, Inverse Distance Weighting(IDW) and the Morlet wavelet. Total amount of precipitation and amount of rainfall generally show statistically significant increasing trends of 0.6 mm·a~(–1) and 1.3 mm·a~(–1), respectively, while amount of snowfall and S/R have significant decreasing trends of –0.6 mm·a~(–1) and –0.5% a~(–1), respectively. In most regions, due to significant increasing trends in total amount of precipitation and amount of rainfall, and significant decreasing trends in amount of snowfall, S/R shows a decreasing trend in the TP. Abrupt changes in total amount of precipitation, amount of rainfall, amount of snowfall and S/R are detected for 2005, 2004, 1996 and 1998, respectively. Total amount of precipitation, amount of rainfall, amount of snowfall and S/R are concentrated in cycles of approximately 5 years, 10 years, 16 years and 20 years, respectively. The trend magnitudes for total amount of precipitation and amount of rainfall all show decreasing-to-increasing trends with elevation, while amount of snowfall and S/R show decreasing trends.  相似文献   

16.
蒸散是地球水循环的关键驱动因子,是地表水平衡和能量平衡的重要分量,因而也体现生态系统水文调节局地热调节功能;青藏高原是长江和黄河等重要河流的发源地,该区域水量平衡对区域生态安全具有重要意义。本文对全球尺度发展的遥感蒸散双源模型ARTS,利用涡度相关观测数据进行验证和评价,以空间插值的气象数据,卫星遥感的FPAR和LAI等驱动模型,估测1982-2014年间青藏高原实际蒸散ET,分析其年际和季节动态变化特征,并采用敏感性分析法和多元线性回归分析计算各气象因子变化对蒸散量变化的贡献率,探讨影响青藏高原蒸散量变化的主导因素。结果表明:(1)估测值能解释观测值季节变化的80%以上(复相关系数R~2=0.80,显著性水平P 0.001),表明模型具有较高的估算准确度。(2)近30多年全年、春、夏和秋季影响蒸散年际变化呈显著增加趋势;但变化趋势存在显著的区域分异,全年或夏季藏南河谷地区呈显著降低趋势(每10年降低20 mm以上),而阿里、拉萨河谷、青海海北地区则为增加趋势(每10年增加10 mm以上)。(3)敏感性分析和多元线性回归分析均表明,年际变化趋势的主导因素是气候变暖,其次是降水的不显著增加;但植被变化的影响也较大,与气候因子共同能够解释蒸散趋势的56%(多元线性回归方程R~2=0.56,P0.001);低覆盖草地多年蒸散分别是高、中覆盖度草地的26.9%和21.1%。青藏高原在显著变暖、不显著变湿的气候变化背景下,地表蒸散的增加必以冰川融水为代价而威胁区域生态环境安全,如何保护生态,维持区域社会可持续发展是难题和巨大挑战。  相似文献   

17.
Understanding biogeographic patterns and the mechanisms underlying them has been a main issue in macroecology and biogeography, and has implications for biodiversity conservation and ecosystem sustainability. Evergreen broad-leaved woody plants(EBWPs) are important components of numerous biomes and are the main contributors to the flora south of 35°N in China. We calculated the grid cell values of species richness(SR) for a total of 6265 EBWP species in China, including its four growth-forms(i.e., tree, shrub, vine, and bamboo), and estimated their phylogenetic structure using the standardized phylogenetic diversity(SPD) and net relatedness index(NRI). Then we linked the three biogeographical patterns that were observed with each single environmental variable representing the current climate, the last glacial maximum(LGM)–present climate variability, and habitat heterogeneity, using ordinary least squares regression with a modified t-test to account for spatial autocorrelation. The partial regression method based on a general linear model was used to decompose the contributions of current and historical environmental factors to the biogeographical patterns observed. The results showed that most regions with high numbers of EBWP species and phylogenetic diversity were distributed in tropical and subtropical mountains with evergreen shrubs extending to Northeast China. Current mean annual precipitation was the best single predictor. Topographic variation and its effect on temperature variation was the best single predictor for SPD and NRI. Partial regression indicated that the current climate dominated the SR patterns of Chinese EBWPs. The effect of paleo-climate variation on SR patterns mostly overlapped with that of the current climate. In contrast, the phylogenetic structure represented by SPD and NRI was constrained by paleo-climate to much larger extents than diversity, which was reflected by the LGM–present climate variation and topog-raphy-derived habitat heterogeneity in China. Our study highlights the importance of embedding multiple dimensions of biodiversity into a temporally hierarchical framework for understanding the biogeographical patterns, and provides important baseline information for predicting shifts in plant diversity under climate change.  相似文献   

18.
1982-2006 年中国东部春季植被变化的区域差异   总被引:9,自引:1,他引:9  
分析了中国东部1982-2006 年4-5 月归一化差值植被指数(NDVI) 的空间格局和变化趋势空间分布,通过聚类分析辨识了植被活动变化过程的主要模态,并探讨了他们与温度和降水变化的相关关系。结果表明:(1) 多年平均的春季植被活动呈现南强北弱的分布特征,由强到弱的过渡带大约位于34°~39°N;(2) 1982-2006 年,华北平原、呼伦贝尔草原和洞庭湖平原的春季植被活动呈显著增强的趋势,其中华北平原NDVI 增速高达0.03/10 年(r2 = 0.52;p <0.001),长三角和珠三角地区则呈显著减弱的趋势,其中长三角地区NDVI减速达-0.016/10 年(r2 = 0.24;p = 0.014);(3) 1982-2006 年春季植被活动变化过程的区域差异鲜明,并呈现层次性特征,首先是长三角和珠三角与其他地区的差异,前者呈减弱趋势,后者呈增强趋势,其次是呼伦贝尔草地、华北以及江南—华南地区与东北地区、内蒙古东部和东南部及长江下游地区的差异,前者持续增强,后者以1998 年为分界点先增强后减弱,再次是各个模态年际变率的差异;(4) 半湿润—半干旱的草地和农田区植被活动与降水量变化显著正相关,半湿润—湿润的森林区植被活动与温度变化显著正相关,温度或者降水最高能解释NDVI 60%的方差。  相似文献   

19.
气候是影响区域宜居性的一个重要自然因素。人居环境气候适宜性深刻影响着区域人口分布和社会经济发展。西藏地区是气候变化的敏感地区,近年来随着全球气候变化的影响,该地区的气候适宜性也发生了显著变化。本文基于多年平均气候数据计算了西藏地区的温湿指数,定量分析了人口分布与温湿指数之间的关系;在此基础之上,确定了西藏地区气候适宜性分区标准;最后评价了西藏地区的人居环境气候适宜性。结果表明:西藏东南部地区年均温度相对较高,人口分布相对密集;年均相对湿度整体上呈现出由南向北逐渐降低的趋势。西藏气候适宜地区(包括高度适宜地区、比较适宜地区和一般适宜地区)面积占比仅为7.90%,人口数量比重超过40%。气候临界适宜地区面积占比为37.81%,人口占比为48.24%。气候不适宜地区广泛分布于各地市,面积占比为54.29%,人口占比为11.33%。本文的研究结果可为指导西藏地区人口的合理分布以及优化国土空间规划提供参考。  相似文献   

20.
There is a lack of simple ways to predict the vegetation responses to the East Asian Monsoon(EAM) variability in China due to the complexity of the monsoon system. In this study, we found the variation of the Western Pacific Subtropical High(WPSH), which is one of the major components of the EAM, has a profound influence on the vegetation growth in China. When the WPSH is located more to the west of its climate average, the eastern and northwestern parts experience increased yearly-averaged normalized difference vegetation index(NDVI) and gross primary productivity(GPP) by 0.3%–2.2%, and 0.2%–2.2%, respectively. In contrast, when the WPSH is located more to the east of its climate average, the above areas experience decreased yearly-averaged NDVI and GPP by 0.4% to 1.6%, and 1.3% to 4.5%, respectively. The WPSH serves as a major circulation index to predict the response of vegetation to monsoon.  相似文献   

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