Long-Term Eddy Covariance Monitoring of Evapotranspiration and Its Environmental Factors in a Temperate Mixed Forest in Northeast China

Carbon (C) isotope discrimination during photosynthetic CO2 assimilation has been extensively studied, but the whole process of fractionation from leaf to soil has been less well investigated. In the present study, we investigated the δ13C signature along the C transfer pathway from air to soil in a coniferous and broad-leaved mixed forest in northeast China and examined the relationship between δ13C of respiratory fluxes (leaf, trunk, soil, and the entire ecosystem) and environmental factors over a full growing season. This study found that the δ13C signal of CO2 from canopy air was strongly imprinted in the organic and respiratory pools throughout C transfer due to the effects of discrimination and isotopic mixing on C assimilation, allocation, and respiration processes. A significant difference in isotopic patterns was found between conifer and broadleaf species in terms of seasonal variations in leaf organic matter. This study also found that δ13C in trunk respiration, compared with that in leaf and soil respiration, was more sensitive to seasonal variations of environmental factors, especially soil temperature and soil moisture. Variation in the δ13C of ecosystem respiration was correlated with air temperature with no time lag and correlated with soil temperature and vapor pressure deficit with a lag time of 10 days, but this correlation was relatively weak, indicating a delayed linkage between above- and belowground processes. The isotopic linkage might be confounded by variations in atmospheric aerodynamic and soil diffusion conditions. These results will help with understanding species differences in isotopic patterns and promoting the incorporation of more influencing factors related to isotopic variation into process-based ecosystem models.

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Research on the Economic Vitality of the Northeast China

Journal of Economic Science Research ◽

10.30564/jesr.v3i3.1829 ◽

2020 ◽

Vol 3 (3) ◽

Author(s):

Jiayue Jiao

Keyword(s):

Northeast China ◽

Practical Significance ◽

Economic Policies ◽

Regional Competitiveness ◽

Regional Economic ◽

Important Indicator ◽

Depth Study ◽

Long Term Impact ◽

Economic Vitality

Economic vitality is an important indicator of regional competitiveness. The demand for talents and the vitality of enterprises in different regions are obvious to all and have practical significance. Therefore, it is necessary to establish a survey data model and conduct in-depth study on improving regional economic vitality from the perspective of policy.Based on a variety of forecasting methods, this paper analyzes the short-term and long-term impact of economic policies in Northeast China, and finally puts forward the factors that affect the economic vitality of northeast policies. Finally, the paper puts forward the feasibility and targeted suggestions of strengthening regional economic vitality, obtaining long-term development and building a more competitive city in the new era.

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Regional variability in black carbon and carbon monoxide ratio from long-term observations over East Asia: assessment of representativeness for black carbon (BC) and carbon monoxide (CO) emission inventories

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-83-2020 ◽

2020 ◽

Vol 20 (1) ◽

pp. 83-98 ◽

Cited By ~ 5

Author(s):

Yongjoo Choi ◽

Yugo Kanaya ◽

Seung-Myung Park ◽

Atsushi Matsuki ◽

Yasuhiro Sadanaga ◽

...

Keyword(s):

Carbon Monoxide ◽

South Korea ◽

East Asia ◽

Black Carbon ◽

North Korea ◽

Northeast China ◽

Emission Inventory ◽

East China ◽

Co Emission

Abstract. The black carbon (BC) and carbon monoxide (CO) emission ratios were estimated and compiled from long-term, harmonized observations of the ΔBC∕ΔCO ratios under conditions unaffected by wet deposition at four sites in East Asia, including two sites in South Korea (Baengnyeong and Gosan) and two sites in Japan (Noto and Fukuoka). Extended spatio-temporal coverage enabled estimation of the full seasonality and elucidation of the emission ratio in North Korea for the first time. The estimated ratios were used to validate the Regional Emission inventory in ASia (REAS) version 2.1 based on six study domains (“East China”, “North China”, “Northeast China”, South Korea, North Korea, and Japan). We found that the ΔBC∕ΔCO ratios from four sites converged into a narrow range (6.2–7.9 ng m−3 ppb−1), suggesting consistency in the results from independent observations and similarity in source profiles over the regions. The BC∕CO ratios from the REAS emission inventory (7.7 ng m−3 ppb−1 for East China – 23.2 ng m−3 ppb−1 for South Korea) were overestimated by factors of 1.1 for East China to 3.0 for South Korea, whereas the ratio for North Korea (3.7 ng m−3 ppb−1 from REAS) was underestimated by a factor of 2.0, most likely due to inaccurate emissions from the road transportation sector. Seasonal variation in the BC∕CO ratio from REAS was found to be the highest in winter (China and North Korea) or summer (South Korea and Japan), whereas the measured ΔBC∕ΔCO ratio was the highest in spring in all source regions, indicating the need for further characterization of the seasonality when creating a bottom-up emission inventory. At levels of administrative districts, overestimation in Seoul, the southwestern regions of South Korea, and Northeast China was noticeable, and underestimation was mainly observed in the western regions in North Korea, including Pyongyang. These diagnoses are useful for identifying regions where revisions in the inventory are necessary, providing guidance for the refinement of BC and CO emission rate estimates over East Asia.

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Behavioral medicine challenges in the shadow of a global pandemic

Translational Behavioral Medicine ◽

10.1093/tbm/ibaa106 ◽

2020 ◽

Author(s):

Alyssa T Brooks ◽

Hannah K Allen ◽

Louise Thornton ◽

Tracy Trevorrow

Keyword(s):

Environmental Factors ◽

Health Behavior ◽

Health Behaviors ◽

Natural Experiment ◽

Direct Effects ◽

Global Pandemic ◽

Wide Range ◽

Future Data ◽

Short And Long Term

Abstract Health behavior researchers should refocus and retool as it becomes increasingly clear that the challenges of the COVID-19 pandemic surpass the direct effects of COVID-19 and include unique, drastic, and ubiquitous consequences for health behavior. The circumstances of the pandemic have created a natural experiment, allowing researchers focusing on a wide range of health behaviors and populations with the opportunity to use previously collected and future data to study: (a) changes in health behavior prepandemic and postpandemic, (b) health behavior prevalence and needs amidst the pandemic, and (c) the effects of the pandemic on short- and long-term health behavior. Our field is particularly challenged as we attempt to consider biopsychosocial, political, and environmental factors that affect health and health behavior. These realities, while daunting, should call us to action to refocus and retool our research, prevention, and intervention efforts

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