#1407 1971 · Subak irrigation networks (Bali) · Rice irrigation / common-pool farming
Bali's pests and water wars ended when farmers went back to scheduling crops at the temple
问题
Thousands of farmers share one watershed: synchronized fields breed pests, staggered fields breed water shortages
背景
Bali's rice terraces are fed by weirs and tunnels that thread whole watersheds together. Since at least the eleventh century, farmer associations called subak have managed the water through a nested network of water temples, whose rituals set the cropping calendar: fallow periods synchronized in patches large enough to starve pests, staggered enough that upstream and downstream share the flow. Dutch colonial officers marveled at the 'amazingly high standard of rice cultivation' a century before anyone could explain it.
In the 1970s, Indonesia's Green Revolution 'massive guidance' campaign ordered Balinese farmers to give up their own irrigation schedules and grow the new high-yield rice continuously. Yields rose briefly; then, as the Tabanan regency public works office reported in 1985, brown planthoppers, rodents and tungro virus exploded, and uncoordinated planting produced water shortages the report called chaotic. The farmers' verdict, recounted to researchers decades later: why have we abandoned a legacy that was already good? — and they returned to planting together on the temple calendar.
换别人会怎么做
Modernize: distribute the agronomy ministry's continuous-cropping calendar to every farmer — which destroyed the fallow-pest-water balance the temple calendar had been quietly computing for centuries.
他们看到了什么
The temples were not folklore; they were a distributed optimization algorithm. The Green Revolution replaced a mechanism it could not see, and the watershed paid in pests and conflict until farmers restored it.
那一手
The temples turn out to have been doing distributed optimization. Each subak balances two opposing forces — pest control needs fallow patches synchronized large enough to starve insects and rats; water sharing needs not too many fields fallow at once — by meeting and negotiating with neighboring subaks up and downstream, and imitating the schedules of the most successful. Lansing and Kremer's simulation, seeded with every subak acting purely independently, converged through exactly such imitation to cropping patterns close to the observed temple schedules and to the harvest-maximizing balance; a survey of 149 farmers found upstream farmers fear pests while downstream farmers fear water shortage — precisely the gradient the temple calendar arbitrates.
为什么管用
The core tradeoff is physical: pests die only when fallow patches are large and synchronized, but water runs short when too many fields rest at once — solving it requires a watershed-scale pattern that no single farm can compute. Temple meetings link each subak to its upstream and downstream neighbors, and ritual makes the resulting calendar binding in a way no posted notice is; imitation of successful neighbors converges near the harvest-maximizing equilibrium without any central controller. Because the calendar is sacred, compliance is self-enforcing — nobody has to police it.
值了多少
Continuous planting bred pest explosions and water chaos (Tabanan report, 1985); farmers returned to temple-coordinated calendars
什么时候会失灵
It optimizes for a slow-moving equilibrium: when pests, climate or water demand shift faster than ritual adapts, the calendar lags. Critics have contested how 'optimal' the temples are — the optimality result rests on model assumptions, and farmers also follow commercial motives. And where membership erodes through land sales and off-farm jobs, the coordination layer thins no matter how legitimate the ritual remains.
后来呢
The subak landscape entered UNESCO's World Heritage list in 2012; Lansing's work became a classic of complex-systems and common-pool resource research alongside Ostrom's, and the episode is taught as the canonical case of coordination hidden inside ritual.
资料来源
- [1]The Functional Role of Balinese Water Temples: A Response to Critics (Human Ecology)Human Ecology (Springer), 2012slansing.org
- [2]Adaptive self-organization of Bali's ancient rice terracesPNAS (Lansing et al.), 2017pnas.org