The maximum rate of carboxylation （Vcax） is a key photosynthetic parameter for gross primary produc- tion （GPP） estimation in terrestrial biosphere models. A set of observation-based Vcax values, which take the ni...The maximum rate of carboxylation （Vcax） is a key photosynthetic parameter for gross primary produc- tion （GPP） estimation in terrestrial biosphere models. A set of observation-based Vcax values, which take the ni- trogen limitation on photosynthetic rates into consideration, are used in version 4.5 of the Community Land Model （CLM4.5）. However, CLM4.5 with carbon-nitrogen （CN） biogeochemistry （CLM4.5-CN） still uses an inde- pendent decay coefficient for nitrogen after the photosyn- thesis calculation. This means that the nitrogen limitation on the carbon cycle is accounted for twice when CN bio- geochemistry is active. Therefore, to avoid this double nitrogen down-regulation in CLM4.5-CN, the original Vcmax scheme is revised with a new one that only accounts for the transition between Vcmax and its potential value （without nitrogen limitation）. Compared to flux tower- based observations, the new Vcmax scheme reduces the root-mean-square error （RMSE） in GPP for China's Mainland by 13.7 g C m-2 yr-1, with a larger decrease over humid areas （39.2 g C m 2 yr-1）. Moreover, net primary production and leaf area index are also improved, with reductions in RMSE by 0.8% and 11.5%, respectively.展开更多
This paper was made using a descriptive analysis of some indicators from the data basis of Economic Commission for Latin America （CEPAL）, CEPAL and answers the question： Have there been enough foreign trade dynamic...This paper was made using a descriptive analysis of some indicators from the data basis of Economic Commission for Latin America （CEPAL）, CEPAL and answers the question： Have there been enough foreign trade dynamics during the last years （1999-2006） in order to reduce social inequality gaps？ The results here shown correspond to the first stage of a research that relates poverty to countries＇ economic productivity. The article presents foreign trade, economic growth, and social inequality overview in the countries of the Andean Community of Nations during the years 1999-2006. In considering this period, the last international crisis is overlooked, but it takes in account the importance of the Millennium Development Goals set by the UNDP. The analysis of the basic indicators reflects that the dynamics of economic integration and foreign trade do not translate into better social equality and poverty reduction. This paper shows an economic and social contrast obtained from the results by countries of the Andean Community of Nations （CAN） during the years 1999-2006, comprised by Colombia, Peru, Ecuador, Bolivia, and Venezuela, though the last country is not currently part of CAN. These indicators are exports, imports, relative commercial balance, gross domestic product, gross domestic product per capita, unemployment, GINI index, population, urban development index, and poverty. The paper presents a succinct conceptual framework where the relationship between foreign trade and social inequality is established, from which the description and analysis of the proposed indicators is formulated, permitting the establishing of an apparent practical connection between economic behavior and social results from the CAN countries.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.91125016 and 41305066)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA05110102)
文摘The maximum rate of carboxylation （Vcax） is a key photosynthetic parameter for gross primary produc- tion （GPP） estimation in terrestrial biosphere models. A set of observation-based Vcax values, which take the ni- trogen limitation on photosynthetic rates into consideration, are used in version 4.5 of the Community Land Model （CLM4.5）. However, CLM4.5 with carbon-nitrogen （CN） biogeochemistry （CLM4.5-CN） still uses an inde- pendent decay coefficient for nitrogen after the photosyn- thesis calculation. This means that the nitrogen limitation on the carbon cycle is accounted for twice when CN bio- geochemistry is active. Therefore, to avoid this double nitrogen down-regulation in CLM4.5-CN, the original Vcmax scheme is revised with a new one that only accounts for the transition between Vcmax and its potential value （without nitrogen limitation）. Compared to flux tower- based observations, the new Vcmax scheme reduces the root-mean-square error （RMSE） in GPP for China's Mainland by 13.7 g C m-2 yr-1, with a larger decrease over humid areas （39.2 g C m 2 yr-1）. Moreover, net primary production and leaf area index are also improved, with reductions in RMSE by 0.8% and 11.5%, respectively.
文摘This paper was made using a descriptive analysis of some indicators from the data basis of Economic Commission for Latin America （CEPAL）, CEPAL and answers the question： Have there been enough foreign trade dynamics during the last years （1999-2006） in order to reduce social inequality gaps？ The results here shown correspond to the first stage of a research that relates poverty to countries＇ economic productivity. The article presents foreign trade, economic growth, and social inequality overview in the countries of the Andean Community of Nations during the years 1999-2006. In considering this period, the last international crisis is overlooked, but it takes in account the importance of the Millennium Development Goals set by the UNDP. The analysis of the basic indicators reflects that the dynamics of economic integration and foreign trade do not translate into better social equality and poverty reduction. This paper shows an economic and social contrast obtained from the results by countries of the Andean Community of Nations （CAN） during the years 1999-2006, comprised by Colombia, Peru, Ecuador, Bolivia, and Venezuela, though the last country is not currently part of CAN. These indicators are exports, imports, relative commercial balance, gross domestic product, gross domestic product per capita, unemployment, GINI index, population, urban development index, and poverty. The paper presents a succinct conceptual framework where the relationship between foreign trade and social inequality is established, from which the description and analysis of the proposed indicators is formulated, permitting the establishing of an apparent practical connection between economic behavior and social results from the CAN countries.
