Development of a livestock population model for winter disaster risk assessment in Mongolia

Abstract:

Mongolia has historically experienced winter disasters, called dzuds in Mongolian, and posed serious damages in the livestock sector. For example, a series of dzuds in 2000-2002 killed more than 11 million livestock, and that in 2010 killed over 10 million livestock. For effective risk assessment of this disaster, we are now developing a livestock population model. In this model, livestock die when their weights are very low, and the weights are calculated by energy balance. The energy intake is calculated as a product of potential and relative intake. Potential intake is determined by weight, and relative intake is a function of biomass amount in surrounding grassland. In winter, accessibility to grass (function of snow depth, air temperature, and wind speed) is also considered. On the other hand, energy consumption is the sum of those by thermoregulation and grazing activity. Energy loss by thermoregulation is a function of weight and climatic conditions (at present air temperature and wind speed). Energy loss by grazing activity is calculated from biomass density and condition. We plan to validate and calibrate this model by using data in Mongolian grassland, and then to use for dzud risk assessment of that country.