4种熏蒸剂对土壤硝化作用及相关酶活性的影响

Effect of Four Fumigants on Soil Nitrification and Related Enzyme Activity

以北京市顺义区黄瓜、番茄轮作3 a 以上的温室土壤为对象,采用室内恒温通气培养法,研究氯化苦（Pic）、1,3- 二氯丙烯（1,3-D）、二甲基二硫（DMDS）和威百亩（MS）等4 种熏蒸剂对土壤硝化作用和几种相关酶活性的影响,并对Pic 处理中可能影响硝氮含量变化的-些指标进行了相关性分析.结果表明：4 种熏蒸剂处理均对土壤硝化作用有明显抑制作用,其中Pic、1,3-D 和MS 处理对土壤硝化作用的抑制持续28～56 d,而DMDS 的抑制作用只有7 d 左右;Pic 对土壤蛋白酶活性表现出显著的增强作用,而MS 则对蛋白酶活性有强烈的抑制作用;各熏蒸剂处理对土壤谷氨酰胺酶和天冬酰胺酶均表现出不同程度的抑制作用.Pic 处理土壤硝氮（NO3^--N）与铵氮（NH4＋-N）、可溶性有机氮（DON）的相关系数分别为-0.977 和0.887,均达极显著水平;与可溶性氨基酸（DAA）和土壤微生物量氮（SMBN）相关系数分别为-0.628 和-0.645,均达显著水平.

Taking soil which cucumber,tomato rotation for more than 3 years in Shunyj Djstrict of Beijing vegetable greenhouses as research object,and adopting the method of indoor constant temperature with aerated condition,this paper studied the effects of 4 fumigants Chloropicrin(Pic),1,3-Dichloropropene(1,3-D), methyl disulfide(DMDS)and methamsodium(MS)on soil nitrification and several related enzyme activities. The paper also conducted correlation analysis on certain targets,which might influence the contents of nitrate nitrogen in Pic treatment group. The results revealed that soil nitrate nitrogen concentration decreased significantly after all these 4 fumigantion treatments.Among them,the inhibition on soil nitrification by Pic,1,3-D and MS treatments could last for 28-56 days,while the DMDS treatment could only last about 7 days.All fumigation treatment showed different inhibition levels on soil glutamine enzyme and asparagine enzyme.Pic showed significant promoting effect on soil protease activity,while on the contrary MS showed strong inhebitory effect. The correlation coefficients between NO3--N and NH4+-N,NO3--N and DON,NO3--N and DAA,NO3--N and SMBN were -0.977,0.887,-0.628 and -0.645,respectively and all of the correlation reached significant or very significant level.