Key Takeaways & Executive Findings
- •• • High-cold mining regions experience freeze-thaw cycles exceeding 100 times annually, leading to soil structure destruction and erosion rates significantly higher than low-altitude mines; for example, in Qinghai Muli and Gansu Subei, soil erosion modulus is markedly elevated, necessitating restoration strategies that prioritize soil stabilization and structure improvement. • • Wind erosion in high-cold mine dumps (e.g., Zhaha'naoer and Huolinhe) causes fine soil loss rates 2-4 times that of natural grasslands, resulting in surface crusting and reduced water infiltration; thus, effective restoration must address wind erosion control and soil hydraulic conductivity. • • Regional degradation characteristics vary: high-cold grassland areas (e.g., Xilingol, Huolinhe) suffer from strong wind erosion and frequent freeze-thaw, while arid/semi-arid areas (e.g., Ordos) face desertification and salinization, and northwest Gobi areas (e.g., Hami) experience extreme drought and difficult biological soil crust reconstruction, requiring region-specific restoration approaches. • • The proposed progressive restoration framework sets short-term goals for soil stability and structure improvement, medium-term goals for multifunctional plant-soil community construction, and long-term goals for self-sustaining ecosystems, emphasizing the need for adaptive management and monitoring over extended periods.
Abstract
Open-pit mining in high-cold regions causes severe ecological degradation, including vegetation loss, soil structure destruction, and frequent freeze-thaw disturbances, complicating ecosystem recovery. This review systematically synthesizes the current status, theories, and key restoration technologies for degraded ecosystems in high-cold mining areas. Comparative analysis with typical high-cold degraded ecosystems worldwide reveals that high-cold mining areas face challenges such as frequent freeze-thaw cycles, hydrological disruption, wind erosion, and difficult vegetation establishment. We propose strengthening aboveground-belowground synergistic restoration: (1) aboveground restoration should focus on screening cold-resistant native plants and optimizing mixed community configurations, combined with plant growth-promoting multi-microbial consortia to facilitate vegetation recovery; (2) belowground restoration should be based on engineering soil profile reconstruction, integrating physical-chemical-biological multi-dimensional remediation techniques to achieve aboveground and belowground community reconstruction and functional recovery; (3) a progressive restoration framework is established, with short-term goals targeting soil stabilization and structure improvement, medium-term goals focusing on constructing multifunctional plant-soil communities, and long-term goals achieving self-sustaining, maintenance-free restored ecosystems. Finally, addressing the unclear mechanisms of aboveground-belowground synergistic interactions and insufficient environmental adaptability of restoration technologies, two prospects are proposed: (1) deepening research on aboveground-belowground synergistic mechanisms to reveal interactions between cold-tolerant microorganisms and plants; (2) advancing the development of characteristic restoration technologies adapted to high-cold environments.
1. Introduction
Open-pit mining in high-cold regions, characterized by altitudes above 2,500 m and annual average temperatures below 5°C, induces severe ecological degradation through topsoil stripping and vegetation removal, leading to soil structure destruction, nutrient loss, and microbial community disruption. The unique combination of low temperatures, frequent freeze-thaw cycles, and strong wind erosion in these areas severely inhibits natural recovery processes, rendering conventional restoration techniques inadequate. Traditional single-dimensional approaches, focusing solely on aboveground vegetation or soil amendment, fail to address the complex aboveground-belowground interactions that drive ecosystem function, resulting in limited restoration success and long recovery times.
This review addresses the critical bottleneck by synthesizing current knowledge on aboveground-belowground synergistic restoration principles and technologies. It emphasizes the need for integrated strategies that couple cold-resistant plant selection and microbial consortia with soil profile reconstruction and multi-dimensional remediation. By analyzing regional degradation characteristics and existing restoration case studies, we propose a progressive framework that aligns short-term soil stabilization with long-term self-sustaining ecosystem development. This approach aims to overcome the limitations of existing methods and provide a scientific basis for effective and sustainable restoration of degraded ecosystems in high-cold mining areas.
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ZHANG Naili, YU Tongrui, LI Xingxuan, XU Changyou, LIU Yongjie, QU Laiye (2026). Research Progress and Prospects of Aboveground-Belowground Synergistic Restoration Principles and Technologies for Degraded Ecosystems in Open-Pit Mines in High-Cold Regions. Chinese Journal of Environmental Engineering. https://doi.org/10.12030/j.cjee.202505108
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Frequently Asked Questions
What are the primary environmental stressors that hinder vegetation establishment in high-cold mine spoils, and how do they quantitatively impact restoration success?
Primary stressors include frequent freeze-thaw cycles (over 100 times annually), strong wind erosion (fine soil loss 2-4 times that of natural grasslands), and water scarcity. These factors lead to soil structure degradation, reduced water infiltration, and seed bank depletion, resulting in low germination rates and poor plant survival. Restoration success is thus contingent on mitigating these stressors through soil stabilization and water management.
How does the proposed aboveground-belowground synergistic restoration approach differ from traditional methods, and what specific techniques are recommended for soil reconstruction?
Traditional methods often focus on single measures like vegetation planting or soil amendment, neglecting the interactions between plants, soil, and microbes. The synergistic approach integrates cold-resistant native plant selection with multi-microbial consortia to enhance nutrient cycling and soil structure. For soil reconstruction, it recommends engineering-based profile reconstruction combined with physical (e.g., amendments), chemical (e.g., pH adjustment), and biological (e.g., microbial inoculation) techniques to restore soil functionality.
What are the key regional differences in degradation characteristics among high-cold mining areas in China, and how do they influence restoration strategies?
Regional differences are significant: high-cold grassland areas (e.g., Xilingol, Huolinhe) face severe wind erosion and freeze-thaw, requiring windbreaks and soil stabilizers; arid/semi-arid areas (e.g., Ordos) suffer from water scarcity and salinization, necessitating drought-tolerant species and water-efficient irrigation; northwest Gobi areas (e.g., Hami) have extreme drought and poor soil, demanding specialized soil amendments and biological crust reconstruction. Restoration strategies must be tailored to these specific conditions.
What are the long-term goals of the progressive restoration framework, and how can self-sustaining ecosystems be achieved in high-cold mine sites?
The long-term goal is to achieve self-sustaining, maintenance-free ecosystems. This requires establishing multifunctional plant-soil communities that can naturally regenerate and maintain soil fertility. Strategies include promoting native species diversity, enhancing soil organic matter, and fostering beneficial microbial communities. Monitoring and adaptive management are essential to ensure ecosystem resilience and functionality over time.
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