【摘要】 土壤有效水分对玉米的生长发育及产量形成至关重要,研究不同生育阶段的土壤有效水分贮存量与玉米产量形成因素的关系对玉米生产防灾减灾具有重要的理论和实际意义。本文利用黑龙江省玉米主产区1994-2017年的农业气象观测数据,采用Mann-Kendall趋势检验、相关分析等方法,分析玉米基于土壤相对湿度指数(Rsm)的干旱频次时空分布规律,探索有效水分贮存量对玉米不同发育阶段产量形成各因素的影响。结果表明:1994-2017年研究区玉米各发育阶段平均有效水分贮存量在14-16mm之间,共发生干旱162次,其中轻旱116次,中旱36次,重旱9次,特旱1次,发生干旱的频次总体表现逐年降低,2012年为干旱频次下降的突变点,下降趋势明显。玉米主产区播种-出苗期天数平均为15.5天,与0-40厘米土层的有效水分贮存量呈显著负相关。玉米的气象产量受拔节至乳熟期的浅中层土壤有效水分影响较大;玉米的果穗长和茎杆重与不同发育期的各层次的土壤有效水分贮存量相关性不大;果穗粗与玉米苗期中深层土壤、玉米旺盛营养生长期及生殖生长期所有层次的土壤有效水分呈正相关;株籽粒重与三叶-抽雄期的30-50厘米土壤有效水分贮存量相关性较大;百粒重与出苗-三叶期的20-50厘米土层的土壤有效水分贮存量呈显著负相关;各生长发育阶段土壤中水分过多,秃尖现象越重。更多还原

【Abstract】 The effective moisture of soil is important to the growth and the yield formation of the corn. It is of great theoretical and practical significance to study the relationship between the storage of effective moisture of the soil and the formation factors of the corn yield in different fertility stages. Based on the data of agricultural meteorology of 1994-2017 in Heilongjiang Province and using the methods of Mann-Kendall trend test and correlation analysis, it analyzed the classification of drought grades based on relative moisture of the soil. It also studied the effect of storage of effective moisture on corn yield formation in different development stages. The main conclusions are as follows: The average storage of effective moisture in different development stages of corn was between 14-16 mm from 1994 to 2017. There were 162 droughts, of which mild drought were 116 and moderate drought were 36 and severe drought were 9 and the special severe drought were 1. The frequency of drought in the study area was decreasing year by year. The downward trend was obvious and the year of 2012 was the mutation point of the frequency of drought decreased. The average number of days of sowing to seedling emergence was 15.5 days in the main producing areas of corn, which has negative correlation with the storage of effective moisture in 0-40 cm soil layer. The soil available water storage in the shallow middle layer from jointing to milk ripening stage had a great influence on the meteorological yield of corn. The ear length and stem weight of corn had little correlation with soil available water storage at different stages of development. There was a positive correlation between ear diameter and storage of effective moisture in middle and deep soil of seedling and all layers of vigorous vegetative growth period and reproductive growth stage. There was a significant correlation between the grain weight of the plant and the storage of effective moisture of 30-50 cm in the trefoil stage to tasseling stage. Hundred-grain weight had a significant negative correlation with storage of effective moisture in the 20-50 cm soil layer of the seedling to trefoil stage. The more water was in the soil, the more serious corn baldness.更多还原