华北地区冬小麦灌溉制度及其环境效应研究进展

Review on research of irrigation regime and its environmental effect in winter wheat field of North China Plain

充分利用有限的灌溉水资源确保冬小麦安全生产是华北地区冬小麦稳产高产面临的严峻挑战,解决这一问题的关键在于如何基于环境效应科学地进行灌溉管理。综述了国内外有关冬小麦的灌溉管理制度,即充分灌溉与非充分灌溉管理制度以及冬小麦关键灌溉期的环境效应,在此基础上提出了华北地区冬小麦科学灌溉拟重点关注的研究任务:(1)冬小麦生长发育需水时间与需水量的控制机制研究;(2)冬小麦干旱发生发展过程与致灾临界气象条件研究;(3)气候变化背景下极端干旱事件的冬小麦脆弱性诊断与适应性管理,以为华北地区冬小麦安全生产措施制定提供依据。

The North China Plain known as ＂China granary＂ is the main winter wheat producing areas. However, it has been frequently and seriously affected by drought because of monsoon climate, especially winter drought and spring drought have been frequent and serious during recent decades. Making full use of the limited irrigation water resources to guarantee the safety of winter wheat production is a serious challenge for ensuring stable and high yield of winter wheat in the North China Plain. The key to solving this problem is how to make a scientific irrigation management based on the environmental effects. Although many studies have been done on drought and water-saving irrigation systems of winter wheat, there were less comprehensive commentary recently and still a lot of insufficiencies on interactive combinations of irrigation time, irrigation frequency and the environment effects, which have been based on overwintering water and the first springing water, especially for the adverse effects of current climate change and water shortage. This paper reviews the latest researches at home and abroad on the irrigation management systems （sufficient irrigation and deficit irrigation） and the environmental effects of irrigation in the key irrigation periods of winter wheat in the North China Plain. The responses of various developmental stages and physiological processes of winter wheat to water deficit are different. In particular developmental stages, the water deficit is not entirely negative effects, and it might have some adaptive effects on moderating water deficit to a certain extent. Deficit irrigation is through the artificial stage regulation to form state water budget at different developmental stages of winter wheat. Based on the theory of vulnerability and adaptability to drought, winter wheat will adjust its distribution pattern of assimilation to various organs. This process includes the impacts on many aspects：such as the development stages, weather conditions, the soil＇s physical, chemical and biological properties, and winter wheat yield. Eventually winter wheat will achieve the change of passive responses on water deficit. The purpose is to improve the conversion efficiency at each stages of irrigation water-soil water-plant water-photosynthesis-biomass-yield. The key to ensure stable and high yield of winter wheat in the North China Plain with deficit irrigation is to determine the critical water demand period under different environmental conditions. Overwintering water （usually is replaced by sowing water or in advance of reviving water）, the first spring water and their irrigation interactive combination will make different environment effects, and affect the time and frequency of the other irrigation waters, various stages of growth and development of winter wheat, especially in reviving and the late growth. Finally the future research tasks of winter wheat scientific irrigation in the North China Plain are proposed, including （1） Control mechanisms on temporal and amount dynamics of water demand for the growth and development of winter wheat; （2） Processes of occurrence and development of winter wheat drought and its critical meteorological conditions for causing disasters; （3） Vulnerability diagnosis and adaptive management of winter wheat responding to extreme drought events under climate change. These researches would provide reference for the development of measures to safety production of winter wheat in the North China Plain.