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Vulnerability and resilience are two crucial attributes of social-ecological systems that are used for analyzing the response to disturbances. We assess these properties in relation to agroecosystem buffer capacity and adaptive capacity, which depend on the 'window of opportunities' of possible changes in terms of selected performance indicators, i.e., the solution space. The vulnerability of the system was quantified as the distance of performance indicators between original and disturbed systems. The buffer capacity was derived from the size of the solution space that could be obtained after reconfiguration of farm components (crops, animals, fertilizers, etc.) that were present on the original farm, whereas the assessment of adaptive capacity was derived in a similar way, but after allowing innovation by introducing new components to the farm. To illustrate the approach, we applied these concepts to two dairy farms in Northwest Michoacán, Mexico. After a disturbance resulting in a fodder maize yield decline, both economic profitability and soil organic matter inputs were reduced. The scope for recovery was different between the farms, but the projected improvements in profitability and organic matter inputs would require considerable changes in the farm configurations, and thus flexibility in farm management. High resilience requires a farmer with the managerial ability to make the required changes to move through the proposed solution space. The approach we present here offers a generic quantitative assessment of vulnerability and resilience concepts, based on a combined assessment of the social and ecological dimensions of agroecosystems.

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El objetivo fue revisar, con base en publicaciones predominantemente recientes, el conocimiento sobre los componentes del comportamiento de ingestión (CI) de vacas que pastorean en clima templado, y su relación con las características de las praderas que regulan el consumo diario de forraje (CF). Los componentes del CI que median el CF son masa de bocado (MB, g MS bocado-1), tasa de bocados (TB, bocados min-1), tasa de consumo (TC, g MS min-1) y tiempo de pastoreo (TP, min día-1). La masa, altura y densidad del forraje de las praderas afectan la MB y consecuentemente, el CF. La altura de la pradera se relaciona con los componentes del CI y es útil para evaluar el CF. Con base en estudios en praderas templadas en estado vegetativo, se destaca que el CF de vacas aumenta con incrementos en altura de la pradera, porque cosechan bocados de mayor MB, lo que les permite obtener altas TC. Pero, hay evidencia de que la TC puede disminuir en praderas demasiado altas; para procesar bocados más grandes, las vacas reducen su TB y ejecutan mayor cantidad de movimientos mandibulares compuestos y de masticación. Por el contrario, en praderas cortas las vacas aumentan su TB y TP, para remediar la reducción en la TC debida a la cosecha de bocados de menor peso, aunque esto no compensa completamente la disminución de TC. Por lo anterior, para mantener altas TC las vacas no deben ser forzadas a consumir forraje a altas intensidades de pastoreo.