“历史时期黄河流域气候变化与农耕文明演变”笔谈

About the Relationship between Climate Changing and the Evolution of Agricultural Civilization in the Yellow River Basin in Historical Period

黄河流域是中华文明的主要发祥地,所孕育的农耕文明深远地影响了中国古代经济、政治和文化,而作为农业生产主要资源的气候,无疑又是基础要素之一。这就使生长在黄河岸边的我们对历史时期黄河流域气候变化与农耕文明演变高度关注,乃至充满感情。这既是历史观照,是地理审视,是现实关怀,恐怕更深层的还是个人生命体验。2012年拙作《北宋开封气象编年史》出版后,据中国科学院自然科学史研究所研究员韩毅先生告知,有关院士很重视,并指出如果在时间上贯穿就更有价值了。而今,我们做的就是这个初步工作,希冀学界更多地关注。本次笔谈论文以古代史下半段为研究时段。张仲胤《天时与人谋:魏晋气候变迁与黄河流域农业生产》提出,气候变迁作为影响农业生产的重要因素,其影响机制是复杂的。魏晋时期的寒冷干旱气候等不仅严重冲击了黄河流域的农业生产,还促进了农田水利设施兴建与农业技术提升;由于后者,魏晋时期的粮食产量突破“冷抑暖扬”规律而反超两汉。李杰文《唐代黄河流域气候变化下的甜瓜种植》认为唐前期黄河流域气候温暖湿润,中后期渐趋寒冷干旱,气候变迁导致甜瓜种植及消费情况发生变化,甜瓜在唐代经历了从珍稀到常见、再从常见到珍稀的过程,文士则赋予其文化意蕴。惠冬《气候、社会与10-13世纪黄河中下游稻作区的演变》指出,作为对气候敏感度较高的传统农业中的重要作物的水稻,对研究历史时期气候变迁与农耕演进具有显著的指标意义,而随着温暖-寒冷周期的变化等,10-13世纪的黄河中下游地区的稻作区由扩张趋向收缩,稻作区的演变是天人共塑的一种历史农业景观。孙朋朋《元代黄河流域气候剧变与植棉业推广》发现,黄河流域气候在元朝前期至中后期发生了由温暖适宜骤然入冷的变化,导致喜温经济作物的生产效益显著降低,经济作物种植结构亦产生相应调整,棉花作为新兴经济作物遂在黄河流域得到广泛种植。宋先杰《气候变迁、社会选择与明清黄河中下游柳树的兴盛》选择具有耐寒、易成活、生长快等特点的柳树,考察在小冰期影响下的明清时期黄河中下游地区植被的适应、生存,柳树得以成为黄河中下游的主要植被景观。

The Yellow River basin is the main birthplace of Chinese civilization,and the agricultural civilization which conceived and grew up here has a far-reaching impact on China’s ancient economy,politics and culture.Climate,as the main resource in agricultural production,is undoubtedly one of the basic elements of agricultural civilization.As people growing up on the banks of the Yellow River,we should pay close attention to the climate change in the Yellow River basin and its relationship with the evolution of agricultural civilization.The study of the relationship between climate change and the evolution of agricultural civilization in the ancient Yellow River basin is not only a geographical survey,but also a requirement of the realistic development.Climate change is an important factor affecting agricultural production,but its mechanism is very complicated.The cold and dry climate and natural disasters in the Wei and Jin Dynasties on the one hand severely impacted the agricultural production,and on the other hand promoted the construction of water conservancy facilities and the improvement of agricultural technology.As a result,the grain output in the Wei and Jin Dynasties not only did not decrease due to the decrease of temperature and precipitation,but also exceeded that in the Han Dynasty.During the early Tang Dynasty,the climate in the Yellow River Basin was warm and humid,but it gradually transitioned to colder and drier conditions in the mid to late Tang period.These climate changes influenced the cultivation and consumption of melons.When the climate conditions were favorable for melon growth,the court established specialized institutions to explore and develop cultivation techniques,including breeding early ripening varieties.Conversely,when the climate was unfavorable,the rarity of melons increased,and literati imbued them with cultural significance.Throughout the Tang Dynasty,melons underwent a transition from being rare to common and then back to rare again.From the 10th to the 13th century,as the climate in the middle and lower reaches of the Yellow River changed from a warm period to a cold period,the rice cultivation area shifted from expansion to contraction.The confrontation between the Song,Liao and Jin regimes and the political and military policies of each regime also promoted or restricted the cultivation of rice.In other words,the evolution of rice farming areas in the middle and lower reaches of the Yellow River from the 10th to the 13th centuries is a historical agricultural landscape shaped by nature and man.The climate of the Yellow River Basin in the early Yuan Dynasty was warm and suitable.But it entered a cold period in the middle and late Yuan Dynasty,and the sudden drop in temperature significantly reduced the production efficiency of thermophilic economic crops.In the Yuan Dynasty,the planting structure of economic crops in the Yellow River Basin also changed,and cotton was widely planted in the Yellow River Basin.The promotion of cotton planting in the Yellow River Basin has significantly changed the planting structure of original economic crops.Under the influence of Little Ice Age,the climate of Ming and Qing Dynasties was cold.Climate cooling affected the survival of vegetation in the middle and lower reaches of the Yellow River.Because of its cold-resistant,easy to survive,fast growth and other characteristics,willow is an important material in agriculture and forestry planting,urban beautification,river defense construction and so on,and is deeply valued by the society.Willow became the main vegetation landscape in the middle and lower reaches of the Yellow River.