不同生态恢复方式及施肥管理对退化黑土物理性状的影响

Effects of Ecological Restoration and Fertilization Management on Physical Properties of Degraded Black Soil

研究了不同生态恢复方式(苜蓿休闲、自然恢复、种植作物)和不同施肥管理(化肥+有机肥、化肥+秸秆还田、化肥、无肥)对退化黑土物理性状的影响。结果表明,与自然恢复相比,不同施肥管理对退化黑土物理性状改良效果皆较好,表现为容重减小,孔隙度、毛管持水量、最大持水量、田间持水量和水稳性团聚体含量增加,其中化肥与有机肥配施效果最好;而苜蓿休闲方式由于恢复年限较短,仅容重和孔隙度变化较明显。苜蓿和自然恢复对0—10 cm土层的容重、总孔隙度、毛管持水量、最大持水量、田间持水量影响较大,而10—20 cm土层由于恢复年限较短,变化不明显。0—20 cm土层水稳性团聚体(>0.25 mm)含量和平均重量直径表现为不同施肥管理>苜蓿休闲>自然恢复。

The effects of different kinds of ecological restoration （alfalfa fallowing, natural vegetation restoration, and cropping） and fertilization management （chemical fertilizer ＋ organic manure, chemical fertilizer ＋ straw, chemical fertilizer application, and no fertilizer application） on the physical properties of degraded black soil were investigated. Results showed that fertilization management decreased soil bulk density, but increased porosity, capillary capacity, max moisture capacity, field water capacity, and the content of watersable aggregates as compared with natural vegetation restoration. Chemical fertilizer, together with organic manure, significantly improved them as compared with other fertilizer treatments. However, significant difference was only observed between alfalfa fallow and natural vegetation restoration in terms of bulk density and porosity due to short time of ecological restoration. Bulk density, porosity and capillary capacity, max moisture capacity, and field water capacity changed greatly in 0-10 cm soil layer as compared with them in 10-20 cm soil layer. Both the content of water-stable aggregates （〉0.25 mm） and the mean weight diameter increased in the ascendant order of natural restoration, alfalfa fallow, and fertilization management.