不同施肥水平对桔梗土壤微生物和土壤酶活性的影响

Effect of fertilization levels on soil microorganism amount and soil enzyme activities

在陕西商洛香菊药源基地，采用氮，磷，钾3因素2次D一饱和最优设计施肥方案，研究氮磷钾不同施肥水平对桔梗土壤微生物数量和土壤酶活性的影响。结果表明，与N0P0K相比，N0P2K2，MP：K0，N3P1K3，N3P3K1，增加了0～2013113．土壤的细菌数量，分别增加了144．34％，39．25％，37．17％，53．58％；N3P1K3处理20—40cm土壤中细菌数量增加了163．77％；％Po玛显著提高土壤中放线菌的数量，比Ⅳ0PnK处理增加了192．11％，其他处理作用不显著；他N2P0K2和N3P1K3显著增加了0～20cm土壤真菌的数量，分别比％RK处理增加了35．27％，92．21％；几eoKo显著增加了20—40cm土壤真菌数量，增加了165．35％，其他处理较对照没有显著增加或者对真菌有不同程度的降低。除帆R砬外，施肥极显著降低了0—20cm土壤中过氧化氢酶活性，N2P2K0和氮磷钾三者配施（NPK）极显著增加了20—40em土壤中过氧化氢酶活性；施肥显著增强了20～40am土壤中蔗糖酶活性；施肥不同程度的降低了0～20am土壤中磷酸酶活性，除N，P，托处理外，施肥却增强了20—40cm土壤中磷酸酶活性；N3P0K0，N0P0K3，N2P0K2，N2P2K0，N3P1K3显著增强了0—20till土壤脲酶活性，分别比对照增加了18．22％，14．87％，17．84％，27．88％，24．54％。除％P2恐外施肥显著增强了20—40cm土壤脲酶活性。

Field experiments were conducted in Shangluo pharmaceutical base in Shaanxi province to study the effect of nitro- gen, phosphorus and potassium in different fertilization levels on Platycodon grandiflorum soil microorganism and activities of soil en- zyme, using three-factor D-saturation optimal design with random block design. The results showed that NoP2K2 ,N2P2Ko ,N3PiK3and N3P3K1 increased the amount of bacteria in 0-20 em of soil compared with NoPoKo by 144.34% , 39.25% , 37.17% , 53.58% , re- spectively. The amount of bacteria in 20-40 cm of soil of N3 P~ Kj increased by 163.77% , No PoK3 increased the amount of soil actino- mycetes significantly by 192. l 1% , while other treatments had no significant effect. N2PoK2and N3 P1K3increased the amounts of fun- gus significantly in 0-20 cm of soil compared with NO Po Ko, increased by35.27% and 92.21%, respectively. N3 P0 K0 increased the amounts of fungus significantly in 20-40 cm of soil by 165.35%, while other treatments had no significant effect. All treatments de- crease soil eatalase activity significantly in 0-20 em of soil except for N2PoK2, and while NzP2Koand NPK increased eatalase activity significantly in 20-40 em of soil. Fertilization regime increased invertase activity significantly in 20-40 em of soil, and decreased phos- phatase activity inordinately in 0-20 em of soil, while increased phosphatase activity in 20-40 cm of soil other than NjP3K3. N3PoKo, NoPoK3, N2PoK2, N2P2Koand NPK increased soil urease activity significantly in 0-20 em of soil compared with NoPoKo by 18.22%, 14.87%, 17.84 % ,27.88% ,24.54% , respectively. Fertilization regime increased soil urease activity significantly in 20-40 cm of soil other than NoP2K2.