An integrated agro-ecosystem
In the Ziro Valley of Arunachal Pradesh, at an altitude around 1,570 meters, the Apatani people practice a unique form of agriculture that integrates rice, fish, and forestry. This system, developed over centuries, functions without farm animals or modern machinery, relying entirely on human labor and a deep understanding of the local ecology. The valley floor is meticulously terraced into plots for wet rice cultivation. These fields are irrigated by a gravity-fed network of bamboo and wooden pipes that divert water from mountain streams. This complex system maintains a constant water level ideal for both rice and fish.
The core of the system is the symbiotic relationship between rice and fish, a practice known locally as Aji-Nguyi. Shortly after transplanting rice seedlings, farmers introduce fingerlings of fish, primarily Common Carp (Cyprinus carpio), into the flooded paddies. The fish thrive on plankton, algae, and insect pests that would otherwise harm the rice. Their movement aerates the soil, and their excrement is a natural fertilizer, boosting rice productivity by an estimated 10-15%. This method can yield an additional 350 to 500 kilograms of fish per hectare each season. To ensure the fish survive when water levels are low, a small ditch or refuge area is dug into each paddy.
Sustainable land use
The Apatani system extends beyond the paddy fields. The earthen bunds, or partitions between plots, are not wasted space. Here, the Apatani cultivate finger millet (Eleusine coracana), adding another crop to the harvest. This tri-cropping pattern of rice, fish, and millet ensures year-round productivity and food security. Nutrient cycling is important to the system's longevity. Organic waste from villages—including pig and poultry manure, ash, and composted weeds—is channeled with irrigation water into the fields, constantly replenishing soil fertility. This has allowed for continuous cultivation without depleting the soil.
Surrounding the valley, the Apatani manage groves of bamboo and pine. They cultivate specific species like blue pine (Pinus wallichiana) and a type of bamboo known as bije (Phyllostachys bambusoides). These forests prevent soil erosion on the hillsides, protect the watersheds that feed the irrigation channels, and provide resources like timber for construction and fuel. The Apatani Cultural Landscape was added to UNESCO's Tentative List for World Heritage Sites in 2014 for its high productivity and unique method of preserving the ecology.