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Dynamics of soil organic carbon following land-use change:insights from stable C-isotope analysis in black soil of Northeast China

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Acta Geochimica 2018年第5期37卷 746-757页

作者： Chenglong Tu Congqiang Liu Timothy A.Quine Matthew william jones Taoze Liu Longbo Li Wenjing Liu State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Key Laboratory of Environmental Pollution Monitoring and Disease Control Ministry of Education Guizhou Medical University School of Geography College of Life and Environmental Sciences Hatherly Laboratory University of Exeter Key Laboratory of Shale Gas and Geoengineering Institute of Geology and Geophysics Chinese Academy of Sciences

Intensive soil tillage is a significant factor in soil organic matter decline in cultivated soils. Both cultivation abandonment and foregoing tillage have been encouraged in the past 30 years to reduce greenhouse gas emissions and soil erosion. However, the dynamic processes of soil organic carbon (SOC) in areas of either continuous cultivation or abandonment remain unclear and *** aims were to assess and model the dynamic processes of SOC under continuous tillage and after cultivation abandonment in the black soil of Northeast China. Soil profiles were collected of cultivated or abandoned land with cultivation history of 0–100 years. An isotope mass balance equation was used to calculate the proportion of SOC derived from corn debris (C_4) and from natural vegetation (C_3) to deduce the dynamic process. Approximately 40% of SOC in the natural surface soil (0–10 cm) was eroded in the first 5 years of cultivation, increasing to about 75% within 40 years, before a slow recovery. C_4 above 30 cm soil depth increased by 4.5%–5% or 0.11–0.12 g·kg^(-1) on average per year under continuous cultivation, while it decreased by approximately 0.34% annually in the surface soil after cultivation *** increase in the percentage of C_4 was fitted to a linear equation with given intercepts in the upper 30 cm of soil in cultivated land. A significant relationship between the change of C_4 and time was found only in the surface soil after abandonment of cultivation. These results demonstrate the loss and accumulation of corn-derived SOC in surface black soil of Northeast China under continuous tillage or cultivation abandonment.

关键词： C3 photosynthesis C4 photosynthesis Land-use change Stable carbon isotopes Black soil of Northeast China

Xi-Biden Meeting Helps to Bring *** Out of the Deep Freeze

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China Today 2022年第12期71卷 44-46页

作者： william jones the Chongyang Institute for Financial Studies at Renmin University of China

Covering nearly all the major concerns of the two sides,the cordial meeting between the presidents of China and the United States prior to the G20 Bali summit sent an uplifting signal to the world that the tension bet... 详细信息

关键词： tension probably Deep

A Testing Time for U.S.-China Relations

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China Today 2023年第2期72卷 30-32页

作者： william jones Chongyang Institute for Financial Studies at Renmin University of China

While the unipolar world is still orbiting in the sphere of influence of Anglo-American elite and some of their allies,the rest of the world is marching in a different *** year 2022 proved to be a turbulent one for U.... 详细信息

关键词： direction relations turbulent

Laying Out a Pathway for China and the World

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China Today 2022年第11期71卷 38-41页

作者： william jones the Chongyang Institute for Financial Studies at Renmin University of China

Setting out the agenda to transform China into a modern socialist society,the 20th CPC National Congress sent a clear message to the world that China will deepen and expand global partnerships based on equality,openne... 详细信息

关键词： equality expand socialist

A Message of Hope for a Stricken World

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China Today 2021年第6期70卷 44-45页

作者： william jones University of China

AN annual gathering of business people and government representatives from the Asia Pacific region and beyond each year at the Boao Forum for Asia in south China’s Hainan Island is always an occasion to gain fresh insights into economic development in the region and the rest of the *** taking the helm of the country,President Xi Jinping has addressed the forum’s annual conference multiple *** theme of this year’s conference is“A World in Change:Join Hands to Strengthen Global Governance and Advance Belt and Road Cooperation.”In the backdrop of the major tensions between China and the *** the economic disruption caused by the COVID-19 pandemic that has ravaged the world over the past year。

关键词： gathering Island World

The Fantasies of Nancy Pelosi and the Real World

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China Today 2022年第9期71卷 19-21页

作者： william jones Renmin University of China

Hubris manifest in the *** Speaker Nancy Pelosi and some congressmen about the Taiwan question has created a national *** America has lost in its search for global power,China has won through its commitment to the development of mankind.N ancient Greek mythology,the sin of hubris,or overbearing pride,was the greatest flaw in humans,leading often to their *** Icarus and his father Daedalus tried to escape the labyrinth on an island where they had been imprisoned by Minos,the King of Crete.

关键词： island Taiwan Nancy

Charting a Course for the Coming Years

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China Today 2021年第4期70卷 42-43页

作者： william jones U.S.publication Executive Intelligence Review

SHORTLY after the Spring Festival,China begins its annual“political season”with the convening of the Two Sessions,the session of the National People’s Congress(NPC)and that of the Chinese People’s Political Consultative Conference(CPPCC).This year both of these events have a very special ***,it will be the start of a new Five-Year Plan period,and secondly,this year marks the 100th anniversary of the founding of the Communist Party of *** will be the source of a great deal of celebration throughout the year.

关键词： Session Spring China.

Historic Achievements of the CPC

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China Today 2021年第7期70卷 30-32页

作者： william jones Chongyang Institute for Financial Studies under Renmin University of China

THE Communist Party of China(CPC)has every reason to take great pride in its historic accomplishments on the occasion of its 100th *** in 1921,despite the low number of individuals who were intent on pulling China out of the chaos following the downfall of the Qing Dynasty(1644-1911),while at the same time being hounded by the then authorities who suppressed everything that had a communist label,the leaders of the CPC had not been diverted from their mission,namely,improving the people’s livelihood and accomplishing the rejuvenation of the Chinese nation from the previous“century of humiliation.”

关键词： CPC accomplishment chaos

A New Vision for Global Challenges

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China Today 2020年第10期69卷 56-57页

作者： william jones the U.S.publication Executive Intelligence Review

VOLUME III of Xi Jinping:The Governance of China was published this year,with the release of new reports and speeches made by Chinese President Xi Jinping on numerous topics regarding China and the world from October ... 详细信息

关键词： release Global numerous