断根和施肥对杨树人工林根际土壤肥力及生物学特性的影响

采用田间小区试验研究了不同的断根和施肥措施对I-107杨树人工林根际养分、微生物数量及酶活性的影响。结果表明:相同处理的杨树林地根际土壤pH均低于非根际土壤,而有机质、速效氮、速效磷、速效钾、有效铜和有效锌的含量均高于非根际土壤;与其它处理相比,断根施肥处理的根际土和非根际土壤速效养分含量最高,差异达显著水平;与对照相比,断根施肥处理显著提高了林地土壤的脲酶、转化酶、过氧化氢酶、多酚氧化酶和过氧化物酶活性,而施肥未断根处理少量增加了此5种土壤酶活性,断根未施肥处理则降低了土壤酶的活性。各处理林地土壤微生物数量大小次序为:断根施肥>施肥未断根>断根未施肥>对照。由此可得出,施肥和断根措施相结合可有效改善根系土壤环境,提高林地土壤肥力。

Effects of Cutting Roots and Fertilization on Soil Fertility and Bionomics in Poplar Plantation

The effects of different cutting roots and fertilization measure on soil nutrient,microbe quantity and enzyme activity both rhizosphere and non-rhizosphere soil in I-107 poplar plantation were studied by field plot experiment.Results showed that the pH value in rhizosphere soil of same treatments poplar plantation was lower than that in non-rhizosphere soil,but the content of organic,available nitrogen,available phosphorus,available K,utility cuprum and utility zincum were all higher than those in non-rhizosphere soil.The available nutrient content of cutting roots fertilizer treatment was significant more than other treatments both in rhizosphere and non-rhizosphere soil.Cutting roots fertilizer treatment increased the activity of soil urease,invertase,catalase,polyphenol oxidase,peroxidase significantly,compared with CK.Five soil enzyme activities by fertilizer treatment increased little,but cutting roots treatment decreased the activity.The quantities of microbe were orderly followed as cutting roots fertilizer,fertilizer,cutting roots,CK.The results implied that the measure of cutting roots fertilization may improve the root soil environment and enhance the plantation soil fertility.