拓跋鲜卑阴山却霜与阴山南北的粮食作物与牧草保护

Tuoba Xianbei’s Antifrosting for Protecting the Grain Crops and Pasture in the North and South of Yinshan Mountains

《宋书》《资治通鉴》记拓跋鲜卑有阴山(今大青山)却霜之俗。《宋书》史官对阴山却霜之俗的解释,是基于对阴山地理环境以及农业防霜经验的了解,具有可信性。西汉时期已存在可称为“拉霜”的防霜经验,南北朝时期已存在熏烟防霜法。《宋书》史官对阴山却霜的理解,正与熏烟防霜法同理,且“却霜”一词为后世所沿用。拓跋鲜卑所占驻的匈奴故地,阴山横亘,常年霜雪不消,成为一个冷空气源,足以影响周围区域的气候。北魏世祖、高宗、显祖率大众停驻阴山的时间主要在农历六、七、八月,这一时期是阴山南北地区粮食作物与牧草的生育期,防霜是必要的。停驻阴山期间大众生活所必然产生的烟气,可减少阴山作为冷空气源的作用,减少霜的发生,保证粮食作物与牧草稳定高产。

According to Book of Song Dynasty and Hisory as a Mirror,Tuoba of Xianbei had a custom of antifrosting in Yinshan Mountains(now Daqing Mountains).By comprehending the geographical environment of Yinshan Mountains and the experience in agricultural antifrosting,the historiographer of Book of Song explained the custom of antifrosting in Yinshan Mountains authoritatively.There was a kind of antifrosting called‘lashuang’before Tuoba occupied the former place of the Huns,and then another by the name of hypatmism came into being,similar to the principle of the so-called antifrosting in Yinshan Mountains.The place occupied by the Tuoba of Xianbei,where Yinshan Mountain stretched across the country,with perennial frost and snow,became a source of cold air.The emperors like Shizu,Gaozhong and Xianzu stayed in Yinshan mountains mainly during the period from June to August while the grain crops and pasture growed from seedling to maturity and antifrosting was necessary.The so-called antifrosting in Yinshan Mountains worked like antifrosting by hypatmism.The smoke generated from life activities could weaken the force of cold air by reducing the occurrence of frost and even hail to ensure a stable and high yield.