Global Environmental Change and National Security of China

The concept of security has been redefined since the 1990s. As one of the important factors threatening human security, global environmental change has become a new challenge to the national security and social development. The national security problems caused by global environmental change, on one hand, are closely related to the global environmental problems, and, on the other hand, are manifested in the conflicts of international affairs. The global environmental change severely challenges the future de...     

电解锰产业集聚区河流锰污染演变趋势和时空分布特征

松桃河流域是我国锰产业最为集中的区域之一,资源开发和利用形成的污染严重.通过对松桃河电解锰产业集聚区流域2015-2019年的8个典型断面的总锰监测数据的分析,用秩相关系数法探究了河流锰污染总体变化趋势,并用系统聚类分析法分析了河流锰的时空分布特征,结合聚类结果对污染趋势做进一步分析.秩相关系数分析结果表明,近年来松桃...     

Multi-stage evolution of social response to flood/drought in the North China Plain during 1644–1911

How the past human society responded to climatic disasters could provide better understanding on the nature of climate–human–ecosystem interactions and the knowledge of the vulnerability for the society in the context of changing climate. In this paper, the North China Plain in the Qing dynasty (1644–1911) is selected as a typical regional social-ecological system; with historical information kept in official documents, social responsive behavior and measures to flood/drought (e.g., reclamation, disaster relief, migration, revolt) are quantitatively described with proxy indicator time-series. It is found that the dominant responsive strategy altered significantly in different stages: (1) stage of cropland expansion (1644–1720); (2) stage of governmental disaster relief (1721–1780); (3) stage of increasing climate refugees (1781–1860); (4) stage of revolt and emigration (1861–1911). The multi-stage evolution of social response was impacted by various natural and social factors: (1) regional population–food balance and governmental finance were the most important limiting factors; (2) the interaction between the governmental policy and refugees’ behavior in disasters affected the social consequences to a certain extent; (3) decadal-to-multi-decadal climate change would also impact the social response measures, even directly trigger the shift of dominant responsive strategy. This study would be helpful for deeper understanding of social resilience and better responding to climate change and extreme events in the present and future.     

Vegetation of Northeast China during the late seventeenth to early twentieth century as revealed by historical documents

Historical vegetation antedates current anthropogenic land use. It can therefore be used to reveal land use/cover changes due to human activities. We collected 197 records from Chinese historical documents, including gazettes, government files, private literature, and travel notes, to reveal vegetation status during the late seventeenth century to early twentieth century across Northeast China. The results indicate that woodland and grassland were the dominant landscapes, whereas swamps accounted for a small area. Woodland was composed of needleleaf deciduous forest, broadleaf deciduous forest, and mixed needleleaf and broadleaf forest. Mixed forest occupied the largest area. This forest type covered most of the Greater Khingan Range, Lesser Khingan Range, and Changbai Mountains. Grassland occupied the Songnen Plain, Liao River Plain, and Inner Mongolia Plateau, whereas swamps covered nearly the entire Sanjiang Plain. In addition, the data revealed that most current cropland was converted from grassland in the Northeast Plain, whereas a small area of cropland was converted from woodland and swamp.     

Impacts of inter-sectoral trade on carbon emissions—a case of China in 2007

With the increase in international trade, more attention has been given to quantifying the impacts of international trade on energy use and carbon emissions. Input-output analysis is a suitable tool for assessing resources or pollutants embodied in trade and it has become a critical tool for performing such analysis. This study estimated the national and sectoral carbon emissions embodied in Chinese international trade using the latest available China input-output table of 2007. The results showed that a significant exporting behavior of embodied carbon emissions existed in China??s trade. Over 1/3 of the emissions in Chinese domestic production processes were generated for exports in 2007. The net balance of emissions embodied in exports and imports accounted for nearly 30% of China??s domestic emissions, which means that any policy made to increase the exports would result in a significant growth of China??s domestic emissions. Since over half of China??s export trade is processing trade, the re-exported emissions could not be overlooked; otherwise, it would hard to capture the actual emissions generated abroad to obtain China??s domestic consumption. The enlargement of export scale is a primary driven factor to the rapid growth of China??s exported emissions. It is necessary for China to adjust its economic and industrial structure to reduce the dependence of economic growth on the export trade. However, when adjusting industry structures or making policies on carbon emission reduction, it will be more reasonable to consider the relationship between production and consumption, rather than just focus on the emission values of sectors?? direct production, as a large part of carbon emissions emitted by the principal direct polluters were generated to obtain the products which were required by other sectors.