亚洲人成网站18禁止中文字幕,国产毛片视频在线看,韩国18禁无码免费网站,国产一级无码视频,偷拍精品视频一区二区三区,国产亚洲成年网址在线观看,国产一区av在线

 
AGRICULTURE
 

 

???? A number of tribes in ancient China had a fairly well-developed agriculture. As early as the Qin Dynasty (200 B.C.) the Luoyues in south China cleared jungle land and had developed cultivation and crop irrigation. In what is now Xinjiang, grain, mulberry trees, hemp, grapes and other crops were already being grown by minority peoples 2,000 years ago. Crops such as sorghum, maize, cotton, sesame, grape, watermelon, cucumbers and carrots were introduced into the central areas from the "Western Regions." During the Tang-Song period 1,000 years ago the Wuman and Baiman groups in Yunnan developed water conservancy and irrigation projects on a large scale at Changshan, Dali and Dianchi. The crops of 10,000 "qing" (roughly 67,000 hectares) of land on the Dali Plain were guaranteed at the time by the "Cross Ditch" and "Jinlang River" irrigation works, part of a network with eighteen other water courses covering the whole plain. The Tubo people, in what is now Tibet, had in the Tang Dynasty attained a relatively high level of development in growing wheat, highland barley, buckwheat and kidney beans and in tilling land and irrigating crops. The Fuyus and Yilous of the Han Dynasty had learned to grow cereal grains.

????By enlarging their acreage from 400,000 shang (hectares) to 2,900,000 shang during the Qing Dynasty, the Manchu people inhabiting the Fengtian area of Liaoning in the Northeast became self-sufficient in food grain.

 

 

    1. <ul id="556nl"><kbd id="556nl"><form id="556nl"></form></kbd></ul>
      <thead id="556nl"></thead>

      1. <em id="556nl"><tt id="556nl"></tt></em>
        <ul id="556nl"><kbd id="556nl"><form id="556nl"></form></kbd></ul>

        <ul id="556nl"><small id="556nl"></small></ul>
        1. <thead id="556nl"></thead>

          亚洲人成网站18禁止中文字幕,国产毛片视频在线看,韩国18禁无码免费网站,国产一级无码视频,偷拍精品视频一区二区三区,国产亚洲成年网址在线观看,国产一区av在线 人妻无码久久影视 日韩久久久久久久久久久久 精品国产香蕉伊思人在线 无码国产手机在线a√片无灬 91在线视频无码