| This study focused on the area where the farmlands had been irrigated with sewage from Fuhe River in Qingyuan County in Hebei province for many years. At first, a questionnaire survey was conducted to clear the conditions for sewage irrigation and Farmer’s awareness of relationship between sewage irrigation and human health along Fu River. Then, an investigation of Cd, Pb in soil-crops of the sewage irrigation farmland along Fuhe River was carried out to assess Cd, Pb contamination in soils and edible crops. After that, a Field experiment was carried out to screen crops cultivars with low Cd, Pb accumulation. The major findings were summarized as follows:(1) An Investigation of local farmers concern on soil pollution along the Fu RiverTo clear the conditions for sewage irrigation and farmer’s awareness of relationship between sewage irrigation and human health along Fuhe River, the nine villages along Fu River were investigated by the questionnaires. Local farmers irrigate the farmlands with groundwater, mixture of groundwater and sewage, and sewage, accounting for 66.7%, 8.33% and 25.0% respectively. Most of the farmers is not clear effects of sewage irrigation on soil environmental quality, crop production and human health, accounting for 72.2%, 83.3% and 79.2%; About 16.7%, 11.1% and 10.7% of farmers could recognize the impact of sewage irrigation on soil environmental quality, crop production and human health. Local farmers should pay more attention to the consequences of sewage irrigation, and the relationship between sewage irrigation and soil contamination and human health.(2) Investigation of Cd, Pb concentrations in soil-crops of the sewage irrigation farmlands along Fu RiverAccording to the investigation results, the sewage irrigation farmlands were divided into four regions: control area, previoussewage irrigation area, presentsewage irrigated and smelting area along Fuhe River. The concentrations and distribution of Cd, Pb in soil-crops of the sewage irrigation farmland along Fuhe River were explored. The results showed that the concentrations of Cd in 2.14%, 82.86% and 81.82% of soil samples exceeded the limitation of the Environment Quality Evaluation Standaras for Farmland of Edible Agricultural Products and Pb concentrations in 11.42%, 3.45% and 36.36% of soil samples exceeded the limitation of that standard in the previous sewage irrigated area, presentsewage irrigated area and smelting area, respectively. The concentrations of Cd, Pb in grains of maize were less than the Maximum levels of contaminants in foods. The wheat grains were contaminated by Cd and Pb, and Pb pollution levels were higher than that of Cd. The contamination of Cd and Pb in the soil from smelting area was worse than other regions. The Cd and Pb concentrations in 18.18% and 63.64% of soil samples exceeded the limitation of standard. In addition, Cd, Pb concentrations in soil of the previous sewage irrigation area reached the warning level, and reached the light contamination level in the present sewage irrigation area and smelting area. Smelting activity and irrigation with wastewater increased the concentrations of Cd, Pb in soil-crops, and increased human health risk.(3) Screen summer maize cultivars with low accumulation of Cd, PbA Field experiment was carried out to study the differences of cadmium and lead accumulation and translocation in 9 cultivars of summer maize in north of Huanghuaihai region, which aimed to screen summer maize cultivars with low accumulation ability of Cd, Pb in the irrigation farmland of the Fu River. There was a significant difference(P<0.05) in yields, heavy metals(Cd, Pb) concentrations in grains and straws among 9 cultivars. Xianyu-335 had the highest yield at 12 389 kg/hm2, 32% to 93% higher than those of other cultivars; Moreover, Xianyu-335 had the minimum concentrations of Cd in grains at 0.004 4 mg/kg, 7% to 45% lower than those of other cultivars; Luoyu-803 had the minimum concentrations of Pb in grains at 0.027 3 mg/kg, 37% to 50% lower than those of other cultivars, and the concentrations of Cd, Pb of grains for all cultivars were less than the Maximum levels of contaminants in foods. Based on the most important index Comprehensive assessment, cultivars of Xianyu-335 was selected with high yields and low accumulation of Cd, Pb in summer maize, and should be suitable and extended in farmland contaminated lightly with Cd, Pb in north of Huanghuaihai region.(4)Screen winter wheat cultivars with low accumulation of Cd, PbA Field experiment was carried out to study the differences of cadmium and lead accumulation and translocation in 10 cultivars of winter wheat in the north of Huanghuaihai region, which aimed to screen winter wheat cultivars with low accumulation ability of Cd, Pb in the irrigation farmland of the Fu River. There was a significant difference(P<0.05) in yields, heavy metals(Cd, Pb) concentrations in grains and straws among 10 varieties. Shixin-633 had the highest yield at 8 400 kg/hm2, 7% to 23% higher than those of other cultivars; Shixin-828 and Jimai-22 had the higher yield, 1% to 15% higher than those of other cultivars; Moreover, Liangxing-66 and Jiai-22 had the lower concentrations of Cd in grains, 11% to 48% and 2% to 42% lower than those of other varieties; Luyuan-50 and Jimai-22 had the lower concentrations of Pb in grains, 14% to 49% and 14% to 40% lower than those of other varieties, and the concentrations of Cd, Pb of grains for all cultivars were less than the Maximum levels of contaminants in foods. Based on the most important index Comprehensive assessment, cultivars of Jimai-22 was selected with high yields and low accumulation of Cd, Pb in winter wheat, and should be suitable and extended in farmland contaminated lightly with Cd, Pb in north of Huanghuaihai region. |
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