Traditional management of a hillside agroecosystem in Tlaxcala, Mexico: An ecologically based maintenance system

Traditional agricultural systems are increasingly being recognized as important examples of ecologically sustainable production methods and as such deserve agroecological attention. In a study of terrace agriculture in Tlaxcala, Mexico, the authors identify several management features which have been used for as long as three thousand years. The theoretical approach employs the notion of open versus closed agroecosystems for examining soil and water management, species diversity, and nutrient cycling. In the traditional system, conservation of existing resources is the distinctive feature whereas, with modern techniques, the emphasis is on replacement. The most distinctive feature of the Tlaxcalan agroecosystem is the terrace/cajete complex which serves to contain heavy downpours and trap eroded soil, ensures diversity of plant species, and traps and concentrates nutrients. The functioning of this traditional system is endangered by new management strategies that have responded to external political, economic and social pressures for change. This article discusses the ecological repercussions of these new practices and suggests ways that appropriate elements may be integrated to promote the sustainability of food production.