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在大田条件下,研究了UV-B辐射增强及不同施氮水平下,大麦不同生育期根际和非根际土壤纤维素酶、碱性磷酸酶和脲酶活性的动态变化。UV-B辐射设2水平,即对照(CK,自然光,12.0 kJ m-2d-1),增强20%(Elevated,14.4 kJ m-2d-1)。施氮量设3水平,即30、150和300 kg hm-2。结果表明:与对照相比,UV-B辐射增强对大麦根际土壤纤维素酶、碱性磷酸酶和脲酶活性的影响,因生育期和施氮量而异。中高氮下,UV-B辐射增强可降低根际土壤纤维素酶、碱性磷酸酶和脲酶活性,而低氮下UV-B辐射增强则提高相应酶活性,但UV-B处理间差异大多不显著。在UV-B辐射增强下,随施氮量增加,根际土壤纤维素酶活性下降,而碱性磷酸酶和脲酶活性呈先降后升趋势,但施氮量处理间差异大多不显著。根际土壤酶活性与非根际土壤相比,既有升高也有下降。研究认为,UV-B辐射增强尚不足以对大麦根际土壤纤维素酶、碱性磷酸酶和脲酶酶活性产生显著影响,这可能与设定的UV-B辐射强度、试验方法及采样方法有关。
Under field conditions, the dynamic changes of cellulase, alkaline phosphatase and urease activities in rhizosphere and non-rhizosphere soil of barley under different levels of nitrogen and nitrogen were studied under UV-B radiation. The level of UV-B radiation was set at 2 levels (CK, natural light, 12.0 kJ m-2d-1) and increased by 20% (Elevated, 14.4 kJ m-2d-1). Nitrogen rates were set at 3 levels, ie 30, 150 and 300 kg hm-2. The results showed that compared with the control, the effect of UV-B radiation on the activities of cellulase, alkaline phosphatase and urease in rhizosphere soil of barley varied with the growth period and nitrogen application rate. Under medium-high nitrogen, enhanced UV-B radiation could reduce cellulase, alkaline phosphatase and urease activity in rhizosphere soil, but increased UV-B radiation at low nitrogen level, but the differences between UV-B treatments were mostly not Significant. Under UV-B radiation enhancement, with the increase of nitrogen application rate, cellulase activity of rhizosphere soil decreased, but alkaline phosphatase and urease activity decreased first and then increased, but the differences between the two treatments were not significant. Rhizosphere soil enzyme activity compared with non-rhizosphere soil, both increased and decreased. The study suggests that enhanced UV-B radiation is not enough to significantly affect the activity of cellulase, alkaline phosphatase and urease in rhizosphere soil of barley, which may be related to the set UV-B radiation intensity, test methods and sampling methods .