Drivers and Environmental Impacts of Vegetation Greening in a Semi-Arid Region of Northwest China since 2000

The dynamics of terrestrial vegetation have changed a lot due to climate change and direct human interference. Monitoring these changes and understanding the mechanisms driving them are important for better understanding and projecting the Earth system. Here, we assessed the dynamics of vegetation in a semi-arid region of Northwest China for the years from 2000 to 2019 through satellite remote sensing using Vegetation Index (VI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS), and analyzed the interannual covariation between vegetation and three climatic factors—air temperature, precipitation, and vapor pressure deficit (VPD)—at nine meteorological stations. The main findings of this research are: (1) herbaceous land greened up much more than forests (2.85%/year vs. 1.26%/year) in this semi-arid region; (2) the magnitudes of green-up for croplands and grasslands were very similar, suggesting that agricultural practices, such as fertilization and irrigation, might have contributed little to vegetation green-up in this semi-arid region; and (3) the interannual dynamics of vegetation at high altitudes in this region correlate little with temperature, precipitation, or VPD, suggesting that factors other than temperature and moisture control the interannual vegetation dynamics there.

[1]  P. Ciais,et al.  Variations in satellite‐derived phenology in China's temperate vegetation , 2006 .

[2]  Y. Lü,et al.  Revegetation in China’s Loess Plateau is approaching sustainable water resource limits , 2016 .

[3]  Jianping Huang,et al.  Accelerated dryland expansion regulates future variability in dryland gross primary production , 2020, Nature Communications.

[4]  Ranga B. Myneni,et al.  Amazon Forests' Response to Droughts: A Perspective from the MAIAC Product , 2016, Remote. Sens..

[5]  R. B. Jackson,et al.  A Large and Persistent Carbon Sink in the World’s Forests , 2011, Science.

[6]  Ranjeet John,et al.  Land cover/land use change in semi-arid Inner Mongolia: 1992–2004 , 2009 .

[7]  Ranga B. Myneni,et al.  Temperature and vegetation seasonality diminishment over northern lands , 2013 .

[8]  F. Maestre,et al.  Structure and functioning of dryland ecosystems in a changing world. , 2016, Annual review of ecology, evolution, and systematics.

[9]  P. Ciais,et al.  Characteristics, drivers and feedbacks of global greening , 2019, Nature Reviews Earth & Environment.

[10]  C. Liang,et al.  Ecological restoration impact on total terrestrial water storage , 2020, Nature Sustainability.

[11]  Yi Y. Liu,et al.  Contribution of semi-arid ecosystems to interannual variability of the global carbon cycle , 2014, Nature.

[12]  P. Ciais,et al.  Air temperature optima of vegetation productivity across global biomes , 2019, Nature Ecology & Evolution.

[13]  Yaowen Xie,et al.  Driving Factors of Recent Vegetation Changes in Hexi Region, Northwest China Based on a New Classification Framework , 2020, Remote. Sens..

[14]  Matthew O. Jones,et al.  Sunlight mediated seasonality in canopy structure and photosynthetic activity of Amazonian rainforests , 2015 .

[15]  Philippe Ciais,et al.  Evidence for a weakening relationship between interannual temperature variability and northern vegetation activity , 2014, Nature Communications.

[16]  J. Canadell,et al.  Greening of the Earth and its drivers , 2016 .

[17]  Luis Guanter,et al.  Agricultural Green Revolution as a driver of increasing atmospheric CO2 seasonal amplitude , 2014, Nature.

[18]  C. Peng,et al.  Multiple afforestation programs accelerate the greenness in the 'Three North' region of China from 1982 to 2013 , 2016 .

[19]  Yi Y. Liu,et al.  Detecting dryland degradation using Time Series Segmentation and Residual Trend analysis (TSS-RESTREND) , 2017 .

[20]  Mark A. Friedl,et al.  Direct human influence on atmospheric CO2 seasonality from increased cropland productivity , 2014, Nature.

[21]  Zhenghong Tang,et al.  Assessing the Three-North Shelter Forest Program in China by a novel framework for characterizing vegetation changes , 2017 .

[22]  Jonas Ardö,et al.  Evaluating Water Controls on Vegetation Growth in the Semi-Arid Sahel Using Field and Earth Observation Data , 2017, Remote. Sens..

[23]  Xinhua He,et al.  Balancing green and grain trade , 2015 .

[24]  Atul K. Jain,et al.  The dominant role of semi-arid ecosystems in the trend and variability of the land CO2 sink , 2015, Science.

[25]  Alessandro Cescatti,et al.  Satellites reveal contrasting responses of regional climate to the widespread greening of Earth , 2017, Science.

[26]  Liming Zhou,et al.  Afforestation in China cools local land surface temperature , 2014, Proceedings of the National Academy of Sciences.

[27]  Bin Chen,et al.  Stable classification with limited sample: transferring a 30-m resolution sample set collected in 2015 to mapping 10-m resolution global land cover in 2017. , 2019, Science bulletin.

[28]  Zeyu Liu,et al.  Greening and Browning of the Hexi Corridor in Northwest China: Spatial Patterns and Responses to Climatic Variability and Anthropogenic Drivers , 2018, Remote. Sens..

[29]  Yaowen Xie,et al.  Detecting Patterns of Vegetation Gradual Changes (2001-2017) in Shiyang River Basin, Based on a Novel Framework , 2019, Remote. Sens..

[30]  J. Thepaut,et al.  Supplementary material to "ERA5-Land: A state-of-the-art global reanalysis dataset for land applications" , 2021, Earth System Science Data.

[31]  J. Michaelsen,et al.  The climate hazards infrared precipitation with stations—a new environmental record for monitoring extremes , 2015, Scientific Data.

[32]  M. Gocić,et al.  Analysis of changes in meteorological variables using Mann-Kendall and Sen's slope estimator statistical tests in Serbia , 2013 .

[33]  A. Rogers,et al.  Elevated CO2 effects on plant carbon, nitrogen, and water relations: six important lessons from FACE. , 2009, Journal of experimental botany.

[34]  J. Townshend,et al.  Global land change from 1982 to 2016 , 2018, Nature.

[35]  Junliang Fan,et al.  Optimization of drip irrigation and fertilization regimes for high grain yield, crop water productivity and economic benefits of spring maize in Northwest China , 2020 .

[36]  C. Tucker,et al.  Climate-Driven Increases in Global Terrestrial Net Primary Production from 1982 to 1999 , 2003, Science.

[37]  Ziyue Chen,et al.  Drought dominates the interannual variability in global terrestrial net primary production by controlling semi-arid ecosystems , 2016, Scientific Reports.

[38]  R. Myneni,et al.  Reduced streamflow in water-stressed climates consistent with CO2 effects on vegetation , 2016 .

[39]  C. Tucker,et al.  Increased plant growth in the northern high latitudes from 1981 to 1991 , 1997, Nature.

[40]  S. Seneviratne,et al.  Soil moisture dominates dryness stress on ecosystem production globally , 2020, Nature Communications.

[41]  Pierre Gentine,et al.  Sensitivity of grassland productivity to aridity controlled by stomatal and xylem regulation , 2017 .

[42]  R. Bailey,et al.  Spatial and temporal signatures of fragility and threshold proximity in modelled semi-arid vegetation , 2011, Proceedings of the Royal Society B: Biological Sciences.

[43]  Philippe Ciais,et al.  Seasonal responses of terrestrial ecosystem water‐use efficiency to climate change , 2016, Global change biology.

[44]  Atul K. Jain,et al.  Increased atmospheric vapor pressure deficit reduces global vegetation growth , 2019, Science Advances.

[45]  R. Nemani,et al.  Biophysical impacts of Earth greening largely controlled by aerodynamic resistance , 2020, Science Advances.

[46]  Z. Wan.  New refinements and validation of the collection-6 MODIS land-surface temperature/emissivity product , 2014 .

[47]  P. Ciais,et al.  Evaporative cooling over the Tibetan Plateau induced by vegetation growth , 2015, Proceedings of the National Academy of Sciences.

[48]  V. Brovkin,et al.  China and India lead in greening of the world through land-use management , 2019, Nature Sustainability.

[49]  Niklaus E. Zimmermann,et al.  Water-use efficiency and transpiration across European forests during the Anthropocene , 2015 .