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Increasing terrestrial vegetation activity in China, 1982–1999
Jingyun Fang,Shilong Piao,Jinsheng He,Wenhong Ma
Science China Life Sciences , 2004, DOI: 10.1007/BF03182768
Abstract: Variations in vegetation activity during the past 18 years in China were investigated using the normalized difference vegetation index (NDVI) derived from the 3rd generation time series dataset of NOAA-AVHRR from 1982 to 1999. In order to eliminate the effects of non-vegetation factors, we characterized areas with NDVI < 0.1 as “sparsely vegetated areas” and areas with NDVI ≥0.1 as “vegetated areas”. The results showed that increasing NDVI trends were evident, to varying extents, in almost all regions in China in the 18 years, indicating that vegetation activity has been rising in recent years in these regions. Compared to the early 1980s, the vegetated area increased by 3.5% by the late 1990s, while the sparsely vegetated area declined by 18.1% in the same period. The national total mean annual NDVI increased by 7.4% during the study period. Extended growing seasons and increased plant growth rates accounted for the bulk of these increases, while increases in temperature and summer rainfall, and strengthening agricultural activity were also likely important factors. NDVI changes in China exhibited relatively large spatial heterogeneity; the eastern coastal regions experienced declining or indiscernibly rising trends, while agricultural regions and western China experienced marked increases. Such a pattern was due primarily to urbanization, agricultural activity, regional climate characteristics, and different vegetation responses to regional climate changes.
Climate change, growing season water deficit and vegetation activity along the north-south transect of Eastern China from 1982 through 2006
P. Sun,Z. Yu,S. Liu,X. Wei
Hydrology and Earth System Sciences Discussions , 2012, DOI: 10.5194/hessd-9-6649-2012
Abstract: Considerable work has been done to examine the relationship between environmental constraints and vegetation activities represented by the remote sensing-based Normalized Difference Vegetation Index (NDVI). However, the relationships along either environmental or vegetation type gradients are rarely examined. The aim of this paper was to identify the vegetation types that are potentially susceptible to climate change through examining the interaction between vegetation activity and water deficit. We selected 12 major vegetation types along the north-south transect of Eastern China (NSTEC), examined their time trends from 1982 to 2006 with respect to climate change, vegetation activity and water deficit. The results showed that all vegetation types experienced warming during the study period, and the majority of them experienced precipitation decline. Warming and growing season water deficit exert counteracting controls on vegetation activity. Our study found insignificant greening trends in the northernmost cold temperate coniferous forest (CTCF), three temperate herbaceous types including the meadow steppe (TMS), grass steppe (TGS) and grassland (TG), where the growing season warming exerted more than offset effect on vegetation activity (phenology) than growing season water deficit. For the three temperate forest including the coniferous (TCF), mixed (TMF) and deciduous-broadleaved (TDBF), growing season water deficit was the main constraint on vegetation activity. Differently, the growing season browning in subtropical or tropical forests of coniferous (STCF), deciduous-broadleaved (SDBF) and evergreen-broadleaved (SEBF) and subtropical grasslands (STG) were likely attributed to decline in sunshine duration due to increased summer cloudiness. Poor water status in TDS, TG, TMS and severe drought in TGS have been identified by using growing season water deficit index (GWDI), suggested these ecosystems were subjected to severe progressing drought that may create greening trend reversal in future. The emerging water deficit in CTCF, TCF and SDBF suggested their rising susceptibility to future climate change.
Climate change, growing season water deficit and vegetation activity along the north–south transect of eastern China from 1982 through 2006
P. Sun, Z. Yu, S. Liu, X. Wei, J. Wang, N. Zegre,N. Liu
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2012,
Abstract: Considerable work has been done to examine the relationship between environmental constraints and vegetation activities represented by the remote sensing-based normalized difference vegetation index (NDVI). However, the relationships along either environmental or vegetational gradients are rarely examined. The aim of this paper was to identify the vegetation types that are potentially susceptible to climate change through examining their interactions between vegetation activity and evaporative water deficit. We selected 12 major vegetation types along the north–south transect of eastern China (NSTEC), and tested their time trends in climate change, vegetation activity and water deficit during the period 1982–2006. The result showed significant warming trends accompanied by general precipitation decline in the majority of vegetation types. Despite that the whole transect increased atmospheric evaporative demand (ET0) during the study period, the actual evapotranspiration (ETa) showed divergent trends with ET0 in most vegetation types. Warming and water deficit exert counteracting controls on vegetation activity. Our study found insignificant greening trends in cold temperate coniferous forest (CTCF), temperate deciduous shrub (TDS), and three temperate herbaceous types including the meadow steppe (TMS), grass steppe (TGS) and grassland (TG), where warming exerted more effect on NDVI than offset by water deficit. The increasing growing season water deficit posed a limitation on the vegetation activity of temperate coniferous forest (TCF), mixed forest (TMF) and deciduous broad-leaved forest (TDBF). Differently, the growing season brownings in subtropical or tropical forests of coniferous (STCF), deciduous broad-leaved (SDBF), evergreen broad-leaved (SEBF) and subtropical grasslands (STG) were likely attributed to evaporative energy limitation. The growing season water deficit index (GWDI) has been formulated to assess ecohydrological equilibrium and thus indicating vegetation susceptibility to water deficit. The increasing GWDI trends in CTCF, TCF, TDS, TG, TGS and TMS indicated their rising susceptibility to future climate change.
Variation trends of China terrestrial vegetation net primary productivity and its responses to climate factors in 1982-2000.
我国陆地植被净初级生产力变化规律及其对气候的响应

HOU Ying-Yu,LIU Qin-Huo,YAN Hao,TIAN Guo-Liang,
侯英雨
,柳钦火,延昊,田国良

应用生态学报 , 2007,
Abstract: A new estimation model of vegetation net primary production (NPP) based on remote sensing data and climatic data was presented, with which, the NPP of China terrestrial vegetation in 1982-2000 was estimated, and the intra-and inter-annual variation patterns of the NPP and its responses to climate factors were studied. The results showed that there was an obvious seasonal regularity in the intra-annual variation of the NPP. In 1982-2000, all the terrestrial vegetation types presented an increasing annual NPP, with the greatest increment for deciduous needle leaf forests and the smallest one for grasses. Evergreen broadleaf forests had the largest inter-annual variation, while grasses had the smallest one. Comparing with temperature, precipitation played a stronger driving role in the intra-annual variation of the NPP, and the effects of precipitation and temperature were more obvious in North China than in South China. The driving roles of the climate factors varied with season and latitude.
Comprehensive analysis of the impact of climatic changes on Chinese terrestrial net primary productivity
WenQuan Zhu,YaoZhong Pan,XiaoQiong Yang,GuoBao Song
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-0521-5
Abstract: Recent climatic changes have affected terrestrial net primary productivity (NPP). This paper presents an investigation of the impact of climatic changes on Chinese terrestrial vegetation NPP by analyzing 18 years’ (1982 to 1999) climatic data and satellite observations of vegetation activity. Results indicate that climatic changes in China have eased some critical climatic constraint on plant growth. (1) From 1982 to 1999, modeled NPP increased by 1.42%·a 1 in water-limited regions of Northwest China, 1.46%·a 1 in temperature-limited regions of Northeast China and Tibet Plateau, and 0.99%·a 1 in radiation-limited regions of South China and East China. (2) NPP increased by 24.2%, i.e. 0.76 petagram of carbon (Pg C) over 18 years in China. Changes in climate (with constant vegetation) directly contributed nearly 11.5% (0.36 Pg C). Changes in vegetation (with constant climate) contributed 12.4% (0.40 Pg C), possibly as a result of climate-vegetation feedbacks, changes in land use, and growth stimulation from other mechanisms. (3) Globally, NPP declined during all three major El Ni o events (1982 to 1983, 1987 to 1988, and 1997 to 1998) between 1982 and 2000, but Chinese vegetation productivity responded differently to them because of the monsoon dynamics. In the first three events (1982 to 1983, 1987 to 1988, and 1992), Chinese vegetation NPP declined, while in the later two events (1993, 1997 to 1998) increasing obviously.
Seasonal Changes in Vegetation Activity in Response to Climate Changes in China between 1982 and 1999
1982-1999年我国陆地植被活动对气候变化响应的季节差异

PIAO Shilong,FANG Jingyun,
朴世龙
,方精云

地理学报 , 2003,
Abstract: In the present study, using normalized difference vegetati on index (NDVI) as an indicator of vegetation activity, seasonal trends of vegetation activity and their dynamic responses to climate changes in China were explored based on remotely sensed data (NOAA-AVHRR) from 1 982 to 1999. As a result, spatially averaged seasonal NDVI in China showed a pronounced increase in all four seasons (spring, summer, autumn and win ter) during the past 18 years. The average spring NDVI indicated the most significant increase (P<0.001) with a mean rate of 1.3%, while the average autumn NDVI showed the least increase (P=0.075). Analyzing int erannual changes in seasonal mean NDVI by vegetation type, it was fou nd that the advance of growing season was a major way for response of vegetation activity to climate changes and that the way exhibited a large regional heterogeneity. In the past 18 years, regions with the largest increase rate of summer NDVI appeared in Northwest China and the Tibetan Plateau, while areas with that of spring NDVI occurred i n the eastern part of the country.
An Analysis of Vegetation Change Trends and Their Causes in Inner Mongolia, China from 1982 to 2006  [PDF]
Baolin Li,Wanli Yu,Juan Wang
Advances in Meteorology , 2011, DOI: 10.1155/2011/367854
Abstract: This paper presents the vegetation change trends and their causes in the Inner Mongolian Autonomous Region, China from 1982 to 2006. We used National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) data to determine the vegetation change trends based on regression model by fitting simple linear regression through the time series of the integrated Normalized Difference Vegetation Index (NDVI) in the growing season for each pixel and calculating the slopes. We also explored the relationship between vegetation change trends and climatic and anthropogenic factors. This paper indicated that a large portion of the study area (17%) had experienced a significant vegetation increase at the 0.05 level from 1982 to 2006. The significant vegetation increase showed no positive link with precipitation and was mainly caused by human activities. In or to the south of Horqin Sandy Land, in the Hetao Plain, and at the northern foothills of the YinshanMountain, the significant NDVI increase trends were mainly caused by the increase of the millet yield per unit of cropland. In the east of Ordos Plateau, the significant NDVI increase trends were mainly determined by the fencing and planting of grasses and trees on grassland. 1. Introduction Desertification is one of the most serious regional environmental issues [1]. China is one of the major countries facing this problem in the world. The total area of desertification-prone land was approximately 2.62 million km2, occupying 27.3% of the total area of China [2]. The Inner Mongolian Autonomous Region, located in the north of China, is a typical agriculture-grazing transitional zone that has been seriously affected by desertification and has suffered from severe wind erosion and a high frequency of dust storms [3]. Thus, it is very important to determine the vegetation change trends for combating the desertification in this area. With the accumulation of remotely sensed images over the past three decades, research on desertification based on monitoring vegetation change has been conducted from national to regional scales [4–9]. Fang et al. [4] and Piao et al. [5] reported that the vegetation in arid and semiarid areas of China increased significantly according to the analyses of NOAA/AVHRR data from 1982 to 1999. These results suggested a reversal of the desertification processes in these regions. This research attributed the major cause of the vegetation increase to precipitation change. According to the research above, human activity was only responsible for a minor part of the
An Analysis of Vegetation Change Trends and Their Causes in Inner Mongolia, China from 1982 to 2006  [PDF]
Baolin Li,Wanli Yu,Juan Wang
Advances in Meteorology , 2011, DOI: 10.1155/2011/367854
Abstract: This paper presents the vegetation change trends and their causes in the Inner Mongolian Autonomous Region, China from 1982 to 2006. We used National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) data to determine the vegetation change trends based on regression model by fitting simple linear regression through the time series of the integrated Normalized Difference Vegetation Index (NDVI) in the growing season for each pixel and calculating the slopes. We also explored the relationship between vegetation change trends and climatic and anthropogenic factors. This paper indicated that a large portion of the study area (17%) had experienced a significant vegetation increase at the 0.05 level from 1982 to 2006. The significant vegetation increase showed no positive link with precipitation and was mainly caused by human activities. In or to the south of Horqin Sandy Land, in the Hetao Plain, and at the northern foothills of the YinshanMountain, the significant NDVI increase trends were mainly caused by the increase of the millet yield per unit of cropland. In the east of Ordos Plateau, the significant NDVI increase trends were mainly determined by the fencing and planting of grasses and trees on grassland.
Empirical Evidence for Impacts of Internal Migration on Vegetation Dynamics in China from 1982 to 2000  [PDF]
Conghe Song,Jackson W. Lord,Liming Zhou,Jingfeng Xiao
Sensors , 2008, DOI: 10.3390/s8085069
Abstract: Migration is one of the major socio-economic characteristics of China since the country adopted the policy of economic reform in late 1970s. Many studies have been dedicated to understand why and how people move, and the consequences of their welfare. The purpose of this study is to investigate the environmental impacts of the large scale movement of population in China. We analyzed the trend in the Normalized Difference Vegetation Index (NDVI) from the Advanced Very High Resolution Radiometer (AVHRR) along with China migration data from the 1 percent national survey during 1982-1987, the 4th national census during 1985-1990 and the 5th national census during1995~2000. We found that the internal migration in China has a statistically significant negative impact on vegetation growth at the provincial scale from 1982 to 2000 even though the overall vegetation abundance increased in China. The impact from migration (R2=0.47, P=0.0001) on vegetation dynamics is the second strongest as among the factors considered, including changes in annual mean air temperature (R2=0.50, P=0.0001) and annual total precipitation (R2=0.30, P=0.0049) and gross domestic production (R2= 0.25, P=0.0102). The negative statistical relationship between the rate of increase in total migration and the change in vegetation abundance is stronger (R2=0.56, P=0.0000) after controlling for the effects of changes in temperature and precipitation. In-migration dominates the impacts of migration on vegetation dynamics. Therefore, it is important for policy makers in China to take the impacts of migration on vegetation growth into account while making policies aiming at sustainable humanenvironment relations.
Empirical Evidence for Impacts of Internal Migration on Vegetation Dynamics in China from 1982 to 2000
Conghe Song,Jackson W. Lord,Liming Zhou,Jingfeng Xiao
Sensors , 2008,
Abstract: Migration is one of the major socio-economic characteristics of China since the country adopted the policy of economic reform in late 1970s. Many studies have been dedicated to understand why and how people move, and the consequences of their welfare. The purpose of this study is to investigate the environmental impacts of the large scale movement of population in China. We analyzed the trend in the Normalized Difference Vegetation Index (NDVI) from the Advanced Very High Resolution Radiometer (AVHRR) along with China migration data from the 1 percent national survey during 1982-1987, the 4th national census during 1985-1990 and the 5th national census during1995~2000. We found that the internal migration in China has a statistically significant negative impact on vegetation growth at the provincial scale from 1982 to 2000 even though the overall vegetation abundance increased in China. The impact from migration (R2=0.47, P=0.0001) on vegetation dynamics is the second strongest as among the factors considered, including changes in annual mean air temperature (R2=0.50, P=0.0001) and annual total precipitation (R2=0.30, P=0.0049) and gross domestic production (R2= 0.25, P=0.0102). The negative statistical relationship between the rate of increase in total migration and the change in vegetation abundance is stronger (R2=0.56, P=0.0000) after controlling for the effects of changes in temperature and precipitation. In-migration dominates the impacts of migration on vegetation dynamics. Therefore, it is important for policy makers in China to take the impacts of migration on vegetation growth into account while making policies aiming at sustainable humanenvironment relations.
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