新たな研究が地域の砂漠化対策と生態系回復に科学的根拠を提供(New Study Adds Scientific Support for Regional Desertification Control, Eco-restoration)

2026-07-03 中国科学院(CAS)

中国科学院西北生態環境資源研究院の研究チームは、砂漠低木の年輪を利用した長期・高時間分解能の砂漠化復元手法を開発し、地域の砂漠化防止と生態系修復に向けた新たな科学的知見を示した。研究では、多様なリモートセンシングデータと砂漠低木の年輪年代学を組み合わせ、植生指数や砂漠化指数を統合した解析フレームワークを構築し、中国の騰格里砂漠とウランブハ砂漠に適用した。その結果、世界の陸地の43.09%が高リスクの砂漠化地域であり、主な要因は気候条件で、植生状態や土地管理がこれに続くことが明らかとなった。また、植生指数ではPerpendicular Vegetation Index(PVI:垂直植生指数)が乾燥地域の植生変化を最も安定して捉え、長期的な砂漠化復元に適した指標であることが確認された。さらに、ウランブハ砂漠北縁では砂漠化が改善傾向を示し、主に気候要因が支配的である一方、南縁では人間活動の影響が大きいことが判明した。本研究は、砂漠化の時空間変化とその要因解明を通じて、中国の「三北防護林計画」をはじめとする砂漠化対策や生態系修復の科学的基盤を提供する成果である。

<関連情報>

中国北西部ウランブー砂漠における過去140年間の砂漠化の時空間的変化と駆動メカニズム Spatiotemporal evolution and driving mechanisms of desertification in the Ulan Buh Desert, Northwest China, over the past 140 years

Yu Ren, Shengchun Xiao, Xiaomei Peng, Aijun Ding, Quanyan Tian, Jiakang Wang
Gondwana Research  Available online: 7 June 2026
DOI:https://doi.org/10.1016/j.gr.2026.05.004

新たな研究が地域の砂漠化対策と生態系回復に科学的根拠を提供(New Study Adds Scientific Support for Regional Desertification Control, Eco-restoration)

Highlights

  • A ∼140-year high-resolution desertification record for the Ulan Buh Desert (UBD) was reconstructed from shrub tree rings.
  • Desertification at both margins of UBD shows legacy effects and coherent 2–10-year variability.
  • In UBD, northern-margin desertification is climate-driven, while the southern margin is dominated by human activity.

Abstract

The United Nations Convention to Combat Desertification identifies Land Degradation Neutrality as a key 2030 Sustainable Development Goal, yet long-term, high-resolution desertification records are scarce in arid northern China. The Ulan Buh Desert (UBD), at the core of China’s wind–sand belt, is a major source of aeolian sediments entering the Yellow River, affecting ecological security and socioeconomic development across the basin and influencing windbreak–sand fixation systems in the Beijing–Tianjin region. Here, we reconstruct 140 years of desertification along the northern and southern margins of UBD using annually resolved shrub tree-ring records, overcoming the temporal limits of remote sensing and historical archives, and examine the underlying driving mechanisms. Desertification declined along the northern margin, while the southern margin remained relatively stable. Variability was marked by high-intensity phases in the mid-twentieth century and low-intensity conditions since the late 1980 s, with periods of divergence between margins. Both regions exhibited significant 2–10-year cyclical variability and pronounced legacy effects. Mechanistically, desertification along the northern margin was primarily associated with climatic factors, particularly drought severity and precipitation variability, whereas the southern margin was more strongly associated with human activity, with climate as a secondary factor. Teleconnected climate modes modulated desertification dynamics in a phase- and frequency-dependent manner. This study fills a critical gap in long-term, high-resolution desertification reconstructions in UBD and provides a robust foundation for regional mitigation and ecological restoration strategies.

 

低木年輪年代学により、騰格里砂漠における過去150年間の砂漠化の時空間パターンが明らかになった Shrub dendrochronology reveals the last 150 years of spatiotemporal patterns of desertification in the Tengger Desert

Yu Ren, Shengchun Xiao, Xiaomei Peng, Aijun Ding, Quanyan Tian, Jiakang Wang
Catena  Available online: 18 January 2026
DOI:https://doi.org/10.1016/j.catena.2026.109844

Highlights

  • PVI was identified as the most suitable vegetation index for reconstructing desertification processes based on shrub RWI.
  • A new framework for desertification reconstruction that integrates shrub ring-width indices, vegetation indices, and a desertification index was first presented.
  • Shrub ring-based reconstructions reveal significant spatiotemporal heterogeneity and diverse driving mechanisms of desertification processes in the Tengger Desert over the past 150 years.

Abstract

Desertification is among the most pressing ecological and environmental challenges worldwide, characterized by its long-term and complex dynamics. Long records are essential to reveal its historical evolution and underlying drivers, yet satellite-based monitoring spans only the past four decades, and reconstructions from historical documents, archaeology, or sediments often lack spatial representativeness and temporal precision. Here we take the Tengger Desert as a case study and develop an integrated framework that couples shrub ring-width indices (RWI) with multi-source remote sensing indices and a desertification index (DI). Using this approach, we reconstruct desertification in the desert’s peripheral zones since 1850 and investigate its drivers and cyclicity. Results show that desertification has generally weakened over the past 150 years: the northern (NTD), western (WTD), and southern (STD) margins exhibit declining trends, while the eastern margin (ETD) remains relatively stable. At the interannual scale, the reconstructed DI displays strong fluctuations, showing synchronous highs in 1972 and lows in 1978 across the four marginal zones; at the decadal scale, it reveals coherent phases, with synchronous periods in 1917–1920, 1926–1930, and 1978–1989. The dominant cycles of DI range from 2 to 10 years. NTD and WTD are controlled mainly by precipitation and drought, whereas human disturbance increasingly shapes STD and dominates ETD. Large-scale climate teleconnections modulate desertification variability, but their influence lacks consistency and persistence. Our findings provide a new framework for reconstructing long-term ecological change in arid deserts and offer scientific guidance for desertification control.

 

世界的な土地砂漠化リスク評価 Global land desertification risk assessment

Yu Ren, Shengchun Xiao, Xiaomei Peng, Bo Zhang, Jing Zhou, Jiakang Wang
Journal of Environmental Management  Available online: 26 November 2025
DOI:https://doi.org/10.1016/j.jenvman.2025.128098

Highlights

  • We conducted the first global assessment of desertification risk in 2020.
  • High to extreme desertification risk, including desert landscapes, affects 43.09 % of global land.
  • Climate quality is the primary driver of global desertification risk.

Abstract

Desertification ranks among the most pressing ecological and environmental challenges worldwide. Identifying high-risk desertification areas and understanding their main driving factors are critical to the realization of the United Nations Convention to Combat Desertification and the 2030 Sustainable Development Goals. However, the current understanding of global desertification risk and its main driving factors remains limited to local regions. Here, we used the enhanced Mediterranean Desertification and Land Use-Environmentally Sensitive Area (MEDALUS-ESA) model, which integrates multifaceted evaluation indicators from four aspects, to conduct an assessment of the global desertification risk in 2020. Our results found that 43.09 % of the global area is currently located in regions at high or extreme risk of desertification. Additionally, areas with low and moderate desertification risk are about 35.52 % and 21.39 %, respectively. Regions at high and extreme risk are mostly concentrated in the Mediterranean, East Africa, East Asia, South Africa, South America, and West Africa. Globally, climate quality emerged as the primary driver of desertification risk, followed by vegetation quality and management quality. At the same time, the contributions of these factors show significant variability with space. These insights can provide valuable guidance for managing desertification risk at global and regional scales.

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