Assessment of the World Largest Afforestation Program: Success, Failure, and Future Directions

Zhu, J. J.; Zheng, X.; Wang, G. G.; Wu, B. F.; Liu, S. R.; Yan, C. Z.; Li, Y.; Sun, Y. R.; Yan, Q. L.; Zeng, Y.; Lu, S. L.; Li, X. F.; Song, L. N.; Hu, Z. B.; Yang, K.; Yan, N. N.; Li, X. S.; Gao, T.; Zhang, J. X.; Ellison, A.

doi:10.1101/105619

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bioRxiv · 10.1101/105619

Assessment of the World Largest Afforestation Program: Success, Failure, and Future Directions

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Abstract

The Three-North Afforestation Program (TNAP), initiated in 1978 and scheduled to be completed in 2050, is the worlds largest afforestation project and covers 4.07 x 106 km2 (42.4%) of China. We systematically assessed goals and outcomes of the first 30 years of the TNAP using high-resolution remote sensing and ground survey data. With almost 23 billion dollars invested between 1978 and 2008, the forested area within the TNAP region increased by 1.20 x 107 ha, but the proportion of high quality forests declined by 15.8%. The establishment of shelterbelts improved crop yield by 1.7%, much lower than the 5.9% expected once all crop fields are fully protected by shelterbelts. The area subjected to soil erosion by water decreased by 36.0% from 6.72 x 107 to 4.27 x 107 ha; the largest reductions occurred in areas where soil erosion had been most severe and forests contributed more than half of this improvement. Desertification area increased from 1978 to 2000 but decreased from 2000 to 2008; the 30-year net reduction was 13.0% (4.05x106 ha), with 8.0% being accounted for by afforestation in areas with only slight, prior desertification. In addition to its direct impacts, the TNAP has enhanced peoples awareness of environmental protection and attracted consistent attention and long-term commitment from the Chinese government to the restoration and protection of fragile ecosystems in the vast Three-North region. The significant decline in forest quality, limited success in reducing desertification, and low coverage of shelterbelts are aspects of the TNAP in need of re-assessment, and additional ca. 34 billion dollars will be needed to ensure the completion of the TNAP.

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Zhu, J. J., Zheng, X., Wang, G. G., Wu, B. F., Liu, S. R., Yan, C. Z., Li, Y., Sun, Y. R., Yan, Q. L., Zeng, Y., Lu, S. L., Li, X. F., Song, L. N., Hu, Z. B., Yang, K., Yan, N. N., Li, X. S., Gao, T., Zhang, J. X., Ellison, A.. 2017-02-03. Assessment of the World Largest Afforestation Program: Success, Failure, and Future Directions. https://doi.org/10.1101/105619

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