dc.description.abstract | In Taiwan, most irrigation water distribution depends on manual work,
meanwhile, the water of irrigation and the lost from the conveyance can
not be accurately calculated. This situation turns worse as the climate
change leads to uneven rainfall. If the water usage in which accounts for
70% of water usage, can be allocated more precisely, it would improve
water resource allocation effectivity. This study applies system dynamic
model to establish irrigation water management model, combining rainfall
and irrigated water, the model simulated two scenarios by decaeasing 30%,
and 50% planned irrigation water in the wet year 2013. The result shows
that field capacity of the end of the tested area, no. 5 round regin, will lower
than wilting point, under 50% decreased water of irrigation plan. It appears
that the original irrigation plan still have some extra reduction in the future.
To probe the feasibility of automatic irrigation in the field, the model,
built by this study, was used to estimate the demand of irrigation to the test
area in the first crop, 2015. After sending to the cloud data center, the
calculated flow will be acquired at the timing of every 2 hours by the
automatic gate in the field, and the gate achieves flow adjustment in 1 hour.
During testing period, because of the out flow always greater than 0.5 times
of the inflow, the threshold set by this study for saving water, the gate can
only operate under the target flow 0.46cms. However, the automatic
operation result shows about 7.9 tons/day can be saved from the dynamic
adjustment, and comparing to the target flow, only 526.5 tons water lost
during the operating hour, with the error ratio being 1.79%. The
contribution of this study provide the effectivity in water saving with the
combination of accurate irrigation model and automatic adjustment gate. | en_US |