Agricultural utilization of sludge from rural sewage system, 1: Influence on growth and yield of crops and on soil by application of raw-sludge

cadmio cadmium cinc crecimiento croissance crop yield crops cultivos growth lodos residuales plant response plante de culture rendement des cultures rendimiento de cultivos respuesta de la planta rural areas sewage sludge sewerage soil treatment traitement du sol tratamiento del suelo zinc zonas rurales zone rurale