Technology Research On Improvement Of Saline Land In Western Jilin Province By Compost Sludge

Using the seedling culture test and pot experiment,and alfalfa as test plants,the compost sludge was mixed at the ratio of 0,10%,20%,30%,40%,and 60%of the saline soil mass ratio(dry weight ratio),to study the effects of different compost additions on the soil properties of saline soil in western Jilin Province.The physicochemical properties,nutrient content,soil enzyme activity changes of saline soil and correlation studies between some indicators were analyzed.The results showed that the physical and chemical properties of saline soil after fertilization treatment were improved in the seedling culture experiment and pot experiment.The bulk density of the soil in the control group decreased from 1.66 g/cm~3 and 1.58 g/cm~3 to 1.04 g/cm~3 and 1.02g/cm~3,respectively.p H of soil significantly reduced by 29.32%,35.60%,close to neutral and suitable for plant growth.The cation exchange capacity(CEC)increased by 32.54%~154.05%and 9.03%~103.01%,respectively,and the soil water retention and fertility capacity were improved.The value of soil EC was slightly increased.Compared with the control group,the alkalization sodium content in the fertilized soil reduced by 0.23 to 3.92coml/kg and 0.18 to 3.34 cmol/kg,respectively.The corresponding degree of alkalization had also reduced to a greater extent.In the pot experiment,the degree of soil alkalization reduced by 74.06%at the 40%fertilization rate;in the seedling culture experiment,it reduced by 90.40%at 60%the fertilization rate,and the effect was very obvious.The content of organic matter in the soil after fertilization treatment increased exponentially,and the contents of total nitrogen,available nitrogen,total phosphorus,available phosphorus and available potassium increased significantly,while the total potassium content changed little,and soil nutrient content greatly improved.The catalase activity and urease activity in the soil increased with the amount of compost sludge,which was significantly different from that of the control group.This indicated that the compost sludge promoted the life activity of soil microorganisms to a certain extent,thereby increasing the activity of soil enzyme.The correlation analysis showed that the soil organic matter was significantly negatively correlated with soil bulk density and p H,and positively correlated with soil CEC,catalase activity,and urease activity,and soil EC was distinctly positive correlated with catalase activity and urease activity,respectively.Improvement with compost sludge,plant height and the accumulated biomass of the alfalfa in the saline soil both increased,and reached the maximum in 40%fertilization soil.The utilization rate of nitrogen and phosphorus reached the maximum at the 40%fertilization rate.Considering the effects of compost sludge on the physical and chemical properties,nutrient content,soil enzyme activities of saline soil,and the effects on alfalfa growth,it was recommended to apply 40%of compost sludge to saline soil,which could not only effectively improve the characteristics of saline soil,but also make full use of the fertilizer efficiency of composted sludge.