Spatio-temporal evolution and agglomeration characteristics of agricultural production carbon sink in Henan Province

There are carbon emission and carbon absorption in agricultural production. Research on carbon sinks in agricultural production lacks clear system boundary, less medium scale researches and uniformity and integrity in accounting. To solve the above problems, this study analyzed the evolution trend and agglomeration characteristics using the Gene's coefficient and Lorenz curve methods through determining carbon sinks in agricultural production in Henan Province. The main results showed that agricultural production systems in Henan Province generally had carbon sink characteristic, and its carbon sequestration had been increased from 2000 to 2015. Carbon sinks in agricultural production in Henan Province amounted to 3.24×10⁷ tons in 2015, which was 22.53% of carbon emission driven by energy consumption in the province. Therefore, agricultural production had a positive ecological effect on decreasing greenhouse gas. There was gradual increase in the carbon sink due to agricultural production for the period from 2000 to 2015 as carbon absorption increased much faster than carbon emission with increasing agricultural modernization and agricultural production capacity. As far as structure was concerned, agricultural production was the main aspect of the natural function of carbon emission in Henan Province, was 70.15% of total carbon emission in agricultural production in 2015. Carbon emission via artificial agricultural input increased relatively faster than the natural function of carbon emission, which was the main reason for the increase in carbon emission via agricultural production in the province. The annual growth rates of carbon emission due to artificial agricultural input were respectively 0.85% and 3.27% in 2000 and 2015, which was 3.85 times that of the natural factors of carbon emission. The spatial distribution of carbon sink due to agriculture production in Henan Province showed universality, relative stability and significant agglomeration, with significant differences between the north and south and then east and west. The values of carbon sinks for agricultural production in the eastern and northern regions were relatively high, while those for southern and western regions were relatively low.