College of Resources and Environment, Huazhong Agricultural University, Wuhan, China.
Sci China Life Sci. 2011 Jun;54(6):572-9. doi: 10.1007/s11427-011-4175-9. Epub 2011 Jun 26.
The sudangrass (Sorghum sudanense) and ryegrass (Lolium multiflorum L.) rotation is an intensive and new cropping system in Central China. Nutrient management practices in this rotation system may influence soil fertility, the important aspects of which are soil biological properties and quality. As sensitive soil biological properties and quality indicators, soil microbial community activity, microbial biomass, enzyme activities, soil organic matter (SOM) and total N resulting from different fertilization regimes in this rotation system were studied through a four-year field experiment from April 2005 to May 2009. Treatments included control (CK), fertilizer phosphorus and potassium (PK), fertilizer nitrogen and potassium (NK), fertilizer nitrogen and phosphorus (NP) and a fertilizer nitrogen, phosphorus and potassium combination (NPK). Soil microbial community activities in the NK, NP and NPK treatments were significantly lower than those in the CK and PK treatments after the sudangrass and ryegrass trial. The highest microbial biomass C, microbial biomass N, SOM, total N, sucrase and urease activities were found in the NPK treatment, and these soil quality indicators were significantly higher in the NK, NP and NPK treatments than in the PK and CK treatments. Soil microbial biomass and enzyme activities were positively associated with SOM in the sudangrass and ryegrass rotation system, indicating that fertilization regimes, especially N application, reduced microbial community activity in the soil. Proper fertilization regimes will increase microbial biomass, enzyme activity and SOM and improve soil fertility.
苏丹草-黑麦草轮作是中国中部地区一种密集且新颖的种植制度。该轮作体系中的养分管理措施可能会影响土壤肥力，其中重要的方面是土壤生物特性和质量。通过 2005 年 4 月至 2009 年 5 月为期四年的田间试验，研究了该轮作体系中不同施肥制度下土壤微生物群落活性、微生物生物量、酶活性、土壤有机质（SOM）和全氮的变化。处理措施包括对照（CK）、磷钾肥（PK）、氮肥和钾肥（NK）、氮磷肥（NP）和氮磷钾复合肥（NPK）。苏丹草-黑麦草试验后，NK、NP 和 NPK 处理的土壤微生物群落活性明显低于 CK 和 PK 处理。在 NPK 处理下，土壤微生物生物量 C、微生物生物量 N、SOM、全氮、蔗糖酶和脲酶活性最高，NK、NP 和 NPK 处理的这些土壤质量指标明显高于 PK 和 CK 处理。在苏丹草-黑麦草轮作体系中，土壤微生物生物量和酶活性与 SOM 呈正相关，表明施肥制度，特别是氮肥的应用，降低了土壤微生物群落的活性。适当的施肥制度将增加微生物生物量、酶活性和 SOM，从而提高土壤肥力。
