Sustainability indicators of the Hanuno Mangyan [Philippines] indigenous agroforestry systems

The Hanunuo Mangyans practice three production systems: swidden or kaingin, multistorey, and home gardens. Swidden farming was the most practiced system but the least ecologically sound. Rice and corn were the major crops planted. Other crops interplanted included banana, cassava, sugarcane, and root crops. These crops were randomly planted and thus compete with the rice and corn for soil nutrients, water and sunlight resulting to low yields. Fallowing was practiced whenever the farmer noticed that the soil was no longer fertile. In multistorey farms, the upper canopy had mango, banana, anahaw, and anuling. The lower canopy was planted to coconut, the middle canopy was dominated by pineapple with some ipil-ipil at the edges. The multistorey system was found the most ecologically sound in terms of soil fertility maintenance. The erosion rates of the farming systems exceeded the tolerable range of 10-12 t/ha per year which was not sustainable in the long run. The Hanunuo Mangyans used only flower indecers for mangoes. They did not use any pesticide and commercial inorganic fertilizers. The positive impact of this practice was pollution-free soil which was ecologically-sound in the long run. The negative impacts included less soil fertility and slow nutrient build-up; longer fallow period to regain soil fertility; and low crop yield. Mangyans still observed rituals in planting and harvesting. The swidden farmers had no technical knowledge in crop production. However, most of them expressed the desire to acquire knowledge on increasing this crop yield