Concentrations of heavy metals (Pb, Zn, Cd, Cu) were determined in soils and vegetables (chrysanthemum, spinach and four cultivars of Chinese cabbage from the area adjacent to a Pb/Zn mine in Shaoxing, Zhejiang province, China, and compared with the Chinese National Standards for Soil Environmental Quality. The accumulation of heavy metals in cabbage cv. Siyuegreen was investigated at different distances from the center of the mine. The vegetable plantation soils were polluted with Pb, Cd, Cu and Zn, especially by Pb and Cd. The levels of Pb and Cd were 20 and 30 times higher than the permitted standards, indicating that this Pb/Zn mining area is unsuitable for agricultural use. Chinese cabbage, chrysanthemum and spinach had different enrichment coefficients. The enrichment coefficient of Cd from soil to roots of chrysanthemum was >80% and from roots to leaves of cabbage cv. Shanghaigreen was >120%. These vegetables were polluted by heavy metals and could not be regarded as safe for human consumption. Environmental accumulation of heavy metals in the vegetable plantation soils was proportional to heavy metal accumulation in vegetables and both were inversely proportional to the distance from the lead/zinc mine.

The risk of P leaching from topsoil based on the change‐point estimated via a split‐line model between Olsen P and leachable P extracted by 0.01 M CaCl2 has been reported. However, little information is available for the assessment of P leaching from soil profiles. In this study, samples were collected at three depth profiles (0–20 cm, topsoil; 20–40 cm, subsoil; 40–60 cm, third‐layer soil) at each of 74 sites under agriculture and forest in an agroforestry area. A cascade extraction method was proposed to determine the leachable P in the subsoil, extracted by the topsoil extraction solution; a similar extracted process was followed in the third‐layer soil, and in the topsoil, it was still extracted by 0.01 M CaCl2. A positive linear correlation was found between the subsoil leachable P extracted by the topsoil extraction solution and the accumulated P obtained from the subsoil leached by topsoil leachates, and so on. Therefore, the cascade extraction method for determining leachable P from topsoils and underlying soils could be valuable for predicting the potential of P leaching from soil profiles. Approximately 81, 73, and 73% of the agricultural sampling sites were at or above the change‐points for the soil depths of 0 to 20, 20 to 40, and 40 to 60 cm (30.4, 32.9, and 18.2 mg kg−1 respectively); these values were higher than those for the forest site, implying a high risk of P leaching from agricultural soil profiles in the study area. Core Ideas A cascade extraction method for evaluating P leaching from soil profiles was proposed. The correlation of soil leachable P and accumulated P in soil leachates was confirmed. The risk of P leaching from soil profiles in an agroforestry area was calculated.

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