Variation of net primary productivity and its drivers in China’s forests during 2000–2018

Abstract

Background: Net primary productivity (NPP) in forests plays an important role in the global carbon cycle. However, it is not well known about the increase rate of China's forest NPP, and there are different opinions about the key factors controlling the variability of forest NPP. Methods: This paper established a statistics-based multiple regression model to estimate forest NPP, using the observed NPP, meteorological and remote sensing data in five major forest ecosystems. The fluctuation values of NPP and environment variables were extracted to identify the key variables influencing the variation of forest NPP by correlation analysis. Results: The long-term trends and annual fluctuations of forest NPP between 2000 and 2018 were examined. The results showed a significant increase in forest NPP for all five forest ecosystems, with an average rise of 5.2 gC•m − 2 •year − 1 over China. Over 90% of the forest area had an increasing NPP range of 0-161 gC•m − 2 •year − 1. Forest NPP had an interannual fluctuation of 50-269 gC•m − 2 •year − 1 for the five major forest ecosystems. The evergreen broadleaf forest had the largest fluctuation. The variability in forest NPP was caused mainly by variations in precipitation, then by temperature fluctuations. Conclusions: All five forest ecosystems in China exhibited a significant increasing NPP along with annual fluctuations evidently during 2000-2018. The variations in China's forest NPP were controlled mainly by changes in precipitation.

Accelerated increase in vegetation carbon sequestration in China after 2010: A turning point resulting from climate and human interaction

“…The accelerated increase in China's NPP after approximately 2010 was also revealed by these data sets, while the RESDC NPP data set showed only a slight NPP increase over 2001–2010. Moreover, most literature found that NPP in China did not show an obvious upward trend and may even decline from 2001 to around 2010 (Liang et al, 2015; Wang et al, 2017), probably due to the reduced solar radiation in southern China and droughts in southwest China (Ji et al, 2020; Wang et al, 2017).…”

Spatiotemporal Variation of Terrestrial Carbon Sequestration in Tropical Urban Area (Case Study in Surakarta District, Indonesia)

“…Based on Table 4, it can be seen that the NPP values between the urban and forest areas show very high disparity, even though they are both located in tropical areas. The difference in NPP values between these two areas is due to the vegetation density and variation type (Malhi et al 2011, Basuki et al 2019, Ji et al 2020, Yang et al 2020. Vegetation in forest areas has a high-density value compared to the vegetation in urban areas.…”

“…In addition, vegetation in urban areas, which tends to be homogeneous, makes the NPP value relatively small. The NPP value on land with low vegetation diversity (homogeneous) will be much smaller compared to that on land with high vegetation diversity (heterogeneous), such as in tropical forest areas (Malhi et al 2011, Ji et al 2020).…”

“…Therefore, the NPP value in these green open spaces has a relatively similar value during a year. The climatic factors that cause differences in the NPP value are rainfall, temperature and solar radiation intensity (Wang et al 2017, Ji et al 2020). When rainfall is high, plants get a lot of water to grow, so the photosynthesis process takes place intensively, which is indicated by the high value of NPP (lin et al 2017, Yangyang et al 2019.…”

Особливості Формування Первинної Продукції Лісів Карпатського НПП У Різних Лісорослинних Умовах

“…Актуальність дослідження продукції лісових екосистем відображена також у наукових роботах китайських науковців (Chen et al, 2020;Huang et al, 2020;Ji et al, 2020), які акцентують увагу на таких чинниках впливу як індекс листової поверхні, географічні характеристики території (довгота, широта) та видова різноманітність, погодні особливості (вологість і температурний режим) тощо.…”