Evaluation of the risks to landslides within the Matanzas watershed, Polochic river, Guatemala

Tesis (M. Sc) -- CATIE, Turrilaba (Costa Rica),2001La cuenca del r?o Polochic en Guatemala ha sufrido las consecuencias de desastres, por esta raz?n durante el primer semestre del 2001 se evalu? la vulnerabilidad y el riesgo en la subcuenca Matanzas, con el objeto de identificar niveles y ?reas con mayor grado de vulnerabilidad y riesgo a desastres, y proponer los mecanismos adecuados para implementar planes de reducci?n y mitigaci?n de la vulnerabilidad. En las evaluaciones se emplearon indicadores de vulnerabilidad y amenazas, los cuales se integraron adaptando el programa ALES (Automated Land Evaluation System). Se logr? identificar y seleccionar las comunidades con mayores niveles de vulnerabilidad y riesgo a desastres. Se tom? como base la formula general del riesgo (vulnerabilidad x amenazas / preparaci?n), y se consider? entre la preparaci?n, la influencia que ejerce el factor humano por las actividades productivas que se realizan en la subcuenca y sus implicaciones en aumentar o mantener los niveles de vulnerabilidad y riesgo. Los resultados reflejan que de las 101 comunidades evaluadas en la subcuenca, 25 comunidades presentan alta vulnerabilidad y 32 alto riesgo, as? mismo, 59 muestran mediana vulnerabilidad y 53 riesgo medio, mientras que 16 comunidades muestran baja vulnerabilidad y 17 bajo riesgo. Adem?s, se identificaron los indicadores con mayor influencia, algunos de car?cter social (nivel educativo, v?as de comunicaci?n,) y otros de tipo ambiental (intensidad de uso de la tierra). Con base en los factores que afectan la vulnerabilidad y riesgo, se formularon estrategias y l?neas de acci?n, a fin de reducir los efectos de los eventos que causen desastres y contribuir con el desarrollo de las comunidades de la subcuenca. The Polochic river watershed in Guatemala has suffered from numerous disasters. During the first quarter of 2001, the vulnerability and risks associated with the Matanzas sub-basin was evaluated, with the objective of identifying levels and areas of greatest vulnerability and risk to disasters, and to propose mechanisMON for the implementation of plans for the reduction and mitigation of the vulnerability. In the evaluations, vulnerability and risk indicators were utilized, and were integrated by adapting the ALES (Automated Land Evaluation System) program. Communities with the greatest levels of vulnerability and risk to disasters were identified. We used the formula for risk assessment (vulnerability x threats / preparation) as the basis for the evaluation, and included within the context of preparation, the influence exerted by human activity in the production areas within the sub-basin and its effect on the levels of vulnerability and risk. The results show that of the 101 communities evaluated in the sub-basin, 25 communities exhibit high vulnerability and 32 high risk. At the same time, 59 show medium vulnerability and 53 medium risk, while 16 show low vulnerability and 17 low risk. Also identified were indicators with high influence, some of a social nature (education level, means of communication) and others of an environmental type (land use intensity). Using factors affecting vulnerability and risk as the basis, strategies and action plans were formulated to reduce the effects of disasters and contribute to the development of the communities within the sub-basin