Effects Of Chemical Fertilizers Combined With Soil Amendments On Saline Soil Improvement And Rice Yield

Saline-alkali land is a low-yield land because of the harm of saline-alkali and with poor soil conditions.It has the characteristics of high p H,high salt content and excessive soluble salt.Based on the background,it is very difficult for plants growing on saline-alkali soil to absorb nutrients and grow,which ultimately leads to low productivity of saline-alkali soil.At present,the land resources in China have been severely weakened,and the gradual rise of various infrastructure and ecological construction occupy a large amount of land and arable land,even reaching the"red line"of arable land.As a reserve land resource,saline-alkali land can effectively relieve the pressure on cultivated land after development and utilization.Therefore,studying the improvement technology of saline-alkali land can provide a solid foundation for realizing the effective utilization of saline-alkali land,improving grain productivity and ensuring food security.The experiment studied the effects of different soil amendment on Saline-alkali land soil physical and chemical properties,crop yield and quality by applying soil conditioners,calcium and magnesium fertilizers,amino acid fertilizers and organic fertilizers.The results of the study showed that amino acid fertilizers had the greatest impact on soil p H.Compared with the unimproved soil,p H value was reduced by0.70 and 0.80 with the application of 2 levels of amino acid fertilizers,the drop rates were 7.75%and 8.86%,respectively.The four soil conditioners can all lower the soil p H,and the trend was:amino acid fertilizer>organic fertilizer>soil conditioner=calcium magnesium fertilizer.Calcium and magnesium fertilizers had the greatest impact on soil salinity.After applying two levels of calcium and magnesium fertilizers,the soil salt content was reduced from 0.510%to 0.171%and 0.159%,with a decrease of 66.47%and 68.82%,respectively.All four soil amendments can reduce soil salinity,and the trend was calcium and magnesium fertilizers>organic fertilizers>amino acid fertilizers>soil conditioners.The four soil conditioners can increase the yield of rice,among which the high dosage treatment group(soil conditioner 4500kg/hm~2,calcium and magnesium fertilizer 1250kg/hm~2,amino acid fertilizer 2500L/hm~2,organic fertilizer 15000kg/hm~2)was higher than the low dosage treatment group(soil conditioner 2250kg/hm~2,calcium and magnesium fertilizer625kg/hm~2,amino acid fertilizer 1250L/hm~2,organic fertilizer 7500kg/hm~2)yield increased by 25.35%.The trend of influence on the yield of the four soil amendments was organic fertilizer>soil conditioner>amino acid fertilizer>calcium and magnesium fertilizer.Using Multiple Linear Regression analysis(MLRA)to establish a multiple linear regression equation of soil p H,the results showed that the trend of the influence of soil physical and chemical properties on soil p H was:available potassium(P<0.05)>salinity(P<0.05)>water-soluble potassium(P>0.05)>Water-soluble calcium(P>0.0.5)>Organic matter(P>0.05).Among them,salinity,water-soluble calcium and water-soluble potassium had a positive effect on soil p H,while organic matter and available potassium had a negative effect on soil p H.The estimated standard error was 0.04.Then establish a multiple linear regression equation between rice yield and soil physical and chemical factors.The results showed that the effect of each factor on rice yield was:water-soluble sulfate(P>0.05)>salt(P<0.05)>water-soluble calcium(P<0.05)>water-soluble magnesium(P>0.05)>water-soluble carbonic acid Hydrogen radical(P>0.05)>fast-acting potassium(P>0.05).Among them,available potassium,water-soluble calcium,and water-soluble sulfate had a positive effect on rice yield,while salt,water-soluble magnesium,and water-soluble bicarbonate had a negative effect on rice yield.The estimated standard error was 171kg/hm~2.After applying soil conditioner 4500kg/hm~2,calcium and magnesium fertilizer 1250kg/hm~2,amino acid fertilizer 2500L/hm~2,and organic fertilizer 15000kg/hm~2,the rice yield was 7171kg/hm~2.Compared with the original soil,the contents of alkali hydrolyzable nitrogen,available phosphorus and available potassium had increased by 31.12mg/kg,3.39mg/kg,22.58mg/kg respectively,while the alkalinity had decreased from 35%to7.77%.It shows that applying soil conditioners,calcium-magnesium fertilizers,amino acid fertilizers,and organic fertilizers can effectively regulate the saline-alkali soil environment and improve crop quality indicators.Applying amendments to improve saline-alkali soil is a reasonable and effective plan.