Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： As green and low-carbon transition has gained world-wide recognition and become the inherent requirement of fully building a modern socialist China, the consumption of critical metals will increase drastically in the next decades. Meanwhile, this will mean a continually increasing potential of critical metals recycling. Facing changes and pandemic unseen in a century and increasing geopolitical conflicts, it has become a strategic consensus on the national security level for Western countries like the United States and Europe Union to acknowledge and enhance the role of recycling in secure provision of critical metals. Here, in this article, we have discussed the future potentials and major challenges of critical metals recycling and reviewed the strategies proposed by the main industrialized countries. Based on this, we aim to help formulate China’s national strategies and countermeasures regarding critical metals recycling and thus contribute to supporting the achievement of China’s “dual carbon” ambition and its green and low-carbon transition in the next decades.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Food system is the foundation of human society, thus the sustainable transition of food system is one of the key topics towards global sustainability. Facing the global climate crisis, regional conflict, and pandemic that unseen in a century, it becomes critical to build a sustainable food system in line with the Chinese context for ensuring its grain and food security, national nutrition and health, social justice, ecological balance, market effectiveness, and system resilience. To address these focuses, this study analyzed the main issues and challenges faced by China’s current food system, and decoded the relationship between food system and sustainable development goals of the United Nations from supply, demand, and security guarantee mechanism perspectives. Based on these, this study developed a conceptual framework for sustainable food system from life cycle, global, and system perspectives. This study further identified six key dimensions, including security, health, justice, greenness, economy, and resilience, for constructing the strategic framework of China’s sustainable food system, and proposed paths ahead for implementation. We hope to provide some system reflections on how to ensure China’s food security in the new era and further to contribute to sustainable global food system transition with Chinese wisdom and Chinese solutions.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： As the “water tower” of Asia, the Tibetan Plateau provides basic water resources for the regional ecosystems. Among the variety of water resources, natural precipitation is most relevant to ecosystems, and temperature also affects soil moisture availability by regulating evapotranspiration, thus affecting ecosystem process. From the aspects of community composition and structure, vegetation phenology, coverage and productivity, and water conservation function by ecosystems, this paper reviewed the series of impacts caused by changed water resources on the Tibetan Plateau ecosystems in recent years, and the underlying mechanism was further revealed. The shifted water conditions led to changes in community coverage, species diversity, and relative importance of each species, thereby driving community succession. The strengthened preseason precipitation advanced spring phenology, and postponed autumn phenology. The preseason precipitation also adjusted the responses of vegetation phenology to temperature. Under global changes, the vegetation coverage increased and ecosystem productivity strengthened on the Tibetan Plateau, but with high spatial heterogeneities. The incongruous changes of temperature and precipitation complicated their effects on vegetation, as exhibited by their distinct relative determination effects in different areas. Water conservation by ecosystems stems from interactions among soil-vegetation-atmosphere, which is influenced by climate, vegetation, soil, human activities, etc. The future studies need to pay mounting attentions to the coupling effects of climates and vegetation cover on water conservation of ecosystems, and also attribute the separate contribution from each factor.
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-11-20 Cooperative journals: 《干旱区地理》
Abstract：演化经济地理学认为，地方产业演化是路径依赖的，新的产业从本地现有关联产业中衍生出 来。这个理论以地方具备同等优势的创造能力为前提，而创造能力本身对地方条件有着较高的要求。现实条件下，发展中地区开发先进工业，相比依赖本地现有产业基础自主创造的发展路径，紧密跟随并积极参与发达经济体开辟的先进制造业产品市场、主动吸收知识溢出、进行学习合作型创造或是一条更可行的道路。以2000—2015年中国561个海关报关国内地区代码划分的地区行政单元高技术出口产业地理演化为研究对象，验证了这一假设。结论显示：本地技术关联水平对地方高技术产业地理演化主要在近期产生影响，进口产品的知识溢出表现出中长期的促进作用，且地方技术水平的差异对地方利用知识溢出效果并无显著影响。这一结论证明发展中地区可以通过紧随前沿、学习合作打破本地路径锁定，实现路径跳跃。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2019-06-14 Cooperative journals: 《干旱区地理》
Abstract：在我国经济进入新常态发展阶段的背景下，经济开发区的空间布局优化和主导产业转型升级事关区域经济协同发展、创新驱动发展和高质量发展。本文选取西北五省区作为研究对象，根据官方发布的国家级和省级开发区数据，利用核密度分析和多距离空间聚类分析等方法探讨该区域经济开发区2006年和2017年空间格局演变及主导产业变迁过程，得到以下结论：（1） 2006年和2017年西北五省区经济技术开发区均呈现明显的空间集聚，集聚强度增大，并呈现差异化的集聚扩散模式。（2） 五省区开发区在特定范围内的空间分析尺度上显著集聚，2006—2017年间集聚程度和强度有不同程度的提高。（3） 五省区开发区整体产业结构并没有发生根本性变化，但主导产业为战略性新兴产业的经济开发区数量和所占比例均有较大幅度的提升，不同类型主导产业的开发区在空间上呈现明显的变迁差异：技术密集型产业更倾向于在“西安—兰州—银川”集聚片区集聚；劳动密集型产业一方面在“乌昌石—奎屯—喀什”沿边集聚带强化集聚，另一方面，在“西安—兰州—银川”集聚片区的集聚中心逐步从兰州转移到了西安地区；资金密集型产业在新疆“乌昌石—奎屯—喀什”沿边集聚带和西安市与兰州市之间的“通道状”集聚区强化集聚；战略性新兴产业为主导的开发区在西安市和乌鲁木齐市集聚。
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