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土壤动物是陆地生态系统的重要组成部分,为探讨不同土地利用类型土壤动物对土壤氮矿化过程的影响,以苏北沿海地区3种土地利用方式(杨树人工林、农田、杨农复合林)为研究对象,通过设置不同实验处理(对照、撒噻唑磷驱除土壤线虫、撒萘驱除所有土壤动物),采用顶盖埋管法测定土壤矿质氮的含量,分析了土壤动物对有机氮矿化速率的影响。结果表明:13种土地利用类型驱除土壤线虫和驱除所有土壤动物处理的土壤NO-3-N和总无机氮(TMN)含量均显著低于对照(P<0.05),说明土壤线虫和土壤动物的存在能显著提高土壤中NO-3-N和总无机氮的含量;而NH+4-N含量变化不明显。2土地利用类型和土壤动物类群数量的改变会影响土壤净氮矿化速率;0~10 cm土层,对照处理土壤净氮矿化速率从大到小表现为农田>杨树林>杨农复合林,驱除线虫和驱除所有土壤动物处理下均表现为杨农复合林>农田>杨树林;各处理≥10~25 cm土层动物变化不显著。且0~10 cm对照和驱除线虫处理,杨树林与农田间土壤净氮矿化速率差异显著(P<0.05,P<0.01)。驱除线虫和驱除所有土壤动物均能降低土壤净氮矿化速率(P<0.05)。3驱除所有土壤动物处理的土壤微生物量氮的含量极显著低于对照(P<0.01),表明驱除土壤动物对土壤微生物有极显著的影响。
Soil animals are an important part of terrestrial ecosystems. In order to explore the impact of soil animals of different land use types on soil nitrogen mineralization, three types of land use patterns (poplar plantation, farmland, ) As the research object, by setting different experimental treatments (control, soil thiamazole repellent soil nematode, naphthalene repellent removal of all soil animals), using top-buried tube method for determination of soil mineral nitrogen content of soil animal analysis of organic nitrogen mineralization Effect of rate. The results showed that soil NO-3-N and total inorganic nitrogen (TNN) contents of soil nematode and soil animal repellent were significantly lower than those of control (P <0.05), indicating that soil nematode and soil animal The content of NO-3-N and total inorganic nitrogen in soil can be significantly increased, while the content of NH + 4-N does not change obviously. The changes of land use types and the number of soil fauna affect the rate of soil net nitrogen mineralization. In 0 ~ 10 cm soil layer, the soil net nitrogen mineralization rate decreased from small to small in comparison with farmland> poplar forest> Under the conditions of repelling nematodes and exterminating all soil animals, all of them showed Yangnong compound forest> farmland> poplar forest; and the animals in ≥10 ~ 25 cm soil layer did not change significantly. The difference of net N mineralization rate between poplar forest and farmland was significant (P <0.05, P <0.01) with 0-10 cm control and repellent nematode treatment. Eradication of nematodes and removal of all soil animals reduced soil net nitrogen mineralization rate (P <0.05). 3 The content of soil microbial biomass nitrogen expelled by all soil animals was significantly lower than that of the control (P <0.01), indicating that exterminating soil animals had a very significant impact on soil microorganisms.