基于GIS技术的中国农田钾素养分收支平衡研究

基于农田养分收支平衡模型、农业经济统计数据,结合GIS 技术,研究了2000年我国农田K素的平衡特征,并利用GIS技术对研究结果进行了空间表达与分析.主要结论有:①我国农田 K 素投入总量为1.068 × 107 t,农田 K 素总支出为1.458 × 107 t,农田 K 素处于亏缺状态,亏缺量为3.90 × 106 t,平均单位耕地 K 素亏缺 40 kg/hm2;②在县域层面上,农田 K 素处于亏缺的县域单元数占全部县域单元数的 77.39%,我国绝大多数的县域单元农田 K 素处于亏缺状态;③我国农田 K 素输入中化肥 K 素投入4.77 × 106 t,有机肥 K 素投入总量为4.98 × 106 t;④在全国层面上,由人畜禽粪尿提供的 K 占全部有机 K 肥总投入的比例为48.98%,由秸秆提供的 K占全部有机肥 K 素投入总量的比例为51.02%;⑤全国农田 K 素支出总量中 K 素生物产出总量为1.335 ×107 t,占农田 K 素总支出的比重为 91.56%.

Balance of Farmland Potassium Nutrient Input/Output in China Based on GIS

Based on agricultural economy statistical data, the model of farmland nutrient balance of input/output and GIS, the balance characteristic of farmland potassium nutrient and its spatial distribution in China in 2000 was studied. The conclusions were as follows: 1) the total input of potassium for farmland was 1.068 ×107 t in China, but the output was 1.458 ×107 t, with a deficit of 3.90 ×106 t (40 kg/hm2), 2) at county level, 77.39% of the counties in China showed a deficit supply of potassium, 3) in the total input of potassium for farmland, the chemical potassium fertilizer amounts to 4.77 ×106 t and the organic potassium fertilizer to 4.98×106 t, 4) at national scale, the potassium provided by the excrement and urine of human and animals and the crop straw occupy 48.98% and 51.02% of the total potassium supply, respectively, 5) the biological output of potassium from national farmland amounts to 1.335×107 t, was 91.56% of the total expenditure.