Data Reconstruction of Heihe River Basin Cultivated Land Area prior to the Ming Dynasty
明代以前黑河流域耕地面积重建

As an important agricultural grain base in northwest China and one of the earliest regions with large-scale oasis agricultural development,the Heihe River basin has undergone much change since ancient times. Due to the limitations and omissions of historical records on agricultural production,analysis of changes in cultivated land area before the Ming Dynasty is lacking. Selecting the Han,Tang and Yuan Dynasties with relatively rich historical documents as research periods,two different reconstruction methods based on per person cultivated land area and grain yield were used to reconstruct the quantity of cultivated land area across the Heihe River basin prior to the Ming Dynasty. Results show that the area of cultivated land reached maximal value during the Western Han Dynasty (from 16.30×104 hm2 to 19.49×104 hm2). Following this dynasty,cultivated land area declined during the Eastern Han,Tang and Yuan Dynasties,with areas from 9.57×104 hm2 to 11.80×104 hm2,from 3.59×104 hm2 to 3.93×104 hm2 and 3.19×104 hm2 in each period. Comparing the two reconstruction methods showed that the former one is largely in line with the latter one,and confirms the reliability of reconstruction results and changes in cultivated land.