Qimin Yaoshu (Important Methods for the People's Welfare)

Qimin Yaoshu (Important Methods for the People's Welfare), a monograph of agriculture-related topics in ancient China, was written by Northern Wei Dynasty agriculturalist Jia Sixie, between the late years of the Northern Wei Dynasty (386-534) and the early years of the Eastern Wei Dynasty (534-550). Qimin Yaoshu is the earliest agricultural text that is completely preserved in China, and it is crowned as "the encyclopedia of ancient Chinese agriculture."

Qimin Yaoshu comprises 10 scrolls, 92 chapters, with a total of over 70,000 Chinese characters, plus over 40,000 characters of annotations. The book emphasizes the importance of agriculture; it comprehensively summarizes the experience of peasants living in the middle and lower reaches of the Yellow River before the 6th century, including agricultural production experience, processing of agricultural products and methods for their storage, the way to open up wasteland and so on. The book tells how season, climate and soil affect the growth of crops, and emphasizes that different varieties of crop should grow in the right season, on right land and with right farming methods. In addition, the book sheds light on the comprehen- sive analysis of agricultural production, science and technolo- gies as well as how more economic benefits can be created. It advocates improving technologies and production tools, and provides knowlege about fighting a drought, recovering land fertility, and seed selection and breeding.

This book not only tells about the advanced level and leading position of China's agriculture at the time but also has a far-reaching influence on the development of agriculture and agricultural science and technology. As one of the earliest agricultural monographs in global agriculture history, Qimin Yaoshu spread to other parts of the world including Japan and Europe, becoming a classic in the study of species variation.

《齊民要術》

中國古代綜合性農學專著《齊民要術》，由北魏農學家賈思勰撰寫，約成書于北魏末年（533—544），是中國現存最早的一部完整的農書，被譽為“中國古代農業百科全書”。

《齊民要術》全書共10卷、92篇，正文7萬多字，注釋4萬多字。這一著作強調農業的重要性，全面總結了6世紀以前黃河中下游地區勞動人民長期積累的農業生產經驗、農產品加工和貯藏以及治荒的方法等，詳細介紹了季節、氣候、土壤與農作物的關系，強調農業生產要因時因地，因作物品種而采取不同辦法。此外，書中重視對農業生產、科學技術和經濟效益的綜合分析，提倡改革生產技術和生產工具，總結了抗旱、恢復提高土壤肥力、選種育種等生產技術知識。

《齊民要術》不僅反映了古代中國領先于世的農業發展水平，而且對后世農業發展和農業科學進步產生了深遠影響。作為世界農學史上最早的專著之一，《齊民要術》先后傳至日本、歐洲等地，成為海內外研究古物種變化的經典。