Spatio-temporal evolution patterns of carbon budget in the Xinjiang Production and Construction Corps

This paper comprehensively and accurately calculated carbon budgets at the county level and explored their spatio-temporal evolution patterns， aiming to identify pathways for low-carbon economic development suited to each county and to contribute to achieving the carbon peaking and carbon neutrality goals of the Xinjiang Production and Construction Corps. From the perspectives of the entire terrestrial ecosystem and human activities encompassing energy consumption and human respiration， this study constructed a relatively comprehensive， accurate， and unified spatial model for measuring and evaluating carbon emissions， carbon absorption， and carbon budgets across spatial and temporal dimensions. This model was used to measure carbon absorption by the terrestrial ecosystem， human-induced carbon emissions， and carbon budgets in the Xinjiang Production and Construction Corps and its constituent divisions from 2010 to 2020， exploring their spatio-temporal evolution patterns at different scales， specifically the city and county levels. In addition， based on the economy contributive coefficient （ECC） and ecological support coefficient （ESC）， this paper conducted carbon balance zoning for each division. The results showed that： 1） The total carbon absorption of the terrestrial ecosystem consistently represented net carbon absorption， showing a continuous and slow decreasing trend， with carbon sequestration capacity in persistent decline. The only carbon source， cultivated land， expanded rapidly year by year in the direction of carbon sinks such as forests and grasslands. Human-induced carbon emissions exhibited a continuous and steady upward trend， although their growth rate began to decline sharply after 2015. Spatially， they presented a distribution pattern of "high in the north and east， low in the south and west". 2） Carbon emissions/absorptions underwent a process of rapid increase from 2010 to 2015， followed by slower growth from 2015 to 2020. Energy consumption was the most significant source of carbon emissions. The carbon emissions generated on construction land within each division accounted for 95% of the total carbon emissions/absorptions， reaching 99% for the entire study area. In terms of spatial distribution， except for the 14th Agricultural Division （characterized by vast land and sparse population and functioning as a net carbon absorber）， the other 12 divisions were all net carbon emitters， showing an obvious spatial differentiation pattern of "high in the north and east， low in the south and west". The high-value areas exhibited spatial consistency with the distribution of human-induced carbon emissions， expanding eastward from the 8th Agricultural Division in the Junggar Basin of northern Xinjiang. By 2020， the 8th， 13th， and 6th Agricultural Divisions （accounting for 26.52% of the land area） had emerged as high-density carbon emission zones， collectively bearing 78.16% of the net carbon emissions. 3） During the study period， both the high-carbon optimization zones and the low-carbon maintenance zones showed an expansion trend. In 2020， the divisions comprised one carbon sink functional zone， nine low-carbon maintenance zones， and three high-carbon optimization zones. The high-carbon optimization zones were distributed in a strip-shaped pattern， concentrated in the central and eastern areas， accounting for approximately 26.52% of the total area.