青海玛沁县东部表层土壤养分地球化学评价

张浩, 牛尧, 张海旭, 沙惠兰

Geochemical evaluation of surface soil nutrients in eastern Maqin County, Qinghai Province, China

ZHANG Hao, NIU Yao, ZHANG Hai-Xu, SHA Hui-Lan

图3 土壤中氮、磷、钾等养分指标地球化学等级分布

Fig.3 Geochemical grade of nutrient elements such as nitrogen, phosphorus, and potassium in soil