The covered-ice breakup in subarctic to arctic rivers in the early snowmelt season often gives any damage to instruments monitoring physical and chemical factors of water. The serious condition has brought few time se...The covered-ice breakup in subarctic to arctic rivers in the early snowmelt season often gives any damage to instruments monitoring physical and chemical factors of water. The serious condition has brought few time series data during the snowmelt runoff except the river stage or discharge. In this study, the contribution of snowmelt runoff to the discharge and sediment load is quantified by monitoring water turbidity and temperature at the lowest gauging station of U. S. Geological Survey in the Yukon River, Alaska, for more than 3 years (June 2006 to September 2009). The turbidity was recorded by a self-recording turbidimeter with a sensor of infrared-ray back-scattering type, of which the window is cleaned by a wiper just before a measurement. The turbidity time series, coupled with frequent river water sampling at mid-channel, produce time series of suspended sediment (SS) concentration, particulate organic carbon (POC) concentration and particulate organic nitrogen (PON) concentration (mg?L–1) by using the high correlation (R2 = 0.747 to 0.790;P 11 to 2.01 × 1011 m3), 8.7% - 22.5% of the annual sediment load (3.94 × 107 to 5.08 × 107 ton), 11.6% - 23.7% of the annual POC flux (4.05 × 105 to 4.77 × 105 ton), and 10.3% - 24.5% of the annual PON flux (2.80 × 104 to 3.44 × 104 ton). In the snowmelt season, the peak suspended sediment concentration preceded the peak discharge by a few days. This probably results from the fluvial sediment erosion in the river channels.展开更多
Biogeochemical feedback processes between soil organic carbon (SOC) in high-latitude organic soils and climate change is of great concern for projecting future climate. More accurate models of the SOC stock and its dy...Biogeochemical feedback processes between soil organic carbon (SOC) in high-latitude organic soils and climate change is of great concern for projecting future climate. More accurate models of the SOC stock and its dynamics in organic soil are of increasing importance. As a first step toward creating a soil model that accurately represents SOC dynamics, we have created the Physical and Biogeochemical Soil Dynamics Model (PB-SDM) that couples a land surface model with a SOC dynamics model to simulate the feedback cycle of SOC accumulation and thermal hydrological dynamics of high-latitude soils. The model successfully simulated soil temperatures for observed data from a boreal forest near Fairbanks, and 2000 year simulations indicated that the effect of the feedback cycle of SOC accumulation on soil thickness would result in a significant differences in the amount of SOC.展开更多
许多学者指出,不平等和社会资本不足等社会问题是以效率为导向的新自由主义发展战略的局限性。在此背景下,韩国文在寅政府强调社会价值是国家的核心价值。因此,公共机构须优先考虑社会价值。抛开意识形态上的讨论,这些社会和政策上的变...许多学者指出,不平等和社会资本不足等社会问题是以效率为导向的新自由主义发展战略的局限性。在此背景下,韩国文在寅政府强调社会价值是国家的核心价值。因此,公共机构须优先考虑社会价值。抛开意识形态上的讨论,这些社会和政策上的变化表明需要就如何切实实现社会价值进行具体探讨。公共机构已强化自身社会责任,为地方社区和低收入群体作出贡献。然而,企业往往将社会责任视为阻碍发展的诱因。公共企业作为一种公共机构,具有公司的特点,同时其实现盈利或企业家精神的内在目标可能会受到提升公共性来实现社会价值的限制。因此,公共企业面临着需兼顾社会及商业价值两方面以实现社会价值的挑战。为制定既能提升公共性以实现社会价值,又能确保盈利性的措施,本研究的重点是兼顾公司和社会层面的“创造共享价值(Creating Shared Value,CSV)”。本文探讨了公共企业追求的公共性和盈利性价值,并将企业社会责任(Corporate Social Responsibility,CSR)同创造共享价值进行了比较,旨在使两者都受益。本研究从创造共享价值的角度,以公共企业——韩国高速公路公司为例,设计了实现社会价值的相关措施,并强调了其对其他公共企业的启示。展开更多
文摘The covered-ice breakup in subarctic to arctic rivers in the early snowmelt season often gives any damage to instruments monitoring physical and chemical factors of water. The serious condition has brought few time series data during the snowmelt runoff except the river stage or discharge. In this study, the contribution of snowmelt runoff to the discharge and sediment load is quantified by monitoring water turbidity and temperature at the lowest gauging station of U. S. Geological Survey in the Yukon River, Alaska, for more than 3 years (June 2006 to September 2009). The turbidity was recorded by a self-recording turbidimeter with a sensor of infrared-ray back-scattering type, of which the window is cleaned by a wiper just before a measurement. The turbidity time series, coupled with frequent river water sampling at mid-channel, produce time series of suspended sediment (SS) concentration, particulate organic carbon (POC) concentration and particulate organic nitrogen (PON) concentration (mg?L–1) by using the high correlation (R2 = 0.747 to 0.790;P 11 to 2.01 × 1011 m3), 8.7% - 22.5% of the annual sediment load (3.94 × 107 to 5.08 × 107 ton), 11.6% - 23.7% of the annual POC flux (4.05 × 105 to 4.77 × 105 ton), and 10.3% - 24.5% of the annual PON flux (2.80 × 104 to 3.44 × 104 ton). In the snowmelt season, the peak suspended sediment concentration preceded the peak discharge by a few days. This probably results from the fluvial sediment erosion in the river channels.
文摘Biogeochemical feedback processes between soil organic carbon (SOC) in high-latitude organic soils and climate change is of great concern for projecting future climate. More accurate models of the SOC stock and its dynamics in organic soil are of increasing importance. As a first step toward creating a soil model that accurately represents SOC dynamics, we have created the Physical and Biogeochemical Soil Dynamics Model (PB-SDM) that couples a land surface model with a SOC dynamics model to simulate the feedback cycle of SOC accumulation and thermal hydrological dynamics of high-latitude soils. The model successfully simulated soil temperatures for observed data from a boreal forest near Fairbanks, and 2000 year simulations indicated that the effect of the feedback cycle of SOC accumulation on soil thickness would result in a significant differences in the amount of SOC.
文摘许多学者指出,不平等和社会资本不足等社会问题是以效率为导向的新自由主义发展战略的局限性。在此背景下,韩国文在寅政府强调社会价值是国家的核心价值。因此,公共机构须优先考虑社会价值。抛开意识形态上的讨论,这些社会和政策上的变化表明需要就如何切实实现社会价值进行具体探讨。公共机构已强化自身社会责任,为地方社区和低收入群体作出贡献。然而,企业往往将社会责任视为阻碍发展的诱因。公共企业作为一种公共机构,具有公司的特点,同时其实现盈利或企业家精神的内在目标可能会受到提升公共性来实现社会价值的限制。因此,公共企业面临着需兼顾社会及商业价值两方面以实现社会价值的挑战。为制定既能提升公共性以实现社会价值,又能确保盈利性的措施,本研究的重点是兼顾公司和社会层面的“创造共享价值(Creating Shared Value,CSV)”。本文探讨了公共企业追求的公共性和盈利性价值,并将企业社会责任(Corporate Social Responsibility,CSR)同创造共享价值进行了比较,旨在使两者都受益。本研究从创造共享价值的角度,以公共企业——韩国高速公路公司为例,设计了实现社会价值的相关措施,并强调了其对其他公共企业的启示。
