Research of the Method of Local Topography Rapid Reconstructed

2009 ◽  
pp. 510-516
Author(s):  
Minrong Zhao ◽  
Shengli Deng ◽  
Ze Shi
Keyword(s):  
Local Topography

scholarly journals Structure, Diversity, and Environmental Determinants of High-Latitude Threatened Conifer Forests

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 775
Author(s):  
Carlos Esse ◽  
Francisco Correa-Araneda ◽  
Cristian Acuña ◽  
Rodrigo Santander-Massa ◽  
Patricio De Los Ríos-Escalante ◽  
...  
Keyword(s):  
Water Table ◽  
Environmental Variables ◽  
National Park ◽  
High Water ◽  
Forest Communities ◽  
Competitive Effect ◽  
Forest Patches ◽  
Last Glaciation ◽  
The World ◽  
Local Topography

Pilgerodendron uviferum (D. Don) Florin is an endemic, threatened conifer that grows in South America. In the sub-Antarctic territory, one of the most isolated places in the world, some forest patches remain untouched since the last glaciation. In this study, we analyze the tree structure and tree diversity and characterize the environmental conditions where P. uviferum-dominated stands develop within the Magellanic islands in Kawésqar National Park, Chile. An environmental matrix using the databases WorldClim and SoilGrids and local topography variables was used to identify the main environmental variables that explain the P. uviferum-dominated stands. PCA was used to reduce the environmental variables, and PERMANOVA and nMDS were used to evaluate differences among forest communities. The results show that two forest communities are present within the Magellanic islands. Both forest communities share the fact that they can persist over time due to the high water table that limits the competitive effect from other tree species less tolerant to high soil water table and organic matter. Our results contribute to knowledge of the species’ environmental preference and design conservation programs.

A quantitative method to detect the ventilation paths in a mountainous urban city for urban planning: A case study in Guizhou, China

2016 ◽  
Vol 26 (3) ◽  
pp. 422-437 ◽  
Author(s):  
Shi Ling Chen ◽  
Jun Lu ◽  
Wei Wei Yu
Keyword(s):  
Land Use ◽  
Urban Land Use ◽  
Frontal Area ◽  
High Mountain ◽  
Least Cost Path ◽  
Area Index ◽  
Mapping Procedure ◽  
Urban City ◽  
Local Topography ◽  
The Government

In this paper, a new frontal area index (FAI) mapping method is presented to describe the surface roughness of Renhuai, as an example of typical medium high mountain gorge type Karst city. Comparing with the traditional calculating method of FAI, a local topography (hills) factor is added to the calculation of the FAI in each 100 m × 100 m grid cell. The results show that the modified FAI is more strongly related to the mountainous land-use type than traditional, and local topography regions with large podium structure had higher values than other urban land-use types in mountainous city. With the frontal area index mapping procedure and a self-compiled least cost path analysis method, the potential airflow corridors traversing through the study area can be located, and the total computation time is shorter and less than 1 s. Air volume, a significant measurement index of urban ventilation capacity, is then simulated in computational fluid dynamics model (CFD-PHOENICS) to confirm the significance and efficiency of these specific ventilation corridors. Based on our findings, the government and urban planners may use the descendent maps to understand the urban ventilation paths within a mountainous city for urban local renovation decisions.

scholarly journals The Driving Mechanisms on Southern Ocean Upwelling Change during the Last Deglaciation

Geosciences ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 266
Author(s):  
Wei Liu ◽  
Zhengyu Liu ◽  
Shouwei Li
Keyword(s):  
Southern Ocean ◽  
Climate Model ◽  
Model Simulation ◽  
Early Stage ◽  
Surface Wind ◽  
Ekman Pumping ◽  
Last Deglaciation ◽  
Buoyancy Forcing ◽  
Local Topography ◽  
The Last Deglaciation

We explore the change in Southern Ocean upwelling during the last deglaciation, based on proxy records and a transient climate model simulation. Our analyses suggest that, beyond a conventional mechanism of the Southern Hemisphere westerlies shift, Southern Ocean upwelling is strongly influenced by surface buoyancy forcing and the local topography. Over the Antarctic Circumpolar Current region, the zonal mean and local upwelled flows exhibited distinct evolution patterns during the last deglaciation, since they are driven by different mechanisms. The zonal mean upwelling is primarily driven by surface wind stress via zonal mean Ekman pumping, whereas local upwelling is driven by both wind and buoyancy forcing, and is tightly coupled to local topography. During the early stage of the last deglaciation, the vertical extension of the upwelled flows increased downstream of submarine ridges but decreased upstream, which led to enhanced and diminished local upwelling, downstream and upstream of the submarine ridges, respectively.

De watervoorziening op de zandgronden

2019 ◽  
Vol 4 (2) ◽  
pp. 74-88
Author(s):  
BERT GROENEWOUDT
Keyword(s):  
Drinking Water ◽  
The Netherlands ◽  
Water Supply ◽  
Rural Areas ◽  
Functional Differentiation ◽  
16Th Century ◽  
14Th Century ◽  
Local Topography ◽  
Spatio Temporal ◽  
Settlement Landscape

Water supply in the sandy dry lands (the Netherlands). Spatio-temporal developments Wells as water facilities were standard elements of the Dutch settlement landscape only since the Roman period. At the same time (drinking) water facilities became largely detached from the local topography. The position of a well within a settlement became determined by that of its associated house, and its position relative to the house became more or less fixed. This reflects the functional and social subdivision of the farmhouse into two distinct sections: ‘front’ and ‘back’. Communal water facilities (socially important as well) seem to have been associated with nucleated settlement, and they always existed alongside private facilities. Communal (public) wells first appeared in towns around the 13th or 14th century, but in rural areas probably not until the 16th century. In different periods there is evidence for the expression of social and functional differentiation.

scholarly journals Observing Plumes and Overturning Cells with a New Coastal Bottom Drifter

2018 ◽  
Vol 35 (8) ◽  
pp. 1675-1686 ◽  
Author(s):  
Lena M. Schulze Chretien ◽  
Kevin Speer
Keyword(s):  
Ocean Circulation ◽  
Small Scale ◽  
Coastal Environments ◽  
Constant Depth ◽  
Physical Processes ◽  
Apalachicola Bay ◽  
Local Topography ◽  
Tracking Device ◽  
To Receive ◽  
Drifter Trajectory

AbstractA new platform, the Coastal Bottom Drifter, was designed and built to observe near-bottom environments in coastal regions. It is capable of observing properties by drifting near the bottom with a prescribed clearance or at a constant depth of up to 300 m. The platform can observe physical and biochemical parameters, such as temperature, salinity, oxygen, and velocities, and has the capacity to carry additional sensors to measure, for example, pH, turbidity, and nutrients. In addition, it can profile to the surface at chosen intervals and can be deployed for days or up to several months. The integrated Iridium communication allows the user to receive positions and data while the platform is surfaced, as well as send new missions to the instrument. The use of an acoustic bottom-tracking device allows the construction of a drifter trajectory while providing information about ocean circulation. Additionally, the ADCP provides information about suspended particles and possible sediment transport. These measurements are valuable in understanding coastal environments as well as the dominant physical processes that cause mixing and set the conditions for local biological activity. An example deployment in Apalachicola Bay shown in this study demonstrates the ability of the drifter to observe small-scale features, such as overturning cells and plumes of dense water, that are caused by local topography.

scholarly journals STUDY OF OVERHEAD POWER LINE CORRIDORS ON THE TERRITORY OF PSKOV REGION (RUSSIA) BASED ON SATELLITE SOUNDING DATA

2019 ◽  
Vol 1 ◽  
pp. 164
Author(s):  
Sergei Mikhalap ◽  
Sergei Trashenkov ◽  
Vera Vasilyeva
Keyword(s):  
Radar Data ◽  
National Standards ◽  
Multispectral Images ◽  
Synthetic Aperture Radar Data ◽  
Local Topography ◽  
Pskov Region ◽  
Pass Through ◽  
Overhead Power Lines ◽  
Overhead Power Line ◽  
Dynamics Of Vegetation

Overhead power lines (OPL) form the basis of a power grid. Reliable energy supply depends on no-failure operation of these long-length elements of energy infrastructure. More than 12,000 km out of 45,000 km of OPL in Pskov region (Russia) pass through forests. This study investigates the possibilities of using satellite-sensing data to assess the conditions of corridors for OPL with different voltage levels. Authors evaluated compliance of actual data with requirements of national standards. The dynamics of vegetation and local topography based on synthetic aperture radar data and multispectral images were taken into account.

Correlation Analysis between Grounding Resistance and Diurnal Variations of Upper Soil Resistivity during March 2010 in Balozhi, Latvia

2010 ◽  
Vol 27 (1) ◽  
pp. 88-91 ◽  
Author(s):  
Marina Kizhlo ◽  
Arvids Kanbergs ◽  
Mihails Kizhlo
Keyword(s):  
Correlation Analysis ◽  
Meteorological Factors ◽  
Soil Layer ◽  
Considerable Effect ◽  
Diurnal Variations ◽  
Electrical Safety ◽  
Soil Resistivity ◽  
Grounding System ◽  
Grounding Resistance ◽  
Local Topography

Correlation Analysis between Grounding Resistance and Diurnal Variations of Upper Soil Resistivity during March 2010 in Balozhi, LatviaThe accurate measurement of soil resistivity and grounding system resistance is fundamental to electrical safety. However, geological and meteorological factors can have a considerable effect on the accuracy of conventional measurements and the validity of the measurement methods. This paper examines some aspects of grounding measurements and grounding system performance in the context of both geological and meteorological effects.We are reporting the results of grounding measurements using the 3-point method with ground resistivity tester type M416. The measurements were conducted during selected period from 2010 March 1 to March 31 in Balozhi, Latvia. We also noted that the resistivity of the upper layer significantly varied from a point to another, reflecting difference in water content in the upper soil layer due to local topography and other parameters.

scholarly journals Mosaics of canopy openness induced by tropical cyclones in lowland rain forests with contrasting management histories in northeastern Australia

2000 ◽  
Vol 16 (6) ◽  
pp. 883-894 ◽  
Author(s):  
SIMON J. GROVE ◽  
STEPHEN M. TURTON ◽  
DANNY T. SIEGENTHALER
Keyword(s):  
Forest Management ◽  
Forest Canopy ◽  
Canopy Openness ◽  
Old Growth ◽  
Lowland Rain Forest ◽  
Forest Sites ◽  
Local Topography ◽  
Marked Points ◽  
Impacted Site

Tropical Cyclone ‘Rona’ crossed the coast of the Daintree lowlands of northeastern Australia in 1999. This study reports on its impact on forest canopy openness at six lowland rain forest sites with contrasting management histories (old-growth, selectively logged and regrowth). Percentage canopy openness was calculated from individual hemispherical photographs taken from marked points below the forest canopy at nine plots per site 3–4 mo before the cyclone, and at the same points a month afterwards. Before the cyclone, when nine sites were visited, canopy openness in old-growth and logged sites was similar, but significantly higher in regrowth forest. After the cyclone, all six revisited sites showed an increase in canopy openness, but the increase was very patchy amongst plots and sites and varied from insignificant to severe. The most severely impacted site was an old-growth one, the least impacted a logged one. Although proneness to impact was apparently related to forest management history (old-growth being the most impacted), underlying local topography may have had an equally strong influence in this case. It was concluded that the likelihood of severe impact may be determined at the landscape-scale by the interaction of anthropogenic with meteorological, physiographic and biotic factors. In the long term, such interactions may caution against pursuing forest management in cyclone-prone areas.

scholarly journals Urban heat island in Bloemfontein during winter

2013 ◽  
Vol 32 (1) ◽  
Author(s):  
Pieter Snyman ◽  
A. Stephen Steyn
Keyword(s):  
Maximum Intensity ◽  
Urban Heat Islands ◽  
Urban Air ◽  
Heat Island ◽  
Heat Islands ◽  
Air Temperatures ◽  
Local Topography ◽  
Urban Heat ◽  
The Difference ◽  
The City

Urban heat islands (UHIs) are characterised by warmer urban air temperatures compared to rural air temperatures, and the intensity is equal to the difference between the two. Air temperatures are measured at various sites across the city of Bloemfontein and then analysed to determine the UHI characteristics. The UHI is found to have a horseshoe shape and reaches a maximum intensity of 8.2 °C at 22:00. The UHI is largely affected by the local topography.

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