Interannual variability of terrestrial net ecosystem productivity over China: regional contributions and climate attribution

Abstract

China's terrestrial ecosystems play an important role in the global carbon cycle. Regional contributions to the interannual variation (IAV) of China's terrestrial carbon sink and the attributions to climate variations are not well understood. Here we have investigated how terrestrial ecosystems in the four climate zones with various climate variabilities contribute to the IAV in China's terrestrial net ecosystem productivity (NEP) using modeled carbon fluxes data from six ecosystems models. Model results show that the monsoonal region of China dominates national NEP IAV with a contribution of 86% (69%-96%) on average. Yearly national NEP changes are mostly driven by gross primary productivity IAV and half of the annual variation results from NEP changes in summer. Regional contributions to NEP IAV in China are consistent with their contributions to the magnitude of national NEP. Rainfall variability dominates the NEP annual variability in China. Precipitation in the temperate monsoon climate zone makes the largest contribution (23%) to the IAV of NEP in China because of both the high sensitivity of terrestrial ecosystem carbon uptake to rainfall and the large fluctuation in the precipitation caused by the East Asian summer monsoon anomalies. Our results suggest that NEP IAV can be mainly attributed to ecosystems with larger productivity and response to precipitation, and highlight the importance of monsoon climate systems with high seasonal and interannual variability in driving internannual variation in the land carbon sink.

The Impact of the 20–50-Day Atmospheric Intraseasonal Oscillation on the Gross Primary Productivity between the Yangtze and Yellow Rivers

“…Therefore, although significant negative correlations are identified between the filtered GPP and temperature over the Hetao area (348-408N, 1058-1108E; Fig. 3c), contrary to the previous works that positive (negative) temperature anomalies tend to increase (decrease) the photosynthetic activity of grassland over eastern China (He et al 2007;Zhang et al 2019), it might indicate the influence of precipitation on 2-m temperature and GPP, rather than the direct FIG. 3.…”

How the Updated Earth System Models Project Terrestrial Gross Primary Productivity in China under 1.5 and 2 °C Global Warming

“…A climate division map of China was applied for regional analysis. It divided the country into four climate zones-i.e., temperate continental, temperate monsoonal, subtropicaltropical monsoonal, and high-cold Tibetan Plateau, as in He et al [15] and Zhang et al [16].…”

Response of Growing Season Gross Primary Production to El Niño in Different Phases of the Pacific Decadal Oscillation over Eastern China Based on Bayesian Model Averaging

“…The capacity of terrestrial GPP to partly offset anthropogenic CO 2 emissions is especially important for China, where the emissions of fossil fuel CO 2 into the atmosphere are high (Gregg et al, 2008). The subtropical forests in eastern China can take in a considerable amount of CO 2 (Yu et al, 2014), and contribute remarkably to the total carbon sequestration of Chinese ecosystems (Zhang et al, 2019a). The climate in eastern China is dominated by the East Asian Summer Monsoon (EASM), which is one of the most active components in the global climate system and can significantly affect the movement of local rain belts (Ding et al, 2008).…”

“…The climate in eastern China is dominated by the East Asian Summer Monsoon (EASM), which is one of the most active components in the global climate system and can significantly affect the movement of local rain belts (Ding et al, 2008). Given the ecological importance of the monsoon climate in China and the high sensitivity of the carbon uptake of ecosystems in EASM region to rainfall (Dan et al, 2015;Zhang et al, 2019a), it is important to develop a deeper understanding of the response of GPP to the variability in rainfall during the EASM.…”