Assessing landslide hazard in GIS: a case study from Rasuwa, Nepal

A slope stability analysis on a regional scale is presented for the northern part of the Rasuwa district in Nepal, covering 409 km². A physically based slope stability model coupled to a simplified groundwater flow model was used to estimate soil wetness, and safety maps were generated for three steady state and two quasi-dynamic conditions. The results show that only about half of the soils are unconditionally stable, characterised by slopes smaller than 22°. Some 7% of the study area is prone to failure under completely saturated conditions, where the slopes exceed 30° and the land-use is predominantly agricultural. Some deficiencies in the model are discussed, but nevertheless the study shows that based upon relatively coarse and limited data, useful landslide hazard information on a regional scale can be obtained.     

Identifying regional landscapes for conservation planning: a case study from KwaZulu-Natal, South Africa

The application of landscape ecology in conservation biology has rarely occurred in the context of defined landscapes. Conservation planning has focussed on representation of species diversity patterns and assumed that ecosystems, landscapes and their associated processes will be equally protected. The long-term persistence of biodiversity in the face of land transformations and global change requires the representation and retention of all elements of biodiversity. This biodiversity includes landscapes, and the landscape structure and processes that maintain patterns of biodiversity. We developed a method of classifying landscapes for the KwaZulu-Natal province of South Africa. The process entailed the use of 1 km² grid data from climate and terrain databases. Principal components analysis coupled with a cluster classification method and spatial overlay techniques were used to identify two hierarchical levels of landscapes. Validation analysis showed that landscapes are identifiable with a classification accuracy of 86.8%. The derived landscapes can be combined separately with data on vegetation and soil to describe landscape ecosystems that potentially differ in species composition, successional dynamics, and potential productivity. The surrogate use of the landscapes in conjunction with other strategic data, for the identification of priority conservation areas, is demonstrated.     

A method for quick assessment of earthquake-triggered landslide hazards: a case study of the Mw6.1 2014 Ludian,China earthquake

Rapid assessment of the distribution of earthquake-triggered landslides is an important component of effective disaster mitigation. The effort should be based on both seismic landslide susceptibility and the ground shaking intensity, which is usually measured by peak ground acceleration (PGA). In this paper, we address this issue by analyzing data from the Mw6.1 2014 Ludian, China earthquake. The Newmark method of rigid-block modeling was applied to calculate the critical acceleration of slopes in the study area, which serve as measurement of slope stability under seismic load. The assessment of earthquake-triggered landslide hazard was conducted by comparing these critical accelerations with the distribution of known PGA values. The study area was classified into zones of five levels of landslide hazard: high, moderate high, moderate, light, and very light. Comparison shows that the resulting landslide hazard zones agree with the actual distribution of earthquake-triggered landslides. Nearly 70% of landslides are located in areas of high and moderately high hazard, which occupy only 17% of the study region. This paper demonstrates that using PGA, combined with the analysis of seismic landslide susceptibility, allows a reliable assessment of earthquake-triggered landslides hazards. This easy-operation mapping method is expected to be helpful in emergency preparedness planning, as well as in seismic landslide hazard zoning.

     

Hydrogeological modelling to support urban planning in harbour areas: a case study from Horsens,Denmark

Bulletin of Engineering Geology and the Environment - Historically, industries were in harbour areas of cities for easy access to transportation of resources. Today, transforming former industrial...     

Effectiveness of siphon drainage method for landslide stabilization in a tropical volcanic hillslope: a case study of Cibitung Landslide,West Java,Indonesia

Bulletin of Engineering Geology and the Environment - An effort to implement a siphon drainage system requires a comprehensive knowledge of the factor affecting the performance of the drainage...     

大都市边缘农业旅游地区控规探索

城乡统筹发展为非常规城镇空间带来了发展良机,对这类地区的规划研究需要全方位的转变。本文首先梳理了近年来国内农业旅游地区规划的相关研究进展情况,继而以南京江心洲为例探讨了大都市边缘的农业旅游地区在规划方法和控制措施上创新的主要思路。     

A GIS-based multi-criteria decision making approach to forest conservation planning at a landscape scale: a case study in the Kinabalu Area, Sabah, Malaysia

This paper presents a geographic information system (GIS)-based multi-criteria decision making approach for forest conservation planning at a landscape scale. This approach enables decision makers to evaluate the relative priorities of conserving forest areas based on a set of preferences, criteria and indicators for the area. Compromise programming techniques are used to integrate the forest conservation priority maps of decision groups where a separation distance is calculated. A clustering analysis was applied to identify potential conservation areas as the basis of delineating potential new protected areas. The study was conducted in the Kinabalu area, Sabah, Malaysia where two polygons neighboring the Kinabalu Park were delineated. A group of 11 polygons totaling 2050 ha has also been detected in the western part of Kinabalu Park. The study recommends the inclusion of a forest polygon (359 ha) neighboring Kinabalu Park and another (4361 ha) to the west of the park as new protected areas. A green corridor linking the potential new protected areas and Kinabalu Park should also be constructed to facilitate animal movement and interaction. This study reveals that riparian vegetation is an important aspect to forest conservation and the legislation to protect riparian zones should be strengthened.     

Formation and evolution of a successive landslide dam by the erosion of river: a case study of the Gendakan landslide dam on the Lancang River,China

Bulletin of Engineering Geology and the Environment - A landslide dam located on the Lancang River in Southwest China was used as a case to study the landslide formation and evolution process...     

A new quality factor for the building stone industry: a case study of stone blocks,slabs, and tiles

In building stones, discontinuities, non-uniformity, and irregular shape are among the problems that reduce the quality of products. Stone blocks, slabs, and tiles are the main products of quarries and stone processing plants. Quantifying the quality is a key factor in valuation of these products. This paper proposes a quality factor formula to determine the quality of stone blocks (three-dimensional) and products from stone processing plants (two-dimensional). This factor, which shows the uniformity and esthetic index of a piece of stone, is determined based on the shape quality (α), number, size, and esthetic quality (β) of the pieces and the discontinuity factor (γ) that separates the pieces. The quality factor is defined in a way that each previously mentioned characteristic of a piece is involved in the quality factor formula calculation. The quality factor ranges between 0 and 1 and can be expressed as a percentage. The proposed quality factor was calculated for a number of different stone blocks, slabs, and tiles to examine the validity of the quality factor formula. The results showed that the shape quality is the most significant parameter in determining the quality of stone blocks in quarries. Moreover, in processing plant products the esthetic quality and the number of stone pieces in a product are the key factors for determination of their quality. The discontinuity factor is a parameter that reduces the quality of stone products significantly. Furthermore, the quality factor formula can be used as a convenient tool for classifying the products of quarries and stone processing plants.

     

Application of sliding seismic isolator to building structures considering cost,performance and inspection: a case study

Seismic isolation system (SIS) of building structures can lead to reduction of the structural response to earthquake ground motion and improvement of structural safety. This paper introduces a sliding seismic isolator with mass energy regulator springs (SSIM) as a SIS type, and presents the application procedure of the SSIM to an existing building structure considering the probability that the SIS application leads to cost–benefit, the seismic performance evaluation of the building structure and the efficient SIS inspection after earthquakes. Based on a decision tree considering the probability of earthquake occurrence during the service of a building structure and functionality of the SIS against earthquakes, cost–benefit from installing a SIS is formulated, and, probability that the SIS application leads to cost–benefit is estimated. In the seismic performance evaluation, the fundamental period and structural response acceleration to the horizontal ground motion of the building with the SSIM are assessed. Furthermore, the efficient SIS inspection plan after earthquakes is investigated based on the acceptance sampling. The existing building structure, information and communications technology center of Syiah Kuala University located in Banda Aceh, Indonesia is applied for the case study.     

GIS-based landslide hazard zonation: a case study from the Parwanoo area,Lesser and Outer Himalaya,H.P., India

GIS-based landslide hazard zonation has been carried out for a tectonically active region of the Himalayas, which is under pressure for rapid economic development. Thematic layers of slope, fault, geology, land use, flow accumulation, drainage and roads were prepared based on topographic maps, satellite imagery, published geological maps and ground truth. Five classes of landslide hazard were identified; 24% of the total area falls into the Very high or High hazard zones where 54% of the observed landslides were recorded.      

Analysis of landslide stability under seismic action and subsequent rainfall: a case study on the Ganjiazhai giant landslide along the Zhaotong-Qiaojia road during the 2014 Ludian earthquake,Yunnan, China

In a strong earthquake, not only a large number of coseismic landslides are triggered, but relaxation and cracks in the rocks and soils are induced, which make these rocks and soils vulnerable to instability during subsequent rainfall; thus, strong earthquakes always have long-term effects on landslides. The geo-hazards along the Zhaotong-Qiaojia road in the 2014 Ludian earthquake (Ms 6.5) of Yunnan Province, China, were investigated, and the Ganjiazhai giant landslide was chosen as a case study. First, using the limit equilibrium analysis and Newmark method, the critical seismic intensity of the landslide before the earthquake was evaluated. Secondly, the dynamic failure process of the landslide under the measured ground motion was simulated with the discontinuous deformation analysis method. Lastly, based on stress–seepage coupling analysis and precipitation data from Ludian meteorological station, the stability of the landslide during subsequent rainfall after the earthquake was predicted. The results show that the critical seismic intensity was within degrees VIII–IX, which is consistent with the results of the earthquake damage investigation. The dynamic failure process can be divided into four stages, and four scarps formed; the potential sliding zones during the subsequent rainfall were at the first scarp and the fourth scarp, and their critical rainfall amounts were 35–40 mm and 55–60 mm, respectively. In this paper, failure process simulation and stability prediction of the landslide before, during, and after the strong earthquake are presented, which provide analysis methods for the dynamic stability of landslides in the meizoseismal area.

     

Rapid assessment procedure to demarcate areas susceptible to earthquake-induced ground failures for environment management – a case study from parts of northeast India

Ground failures, such as landslide and the liquefaction of soil induced by earthquake and/or rainfall, not only pose a threat to human settlements but also degrade the environment. In order to be as prepared as possible, prior knowledge of the spatial distribution of areas vulnerable to these natural hazards and the critical locations for different degrees of risk is required. Information on the land cover, surface drainage, morphology, surface material, rock type, geological structure, lineament, rainfall and earthquake was used in developing a procedure to evaluate regions of potential ground failure. A case study from northeast India is presented to illustrate its value. Electronic Publication     

Use of multisensor and multitemporal geospatial datasets to extract the foundation characteristics of a large building: a case study

Bulletin of Engineering Geology and the Environment - The assessment of the ground conditions for large buildings is important because the results are sensitive to the ground conditions, especially...     

Site response analysis for the seismic improvement of a historical and monumental building: the case study of Augusta Hangar

Bulletin of Engineering Geology and the Environment - Eastern Sicily is very rich of historical buildings, but at the same time is one of the most seismically active areas of Italy. In particular,...     

Modification of rock stress factor in the stability graph method: a case study at the Alhada Lead-Zinc Mine in Inner Mongolia,China

Bulletin of Engineering Geology and the Environment - The stability graph is an empirical approach to predicting stope performance based on the geometric dimensions of stopes and the geotechnical...     

Communicative Approaches to Restoration Ecology: a case study from Dovre Mountain and Svalbard, Norway

Extensive damage to the vegetation cover in arctic and alpine landscapes has raised the question of restoration as a possible management strategy. Restoration is a goal-oriented activity, a technological undertaking wider than its parent science of ecology. Social science and planning concepts and methods are necessary to handle the value judgements implicit in restoration. It is argued that the notion of 'desired state' is a better reference point in defining restoration goals than the notion of 'original state'. Using qualitative methods, two areas with vulnerable arctic/alpine vegetation are investigated. Based on participants' statements, four possible scenarios or desired states for future management are constructed. The main focus in the scenarios is on participants' attitudes to restoration activity, and it is shown how these are influenced by participants' attachment to the area and their view of nature.     

Regional industrial production's spatial distribution and water pollution control: A plant-level aggregation method for the case of a small region in China

With fast economic growth, industrial water pollution has been a serious problem ubiquitously in China. More threatening is that lots of economic developing regions still strategically depend on fast industrialization, neglecting the relationship between production's spatial distribution and regional water environmental carrying capacity. As a small region, Deyang City is the objective case. We propose a plant-level aggregation method to estimate the spatial distribution of industrial water pollution pressure in the future five years. Based on discrete event simulation, newly added industrial projects' sizes and location choices (refer to industrial location theory) are regionally aggregated. COD (Chemical Oxygen Demand) emission into every river reach in the region is calculated respectively. In order to recover the water environmental function, the strategy aims at controlling emission within the carrying capacity of each river reach. And the strategy is assessed on its regional effects and spatial equity, from the perspective of government and industry. The results quantitatively show the diversified uncertain bounds of river reaches' COD adoptions which will aggravate the water pollution. And the pollution control strategy's effect indicates a large different level of spatial equity for industry and government respectively.