Fig. 3

Soil nutrient content in different sample plots: soil (a) total nitrogen; (b) total phosphorus; (c) total potassium; (d) available nitrogen; (e) available phosphorus; (f) available potassium; (g) organic matter.

Soil nutrient content in different sample plots: soil (a) total nitrogen; (b) total phosphorus; (c) total potassium; (d) available nitrogen; (e) available phosphorus; (f) available potassium; (g) organic matter.