气候变化对松嫩平原水稻灌溉需水量的影响

Effect of climate change on rice irrigation water requirement in Songnen Plain,Northeast China

以水稻为研究对象,选取松嫩平原20个国家气象台站和国家气象中心提供的格点气象数据,采用作物系数法和Mc Cloud模型及P-M模型估算水稻需水量,应用水量平衡模型估算水稻灌溉需水量,分析水稻生育期内需水量变化规律.结果表明:历史时期和气候变化情景下,松嫩平原水稻全生育期和生育中期(Lmid时段)灌溉需水量等值线沿西南-东北方向递减,同一灌溉需水量等值线北移.历史时期和气候变化情景下水稻全生育期灌溉需水量随年代呈波动增加趋势,其中前者以44.2 mm·10 a-1速度增加,后者以19.9 mm·10 a-1速度增加.历史时期和气候变化情景下Lmid时段水稻灌溉需水量随年代均呈波动增加趋势,其中前者显著增加,后者增加不显著.气候变化情景对水稻需水量的贡献率为波动上升,与1970s相比,2000s气候变化对水稻需水量的贡献率为23.6%,增加14.8×108m3灌溉水量;2040s气候变化对水稻需水量的贡献率为34.4%,增加21.2×108m3灌溉水量.

Abstract： Based on meteorological data from China national weather stations and climate scenario grid data through regional climate model provided by National Climate Center, rice water require- ment was calculated by using McCloud model and Penman-Monteith model combined with crop coefficient approach. Then the rice irrigation water requirement was estimated by water balance model, and the changes of rice water requirement were analyzed. The results indicated that either in historical period or in climate scenario, rice irrigation water requirement contour lines during the whole growth period and Lmid period decreased along southwest to northeast, and the same irrigation water requirement contour line moved north with decade alternation. Rice irrigation water requirement during the whole growth period increased fluctuantly with decade alternation at 44.2 mm ·10 a^-1 in historical period and 19.9 mm ·10 a^-1 in climate scenario. The increase in rice irrigation water requirement during the Lmid period with decade alternation was significant in historical period, but not significant in climate scenario. Contribution rate of climate change to rice irrigation water requirement would be fluctuantly increased with decade alternation in climate scenario. Compared with 1970s, contribution rates of climate change to rice irrigation water requirement were 23.6% in 2000s and 34.4% in 2040s, which increased 14.8×10^8m^3 irrigation water in 2000s and would in- crease 21.2×10^8m^3 irrigation water in 2040s.