scholarly journals Impact of mapping errors on the reliability of landslide hazard maps

2002 ◽  
Vol 2 (1/2) ◽  
pp. 3-14 ◽  
Author(s):  
F. Ardizzone ◽  
M. Cardinali ◽  
A. Carrara ◽  
F. Guzzetti ◽  
P. Reichenbach

Abstract. Identification and mapping of landslide deposits are an intrinsically difficult and subjective operation that requires a great effort to minimise the inherent uncertainty. For the Staffora Basin, which extends for almost 300 km2 in the northern Apennines, three landslide inventory maps were independently produced by three groups of geomorphologists. In comparing each map with the others, large positional discrepancies arise (in the range of 55–65%). When all three maps are overlain, the locational mismatch of landslide deposit polygons increases to over 80%. To assess the impact of these errors on predictive models of landslide hazard, for the study area discriminant models were built up from the same set of geological-geomorphological factors as predictors, and the occurrence of landslide deposits within each terrain-unit, derived from each inventory map, as dependent variable. The comparison of these models demonstrates that statistical modelling greatly minimises the impact of input data errors which remain, however, a major limitation on the reliability of landslide hazard maps.

2017 ◽  
Vol 21 (9) ◽  
pp. 4573-4589 ◽  
Author(s):  
Liang Gao ◽  
Limin Zhang ◽  
Mengqian Lu

Abstract. Rainfall is the primary trigger of landslides in Hong Kong; hence, rainstorm spatial distribution is an important piece of information in landslide hazard analysis. The primary objective of this paper is to quantify spatial correlation characteristics of three landslide-triggering large storms in Hong Kong. The spatial maximum rolling rainfall is represented by a rotated ellipsoid trend surface and a random field of residuals. The maximum rolling 4, 12, 24, and 36 h rainfall amounts of these storms are assessed via surface trend fitting, and the spatial correlation of the detrended residuals is determined through studying the scales of fluctuation along eight directions. The principal directions of the surface trend are between 19 and 43°, and the major and minor axis lengths are 83–386 and 55–79 km, respectively. The scales of fluctuation of the residuals are found between 5 and 30 km. The spatial distribution parameters for the three large rainstorms are found to be similar to those for four ordinary rainfall events. The proposed rainfall spatial distribution model and parameters help define the impact area, rainfall intensity and local topographic effects for landslide hazard evaluation in the future.


2011 ◽  
Vol 8 (6) ◽  
pp. 10589-10633
Author(s):  
G. Göransson ◽  
M. Larson ◽  
D. Bendz ◽  
M. Åkesson

Abstract. Landslides of contaminated soil into surface water represent an overlooked exposure pathway that has not been addressed properly in existing risk analysis for landslide hazard, contaminated land, or river basin management. A landslide of contaminated soil into surface water implies an instantaneous exposure of the water to the contaminated soil, dramatically changing the prerequisites for the mobilisation and transport of pollutants. In this study, an analytical approach is taken to simulate the transport of suspended matter released in connection with landslides into rivers. Different analytical solutions to the advection-dispersion equation (ADE) were tested against the measured data from the shallow rotational, retrogressive landslide in clayey sediments that took place in 1993 on the Göta River, SW Sweden. The landslide encompassed three distinct events, namely an initial submerged slide, followed by a main slide, and a retrogressive slide. These slides generated three distinct and non-Gaussian peaks in the online turbidity recordings at the freshwater intake downstream the slide area. To our knowledge, this registration of the impact in a river of the sediment release from a landslide is one of the few of its kind in the world, and unique for Sweden considering the low frequency of landslide events, making it highly useful for evaluating how appropriate the ADE is to describe a landslide into surface water. The results yielded realistic predictions of the measured concentration variation, after proper calibration. For the three individual slides it was estimated that a total of about 0.6% (515 000 kg) of the total landslide mass went into suspension/was suspended and was transported downstream. This release corresponds to about 1 to 2% of the annual suspended sediment delivery for that river stretch. The studied landslide partly involved an industrial area and by applying the analytical solution for the transport of metals in the sediments it was found that landslides have the possibility to release a significant amount of pollutants if large contaminated areas are involved. However, further studies are needed to develop more detailed descriptions of the transport processes. There is also a need to increase the knowledge on possible environmental consequences in the near and far field, in a short and long-time perspective. Finally, the risk for the release of pollutants should not be neglected in landslide hazard and risk assessment.


2013 ◽  
Vol 1 (2) ◽  
pp. 957-1000 ◽  
Author(s):  
M. Fressard ◽  
Y. Thiery ◽  
O. Maquaire

Abstract. The objective of this paper is to assess the impact of the datasets quality for the landslide susceptibility mapping using multivariate statistical modelling methods at detailed scale. This research is conducted in the Pays d'Auge plateau (Normandy, France) with a scale objective of 1/10000, in order to fit the French guidelines on risk assessment. Five sets of data of increasing quality (considering accuracy, scale fitting, geomophological significance) and cost of acquisition are used to map the landslide susceptibility using logistic regression. The best maps obtained with each set of data are compared on the basis of different statistical accuracy indicators (ROC curves and relative error calculation), linear cross correlation and expert opinion. The results highlights that only high quality sets of data supplied with detailed geomorphological variables (i.e. field inventory and surficial formations maps) can predict a satisfying proportion of landslides on the study area.


2022 ◽  
Vol 7 (2) ◽  
pp. 173-184
Author(s):  
Ani Apriani ◽  
Bayurohman Pangacella Putra

The occurrence of landslides can not be separated from conditions that are prone to landslide movements such as steep slopes and high rainfall. The occurrence of landslides is also exacerbated by the indiscipline of the community in using land according to its function, which is called land conversion which can be a trigger factor for landslides. Conducting research on land use change is important to see the impact caused by human activities. The purpose of this study was to analyze the effect of land conversion on landslide hazard levels in Samigaluh District, Kulon Progo Regency. The method in this research was descriptive quantitative using primary data, namely field surveys and secondary data collection. The steps on this research were conducting field observations about the occurrence of land conversion and then retrieving level of landslide hazard at the observation point of land use change. Data analysis was performed using ordinal logistic regression. The result of the analysis showed that the p value (0.036) <0.05 which meant H0 was rejected. Thus, at the 95% confidence level it could be said that the variable of land use change affected the level of landslide hazard in Samigaluh District, Kulon Progo Regency. This output could be considered for the community to use the land according to its function.  Key words: Land Function Change; Landslide; Ordinal


Author(s):  
Alev Elçi ◽  
Hüseyin Yaratan ◽  
A. Mohammed Abubakar

Higher educational institutions exert great effort to improve educational quality and effectiveness to cope with digital challenges in education. The impact of COVID-19 on education highlighted the importance of the achievement of sustainability in higher education. To overcome many of these challenges, faculty members need sustained professional development infrastructure embracing individual and institutional dimensions for enhancing educational qualifications. In this study, a quantitative method was employed to explore goals, individual needs, and institutional expectations of faculty in an international university in a developing country. The obtained survey data were analyzed using descriptive and non-parametric statistics (i.e., Kendall's coefficient of concordance, Kruskal–Wallis test, and Mann–Whitney U test). The findings demonstrate that the preferred goals of the faculty are found as developing skills in disciplinary knowledge, teaching and learning, and research. To achieve these goals, they favor certain capacity building activities and support services. Findings reflect the faculty's positive attitude towards multidimensional development, thus opening up to the global knowledge-based community. This study contributes to the existing literature as a pilot study to identify that faculty professional development needs are in line with student academic support.


Author(s):  
Barbara D. Klein

Data stored in organizational databases have a significant error rate. As computerized databases continue to proliferate, the number of errors in stored data and the organizational impact of these errors are likely to increase. The impact of data errors on business processes and decision making can be lessened if users of information systems are able and willing to detect and correct data errors. However, some published research suggests that users of information systems do not detect data errors. This paper reports the results of a study showing that municipal bond analysts detect data errors. The results provide insight into the conditions under which users in organizational settings detect data errors. Guidelines for improving error detection are also discussed.


2001 ◽  
Vol 33 (4) ◽  
pp. 603-622 ◽  
Author(s):  
PAULA GRIFFITHS ◽  
ANDREW HINDE ◽  
ZOË MATTHEWS

Using cross-sectional, individual-level survey data from Maharashtra, Tamil Nadu and Uttar Pradesh collected under the Indian National Family Health Survey programme of 1992–93, statistical modelling was used to analyse the impact of a range of variables on the survival status of children during their first 2 years of life. Attention was focused on the potential impact of the mother’s autonomy. The strongest predictors of mortality were demographic and biological factors, breast-feeding behaviour, and use and knowledge of health services. Variables that can be interpreted as being related to maternal autonomy, such as the presence of a mother-in-law in the household, did not have a significant direct effect on child survival at the individual level, and their indirect effects were very limited.


2002 ◽  
Vol 2 (1/2) ◽  
pp. 57-72 ◽  
Author(s):  
M. Cardinali ◽  
P. Reichenbach ◽  
F. Guzzetti ◽  
F. Ardizzone ◽  
G. Antonini ◽  
...  

Abstract. We present a geomorphological method to evaluate landslide hazard and risk. The method is based on the recognition of existing and past landslides, on the scrutiny of the local geological and morphological setting, and on the study of site-specific and historical information on past landslide events. For each study area a multi-temporal landslide inventory map has been prepared through the interpretation of various sets of stereoscopic aerial photographs taken over the period 1941–1999, field mapping carried out in the years 2000 and 2001, and the critical review of site-specific investigations completed to solve local instability problems. The multi-temporal landslide map portrays the distribution of the existing and past landslides and their observed changes over a period of about 60 years. Changes in the distribution and pattern of landslides allow one to infer the possible evolution of slopes, the most probable type of failures, and their expected frequency of occurrence and intensity. This information is used to evaluate landslide hazard, and to estimate the associated risk. The methodology is not straightforward and requires experienced geomorphologists, trained in the recognition and analysis of slope processes. Levels of landslide hazard and risk are expressed using an index that conveys, in a simple and compact format, information on the landslide frequency, the landslide intensity, and the likely damage caused by the expected failure. The methodology was tested in 79 towns, villages, and individual dwellings in the Umbria Region of central Italy.


Proceedings ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 3
Author(s):  
Felipe Antonio Moura Miranda ◽  
Paulo Cardieri

The energy consumption in wireless sensor networks is the critical concern of different studies, especially because of the great effort, or even the impossibility, to replace the battery of their motes. Consequently, it is fundamental to investigate and evaluate the energy spent by every individual task executed by the motes in order to provide an efficient use of their batteries. In this work, we employ different metrics to present a thorough study of how the use of multiple transmission power levels affects multihop wireless sensor networks. This work is motivated by the current employment of the multiple transmission power levels, on both academic works and commercial solutions, which is a novel feature of some radio transceivers commonly used in wireless sensor network motes. Aiming for reliable and extensive analysis, this study employs simulations in different scenarios and models of commonly employed electronic components. The contribution of this works is a detailed investigation of the impact caused by the use of different transmission power levels employing different metrics, offering a wide perspective on the subject. In general, the results of this study indicate that the use of multiple power levels grants both positive and negative results, according to the scenario and metrics analyzed.


Sign in / Sign up

Export Citation Format

Share Document