As a major agricultural practice in mainland China,crop rotation that experiences multiple harvests during a certain period and in a same land plays a vital role in increasing its land productivity and securing national food production.To devise better adaption and increase national food production under a fasting warming world,it is necessary to add the understandings regarding statues of current crop rotation systems in China,impacts of climate change on the systems,and responses of the systems to various warming trajectories.This paper reviews latest works related to crop rotations,with particular focuses on the responses of crop rotations to historical and future climate change.Most studies investigate the interactions between crop rotation and climate change based on three methods:crop modeling,statistical analysis,and field experiment,each method exhibits specific defects and merits.Authors summarize current understandings about the influence of climate change on crop rotation from four aspects:crop growth,crop spatial distribution,cost and benefits,and production risks.Authors explore adaptive practices in rotations and in the end recommend research directions for the future.This review increases the understandings about the impact of climate change on crop rotations and provides useful information for developing wise rotation strategy in coping with climate change.Previous studies illustrated that climate change has already affected and would continue to influence crop rotations,but discrepancies existed among studies because differences in spatial and temporal scales,methodology,and research subjective.Majority of the studies showed that warmer climate and increasing heat resource made it possible for some rotation systems to move north,which had substantially altered crop patterns and shifted planting area for a few major crops.Higher temperature physiologically speeds up crop growth,accelerating crop phenology and leading to lower yield.But this acceleration,on the other hand,creates great opportunities for switching of crop varieties and replacement of crop type.The increases in total heat resources during the growing-season lead to spatial and temporal variations of climatic disasters,requiring reconsideration of conventional copping strategies.For example,although reduction of cold disaster has been observed in many crop areas,on the contrary,the occurrence of the cold disaster actually has increased recently in many crop areas due to shifting of planting boundaries and over-adaptations.Together with increased heat stresses under warming climate,these new disaster patterns posed additional threats for alleviation of agricultural climate disasters,jeopardizing the productivity,stability,and sustainability of many rotation systems.Theoretically,yield loss caused by climate change could be offset by appropriate adjustment of crop patterns,adoption of new crop varieties,such as cultivars with longer growth period,and optimization of management practices.However,because of complexity of the systems,we failed to make a concrete and consistent conclusion regarding the interactions between climate change and crop rotation based on reviewed researches.Future works are recommended to emphasize the integration of multi methods to increase understandings related to mechanism,comprehension,and systematization of crop rotation systems,and to pursue in-depth investigation with wider connection between climate change and crop rotation and decreasing research uncertainty.%轮作耕作方式在提高土地利用率和单位面积作物产量方面发挥了不可替代的作用,加强气候变化对轮作系统影响的理解,揭示其对气候变化的响应规律,是促进轮作生产体系有效应对和适应气候变化的关键.本文梳理了气候变化对轮作系统影响的研究成果和不足,总结当前常用研究手段(作物模型、统计和试验方法)的优缺点,从作物生长发育、种植布局、种植效益、种植风险4个方面阐述了气候变化对轮作系统产生的影响,并对现有的适应性措施以及今后研究重点进行分析,以期为全面深入评估气候变化对轮作系统的影响,以及未来轮作系统的研究和发展提供一定参考和借鉴.已有研究结果表明,气候变化已经影响,而且还将继续影响轮作系统.尽管因研究的时空尺度、方法及轮作模式的不同,研究结果还存在一定差异,但大部分研究表明,在宏观层面上,气候变暖,热量资源增加,使得研究区轮作系统种植界限发生明显北移,导致不同轮作系统的作物布局及种植面积发生改变.微观角度上,气温升高加快了轮作系统内部作物生育进程,导致作物产量下降,也为系统内品种更换提供了可能.热量资源的变化,还导致轮作系统内部所遭遇的气象灾害规律发生变化,传统意义上的低温灾害事件将减少,但是种植界限变动的敏感区内新的低温灾害事件以及极端高温事件则有增加的趋势,从而增加了轮作系统高产、稳产及可持续发展的风险.生产中,通过改变作物布局,选用生育期更长的品种,以及优化管理措施等,可以在一定程度上减缓气候变化对轮作系统的不利影响.但是,由于气候变化和轮作系统的复杂性和多样性,目前研究还存在一定的不足,今后还需结合多种研究手段,开展气候变化对轮作系统影响的机理性、综合性以及系统性研究,提高研究的深度、广度、精度和准确度,以促进和保障其可持续发展.
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