果草套种对南方丘陵山地表层土壤微生物量碳氮及酶活性的影响

目的]探究不同果草套种模式下0—10cm土层土壤微生物量碳、氮及酶活性的差异,为改善土壤肥力条件、促进桂林旅游城市生态循环农业经济的发展提供理论依据。方法]在桂林潮田河流域大山口农业综合示范区内设置样地,采集表层(0—10cm)土壤样品,测定与分析不同果草套种模式下表层土壤微生物量碳、氮及酶活性的差异。结果]0—10cm土层土壤氮磷钾、土壤微生物量碳氮和土壤酶活性大小基本表现为:阳朔金桔+牧草桂橙1号+牧草翠冠梨+牧草对照样地。其中,阳朔金桔+牧草模式对0—10cm土层土壤微生物量碳、氮含量和土壤酶活性的影响最为明显(p0.05)。相关性分析表明,土壤微生物量碳氮和3种土壤酶活性存在极显著正相关关系。结论]果草套种模式特别是阳朔金桔+牧草模式对南方丘陵山地表层土壤肥力条件的改善作用较为明显。

Effects of Fruit and Grass Intercropping on Soil Microbial Biomass C, N and Soil Enzyme Activities in Hilly Lands of Southern China

Objection] Differences of soil microbial biomass carbon, nitrogen and soil enzyme activities in different patterns of fruit and grass intercropping were compared in order to provide a support for soil fertility melioration and agriculture modernization.Methods] Top soil layer(0-10 cm) from four patterns of fruit and grass intercropping was sampled in sites of Dashankou comprehensive agriculture demonstration zone, which located at Chaotian watershed of Guilin area. Variance and correlation analyses were used to compare the differences of soil microbial biomass carbon, nitrogen and soil enzyme activities.Result] Soil total nitrogen, total phosphorus, total potassium and their available components, soil microbial biomass carbon, nitrogen and soil enzyme activities behaved almost similar ranks as:Fortunella margarita+grass >Guicheng No.1+grass >Pyrus spp+grass >control plot. Pattern of Fortunella margarita+grass intercropping had significant effects on soil microbial biomass carbon, nitrogen and soil enzyme activities(p<0.05). This pattern ameliorated soil better than other patterns did. There existed positive correlations between soil microbial biomass carbon, biomass nitrogen and soil enzyme activities.Conclusion] Fruit and grass intercropping, especially the pattern of Fortunella margarita+grass, had significant effects on soil amelioration in hilly lands in the southern of China.