Spatial distribution and influencing factors of rice irrigation water demand based on GIS

Abstract

The spatiotemporal distribution of irrigation water demand is the main basis for scientifically formulating irrigation quotas and management strategies for different regions. Using daily meteorological data from 15 meteorological stations in the southeastern coastal area of Zhejiang Province over the past 30 years, the Penman Monteith method recommended by FAO was used to calculate the irrigation water demand for rice throughout its entire growth period. Using the spatial analysis function of GIS, obtain the spatial distribution map of rice irrigation water demand through inverse distance weight interpolation method. The results show that there is a significant spatial difference in the irrigation water demand for rice in the southeastern coastal areas of Zhejiang Province, with an average annual value ranging from 202.9 to 586.4mm/season. The annual average shows a decreasing distribution pattern from east to west. By analyzing the spatial distribution pattern of rice irrigation water demand in the southeastern coastal areas of Zhejiang, targeted irrigation management strategies are proposed, which can provide scientific basis for irrigation water management in Wenzhou, Taizhou, and Ningbo.