Using Hydrus-2d Model for Simulating Soil Water Dynamics in Drip-Irrigated Citrus
Upotreba modela hydrus-2d za simulaciju dinamike zemljišne vlage kod citrusa sa navodnjavanjem kap po kap
Author
Panigrahi, Pravukalyan
Sharma, Rama Kant
Keywords
citrussoil water dynamics
drip irrigation
Hydrus-2D
dinamika zemljišne vlage
navodnjavanje kap po kap
Hydrus- 2D
Metadata
Show full item recordAbstract
The demand of water for irrigation is gradually increasing due to
escalating competition for fresh water by urban, industrial, and agricultural users. To
sustain or increase agricultural productivity, there is a need to adopt highly efficient
irrigation technologies such as drip irrigation in crop production. Studies related to water
dynamics in crop root zone is the pre-requisite for efficient and economic design of any
irrigation system. In the present study, the water dynamics under drip irrigation was
evaluated taking citrus as a test crop in sandy loam soil. The soil water content observed
in effective root zone (0–60 cm) of the crop showed that water availability was higher in
top 15 cm soil, whereas at 45–60 cm soil depth the water content remained unchanged.
Drip emitter placement in tree basin had a good influence on water distribution in root
zone. The soil water content was simulated using HYDRUS-2D model to compare the
observed data of water distribution in the soil in root zone of the crop. The calibrated
model predicted all the parameters close to observed values with root mean square
(RMSE) values ranging from 0.013 to 0.015. However, lower RMSE values were
observed at deeper soil layers. At fruit maturity stage, water present at 45-60 cm soil
depth was predicted to be 12.5% higher in comparison to measured values. Overall,
HYDRUS-2D model has proved it’s ability to predict soil water dynamics with higher
accuracy in the present crop and soil condition. Potrebe za vodom za navodnjavanje se postepeno povećavaju zbog
povećanih potreba za svežom vodom u urbanim, industrijskim i poljoprivrednim
područjima. Za održavanje i povećanje poljoprivredne proizvodnje potrebno je
prilagođavanje visoko efikasnih tehnologija navodnjavanja kao što je navodnjavanje kap
po kap. Proučavanje dinamike zemljišne vlage u zoni korenovog sistema je preduslov za
efikasno i ekonomično projektovanje sistema za navodnjavanje. U ovom istraživanju
analizirana je dinamika vlage kod navodnjavanja kap po kap plantaže citrusa kao
oglednog zasada na peskovito-ilovastom zemljištu. Sadržaj zemljišne vode praćen je u
efektivnoj zoni korena (0–60 cm) i uočeno je da je dostupnost vode bila veća u gornjih
15 cm zemljišta, dok je na dubini od 45–60 cm sadržaj vode ostao nepromenjen. Položaj
kapalice u osnovi stabla uticao je na raspodelu vode u zoni korena. Sadržaj zemljišne
vlage bio je simuliran modelom HYDRUS-2D radi poređenja izmerenih podataka
raspodele vode u zoni korena biljaka. Kalibrisani model je predvideo sve parametre blizu
izmerenih vrednosti, sa srednjim kvadratnim odstupanjem od 0.013 do 0.015. Ipak,
manje vrednosti odstupanja su uočene u dubljim zemljišnim slojevima. Pri stanju pune
zrelosti voća, procenjeni sadržaj vode prisutne na dubini od 45-60 cm bio je 12.5% veći
u poređenju sa izmerenim vrednostima. Ukupno, model HYDRUS-2D je pokazao svoju
sposobnost da predvidi dinamiku zemljišne vlage sa visokom tačnošću kod ovig zasada i
i u ovim zemljišnim uslovima.