溶磷细菌对复垦土壤养分、酶活性及磷解析的影响

为了探索溶磷细菌在复垦土壤上对磷素的作用效果,采用室内摇瓶培养的方法,研究了磷细菌及其组合对磷酸三钙的溶解能力,确定了最佳组合磷细菌。拉恩式菌(W2)+荧光假单胞菌1(W3)+荧光假单胞菌2(W4)培养液的有效磷含量最高,为609.1mg/L,故最佳磷细菌组合为W2+W3+W4。将筛选出的最佳组合磷细菌在采煤塌陷地复垦土壤上进行玉米大田试验,研究其对土壤养分、酶活性、磷解析特性及玉米产量的影响。结果表明:磷细菌可以增加土壤养分含量和改善土壤酶活性;磷细菌处理土壤有效磷和速效钾含量,以及磷酸酶、蔗糖酶和脲酶活性分别比基质对照处理增加了2.80,25.43,7.41,4.21,7.15mg/kg;与空白处理相比,磷细菌处理土壤最大吸磷量和吸附常数降低幅度最大,分别显著减少114mg/kg和0.021(p0.05);磷细菌处理土壤平均解吸率为14.7%,显著高于其他处理;磷细菌处理玉米产量最高,为8 036kg/hm~2,显著高于其他处理。因此在复垦土壤上施用磷细菌,可以改善土壤磷素解析特性,有利于土壤快速培肥,对作物增产也有积极作用。

Effect of Phosphobacterias on Nutrient, Enzyme Activities and Phosphorus Adsorption-Desorption Characteristics in a Reclaimed Soil

The aim of this paper was to study the effect of phosphobacterias on phosphorus in a reclaimed soil.The tricalcium phosphate-solubilizing ability of individual phosphobacteria and their combinations was tested using laboratory shake-flask culture.The culture broth of Rahnella sp (W2) + Fluorescent pseudomonas1 (W3)+ Fluorescent pseudomonas2 (W4) produced the highest available P content,609.1 mg/L.Therefore,W2+W3+W4 was selected as the optimal combination of phosphobacterias.The effects of the optimal combination of phosphobacterias on soil nutrients,enzyme activities,P desorption properties,and maize yield were investigated by carrying out a field experiment in a reclaimed soil in a coal-mining subsidence area.The results showed that phosphobacterias increased soil nutrient contents and improved soil enzyme activities.Soil available P and K contents,as well as phosphatase,invertase,and urease activities,were increased by 2.8,25.43,7.41,4.21 and 7.15 mg/kg,respectively,by phosphobacterias compared to the medium control.The greatest reduction in the maximum P adsorption capacity (114 mg/kg) and adsorption constant (0.021) of soil was found with phosphobacterias compared to the blank control (p＜0.05).The mean P desorption rate of soil with phosphobacterias was 14.7,significantly higher than those in other treatments.The highest maize yield was also obtained with phosphobacterias,which was 8 036 kg/hm2 and significantly different from those in other treatments.In conclusion,the application of phosphobacterias could improve soil P desorption properties,facilitate rapid improvement of soil fertility,and contribute to crop yield in reclaimed soils.