Simulated dynamics of net primary productivity (NPP) for outdoor livestock feeding coefficients driven by climate change scenarios in México

Abstract

In this paper the concept of Net Primary Productivity (NPP) is used as a way to estimate the capacity of the ecosystem to produce dry matter which may be available for livestock to meet the forage requirements. The method allows the simulation of the possible impact on NPP and dry matter (DM), under climate change conditions observable for the country in a given time horizon. The concept was also used for current coefficients of rangeland and under current climate change scenarios, thus allowing to observe possible changes on the required surface for a sustainable cattle nutrition. It was found that México has NPP values ranging from 0 to 50 000 kgDM / ha / year. Dry matter is in the range that goes from 0 to 25 000 kgDM / ha / year. The coefficients of rangeland for the current scenario do not change significantly compared to those presented by COTECOCA, the official body determining such values. The states that present a greater impact due to current conditions under climate change scenarios were Baja California, Baja California Sur, Coahuila, Colima, Jalisco, Nuevo León, Puebla, Querétaro, San Luis Potosí, Sonora, Tamaulipas, Veracruz and Yucatán; this group will also have changes in its coefficients of rangeland in the future. Considering all of the above we discuss the implications that can be observed and we analyze the alternatives proposed by the federal government for the country’s livestock sector.