哈尼梯田水稻灌溉需水量变化特征分析OA

The Hani Terraced constitute the primary rice-cultivating region in the dry-hot river valleys of Southwest China.Scientific irrigation practices for rice cultivation in this area hold profound significance for safeguarding regional grain production capacity and preserving the millennia-old agricultural civilization associated with the Hani Terraced.Nevertheless,there remains a paucity of research on the variation characteristics of irrigation water requirement during the rice growth period in the Hani Terraced.This paper takes the core area of Hani terraced rice cultivation as the research object.Based on the daily meteorological data from Yuanyang Station for 55 years(1970-2024),the climate tendency rate method was adopted to analyze the temporal variation characteristics of meteorological elements,reference crop evapotranspiration(ET0),irrigation water demand and irrigation water requirement,and irrigation watear requirement index in the study area,and to propose the irrigation quota for terraced rice under the"rice-fish-duck"integrated farming system.The results show that the effective accumulated temperature and effective rainfall during the growth period of rice growth period exhibited an increasing and a decreasing trend,respectively,with climate tendency rates of 19.3 ℃·10a-1 and-14.5 mm·10a-1.From the interannual variation of ET0,it was found that ET0 during the rice growth period showed an increasing trend,with the most significant upward trend occurring from 2010 to 2024.From the monthly variation of ET0,the high-value period of ET0 was concentrated in the rice growth period from April to September,accounting for 60％of the annual total.The stage with the highest net irrigation water requirement during the rice growth period in different typical years was the tillering stage,with an average value of 100.6 m3·667m-2,accounting for 36％of the total net irrigation water requirement for the entire growth period;the second was the heading and flowering stage,with an average value of 57.6 m3·667m-2.The stage with the lowest irrigation water requirement was the yellow ripening stage,with an average value of 17.1 m3·667m-2.The irrigation water requirement index for the rice growth period showed a gradually increasing trend over the years,with an increase of 0.02 per decade.Considering the"rice-fish-duck"integrated farming system,the average water consumption of rice was 5％～20％higher than that of conventional rice cultivation,and the multi-year average net irrigation quota was 280.5 m3·667m-2.The irrigation quota for terraced rice under the"rice-fish-duck"integrated farming system proposed in this paper can provide a reference for scientific irrigation of rice in the Hani Terraces.