Period , qin and han dynisties ( 221 b . c . - 220 ) period , three kingdoms and jin dynasty ( 220 - 420 ) period , sui and tang dynasties ( 581 - 907 ) period , song and yuan dynasties ( 960 - 1368 ) period , and ming and qing dynasties ( 1368 - 1911 ) period ; the agricultural exploitation progressions were made step by step , and were going upward from the basin to the hill and mountain areas with comprehensive , vertical and cash crops system emphasized in different stages 第六章宋元时期陕南农业的全面发展宋元时期,作为农业开发的基础一人口出现了较快的增长,为农业发展提供了丰富的劳动力。同时,由于陕南地处战略形胜之地,宋王朝在此进行了大规模的屯田。增修水利工程,倡行稻麦两熟制,发展梯田农业,重视农业的多种经营成为宋元时期陕南农业开发的主体。
By the ranking model by similarity to ideal point based on m and n , the criterion of cultivated land can ’ t be used as plant cash crops and the criterion of cultivated land should priority used as plant cash crops and the criterion of cultivated land can ’ t be used as construction land and the criterion of cultivated land should priority used as construction land were confirmed . finally , the evaluation of cultivated land grade , realistic class , and potential class were all demonstrated and the result of cultivated land grade , realistic class , and potential class were all verified in a case study in changsha county changsha city , hunan province . by calculated cultivated land coefficient m and n and confirmed c _ m and c _ n of the ranking model by similarity to ideal point , the result 0 . 5032 < c _ m 0 . 9931 was confirmed as the criterion of cultivated land should priority used as plant 最后以湖南省长沙县作为典型研究区域,实证了耕地等、现实级和潜在级的评价,并分析了其评价结果的可靠性;通过计算耕地经粮系数和建粮系数,及逼近于“理想点”的排序模型中的c _ m和c _ n确定了长沙县0 . 5032 < c _ m 0 . 9931为耕地应优先用作菜地等经济作物用途和0 . 0126 c _ m < 0 . 5037为耕地不应用作菜地等经济作物用途的判别标准;确定了长沙县0 . 5035 < c _ n 0 . 9937为耕地应优先用作建设用地用途和0 . 0139 c _ n < 0 . 5035为耕地不应用作建设用地用途的判别标准;最后阐明了c _ m 、 c _ n在种植业结构调整、耕地保护和土地管理中的应用价值。
Connotation of cultivated land coefficient m was defined as the degree of cultivated land quality when used as plant cash crops was superior to cultivated land quality when used as plant food crops . connotation of cultivated land coefficient n was defined as the degree of cultivated land quality when used as construction land was superior to cultivated land quality when used as plant food crops . calculated method of cultivated land coefficient m and n were confirmed 确定它们的内涵,经粮系数是“同一耕地用作种植蔬菜等经济作物用途时和用作种植粮食作物用途时,该耕地适于蔬菜等经济作物的质量优越于该耕地适于粮食作物的质量的程度” ;建粮系数是“同一耕地用作建设用地用途时和用作粮食作物用途时,该耕地适于建设用地的质量优越于该耕地适于粮食作物的质量的程度” 。
Compared to the area of cereal , cash crop and vegetable in shunyi district with that of china , the proportion of cereal and cash crop area was at lower level , whereas the proportion of vegetable area is far more than that of whole china , indicating the characteristic of dominance situation of horticulture landuse in suburb of big city life breijing 从种植业的粮、经、蔬三元结构与全国比较来看,顺义区粮食作物和经济作物比重偏小,而蔬菜作物的比例却远远高于全国。这样的土地利用格局反映了大城市郊区都市型农业用地以粮为辅,蔬菜、园艺为主的特色。
In the demonstration section of the paper , aiming at the main plantation crops and variety in shanxi and each region in shanxi , some research has been done , including determining and analyzing scale advantage , efficiency advantage and aggregated advantage of the main grain crops ( including wheat , corn , millet , soja , jowar and tubers ) and main cash crops ( including oil - bearing crops , cotton , fiber crops , beetroots , tobacco , medicinal materials , vegetables and melon , fruit ) in shanxi , determining and analyzing scale advantage , efficiency advantage , benefit advantage and aggregated advantage of the main plantation variety ( including wheat , corn , millet , soja , jowar , cotton , beetroots , rapeseed , flue - cured tobacco and apple ) in shanxi , determining and analyzing the advantage in each region in shanxi . the research shows that some crops and variety in shanxi own advantage , they are millet , jowar , fruit ( apple ) , beetroots and medicinal materials . meanwhile , the main crops regions owning advantage and combination of advantage crops in each region in shanxi have been gained 在文章的实证研究部分,本文以山西省及各地区的主要种植业作物和品种为研究对象,做了以下几方面的研究:测定和分析了山西省主要的粮食作物(小麦、玉米、谷子、大豆、高粱和薯类)和主要经济作物(油料、棉花、麻类、甜菜、烟叶、药材、蔬菜、瓜类和水果)的规模优势、效率优势和综合优势并与全国主产区进行了比较;对山西省主要的种植业品种(小麦、玉米、谷子、大豆、高梁、棉花、油菜籽、甜菜、烤烟和苹果)的规模优势、效率优势、效益优势和综合优势进行了测定和分析;测定和分析了山西省主要种植业作物在各地区的竞争优势,研究表明山西省具有比较优势的作物主要有谷子、高梁、水果(苹果) 、甜菜和药材,同时得出山西省主要作物优势产区和各地区优势作物组合。