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ABSTRACT One of the most important protected areas of Mexico where payment for environmental services has been introduced is the Monarch Butterfly Biosphere Reserve (MBBR) in the state of Michoacán. This paper presents a spatial and chronological portrait of land degradation in the Angangueo sector of the MBBR; land-use changes over about four decades are analysed by assessing data for the years 1971, 1994, 2009 and 2010. A significant landsliding episode occurred in February 2010, when several debris flows affected the area of the Reserve, causing 16 deaths, substantial damage to roads, electricity and the water supply system, and indirect consequences for crop production, cattle farming and tourism. Changes in land cover between 2009 and 2010 were assessed to determine the likely role of deforestation on landsliding as well as to estimate the significance of landslides in land-use change. The former was demonstrated because digital photo interpretation and field observations revealed that the debris flows began in deforested zones. The findings also indicated that 54·57 ha of forest were either degraded or destroyed as a consequence of landslides and winds. In the Angangueo basin, the rate of land-cover change from 1971 to 1994 was 0·96 per cent, from 1994 to 2009 it had decreased to 0·91 per cent, but for the year 2010 had increased to 0·97 per cent, mainly as a result of the landsliding episode of February 2010. The MBBR has experienced a relatively significant amount of land-cover change over the past four decades, although deforestation has not increased as severely as in other areas of Mexico. This suggests that payments for environmental services can reduce the human-induced deforestation; however, mitigation of the impact caused by hazards in forest areas should be sought from a perspective that includes disaster theory and geodiversity. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Landslides disasters in Mexico caused more than 3500 deaths between 1935 and 2006. Such disasters have been mainly associated to intense precipitation events derived from hurricanes, tropical storms and their interactions with cold fronts, although earthquake triggered landslides have also occurred to a lesser extent. The impact of landsliding in Mexico is basically determined by the geomorphic features of mountain ranges and dissected plateaus inhabited by vulnerable communities. The present contribution provides a comprehensive temporal assessment of historical landslide disasters in Mexico. Moreover, it aims at exploring the future directions of risk management and disaster prevention, in order to reduce the impact of landslides on populations as a result of climatic change, urban sprawl, land use change and social vulnerability. [ABSTRACT FROM AUTHOR]

Abstract: This study examines mass movement associated with land use change, particularly deforestation, from multiple perspectives. The significance of such understanding is related to the degree of impact landsliding may cause on human settlements and economic activities, and on forest ecosystems. In this paper, the distribution of hillslope instability in the Sierra Norte, Puebla, Mexico is addressed by means of a diachronic analysis, which involves the development of vegetation indexes, as well as vegetation fragmentation derived from Landsat-5 (TM) and Landsat-7 (ETM+) satellite images from 1989 and 1999, respectively. The time period was chosen to compare vegetation cover conditions prior and after the extreme October 1999 rainfall event that triggered hundreds of slope failures in the study area. Results suggested there was a significant vegetation reduction from 1989 to 1999, which was strongly expressed by an increase of 809 km2 of bare surfaces. Additionally, areas with highest vegetation density (91–100%) decreased considerably, from 1245 to 363 km2, resulting in a net vegetation reduction of 70%. Furthermore, it was possible to highlight that landslide concentration was much higher on surfaces that were bare and had low vegetation density (0–50%), representing 85% of hillslope instability, than on surfaces having a greater density of vegetation cover. Land use change and land degradation are precursors to environmental hazards, such as mass movement events, that pose serious threats to regional population distributions and economic vitality. [Copyright &y& Elsevier]

Rainfall-induced landsliding represents a major hazard in Mexico. About 200 municipalities in the states of Puebla, Veracruz and Hidalgo were affected by flooding and mass movement processes that resulted from a tropical depression from the Atlantic Ocean in October 1999. Hundreds of slope failures were triggered by intense precipitation, which in some localities reached 420 mm during a 24-h period. According to official information, 263 people died and 1 475 654 inhabitants were affected by flooding and landsliding.Rainfall event and cycle coefficient defined and the ratios between event and antecedent rainfalls, respectively, and the mean annual rainfall are summed to give a total coefficient. For landslide-triggering rainfalls in the Sierra Norte, values for the total coefficient of 0.8 and 0.4 for beginning and end of the wet season, respectively, appear to be important.In addition, a hazard assessment was carried out through the development of a landslide susceptibility indicator. This was elaborated by using aerial photographs, integrating field observations and the coupling of slope instability analysis within a digital elevation model framework. Field validation indicated that this approach provides a good representation of shallow translational failures; 81% of the observed landslides were satisfactorily predicted as potential unstable zones. Results suggested that this type of DEM-based hazard assessment can be extremely valuable not only after, but also before any landslide-related event, so that disaster preparedness and planning could be adequately structured. [Copyright &y& Elsevier]