Soils (1) Sewage--Purification (1) Refuse and refuse disposal (1) Profit (1) Production (Economic theory) (1) Peace (1) Metabolism (1) Families (1) Corn (1) Suelo (1) Residuos (1) Estudio (1) Zonas rurales (1) Producción (1) Beneficios (1) Metabolismo (1) Paz (1) Suelos (1) Familias (1) Maíz (1) Aguas residuales--Tratamiento (1) génération (1) production (1)