Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Strategic and critical minerals are a type of resource that is essential to the country’s economic development, indispensable to strategic emerging industries, and closely related to geopolitics. The types of strategic and critical minerals show some laws of spatial-temporal evolution due to the different stages of national economic development, economic structure and global industrial division of labor. Especially since the new century, with the rapid development of strategic emerging industries such as information technology, artificial intelligence and renewable energy, the connotation of strategic critical minerals has been continuously extended and closely connected with the industrial chain, highlighting its important position and security significance. China, the United States and the European Union have a high degree of overlap in the types of strategic critical minerals, and the United States and Western countries are trying to build a critical mineral supply chain independent of China. Hence, it requires China to formulate relevant strategies and make scientific and reasonable responses.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Beijing-Tianjin-Hebei region, Yangtze River Delta, and Guangdong-Hong Kong-Macao Greater Bay Area are the three largest urban agglomerations in China, and have been increasingly becoming the core engines of China’s economic growth. Nevertheless, rapid regional urbanization accompanying high-intensity human activities has also brought enormous social and environmental pressure in these urban agglomerations, posing a grand challenge to urban and regional sustainability. This study conducts a cross-urban agglomeration comparison of the ecological and environmental changes over the past two decades. Using a combination of remotely sensed data, in-situ monitoring data, and environmental statistic data, the changes in four dimensions are quantified, namely ecological quality, environmental quality, resource and energy use efficiency, and eco-environmental governance capacity. Further, the effectiveness of environmental policies and initiatives is evaluated at the national and urban agglomeration levels. It is found that the quality of ecological land has increased steadily since 2000, with increased provision of ecosystem services. Air quality and water quality have been substantially improved, and the use of resources and energy efficiency have been greatly improved. The pollution emissions per unit GDP have been greatly reduced. The ecological and environmental infrastructures have become increasingly available, along with gradually strengthened governance capacity on environmental protection and ecological restoration. The National 10th to 13th Five-Year Plan for Environmental Protection played a significant role in environmental protection and ecological restoration across mega urban agglomerations. The environmental challenges, of urban agglomerations faced now and in the future, are also discussed, so as to the policies and actions that need to be addressed.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The 20th Party Congress made a significant proposal: “advance the Beautiful China Initiative and take a holistic and systematic approach to the conservation and improvement of mountains, waters, forests, farmlands, grasslands, and deserts”. Thees tablishment of a sustainable national economy and ecological civilization is a major priority for the Guangdong-Hong Kong-Macao Greater Bay Area (GBA). The GBA’s current land development and protection situation is briefly summarized in the study, which also analyzes the issues with ecological protection and restoration in terms of whole-factor chain management, cross-regional cooperation, and target patterns. From the viewpoints of the system view, holistic view, synergy view, and the study makes pertinent recommendations. The study’s goal is to promote the modernization of the GBA so that people and nature can live harmoniously.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Qinghai-Tibet Plateau is important ecological security barrier of China and even Asia, and one of biodiversity conservation hotspots. Ensuring ecological security and protecting biodiversity are key tasks of ecological protection in Qinghai-Tibet Plateau. In Qinghai-Tibet Plateau, wildlife is very rich but there are many threatened species. During past 15 years, ecosystem pattern is stable, and ecosystem quality generally elevates in Qinghai-Tibet Plateau. Correspondingly, water retention, soil retention, and sandstorm prevention are improved and the trend of ecological degradation is suppressed. The construction of natural reserves and the implementation of ecological protection projects in Qinghai-Tibet Plateau contribute to the improvement of ecological security barrier function. However, due to the impacts of warm-wet tendency and human activities, Qinghai-Tibet Plateau is facing a series of ecological degradation risks, including frozen soil area withering, marsh reduction, wildlife habitat degradation, alien invasion, and ecosystem degradation. To further protect Qinghai-Tibet Plateau’s ecological security barrier, the following measures could be taken, namely, optimizing spatial pattern of natural protected area, establishing natural protected area system mainly based on national park group, and implementing ecological protection and restoration projects.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The coupled Human-Natural System thinking is considered as an important theoretical basis for territorial ecological restoration. The relationships between ecological space, production space, and living space show three evolution stages in territorial governance: coordinated arrangement, systematic governance, and human-nature harmony. In this regard, coupled Human-Natural System research is necessary to set the perspectives of coupling indicators, coupling hierarchies, coupling effects and coupling models to identify the primary evaluation indicators, delineate hierarchical nested regions, decouple the spatio-temporal relationship of social#2;ecological effects, and develop human-natural coupling models, so as to systematically support the territorial ecological restoration and facilitate the national and regional high-quality development.
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-06-22 Cooperative journals: 《干旱区研究》
Abstract：降水是干旱半旱地区土壤水分的主要来源，对该区植被恢复具有重要意义。本文采用EC-5土壤水分传感器对2014—2015年0~120 cm土壤水分进行连续监测，研究了退耕后不同恢复年限草地土壤水分动态变化及其0~40 cm土壤10 min时间尺度土壤水分对降水的响应。结果表明：土壤水分从恢复5 a草地向恢复15 a草地逐渐降低，这种降低趋势在恢复30 a草地减弱。恢复5 a草地土壤水分增幅最小，响应次数最少。单次降雨事件中，土壤水分增长过程和衰减过程均符合Logistic模型。恢复5 a草地相对稳定期(平台期)历时最长；恢复15 a草地土壤水分在表层(0~5，5~10 cm)增速最快，而在下层(20~40 cm)增速减慢且响应时间滞后；恢复30 a草地在下层(20~40 cm)增速最快。建议对恢复草地应适当采取措施，促进降雨向深层土壤水分转化，并减少恢复初期平台期历时。
Subjects: Geosciences >> Geography submitted time 2018-01-11 Cooperative journals: 《智库理论与实践》
Abstract：[目的/意义] 针对新世纪我国土壤污染凸显的严峻形势，探索能有效改善土壤质量、保护土壤环境和安全利用土地资源的战略机制，对保障农产品质量安全和公众健康、实现土地可持续利用和推动生态文明建设具有重要的现实意义和深远的战略影响。[方法/过程] 本文系统分析了我国土壤污染防治过程中面临的主要问题及挑战，并从土壤环境保护和土地安全利用的宏观视角定位土壤污染防治的关键举措。[结果/结论] 研究发现，我国土壤污染防治工作以农田和工业用地为治理重点，虽已在多方面取得重大进展，但仍存在以下主要问题：（1）针对农田污染，存在污染物空间异质性强、土壤污染与农产品超标差异大、土壤污染源头管控不到位和农田安全利用困难等问题；（2）针对工业污染地块，存在污染防治的政策法规体系不完善、技术能力建设滞后、片面强调工程修复和修复模式不持续等问题。为保护国家土壤生态安全，促进土地安全利用战略规划，应加快完善土壤污染防治顶层设计，系统开展源头治理、精准治理与综合治理，坚持“可持续修复、适度修复和绿色修复”原则，加强产业链中各利益方的密切合作，开拓多元稳定的土壤修复筹融资渠道，建立土壤环境质量预警机制。
Subjects: Library Science，Information Science >> Information Science submitted time 2017-07-13 Cooperative journals: 《智库理论与实践》
Abstract：[目的 /意义]自进入新世纪以来,持续高速经济增长、快速城镇化、资源高强度开发,以及汶川特大地震等自然灾害对生态系统带来巨大冲击和影响,这一时期也是我国生态保护与建设力度最大的时期,先后实施一系列生态保护政策与建设工程,促进了生态系统恢复,研究新时期生态问题特征及变化趋势,分析生态保护面临的问题,对完善生态保护政策与措施具有重要意义。[方法 /过程]分析我国2000—2010年主要生态问题及其变化趋势。[结果 /结论]研究发现,新世纪以来,我国生态问题开始进入转型期,农业导致的生态问题仍然严重,但开始好转;城市化导致的生态问题加剧,主要表现为:生态系统质量和服务功能低下,水土流失、土地沙化、石...
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