Progress has been made in the study of the impact of land reclamation on soil organic carbon in the arid area where Xinjiang is located

To ensure food security for a growing population, expanding agricultural activities have a profound impact on
global soil organic carbon stocks.
However, there is still great uncertainty about the impact of natural ecosystem reclamation for arable land on soil organic carbon, especially in arid areas
, which account for 45.
36% of the world's total land area.
This undermines better understanding of regional and national carbon dynamics, and weakens the credibility
of active agricultural measures to combat climate change.
Therefore, it is of great significance
to improve the understanding of regional soil organic carbon stocks by land reclamation.

In view of the above problems, the land change and ecology simulation team of Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences systematically studied the impact of natural ecosystem reclamation into farmland in arid areas on soil organic carbon storage and its driving mechanism
based on mixed effect model.

The results show that the soil organic carbon stock has changed significantly under the combination of land reclamation and farmland management (P<0.
05).

The amount of soil organic carbon after desert and shrubland reclamation with low soil organic carbon increased by 278.
86% (95% CI, 196.
43%–361.
29%) and 45.
38% (26.
53%–62.
23%), respectively, while the organic carbon stocks decreased by 24.
11% (18.
38%–29.
85%) and 10.
70% (1.
80%–19.
59%)
after forest and grassland reclamation for cultivated land.
For grasslands with low soil organic carbon storage, long-term fertilization after reclamation leads to an increase in
soil organic carbon storage.
At the same time, the response curve of soil organic carbon storage with the cultivation life is constructed, so as to provide a basis
for accurately assessing the impact of land reclamation on regional carbon storage.
The results are conducive to reducing the uncertainty of carbon dynamic estimation in arid areas and improving the scientific nature
of organic carbon sequestration strategies.

The results were published in Global Change Biology
under the title "Effects of land clearing for agriculture on soil organic carbon stocks in drylands: A meta-analysis.
" The first author of the paper is Wang Yuangang, a doctoral student at Xinjiang Institute of Bioscience, and the corresponding author is Luo Geping, researcher of Xinjiang Institute of Bioland and associate professor
Li Chaofan of Nanjing University of Information Science and Technology.
The research was supported
by the National Natural Science Foundation of China and the Xinjiang Natural Science Foundation Key Project.

Link to the article: https://doi.
org/10.
1111/gcb.
16481

Figure 1.
Effects of natural ecosystem reclamation for cropland on soil organic carbon stocks (95% confidence interval)

Figure 2.
Effects of initial soil organic carbon stocks (a), fertilization (b), planting of perennial crops (c), irrigation (d) and years of tillage (e) on changes in surface and subsurface soil organic carbon stocks after reclamation of natural ecosystems (95% confidence interval)

Figure 3.
Changes in soil organic carbon stocks with years of cultivation after reclamation of woodlands (a), grasslands (b), deserts (c) and shrublands (d) (95% confidence interval)