Spatial and temporal change patterns of net primary productivity and its response to climate change in the Qinghai-Tibet Plateau of China from 2000 to 2015

Terrestrial net primary productivity (NPP) plays an essential role in the global carbon cycle as well as for climate change. However, in the past three decades, terrestrial ecosystems across mainland China suffered from frequent drought and, to date, the adverse impacts on NPP remain uncertain. This study explored the spatiotemporal features of NPP and discussed the influences of drought on NPP across mainland China from 1982 to 2015 using the Carnegie Ames Stanford Application (CASA) model and the standardized precipitation evapotranspiration index (SPEI). The obtained results indicate that: (1) The total annual NPP across mainland China showed an non-significantly increasing trend from 1982 to 2015, with annual increase of 0.025 Pg C; the spring NPP exhibited a significant increasing trend (0.031 Pg C year−1, p < 0.05) while the summer NPP showed a higher decreasing trend (0.019 Pg C year−1). (2) Most areas of mainland China were spatially dominated by a positive correlation between annual NPP and SPEI and a significant positive correlation was mainly observed for Northern China; specific to the nine sub-regions, annual NPP and SPEI shared similar temporal patterns with a significant positive relation in Northeastern China, Huang-Huai-Hai, Inner Mongolia, and the Gan-Xin Region. (3) During the five typical drought events, more than 23% areas of mainland China experienced drought ravage; the drought events generally caused about 30% of the NPP reduction in most of the sub-regions while the NPP in the Qinghai-Tibet Plateau Region generally decreased by about 10%.

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The Relative Contributions of Climate and Grazing on the Dynamics of Grassland NPP and PUE on the Qinghai-Tibet Plateau

Remote Sensing ◽

10.3390/rs13173424 ◽

2021 ◽

Vol 13 (17) ◽

pp. 3424

Author(s):

Huilin Yu ◽

Qiannan Ding ◽

Baoping Meng ◽

Yanyan Lv ◽

Chang Liu ◽

...

Keyword(s):

Climate Change ◽

Interannual Variation ◽

Net Primary Productivity ◽

Climatic Factors ◽

Grazing Intensity ◽

Tibet Plateau ◽

Dominant Factor ◽

Vegetation Growth ◽

The Past ◽

Qinghai Tibet Plateau

Net primary productivity (NPP) and precipitation-use efficiency (PUE) are crucial indicators in understanding the responses of vegetation to global change. However, the relative contributions of climate change and human interference to the dynamics of NPP and PUE remain unclear. During the past few decades, the impacts of climate change and human activities on alpine grasslands on the Qinghai-Tibet Plateau (QTP) have been intensifying. The aims of the study were to investigate the spatiotemporal patterns of grassland NPP and PUE on the QTP during 2000–2017 and quantify how much of the variance in NPP and PUE can be attributed to the climatic factors (precipitation and temperature) and grazing intensity. The results showed that: (1) grassland NPP significantly increased with a rate of 0.6 g C m−2 year−1 over the past 18 years, mainly induced by the increased temperature and the enhanced precipitation. The temperature was the dominant factor for NPP interannual variation in mid-eastern QTP, and precipitation restrained vegetation growth most in the southwest and northeast. (2) The PUE was higher on the eastern and western parts of the plateau, but lower at the center. Regarding grassland types, the PUE of alpine steppe (0.19 g C m−2 mm−1) was significantly lower than those of alpine meadow (0.31 g C m−2 mm−1) and desert steppe (0.32 g C m−2 mm−1). (3) Precipitation was significantly and negatively correlated with PUE and contributed the most to the temporal variation of grassland PUE on the QTP (52.7%). (4) Furthermore, we found that the grazing activities had the lowest contributions to both NPP and PUE interannual variation, compared to temperature and precipitation. Thus, it is suggested that climate variability rather than grazing activities dominated vegetation changes on the QTP.

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Phylogeny and biogeography of Primula sect. Armerina: implications for plant evolution under climate change and the uplift of the Qinghai-Tibet Plateau

BMC Evolutionary Biology ◽

10.1186/s12862-015-0445-7 ◽

2015 ◽

Vol 15 (1) ◽

Cited By ~ 18

Author(s):

Guangpeng Ren ◽

Elena Conti ◽

Nicolas Salamin

Keyword(s):

Climate Change ◽

Plant Evolution ◽

Tibet Plateau ◽

Qinghai Tibet Plateau

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Driving mechanisms of gross primary productivity geographical patterns for Qinghai–Tibet Plateau lake systems

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.148286 ◽

2021 ◽

pp. 148286

Author(s):

Junjie Jia ◽

Yafeng Wang ◽

Yao Lu ◽

Kun Sun ◽

Sidan Lyn ◽

...

Keyword(s):

Primary Productivity ◽

Gross Primary Productivity ◽

Tibet Plateau ◽

Geographical Patterns ◽

Driving Mechanisms ◽

Plateau Lake ◽

Lake Systems ◽

Qinghai Tibet Plateau

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Spatial and Temporal Differences in Alpine Meadow, Alpine Steppe and All Vegetation of the Qinghai-Tibetan Plateau and Their Responses to Climate Change

Remote Sensing ◽

10.3390/rs13040669 ◽

2021 ◽

Vol 13 (4) ◽

pp. 669

Author(s):

Hanchen Duan ◽

Xian Xue ◽

Tao Wang ◽

Wenping Kang ◽

Jie Liao ◽

...

Keyword(s):

Climate Change ◽

Alpine Meadow ◽

Global Climate ◽

Growing Season ◽

Tibet Plateau ◽

Vegetation Types ◽

Analysis Method ◽

Alpine Steppe ◽

Qinghai Tibet Plateau ◽

Variation Trends

Alpine meadow and alpine steppe are the two most widely distributed nonzonal vegetation types in the Qinghai-Tibet Plateau. In the context of global climate change, the differences in spatial-temporal variation trends and their responses to climate change are discussed. It is of great significance to reveal the response of the Qinghai-Tibet Plateau to global climate change and the construction of ecological security barriers. This study takes alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau as the research objects. The normalized difference vegetation index (NDVI) data and meteorological data were used as the data sources between 2000 and 2018. By using the mean value method, threshold method, trend analysis method and correlation analysis method, the spatial and temporal variation trends in the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau were compared and analyzed, and their differences in the responses to climate change were discussed. The results showed the following: (1) The growing season length of alpine meadow was 145~289 d, while that of alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau was 161~273 d, and their growing season lengths were significantly shorter than that of alpine meadow. (2) The annual variation trends of the growing season NDVI for the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau increased obviously, but their fluctuation range and change rate were significantly different. (3) The overall vegetation improvement in the Qinghai-Tibet Plateau was primarily dominated by alpine steppe and alpine meadow, while the degradation was primarily dominated by alpine meadow. (4) The responses between the growing season NDVI and climatic factors in the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau had great spatial heterogeneity in the Qinghai-Tibet Plateau. These findings provide evidence towards understanding the characteristics of the different vegetation types in the Qinghai-Tibet Plateau and their spatial differences in response to climate change.

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