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羊草种群克隆分株之间光合产物的转移 被引量:12
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作者 王昱生 洪锐民 +4 位作者 黄大明 滕小华 李月树 盐见正卫 中村未树 《生态学报》 CAS CSCD 北大核心 2004年第5期900-907,共8页
羊草 (L eymuschinensis)是具有克隆生长习性的多年生根茎植物。其分株系统能存活 7a,其根茎甚至可在地上部分死亡后继续存活。羊草分株可分为 7个年龄 (AC) ,有 :AC0、AC1、AC2、AC3、AC4、AC5和 AC6 ;4个世代 ,即祖代开花分株世代 (G(... 羊草 (L eymuschinensis)是具有克隆生长习性的多年生根茎植物。其分株系统能存活 7a,其根茎甚至可在地上部分死亡后继续存活。羊草分株可分为 7个年龄 (AC) ,有 :AC0、AC1、AC2、AC3、AC4、AC5和 AC6 ;4个世代 ,即祖代开花分株世代 (G(1) )或祖代营养分株世代 (G1)、母代开花分株世代 (G(2 ) )或母代营养分株世代 (G2 )、当代开花分株世代 (G(3) )或当代营养分株世代 (G3)和子代营养分株世代 (G4 )。揭示了羊草克隆分株之间存在 3种光合产物的转移格局 ,它们是向项性转移、向基性转移和水平性转移。还观察到 ,不同类型分株可调节不同类型分株之间的光合产物转移量。对于向项性转移 ,光合产物主要输出到营养分株 (VR) ,以低转移速率输出到开花分株 (FR)。对于向基性转移 ,光合产物主要输出到 FR,而以低转移速率输出到 VR。对于水平性转移 ,该种转移出现在同一世代的姊妹分株 (SR)之间 ,在从 FR到 VR的转移或在从 VR到 FR的转移 ,转移速率较高 ,但在同种类型分株 (即从 FR到 FR或从 VR到 VR)之间的转移速率较低。幼嫩的 VR比同一世代的 展开更多
关键词 克隆植物 光合产物转移 资源转移格局
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对当前国际政治、经济格局多极化趋势中几个问题的看法 被引量:1
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作者 萧长春 《井冈山大学学报(社会科学版)》 1999年第3期63-69,共7页
当前国际政治、经济格局呈多极化的发展趋势,“一超多强”是多极化在现阶段的主要表现形式。多极化新格局不大可能以和平的方式实现,战争仍是合乎规律的选择。中国能成为多极中的“一极”,但其前进道路上存在许多隐患。
关键词 政治 经济格局 多极化 发展态势 格局转移 实现方式 隐患
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Changes of Wetland Landscape Pattern in New Coastal District of Tianjin City
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作者 杜林芳 冯仲科 +2 位作者 刘东云 唐雪海 吴根松 《Journal of Landscape Research》 2010年第3期17-22,共6页
With the wetland landscape in New Coastal District of Tianjin City as the chief study objective and based on the remote sensing and non-remote sensing data of ETM/TM with 1999-2007 as the time scale and the new admini... With the wetland landscape in New Coastal District of Tianjin City as the chief study objective and based on the remote sensing and non-remote sensing data of ETM/TM with 1999-2007 as the time scale and the new administrative region of New Coastal District as the space (scale) scope, this paper conducted the study on the landscape pattern change. The results showed that the natural wetland and agricultural land tended to decrease, while the saltern, maricultural areas and construction land increased apparently. The overall landscape shape tended to develop in simplification and regulation and with the development of population and social economy, human’s intervention to the landscape was getting improved. 展开更多
关键词 WETLAND Landscape pattern TRANSFER-MATRIX New Coastal District of Tianjin City
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China’s Industrial Upgrading and Value Chain Restructuring Under the New Development Pattern 被引量:21
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作者 Ni Hongfu Tian Ye 《China Economist》 2021年第5期72-102,共31页
Global industrial chains(GICs)have become a hallmark of the world economy underpinning the global production cycle.Since the reform and opening up was introduced in 1978,China has taken an active role in global value ... Global industrial chains(GICs)have become a hallmark of the world economy underpinning the global production cycle.Since the reform and opening up was introduced in 1978,China has taken an active role in global value chains(GVCs)and become the world’s factory floor.Under the external shocks to GICs,such as US trade frictions with China and the COVID-19 pandemic,China’s traditional comparative advantages in manufacturing which include its labor force and costs are waning.This has manifested in a wave of industrial relocations from China to other countries as well as China’s weakening international competitiveness.We took stock of the concepts and journey of GVCs and elaborated the intrinsic relationship between GVCs and the new development pattern of“dual circulations”.We also analyzed the trends of GVCs,the current status and problems of China’s industrial chains,and China’s market heft,complete industrial chains and the digital economy as new strengths for industrial chain upgrade.In our conclusion,this paper put forth some policy recommendations for China’s industrial chain upgrade in the context of dual circulations. 展开更多
关键词 industrial chains industrial relocation new development pattern GVCs
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The Key Driver of China’s New Economic Development Pattern:A Major Power’s Flying Geese Paradigm 被引量:1
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作者 Su Qingyi Wang Fenglong 《China Economist》 2021年第5期104-131,共28页
This paper examines China’s flying geese paradigm that serves as a key driver of a new pattern of the country’s economic development.Our results suggest that such a major power’s flying geese paradigm has taken sha... This paper examines China’s flying geese paradigm that serves as a key driver of a new pattern of the country’s economic development.Our results suggest that such a major power’s flying geese paradigm has taken shape in the aftermath of the global financial crisis in 2008.However,this paradigm has provincial heterogeneity in that industrial relocation varies across provinces.For instance,China’s central and western regions have shown differences while serving as destinations for labor-intensive industries and processing trade.This flying geese paradigm evolves in a slow and nonlinear manner,and may be subject to stagnation and even reversal. 展开更多
关键词 new economic development pattern flying geese paradigm industrial relocation labor-intensive industries processing trade
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