Figure 3From: Determination of production regions for pollution-free Chinese medicinal materials by geographic information system: Achyranthes bidentata (Niu Qi) in Tianjin as an exampleStandardization results of evaluation factors. (a) mean July temperature. (b) mean January temperature. (c) relative humidity. (d) active accumulated temperature. (e) sunshine duration. (f) annual precipitation. (g) mean annual temperature. (h) the lowest temperature in January. (i) the highest temperature in July.Back to article page