*2.3. Analysis of Scientific Knowledge*

Local knowledge was examined by scientific knowledge of the following hydro- meteorological events and systems.


$$SPI = \frac{\underline{x}\_i - \overline{x}}{\sigma}$$

where, *xi* is a specific period (e.g., monthly, annual) rainfall during the year *i*, *x*, and σ are the long term mean and standard deviation in the specific period. Floods and drought were identified using the *SPI* scale, as shown in Table 1. Positive and negative *SPI* values indicates that precipitation is above and below average, respectively [27]. We calculated *SPI* values based on monthly precipitation using the 18 years precipitation of TRMM.


**Table 1.** The floods and drought classification on standardized precipitation index (*SPI*) indices.

3. Farming system. We consulted previous studies to obtain data on crop patterns, fertilization, and water management.
