保水剂对不同质地土壤保肥性影响的研究

摘要

Using different dosage of super absorbent polymer (SAP)and same dosage of potassium sulfate,a pot ex-periment was carried out to investigate the effects of different dosage of SAP on nutrient retaining property in three soils with different textures .The results show that:(1 )SAP could reduce potassium ion concentration in the soil eluent, which was negatively correlated to dosage of SAP .This meant that SAP improved the potassium retaining capacity of the soils with different textures .(2)The effect degree of SAP to nutrient retaining capacity was different among the three kinds of soil,which could be ordered as:sand >loam >clay .(3)SAP increased significantly the residue of potassi-um sulfate in the soils .In sand,loam and clay,the application of 0 .25% SAP could save potassium by 25 .5 1%, 4 .70%and 2 .06%,respectively,compared with the control .Therefore,SAP was remarkably effective in retaining soil fertility,and it could reduce the leaching loss of soluble nutrients to a certain extent .%试验在三种不同质地的土壤中加入不同用量的保水剂和相同用量硫酸钾进行，利用花盆试验研究保水剂不同用量对不同质地土壤保持养分能力的影响。结果表明，（1）保水剂能降低土壤淋洗液中钾离子浓度，且钾离子浓度与保水剂用量呈负相关，表明保水剂对三种质地土壤保持钾素的能力都有所提高；（2）保水剂对三种质地土壤养分保持能力的影响大小程度依次为砂土、壤土、粘土；（3）保水剂使土壤中硫酸钾残留量都较对照显著提高，砂土、壤土和粘土中分别加入0．25％保水剂较对照分别节钾25．51％、4．70％和2．06％。试验表明保水剂具有显著的保肥效果，在一定程度上减少了可溶性养分的淋溶损失，从而对土壤的持肥能力有较明显的增加作用。