温带人工草地上经济施用钾肥研究

ECONOMIC BENEFITS OF K APPLICATION RATE ON IMPROVED LEGUME PASTURE IN THE MID-ALTITUDE REGIONS OF YUNNAN PROVINCE

在以豆科为主的温带人工改良草地上,随着钾肥施用量的增加则使得牧草干物质产量增加。当纯钾施用量达40公斤/公顷时,不仅牧草干物质产量较高,而且比较经济,每投入纯钾1公斤,可获得干物质15～25公斤,牧草产量可达2500公斤干物质/公顷。如果钾肥施用量超过每公顷40公斤纯钾时,牧草总产虽有增加,但单位肥料量所获得的牧草干物质则开始下降。

A trail on the economic benefits of K application rate for legume based improved pasture was carried out in the mid-altitude regions of Yunnan. The preliminary results showed the herbage yield was increased as increase of K fertilizer under the experimental conditions. The herbage yieid was 2500kgDM/ha at the rate of 4Okg/ha K, one kg of Potassium produced 25 kg DM. When the application rate of K is more than 40 kg/ha, although the total yield of pasture increased, the ratio, of input and output began to decrease.