气候变化对陇东冬小麦生态影响特征研究

Study on the influence of climate change to winter wheat ecological characteristic in the east of Gansu

对黄土高原比较有典型代表性的残塬“董志塬”的变暖及冬小麦生态响应特征进行研究,发现“董志塬”近35 a来年平均增温线性趋势达0.0505℃,增温表现出平均气温、最高气温、最低气温同时上升,且冬春季增温速度最快,秋季次之,夏季增温最平缓;增温对冬小麦的生态影响主要体现在全生育期(线性趋势0.91 d/a)、越冬期(线性趋势0.85 d/a)显著缩短,春季发育期普遍提前(返青期以0.57 d/a的线性趋势提前,拔节期以0.42 d/a的线性趋势提前,成熟期以0.48 d/a的线性趋势提前),而春季各发育期间间隔日数并未出现缩短的趋势。认为气候变暖对当地农业生产有利有弊,气候变暖,尤其冬春气温显著升高将导致越冬期土壤水分损耗增大,春旱加剧,不利于春季农业生产;另一方面冬小麦全生育期缩短,成熟期提前,能有效提高复种指数和土地利用率。

This paper analyzed the warming of Dongzhi Yuan, an incomplete Yuan as a typical representative of loess plateau, and the ecological response characteristics of winter wheat to such a change. The results showed that Dongzhi Yuan＇s mean warming linear trend up to 0. 0507℃ during the past 35 years, with all the indexes increasing, such as the mean temperature, the maximum temperature and the minimum temperature. The most remarkable temperature increasing occurred in winter and spring, then in autumn, while that in summer was the least. The warming＇s influence to the ecological characteristics of winter wheat was mainly showed by the shortening of the whole growth period and the advancing of most of the growth stages, while the interval has not presented the trend of shortening during spring. It is concluded that the warming of Dongzhi Yuan can cause certain adverse effects, such as the increase of winter wheat freezing injury probability in spring and the fading of existing variety adaptability, the apt condition for diseases and insect pests to live through the winter, the increase of soil moisture loss in winter etc, while it also has some positive effects like the shortening of the whole growth period, the earlier mature and the increase of land use efficiency.