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981.
Bailang Yu Ting Lian Yixiu Huang Xinyue Ye Zuoqi Chen 《International journal of geographical information science》2019,33(4):687-706
The population distribution grid at fine scales better reflects the distribution of residents and plays an important role in investigating urban systems. The recent years have witnessed a growing trend of applying the nighttime light data to the estimation of population at micro levels. However, using the nighttime light data alone to estimate population may cause the overestimation problem due to excessively high light radiance in specific types of areas such as commercial zones and transportation hubs. In dealing with this issue, this study used taxi trajectory data that delineate people’s movements, and explored the utility of integrating the nighttime light and taxi trajectory data in the estimation of population in Shanghai at the spatial resolution of 500 m. First, the initial population distribution grid was generated based on the NPP-VIIRS nighttime light data. Then, a calibration grid was created with taxi trajectory data, whereby the initial population grid was optimized. The accuracy of the resultant population grid was assessed by comparing it with the refined survey data. The result indicates that the final population distribution grid performed better than the initial population grid, which reflects the effectiveness of the proposed calibration process. 相似文献
982.
Groundwater is a key factor controlling the growth of vegetation in desert riparian systems. It is important to recognise how groundwater changes affect the riparian forest ecosystem. This information will not only help us to understand the ecological and hydrological process of the riparian forest but also provide support for ecological recovery of riparian forests and water-resources management of arid inland river basins. This study aims to estimate the suitability of the Water Vegetation Energy and Solute Modelling(WAVES) model to simulate the Ejina Desert riparian forest ecosystem changes,China, to assess effects of groundwater-depth change on the canopy leaf area index(LAI) and water budgets, and to ascertain the suitable groundwater depth for preserving the stability and structure of desert riparian forest. Results demonstrated that the WAVES model can simulate changes to ecological and hydrological processes. The annual mean water consumption of a Tamarix chinensis riparian forest was less than that of a Populus euphratica riparian forest, and the canopy LAI of the desert riparian forest should increase as groundwater depth decreases. Groundwater changes could significantly influence water budgets for T. chinensis and P. euphratica riparian forests and show the positive and negative effects on vegetation growth and water budgets of riparian forests. Maintaining the annual mean groundwater depth at around 1.7-2.7 m is critical for healthy riparian forest growth. This study highlights the importance of considering groundwater-change impacts on desert riparian vegetation and water-balance applications in ecological restoration and efficient water-resource management in the Heihe River Basin. 相似文献
983.
Spiridonov E. A. Vinogradova O. Yu. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(11):1814-1819
Izvestiya, Atmospheric and Oceanic Physics - A method for calculating of the Earth’s surface displacements due to atmospheric loading effect is presented. The load displacements are... 相似文献
984.
Izvestiya, Atmospheric and Oceanic Physics - In this paper we study the evolution of the matter distribution pattern of ink droplets falling freely into calm water and forming a cumulative back jet... 相似文献
985.
Mikhailov E. F. Ivanova O. A. Nebosko E. Yu. Vlasenko S. S. Ryshkevich T. I. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(4):357-364
Izvestiya, Atmospheric and Oceanic Physics - Bioparticles constitute a significant fraction of atmospheric aerosol. Their size range varies from nanometers (macromolecules) to hundreds of... 相似文献
986.
Polnikov V. G. Baidakov G. A. Troitskaya Yu. I. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(5):492-501
Izvestiya, Atmospheric and Oceanic Physics - The aim of this work is to obtain estimates and parameterization of the dissipation rate of the turbulence kinetic energy (TKE dissipation), ε,... 相似文献
987.
Zaytsev A. I. Babeyko A. Yu. Kurkin A. A. Yalciner A. C. Pelinovsky E. N. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(5):462-469
Izvestiya, Atmospheric and Oceanic Physics - Tsunami forecast possibilities for areas with a small base of historical tsunamis have been discussed using the Probabilistic Tsunami Hazard Assessment... 相似文献
988.
Ampilov Yu. P. Terekhina Ya. E. Tokarev M. Yu. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(7):705-720
Izvestiya, Atmospheric and Oceanic Physics - This article focuses on the study of the information value of offshore technologies based on the generation of acoustic signals in water in a wide... 相似文献
989.
Izvestiya, Atmospheric and Oceanic Physics - A Convers Avia Airline Mi-8 helicopter crashed near the Russian settlement of Barentsburg on October 26, 2017. The moment of impact was recorded by the... 相似文献
990.
Oceanology - Based on long-term data on the spatial distribution and fluxes of streaming (bubbling) methane in the Black Sea, the study considers various types of streaming gas emissions... 相似文献