【摘要】 为了解决沼液资源化利用,化肥减施的问题,该文以沼液替代化肥来研究相同氮磷钾含量肥料施用的前提下,不同沼液用量与化肥配合施用（N₁P₁K₁Z₁—沼液全氮替代化肥施氮总量的25%,N₂P₂K₂Z₂—沼液全氮替代化肥施氮总量的50%,N₃P₃K₃Z₃—沼液全氮替代化肥施氮总量的75%）对毛竹林地土壤理化性质及竹林固碳增汇效应的影响。结果表明,单独施用化肥或者化肥与沼液配合施用对毛竹林地土壤pH值、有机质、全氮、磷、钾含量的影响不明显（P>0.05）,而沼液与化肥配合施用（特别是N₃P₃K₃Z₃—高量沼液）对土壤碱解氮、有效磷、速效钾含量提高的幅度较为显著（单施化肥处理除外）（P<0.05）。单独施用化肥或化肥与沼液配施显著降低了放线菌的比例（单施化肥处理除外）,却显著增加了细菌和真菌的比例（P<0.05）。与不施肥对照CK处理相比,单施化肥处理显著增加了细菌与真菌数量的比值,增幅为24.51%;而沼液与化肥配施则与CK处理之间的差异不显著（P>0.05）。化肥与沼液配施均能显著提高毛竹林地土壤微生物量碳和氮的含量,而且能够显著提高土壤蔗糖酶、脲酶、过氧化氢酶的活性（P<0.05）,各施肥处理均以N₃P₃K₃Z₃提高的幅度最大。此外,单独施用化肥或者化肥与沼液配施均能显著提高I度竹、II度竹和林分的平均胸径以及I度竹和林分的碳储量（P<0.05）,各施肥处理仍以N₃P₃K₃Z₃处理增加的幅度最大。可见,施用沼液替代化肥能够提升土壤肥力水平,促进毛竹生长,尤其是新竹的生长和固碳增汇。更多还原

【Abstract】 In order to solve the problem of resource utilization of biogas slurry and the reduction of chemical fertilizers, in this study, we worked on the effects of combined application of different biogas slurry dosages and chemical fertilizers（all treatments receiving the same amount of NPK application） on soil physical and chemical properties and carbon sink enhancement of bamboo forest. The result showed that the solo application of chemical fertilizers（NPK treatment） or combined application of biogas slurry and chemical fertilizers（N₁P₁K₁Z₁—total nitrogen in biogas slurry replaced 25% of the total application amount of chemical fertilizer, N₂P₂K₂Z₂—total nitrogen in biogas slurry replaced50% of the total application amount of chemical fertilizer, N₃P₃K₃Z₃—total nitrogen in biogas slurry replaced 75% of the total application amount of chemical fertilizer） had no obvious effects on the soil pH values and the contents of soil organic matter, total nitrogen, total phosphorus and total potassium（P>0.05）, while the combined application of biogas slurry and chemical fertilizers（especially N₃P₃K₃Z₃ treatment-high dosage biogas slurry） significantly increased the contents of soil alkali hydrolyzable nitrogen, available phosphorus, and available potassium（P<0.05）. Compared to the CK treatment, solo application of chemical fertilizers slightly decreased the proportion of actinomycetes（P>0.05）, while the combined application of biogas slurry and chemical fertilizers significantly decreased the proportion of actinomycetes（P<0.05）, and significantly increased the proportions of bacterial and fungi, respectively（P<0.05）. Relative to the CK treatment, NPK treatment significantly increased the ratio of bacteria to fungi by 24.51%（P<0.05）, while the combined application of biogas slurry and chemical fertilizers decreased the ratio of bacteria to fungi to different degrees with no significant difference（P>0.05）. Solo application of chemical fertilizers had no significant effects on the contents of soil microbial biomass carbon and nitrogen of bamboo forest（P>0.05）, but the combined application of biogas slurry and chemical fertilizers significantly increased the contents of soil microbial biomass carbon and nitrogen by 19.3%-62.0% and 52.7%-147.3%, respectively（P<0.05）. Compared to the CK treatment, solo chemical fertilizers or combined application of biogas slurry and chemical fertilizers significantly decreased the ratio of soil microbial biomass carbon to microbial biomass nitrogen（P<0.05）. The solo application of chemical fertilizers had no significant effect on invertase activity（P>0.05）, but the combined application of biogas slurry and chemical fertilizers significantly increased the invertase activity by 46.2%-138.5%（P<0.05）. The solo application of chemical fertilizers or combined application of biogas slurry and chemical fertilizers significantly improved urease activity by 7 to 14.5 times compared to the CK（P<0.05）. Application of fertilizers significantly increased the acid phosphatase activity in the NPK and N₁P₁K₁Z₁ treatments compared to the CK, respectively（P<0.05）, but no significant difference was found among CK, N₂P₂K₂Z₂ and N₃P₃K₃Z₃ treatments. There were no significant（P>0.05） difference among the CK, NPK, N₁P₁K₁Z₁ and N₂P₂K₂Z₂ treatments of catalase activity. In summary, the combined application of biogas slurry and chemical fertilizers could significantly increase soil available nutrient contents, the proportions of bacterial and fungi, soil microbial biomass carbon and nitrogen, and the activity of invertase, urease and catalase. In all fertilization treatments, the increase of above indicators under N₃P₃K₃Z₃ treatment was the most obvious. In addition, all fertilization treatments significantly increased the mean diameter at breast height of one-year bamboo, two-year bamboo and bamboo stand by 38.9%-61.7%, 11.8%-18.8%, and 13.1%-24.4%, respectively（P<0.05）. In addition, all fertilization treatments significantly increased carbon storage of one-year bamboo and bamboo stand by 41.5%-179.0% and 26.3%-39.0%, respectively（P<0.05）. For all fertilization treatments, the increase of mean diameter at breast height and carbon storage of one-year bamboo under N₃P₃K₃Z₃ treatment was the most obvious. It could be seen that the combined application of biogas slurry and chemical fertilizers could increase soil fertility, promote the growth of bamboo（especially newly grown bamboo） and increase carbon sequestration of bamboo.更多还原