Geopotential, dynamic, orthometric and normal height systems and the corrections related to these systems are evaluated in this paper. Along two different routes, with a length of about 5 kilometers, precise leveling ...Geopotential, dynamic, orthometric and normal height systems and the corrections related to these systems are evaluated in this paper. Along two different routes, with a length of about 5 kilometers, precise leveling and gravity measurements are done. One of the routes is in an even field while the other is in a rough field. The magnitudes of orthometric, normal and dynamic corrections are calculated for each route. Orthometric, dynamic, and normal height differences are acquired by adding the corrections to the height differences obtained from geometric leveling. The magnitudes of the corrections between the two routes are compared. In addition, by subtracting orthometric, dynamic, and normal heights from geometric leveling, deviations of these heights from geometric leveling are counted.展开更多
Aerosol is an important component of the atmosphere,and its source,composition,distribution,and effects are highly complicated.Governments and scientists have given much attention to aerosol problems,and it has become...Aerosol is an important component of the atmosphere,and its source,composition,distribution,and effects are highly complicated.Governments and scientists have given much attention to aerosol problems,and it has become a hot topic due to the important role it plays in climate change and the Earth's environment.In this paper,1) the importance of aerosol in climate change,the atmospheric environment,and human health is summarized;2) the recent serious problems of aerosol pollution and the shortage of current aerosol research in China are pointed out;and 3) the necessity to enhance aerosol research in China is emphasized.展开更多
This paper describes principles, methods and results of a large-scale (1: 25,000) structural-geodynamic mapping of Moscow territory. Neotectonic structures of different ranks--elevations and depressions, lineaments...This paper describes principles, methods and results of a large-scale (1: 25,000) structural-geodynamic mapping of Moscow territory. Neotectonic structures of different ranks--elevations and depressions, lineaments and GDAZ (geodynamic active zones) are presented on the map. Geodynamic active zones are linear or isometric crust volumes of different scales that localized spatially, where conditions for tectonic stress concentration and relaxation, and high gradients of movements and rocks deformity are favorable by different reasons. They differ from active faults, which are rare on geodynamic-stable platform territories, by absence of noticeable displacements in rocks and a more geodynamic stability. Nevertheless, GDAZ can be hazard to engineering buildings, since these zones are favorable for developing exogenous (such as erosion, impoundment, karst, sliding, etc.) and endogenous geological processes (such as seismicity, water-fluid permeability and heat flux). They can also become migration and localization channels of nature-anthropogenic pollution.展开更多
One of the most important questions in the science of global change is how to balance the atmospheric CO2 budget. There is a large terrestrial missing carbon sink amounting to about one billion tonnes of carbon per an...One of the most important questions in the science of global change is how to balance the atmospheric CO2 budget. There is a large terrestrial missing carbon sink amounting to about one billion tonnes of carbon per annum. The locations, magnitudes, variations, and mechanisms responsible for this terrestrial missing carbon sink are uncertain and the focus of much continuing debate. Although the positive feedback between global change and silicate chemical weathering is used in geochemical models of atmospheric CO2, this feedback is believed to operate over a long timescale and is therefore generally left out of the current discussion of human impact upon the carbon budget. Here, we show, by synthesizing recent findings in rock weathering research and studies into biological carbon pump effects in surface aquatic ecosystems, that the carbon sink produced by carbonate weathering based on the H2O- carbonate-CO2-aquatic phototroph interaction on land not only totals half a billion tonnes per annum, but also displays a significant increasing trend under the influence of global warming and land use change; thus, it needs to be included in the global carbon budget.展开更多
文摘Geopotential, dynamic, orthometric and normal height systems and the corrections related to these systems are evaluated in this paper. Along two different routes, with a length of about 5 kilometers, precise leveling and gravity measurements are done. One of the routes is in an even field while the other is in a rough field. The magnitudes of orthometric, normal and dynamic corrections are calculated for each route. Orthometric, dynamic, and normal height differences are acquired by adding the corrections to the height differences obtained from geometric leveling. The magnitudes of the corrections between the two routes are compared. In addition, by subtracting orthometric, dynamic, and normal heights from geometric leveling, deviations of these heights from geometric leveling are counted.
基金supported by the National Basic Research Program of China(2012CB955303)the National Natural Science Foundation of China(41175131)
文摘Aerosol is an important component of the atmosphere,and its source,composition,distribution,and effects are highly complicated.Governments and scientists have given much attention to aerosol problems,and it has become a hot topic due to the important role it plays in climate change and the Earth's environment.In this paper,1) the importance of aerosol in climate change,the atmospheric environment,and human health is summarized;2) the recent serious problems of aerosol pollution and the shortage of current aerosol research in China are pointed out;and 3) the necessity to enhance aerosol research in China is emphasized.
文摘This paper describes principles, methods and results of a large-scale (1: 25,000) structural-geodynamic mapping of Moscow territory. Neotectonic structures of different ranks--elevations and depressions, lineaments and GDAZ (geodynamic active zones) are presented on the map. Geodynamic active zones are linear or isometric crust volumes of different scales that localized spatially, where conditions for tectonic stress concentration and relaxation, and high gradients of movements and rocks deformity are favorable by different reasons. They differ from active faults, which are rare on geodynamic-stable platform territories, by absence of noticeable displacements in rocks and a more geodynamic stability. Nevertheless, GDAZ can be hazard to engineering buildings, since these zones are favorable for developing exogenous (such as erosion, impoundment, karst, sliding, etc.) and endogenous geological processes (such as seismicity, water-fluid permeability and heat flux). They can also become migration and localization channels of nature-anthropogenic pollution.
基金supported by the National BasicResearch Program of China(2013CB956703)the National Natural Science Foundation of China(41430753 and 41172232)
文摘One of the most important questions in the science of global change is how to balance the atmospheric CO2 budget. There is a large terrestrial missing carbon sink amounting to about one billion tonnes of carbon per annum. The locations, magnitudes, variations, and mechanisms responsible for this terrestrial missing carbon sink are uncertain and the focus of much continuing debate. Although the positive feedback between global change and silicate chemical weathering is used in geochemical models of atmospheric CO2, this feedback is believed to operate over a long timescale and is therefore generally left out of the current discussion of human impact upon the carbon budget. Here, we show, by synthesizing recent findings in rock weathering research and studies into biological carbon pump effects in surface aquatic ecosystems, that the carbon sink produced by carbonate weathering based on the H2O- carbonate-CO2-aquatic phototroph interaction on land not only totals half a billion tonnes per annum, but also displays a significant increasing trend under the influence of global warming and land use change; thus, it needs to be included in the global carbon budget.