土壤农艺调控措施对苹果和果园土壤镉污染的影响

Effects of Several Agronomy Regulations on Soil Cadmium Pollution in the Apple Orchard

以10a生红富士苹果树为试材,通过土施不同剂量的氯化镉和改良剂,研究了增施有机肥、磷钾肥以及土施生石灰等土壤农艺调控措施对苹果园镉污染的影响。结果表明:各处理的土壤有效镉含量、苹果叶片和果实镉含量均极显著低于对照。在本试验所设9个处理中,不同镉剂量处理下,以200g/kg有机肥+30g/kg生石灰+0.5g/kg磷钾肥处理和100g/kg有机肥+30g/kg生石灰+1g/kg磷钾肥处理的镉含量为低,使低、中、高3个镉剂量区土壤有效镉含量分别比对照减少36.6%,31.5%,22.9%;土壤有效镉含量比例分别比对照降低24.8%,21.4%,21.4%;叶片镉含量分别比对照减少41.6%,34.7%,17.0%;果实镉含量分别比对照减少53.9%,31.0%,28.6%。根据拟合公式推算出:当土壤镉含量低于2.95mg/kg时,200g/kg有机肥+30g/kg生石灰+0.5g/kg磷钾肥处理的果实镉含量较低;高于2.95mg/kg时,100g/kg有机肥+30g/kg生石灰+1g/kg磷钾肥处理的果实镉含量较低;两处理土壤镉调控极限值分别为7.84mg/kg和11.59mg/kg。在实验浓度范围内,土壤有效镉含量以及对苹果叶片、果实镉含量的直接通径系数和极差分析值均以生石灰为最高,有机肥次之,磷钾肥最低。生石灰对土壤有效镉含量以及对苹果叶片、果实镉含量的调控作用最强,有机肥次之,磷钾肥最小。

10-year-old Fuji apple trees were used as materials to study the effect of several agronomy regulations on soil cadmium pollution in apple.The results showed that：All treatments of the cadmium content in soil,leaf and fruit of apple were positive significant below the comparison.All treatments,with the different soil cadmium treated,in which the cadmium content is lower in treat of 200 g/kg organic fertilizer＋30 g/kg quicklime ＋0.5 g/kg potassium phosphate and 100 g/kg organic fertilizer＋30 g/kg quicklime＋1 g/kg potassium phosphate.The treatments reduced the cadmium content by 36.6%,31.5%,22.9% in effective cadmium content and 24.8%,21.4%,21.4% in effective cadmium proportion and 41.6%,34.7%,17.0% in leaf and 53.9%,31.0%,28.6% in fruit.Calculated in formula,the soil cadmium content below 3.57 mg/kg,the fruit cadmium content in treat of 200 g/kg organic fertilizer＋30 g/kg quicklime＋0.5 g/kg potassium phosphate is lower;exceed 3.57 mg/kg,the fruit cadmium content in treat of 100 g/kg organic fertilizer＋30 g/kg quicklime＋1 g/kg potassium phosphate;the maximum value of the treatments is 7.64 mg/kg and 11.97 mg/kg。Within the concentration for the experiment,the path analysis and R value on cadmium content in soil,leaf and fruit indicated that,the value of quicklime is the highest,the organic fertilizer is lower,the potassium phosphate is the lowest.The effects of several agronomy regulations on soil cadmium pollution,in which the quicklime is the best,the organic fertilizer is lower,the potassium phosphate is the lowest.