Preliminary Study On The Improvement Effect Of Adsorbent Nanomaterials On Soda Alkali Soil

To filter the optimization the program of improving soda alkaline soil by adsorbent nanomaterials,the experiments were designed that four types of nanomaterials?NH₄,Ca,PSA and H?were applied at eight concentrations?0?CK?,2.5,5,10,20,30,40 and 50 g/kg?to find suitable dose and the appropriate ratio between PSA and H of nanomaterial on the improvement of soda alkaline soil.Lab simulation tests and pot experiment were arranged to discover the effect of he chemical properties of soda alkaline soil and the agronomic characters of maize at seedling stage by the measurement of soil pH,electrical conductivity,base ions and organic matter,plant height,stem diameter,leaf area and biomass of maize at seedling stage.The main results were as follows:?1?All treatments had no significant effect on the contents of Mg²⁺,Cl^-and organic matter of the tested soil?P>0.05?.?2?The results of the screening test of applied dose of nanomaterials showed that the four nanomaterials had the highest effect on the improvement of chemical properties of soda alkaline soil when the nanomaterials were all applied at 50 g/kg.Compared with CK,the pH decreased by 3.97%,5.58%,3.69%and 7.09%,respectively,the EC decreased by 32.2%,39.01%,32.3%and 34.1%,respectively,the content of Na⁺decreased by 28.7%,43.5%,29.7%and 34.4%,respectively,the content of K⁺decreased by 18.6%,43.5%,11.3%and 13.7%,whereas just PSA significantly decreased the content of CO₃^2-by 15.5%?P<0.05?and only H significantly reduced the content of HCO₃^-by 16.4%?P<0.05?,when the dosage of the four nanomaterials was 50 g/kg.?3?The results of pot experiments showed that the improvement effect of PSA and H of nanomaterial on chemical properties of soda alkaline soil were better than that of Ca and NH₄.Compared with CK,the contents of EC and Na⁺in soda alkaline soil were significantly decreased by nanomaterial?P<0.05?,the degree of influence was PSA>H>Ca=NH₄.Compared to CK,PSA increased the contents of Ca²⁺by32.5%and 30.4%,respectively,while decreased the contents of CO₃^2-by 13.5%and11.5%,respectively;meanwhile,the contents of Ca²⁺significantly decreased by H,Ca and NH₄?P<0.05?,but only H of nanomaterial decreased HCO₃^-concentration by9.31%and 8.81%,respectively,when soybean and maize were planted.?4?The co-application of PSA and H showed that the effect of T1?50PSA:0H?,T2?30PSA:20H?,T3?25PSA:25H?,T4?20PSA:30H?and T5?0PSA:50H?on cations were greater than anions.Compared with CK,all the treatments could reduce the contents of pH,EC,Na⁺and K⁺contents?P<0.05?,whereas T1 and T2 treatment decreased greatly,but the effect on pH had no difference.T1 and T2 increased the contents of Ca²⁺by 40.15%and 17.98%,respectively,whereas T5 decreased the contents of Ca²⁺by 23.1%.?5?The pot experiment of combined application of PSA and H showed that seeds of maize did not emerge at T5 and CK treatment.T1,T2,T3 and T4 could improve the stem diameter,plant height,leaf area and biomass of maize at seedling stage.Among the four treatments,the mean values of plant height,leaf area,aboveground and underground biomass under T1 treatment were the highest as14.261 cm,445.876 mm²,0.725 g and 1.04 g.Therefore,T1 treatment was the best way to improve the agronomic characters of maize seedlings.