Spatiotemporal evolution and driving forces of changes in rural settlements in the poverty belt around Beijing and Tianjin: a case study of Zhangjiakou city, Hebei Province

Ecosystem services management should often expect to deal with non-linearities due to trade-offs and synergies between ecosystem services (ES). Therefore, it is important to analyze long-term trends in ES development and utilization to understand their responses to climate change and intensification of human activities. In this paper, the region of Uxin in Inner Mongolia, China, was chosen as a case study area to describe the spatial distribution and trends of 5 ES indicators. Changes in relationships between ES and driving forces of dynamics of ES relationships were analyzed for the period 1979–2016 using a stepwise regression. We found that: the magnitude and directions in ES relationships changed during this extended period; those changes are influenced by climate factors, land use change, technological progress, and population growth.

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Spatiotemporal variation analysis of driving forces of urban land spatial expansion using logistic regression: A case study of port towns in Taicang City, China

Habitat International ◽

10.1016/j.habitatint.2014.02.004 ◽

2014 ◽

Vol 43 ◽

pp. 181-190 ◽

Cited By ~ 79

Author(s):

Bangrong Shu ◽

Honghui Zhang ◽

Yongle Li ◽

Yi Qu ◽

Lihong Chen

Keyword(s):

Logistic Regression ◽

Driving Forces ◽

Urban Land ◽

Spatiotemporal Variation ◽

Spatial Expansion ◽

Variation Analysis

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The roles of vertical advection and eddy diffusion in the equatorial mesospheric semi-annual oscillation (MSAO)

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-7813-2013 ◽

2013 ◽

Vol 13 (15) ◽

pp. 7813-7824 ◽

Cited By ~ 4

Author(s):

R. L. Gattinger ◽

E. Kyrölä ◽

C. D. Boone ◽

W. F. J. Evans ◽

K. A. Walker ◽

...

Keyword(s):

Driving Forces ◽

Eddy Diffusion ◽

Equatorial Region ◽

Local Times ◽

Model Simulations ◽

Vertical Advection ◽

Diffusion Rates ◽

D Model ◽

Vertical Eddy

Abstract. Observations of the mesospheric semi-annual oscillation (MSAO) in the equatorial region have been reported dating back several decades. Seasonal variations in both species densities and airglow emissions are well documented. The extensive observations available offer an excellent case study for comparison with model simulations. A broad range of MSAO measurements is summarised with emphasis on the 80–100 km region. The objective here is not to address directly the complicated driving forces of the MSAO, but rather to employ a combination of observations and model simulations to estimate the limits of some of the underlying dynamical processes. Photochemical model simulations are included for near-equinox and near-solstice conditions, the two times with notable differences in the observed MSAO parameters. Diurnal tides are incorporated in the model to facilitate comparisons of observations made at different local times. The roles of water vapour as the "driver" species and ozone as the "response" species are examined to test for consistency between the model results and observations. The simulations suggest the interactions between vertical eddy diffusion and background vertical advection play a significant role in the MSAO phenomenon. Further, the simulations imply there are rigid limits on vertical advection rates and eddy diffusion rates. For August at the Equator, 90 km altitude, the derived eddy diffusion rate is approximately 1 × 106 cm2 s−1 and the vertical advection is upwards at 0.8 cm s−1. For April the corresponding values are 4 × 105 cm2 s−1 and 0.1 cm s−1. These results from the current 1-D model simulations will need to be verified by a full 3-D simulation. Exactly how vertical advection and eddy diffusion are related to gravity wave momentum as discussed by Dunkerton (1982) three decades ago remains to be addressed.

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