Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： China is a large mountainous country in the world, where the mountainous area is about two-thirds of the land area. In the past ten years, the coverage rate of mountain forest and grass vegetation has increased by 8.2%, the average value of mountain green coverage index has reached 82.1%, and vegetation coverage has reached the highest value since the founding of the People’s Republic of China; The area of water and soil erosion has decreased by 275 000 square kilometers, and the annual soil erosion in mountainous areas has decreased by 27%. At present, the backbone system of mountain ecological security barrier in China has basically formed, and an efficient mountain disaster prevention and control system has been continuously improved, remarkable results have been achieved in mountain disaster reduction. At the same time, a historic accomplishment has been achieved in poverty alleviation of mountainous areas, the industrial structure in mountainous areas has been significantly optimized, and the modernization process has steadily advanced.
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 upstream region accounts for 55.4%, 33.2%, and 23.3% of the area, population, and GDP of the Yangtze River Economic Belt respectively. The level of high-quality development of the upstream region is closely associated with the success or failure of the national strategic objectives of the Yangtze River Economic Belt. Through analyzing the important role of the upstream area in maintaining the lifeline of the Yangtze River, ensuring the supply of strategic resources, maintaining the ecological base, strengthening spatial connections, and expanding the consumer market, authors summarize the tough challenges faced by the upstream region, such as traditional path dependence, polarization of urban structure, regional disparity, low green-capital conversion, and inadequate development quality. In the process of promoting the goal of high-quality development in the upstream region, we argue that it is an important strategy to build a multi-scale adaptation system for land space, to narrow the sharp differentiation between the first and the last grades of urban system, to fill in the depression on the edge of Chengdu-Chongqing Economic Circle, to clarify the economic categories based on ecological capital, and to bridge an cooperation mechanism between mainstream and tributaries for highquality development.
Subjects: Geosciences >> Geology submitted time 2020-03-26
Abstract： "
Peer Review Status:
Awaiting Review
Subjects: Geosciences >> Geology submitted time 2020-03-26
Abstract： " "
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Geochemistry submitted time 2020-03-26
Abstract： Water-rock (soil) chemical interaction (CWRI) is of special significance in the formation process of rainfall induced landslide. On the one hand, rain erosion will cause damage to rock and soil mass, on the other hand, it will generate a large number of secondary clay minerals. The main reason for the formation of the sliding surface is the decrease of the shear strength of the sliding surface caused by the corrosion damage and the enrichment of secondary clay minerals in the sliding surface. In this paper, a high pressure open flow system is used to simulate the chemo-mechanical environment of the sliding surface. Taking calcite and montmorillonite as examples, the rate and controlling factors of the dissolution reaction of the minerals on the sliding surface are studied, so as to reveal the formation mechanism of the sliding surface and its chemo-mechanical process. The results show that: 1) the dissolution rate of minerals increases with the increase of pressure, but the response of different minerals to pressure is different; 2) with the decrease of pH value of solution, the H + activity increases gradually, and the dissolution rate of minerals increases significantly; 3) the flow rate effect of mineral dissolution is very complex, which is related to pressure, pH and mineral species; 4) the dissolution of minerals does not meet the stoichiometric relationship. The above experimental results show that the dissolution on the sliding surface is closely related to the damage of soil and the evolution of the strength of the sliding surface. The depth of the sliding surface, the types of minerals and the acidity and alkalinity of groundwater jointly determine the dissolution rate and transformation characteristics of the minerals on the sliding surface. The increase of the depth of the sliding surface or the increase of the soluble minerals accelerates the formation of the sliding surface. The increase of the acidity of groundwater will accelerate the water rock reaction rate, and thus accelerate the decrease of the strength of the sliding surface.
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-09 Cooperative journals: 《干旱区研究》
Abstract：干旱是柯西河流域中山区发生最为频繁的气象灾害之一，对农业生产造成极大的影响。利用气象、农业数据，结合线性趋势、回归分析等方法，分析了1998—2015年研究区的干旱变化特征及其对作物单产增长率的影响。结果表明：① 研究区作物缺水指数呈先上升后下降的趋势，就作物缺水程度来看，南部干旱灾害最为严重，中部其次，北部最轻；② 干旱对不同作物产量的影响差异显著。当0.60≤CWSI（作物缺水指数）<0.63时，小麦单产增长率受到干旱的影响；当0.63≤CWSI＜0.64时，马铃薯和小麦受到干旱影响；当0.64≤CWSI＜0.65时，大麦、马铃薯和小麦受到干旱影响；当0.65≤CWSI＜0.66时，玉米、大麦、马铃薯和小麦受到干旱影响；当CWSI≥0.66时，玉米、大麦、马铃薯、小麦和水稻等5种作物均受到干旱影响；③ 干旱对作物产量的影响存在显著的区域差异，不同地区的作物受干旱影响的临界值和程度不同。
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