气候变化对临沂冬小麦主要生育期的影响及适播期研究

为了研究气候变化对临沂市冬小麦生产的影响,确定合理播期和适宜的田间管理措施。利用2001—2021年临沂市气象资料和农业农村部门苗情调查数据,同时参考1962—2000年临沂市历史天气数据,采用线性趋势性预测对小麦生育期温度、积温以及主要生育期日期和持续时间进行变化规律分析。结果表明:临沂市冬小麦适播期和各生育期均对气候变化发生了不同的响应,适播期为10月8—19日,最佳播期为10月11—14日;分蘖期出现反复降温频率变高,促进了小麦冬前抗寒锻炼,利于形成壮苗;冬前积温增多和越冬期延迟,间接推迟了适播期,为上一季玉米晚收创造了条件;返青大幅提前和返青后积温显著增加,大幅缩短了小麦停止生长和越冬时间,增加了冬小麦实际生长时间,有利于冬小麦苗情转化;拔节期大幅提前,使小麦更容易遭受晚霜冻(冷)害和倒春寒;4月和5月温度下降为小麦抽穗、扬花、灌浆提供了更好的气候条件,特别是5月温度下降既减少了干热风的发生机率又利于小麦后期灌浆。确定了临沂市冬小麦适播期,为小麦全生育期田间管理和高产栽培提供了依据。

Effects of Climate Change on Main Growth Stages of Winter Wheat in Linyi and Determination of Suitable Sowing Time

To study the impact of climate change on winter wheat production in Linyi City and determine the suitable sowing time and appropriate field management measures, based on the meteorological data of Linyi City from 2001 to 2021 and the seedling survey data of agricultural and rural departments, as well as the historical weather data of Linyi City from 1962 to 2000, we adopted the linear trend prediction to analyze the change law of temperature and accumulated temperature during the winter wheat growth period and the date and duration of main growth stages. The results showed that the suitable sowing time and each growth stage of winter wheat in Linyi City had different responses to climate change. The suitable sowing time was from October 8 to 19, and the best sowing time was from October 11 to 14. The frequency of repeated cooling in tillering stage increased, which enhanced the cold resistance of wheat before winter and was conducive to the formation of strong seedlings; the increase of accumulated temperature before winter and the delay of overwintering period indirectly delayed the suitable sowing time, which could provide better conditions for the late harvest of maize of the previous cropping. The early returning green and significant increase of accumulated temperature after returning green greatly shortened the growth suspension and overwintering time of wheat, increased its actual growth time, and was conducive to the transformation of winter wheat seedling; the early jointing stage could make wheat be more vulnerable to late frost (cold) and late spring cold. The temperature drop in April and May provided better climatic condition for wheat heading, flowering and grain filling, especially, the temperature drop in May, which not only reduced the probability of dry hot wind, but was also conducive to wheat grain filling in the later stage. This study determined the suitable sowing time of winter wheat in Linyi City, and provided a basis for field management and high-yield cultivation of wheat in the whole growth period.