浅谈地理微信公众号的运营——以公众号“樵高地理”为例

“樵高地理”微信公众号由“杂烩地理”“微课地理”“习题地理”三大板块组成,利用微信公众平台将地理知识、教学活动延伸到课外,用学生喜爱的方式激发他们学习地理的兴趣,传播给他们有用的知识,促进地理教学效率的提升。

地理课堂中的艺术教学

在地理课堂中，除了要讲授地理学科知识的外，还要注意老师与学生的交流，联系和沟通师生的关系，达到课堂的气氛和效率。

Using 4C OBS to reveal the distribution and velocity attributes of gas hydrates at the northern continental slope of South China Sea

To investigate the distribution and velocity attributes of gas hydrates in the northern continental slope of South China Sea, Guangzhou Marine Geological Survey conducted four-component （4C） ocean-bottom seismometer （OBS） surveys. A case study is presented to show the results of acquiring and processing OBS data for detecting gas hydrates. Key processing steps such as repositioning, reorientation, PZ summation, and mirror imaging are discussed. Repositioning and reorientation find the correct location and direction of nodes. PZ summation matches P- and Z-components and sums them to separate upgoing and downgoing waves. Upgoing waves are used in conventional imaging, whereas downgoing waves are used in mirror imaging. Mirror imaging uses the energy of the receiver ghost reflection to improve the illumination of shallow structures, where gas hydrates and the associated bottom-simulating reflections （BSRs） are located. We developed a new method of velocity analysis using mirror imaging. The proposed method is based on velocity scanning and iterative prestack time migration. The final imaging results are promising. When combined with the derived velocity field, we can characterize the BSR and shallow structures; hence, we conclude that using 4C OBS can reveal the distribution and velocity attributes of gas hydrates.

Architecture of HLA Based Distributed Virtual Geographic Environment

Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture are also discussed. The architecture basically meets the need of DVGE in real-time communication, distribution, collaboration, reusing and interoperation, expansion, and standard.

RS AND GIS-BASED FOREST FIRE RISK ZONE MAPPING IN DA HINGGAN MOUNTAINS

The Da Hinggan Mountains is one of the most important forest areas in China, but forest fire there is also of high frequency. So it is completely necessary to map forest fire risk zones in order to effectively manage and protect the forest resources. Two forest farms of Tuqiang Forest Bureau (53 degrees 34'-52 degrees 15'N,124 degrees 05'-122 degrees 18'E) were chosen as typical areas in this study. Remote sensing (RS) and Geographic Information System (GIS) play a vital role and can be used effectively to obtain and combine different forest-fire-causing factors for demarcating the forest fire risk zone map. Forest fire risk zones were described by assigning subjective weights to the classes of all the coverage layers according to their sensitivity to fire, using the ARC/INFO GIS software. Four classes of forest fire risk ranging from low to extremely high were generated automatically in ARC/INFO. The results showed that about 60.33% of the study area were predicted to be upper moderate risk zones, indicating that the forest fire management task in this area is super onerous. The RS and GIS-based forest fire risk model of the study area was found to be highly compatible with the actual fire-affected sites in 1987. Therefore the forest fire risk zone map can be used for guidance of forest fire management, and as basis for fire prevention strategies.

Scale-Dependent Representations of Relief Based on Wavelet Analysis

Automatic generalization of geographic information is the core of multi_scale representation of spatial data,but the scale_dependent generalization methods are far from abundant because of its extreme complicacy.This paper puts forward a new consistency model about scale_dependent representations of relief based on wavelet analysis,and discusses the thresholds in the model so as to acquire the continual representations of relief with different details between scales.The model not only meets the need of automatic generalization but also is scale-dependent completely.Some practical examples are given.

Layering-based Breakpoint Handling in Contour Line Extraction

This paper deals withthe automatic connection of contourlines extracted from a scanned browngeographical map. For the variety oftopographical elements contained on amap, the factors causing the interrup-tion of contour line are also multiform,which make the connection task verydifficult. On the basis of separatingthose elements always making the con-tours break and regarding them as ref-erent layers, a layering-based methodis presented. The purpose is to takeinto account property information (likeinclination and configuration) of con-tour lines when they come across otherdifferent symbols, such as gully, cliff,dry land and elevation annotation etc.In this paper, the authors propose thatit should be far more effective and di-rect to adopt different algorithmic op-erators to different factors than usingsingle one operator to all.

Distributed Modeling of Extraterrestrial Solar Radiation Over the Rugged Terrains of Pakistan

In Pakistan,the solar analogue has been addressed but its surface geographical parameterization has given least attention.Inappropriate density of stations and their spatial coverage particularly in difficult peripheral national territories,little or no solar radiation data,non-satisfactory sunshine hours data,and low quality of ground observed cloud cover data create a situation in which the spatial modeling of Extraterrestrial Solar Radiation(ESR) and its ground parameterization got sufficient scope.The Digital Elevation Model (DEM) input into Geographic Information System (GIS) is a compatible tool to demonstrate the spatial distribution of ESR over the rugged terrains of the study domain.For the first time,distributed modeling of ESR is done over the rugged terrains of Pakistan,based on DEM and ArcGIS..Results clearly depict that the complex landforms profoundly disrupt the zonal distribution of ESR in Pakistan.The screening impact of topography is higher on spatial distribution of ESR in winter and considerably low in summer.The combined effect of topography and latitude is obvious.Hence,the model was further testified by plotting Rb (ratio of ESR quantity over rugged terrain against plane surface) against azimuth at different latitudes with different angled slopes.The results clearly support the strong screening effect of rugged terrain through out the country especially in Himalayas,Karakoram and Hindukush (HKH),western border mountains and Balochistan Plateau.This model can be instrumental as baseline geospatial information for scientific investigations in Pakistan,where substantial fraction of national population is living in mountainous regions.

Landslide Susceptibility Assessment of the Youfang Catchment using Logistic Regression

A detailed landslide susceptibility map was produced in the Youfang catchment using logistic regression method with datasets developed for a geographic information system(GIS).Known as one of the most landslide-prone areas in China, the Youfang catchment of Longnan mountain region,which lies in the transitional area among QinghaiTibet Plateau, loess Plateau and Sichuan Basin, was selected as a representative case to evaluate the frequency and distribution of landslides.Statistical relationships for landslide susceptibility assessment were developed using landslide and landslide causative factor databases.Logistic regression(LR)was used to create the landslide susceptibility maps based on a series of available data sources: landslide inventory; distance to drainage systems, faults and roads; slope angle and aspect; topographic elevation and topographical wetness index, and land use.The quality of the landslide susceptibility map produced in this paper was validated and the result can be used fordesigning protective and mitigation measures against landslide hazards.The landslide susceptibility map is expected to provide a fundamental tool for landslide hazards assessment and risk management in the Youfang catchment.

Key Technologies in the Design and Construction of 300 m Ultra-High Arch Dams

Starting with the Ertan arch dam （240 m high, 3300 MW） in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 （305 m）, Xiaowan （294.5m）, and Xiluodu （285.5 m） arch dams have reached the 300 m height level （i.e., near or over 300 m）, making them the tallest arch dams in the world. The design and construction of these 300 m ultra-high arch dams posed significant challenges, due to high water pressures, high seismic de- sign criteria, and complex geological conditions. The engineering team successfully tackled these chal- lenges and made critical breakthroughs, especially in the area of safety control. In this paper, the author summarizes various key technological aspects involved in the design and construction of 300 m ultra- high arch dams, including the strength and stability of foundation rock, excavation of the dam base and surface treatment, dam shape optimization, safety design guidelines, seismic analysis and design, treatment of a complex foundation, concrete temperature control, and crack prevention. The experience gained from these projects should be valuable for future practitioners.

A necklace of pearl in high altitude medicine and hypoxic physiology in Yushu Earthquake

During Yushu Earthquake,a large number of rescuers flocked to the mountainous quake areas. Under such a very specific circumstance,a high incidence of acute altitude illness was observed in rescuers who rapidly traveled from near sea level to an altitude of 4 000 m. It is evident that acute altitude illness leads to a significant human and economic toll,and also seriously influences the mountain rescue operation. So what does this teach us about mountain rescue in Yushu? Professor Wu Tianyi and many other authors collected shining points of the experiences and drew the lessons from the Yushu Earthquake into this special issue in Engineering Sciences which is like to thread pearl beads for a necklace. What readers learn from this special issue will have implications for the health and well-being of all high altitude populations all over the world.

Seismic Data Processing and Interpretation on the Loess Plateau, Part1: Seismic Data Processing

Branching river channels and the coexistence of valleys, ridges, hiils, and slopes＇as the result of long-term weathering and erosion form the unique loess topography. The Changqing Geophysical Company, working in these complex conditions, has established a suite of technologies for high-fidelity processing and fine interpretation of seismic data. This article introduces the processes involved in the data processing and interpretation and illustrates the results.

Orthorectification of IKONOS and Impact of Different Resolution DEM

IKONOS image has been wildly used in city planning, precision agriculture and emergence response. However, the accuracy of IKONOS Geo product is limited due to distortion caused by terrain relief. Orthorectification was performed to remove the distortion and the impact of different DEM on orthorectification were evaluated. 38 ground control points (GCPs) and 25 independent check points (ICPs) were collected. DEMs were generated from 1∶10 000 and 1∶50 000 topographic maps. Results show that RMS error at the check points is 1.554 0 m using DEM generated from 1∶10 000 topographic map, which can meet the accuracy requirement of IKONOS Precision product (1.9 m RMSE). While RMS error is 2.572 4 m using DEM generated from 1∶50 000 topographic map.

A Spatial Cluster Analysis of Heavy Rains in China

Clustered heavy rains （CHRs） defined using hierarchical cluster analysis based on daily observations of precipitation in China during 1960-2008 are investi- gated in this paper. The geographical pattern of CHRs in China shows three high-frequency centers--South China, the Yangtze River basin, and part of North China around the Bohai Sea. CHRs occur most frequently in South China with a mean annual frequency of 6.8 （a total of 334 times during 1960-2008）. June has the highest monthly frequency （2.2 times/month with a total of 108 times dur- ing 1960-2008）, partly in association with the Meiyu phenomenon in the Yangtze River basin. Within the past 50 years, the frequency of CHRs in China has increased significantly from 13.5 to 17.3 times per year, which is approximately 28%. In the 1990s, the frequency of CHRs often reached 19.1 times per year. The geographical extent of CHR has expanded slightly by 0.5 stations, and its average daily rainfall intensity has increased by 3.7 mm d-1. The contribution of CHRs to total rainfall amount and the frequency of daily precipitation have increased by 63.1% and 22.7%, respectively, partly due to a significant decrease in light rains. In drying regions of North and Northeast China, the amounts of minimal CHRs have had no significant trend in recent years, probably due to warming in these arid regions enhancing atmospheric conveetivity at individual stations.

Establishment and Data Processing of High-Precision City Subsidence Monitoring Network by GPS Surveying Instead of Leveling

The feasibility of moni-toring the change of city settlementusing GPS surveying instead of level-ing is studied. A fiducial network anda monitoring network are establishedin Ningbo city. Two periods of GPSobservation are completed. Somemeasures are taken during the obser-vation in order to ensure to obtain thehigh-precise height component. TheSaastamoinen model is adopted in thedata processing of the dry componentpart of the tropospheric delay. Thewet component change of the tropo-spheric delay is estimated by stochasticprocesses model. When Bernese soft-ware is used to process the data, themillimeter level precision of heightmeasuring is achieved.

GIS-based Effect Assessment of Soil Erosion Before and After Gully Land Consolidation: A Case Study of Wangjiagou Project Region, Loess Plateau

The Loess Plateau is one typical area of serious soil erosion in the world. China has implemented ′Grain for Green′(GFG) project to restore the eco-environment of the Loess Plateau since 1999. With the GFG project subsidy approaching the end, it is concerned that farmers of fewer subsidies may reclaim land again. Thus, ′Gully Land Consolidation Project′(GLCP) was initiated in 2010. The core of the GLCP was to create more land suitable for farming in gullies so as to reduce land reclamation on the slopes which are ecological vulnerable areas. This paper aims to assess the effect of the GLCP on soil erosion problems by studying Wangjiagou project region located in the central part of Anzi valley in the middle of the Loess Plateau, mainly using the revised universal soil loss equation(RUSLE) based on GIS. The findings show that the GLCP can help to reduce soil shipment by 9.87% and it creates more terraces and river-nearby land suitable for farming which account for 27.41% of the whole study area. Thus, it is feasible to implement the GLCP in places below gradient 15°, though the GLCP also intensifies soil erosion in certain places such as field ridge, village land, floodplain, natural grassland, and shrub land. In short, the GLCP develops new generation dam land and balances the short-term and long-term interests to ease the conflicts between economic development and environmental protection. Furthermore, the GLCP and the GFG could also be combined preferably. On the one hand, the GFG improves the ecological environment, which could offer certain safety to the GLCP, on the other hand, the GLCP creates more farmland favorable for farming in gullies instead of land reclamation on the slopes, which could indirectly protect the GFG project.

Integrated Geophysical and Geotechnical Investigations for Earth Dam along Dansak River, Upper Shemankar River Basin, Jos Plateau, Central Nigeria

A total of 60 VES （geo-electrical resistivity soundings） and ten exploratory core holes （boreholes） were carried out along the axis of a proposed earth dam site as part of an overall geotechnical investigation for the design and construction of an earth dam along Dansak River, Shemankar River Basin, Jos Plateau, Nigeria. The geophysical interpretation revealed four to five geo-electric layers corresponding to lithologic units （1） topsoil from 0-2 m with a resistivity value of 〈 100-320 ohm-m, （2） weathered/slightly weathered basalt fi＇om 0.6 m to 20 m characterized by resistivity value of 27-130 ohm-m, followed by （3） basalt/fractured basalts with resistivity value of 130-400 ohm-m and （4） the basement rocks with resistivity value 〉 320 ohm-m to 3,021 ohm-m. Exploratory borehole drilling encountered a series of lithologic units viz： overburden （clay, silt and sand） weathered basalt, slightly weathered basalt, fresh/fractured basalts, weathered migmatite and migmatites/migmatite gneiss. Exploratory core analysis in terms of CR （core recovery） and RQD （rock quality designation） revealed an average of 70%-90% and 75%-90%, respectively. Lugeon test gave Lugeon values of 1-5 for the ten core holes. However, fractures with Lugeon value from 〉 5-15 lugeon were encountered on borehole numbers BH 1, 7, 8, 9 and 10. Grouting is recommended to seal this shallow to medium depth （0-15 m） fractures to reduce or eliminate possible seepage when the dam is constructed. The rock mass index grading for the dam axis ranges from good to excellent.

Livelihood Diversification as an Adaptation Approach to Change in the Pastoral Hindu-Kush Himalayan Region

Migratory livestock raising has been one of the most important livelihood options for people residing in high mountain areas and has made a significant contribution to the economy of the Hindu Kush Himalayan(HKH) region, both in terms of supporting households and in export earnings. However, in recent decades, changes in the socioeconomic situation and increasing climate variability have led to a need to enhance adaptation by building the resilience of local socio-ecological systems, including economic diversification and sustainable management of natural resources. Based on semistructured interviews with pastoral communities in six countries within the pastoral HKH region, this paper discusses the situation, trends and driving forces behind the diversification of pastoral livelihood. For internal diversification the study highlights the need for enhancement of pastoral livelihoods through value-adding activities in the pastoral sectors. For external diversification changes on policy changes are needed to support free out-migration, market exploitation, and multiple resource use. Finally the paper highlights the role of education in determining household adaptation strategies in the face of various socio-ecological pressures and recommends integrating innovative and indigenous knowledge to develop appropriate methods for risk management and resource management in the pastoral HKH region.

A COM-based Framework for Management,Analysis and Visualization of Large Scope Digital Elevation Models

This paper presents a component object model (COM) based framework for managing, analyzing and visualizing massive multi-scale digital elevation models (DEMs). The framework consists of a data management component (DMC), which is based on RDBMS/ORDBMS, a data analysis component (DAC) and a data render component (DRC). DMC can manage massive multi-scale data expressed at various reference frames within a pyramid database and can support fast access to data at variable resolution. DAC integrates many useful applied analytic functions whose results can be overlaid with the 3D scene rendered by DRC. DRC provides view-dependent data paging with the support of the underlying DMC and organizes the potential visible data at different levels into rendering.

Ship Waste Management in the Port of Igoumenitsa, Greece

Port of Igoumenitsa in Greece is one of the most important Ports in European Union and enjoys a privileged position being located at the starting point of Egnatia Motorway The Port is one of the largest passenger ports in the East Mediterranean Sea basin, which, handles around 1,000,000 passengers per year for international destinations. The paper investigates current waste management and disposal options for ship generated waste and the associated impact of the waste for port. Data about the ship traffic were provided by the Port Authority and about the amount and characteristics of the wastes by the contractors for the disposal of the ship generated waste. It was concluded that all vessels should be encouraged to use the reception facilities and should pursue a waste reduction strategy and the port authority to provide adequate recycling facility. An electronic recording data system has to be adopted for better evaluation of the performance of the system. This system must record the deliveries for every ship in the port, the amount and the type of wastes are generated. Also must provide information about the maximum storage capacity of waste on board and about management of waste treatment options by the ships.