【摘要】 通过一个月的室内培养试验,研究在不同土壤与植物残体施用下接种蚯蚓对土壤团聚体分布、稳定性及土壤有机碳的影响。供试土壤为粘粒含量较低的潮土(86 g/kg)与粘粒含量较高的红壤(318 g/kg),试验前受试土壤的大团聚体全部人为破坏;供试植物残体为高碳氮比的玉米秸秆与低碳氮比的三叶草残体;供试蚯蚓为威廉腔环蚓(Metaphire guillelmi)。试验结果表明:不同土壤与植物残体施用下,蚯蚓对土壤水稳性团聚体分布、微团聚体分散性及土壤有机碳赋存的作用不同,潮土中施用两种植物残体时,接种蚯蚓均显著降低土壤粘粒分散率(P<0.05),但不对水稳性团聚体分布及团聚体平均重量直径(MWD)产生影响,同时赋存于粘粉粒中的有机碳含量均增加;红壤中施用两种植物残体时,接种蚯蚓均显著降低土壤粘粒及粘粉粒分散率(P<0.05),同时均形成>2 mm大团聚体,2～0.25 mm大团聚体所占比例及MWD也显著增加(P<0.05),相应赋存于>2 mm大团聚体与2～0.25 mm大团聚体中的土壤有机碳含量均显著增加(P<0.05)。两种土壤在施用植物残体且接种蚯蚓时均可显著增加土壤有机碳的含量(P<0.05)。对于水土流失和土壤结构严重退化的地区,通过施用植物残体并接种蚯蚓是恢复土壤结构与增加土壤有机碳储存的重要生态工程措施。更多还原

【Abstract】 A 30-days experiment was conducted to investigate the effects of earthworm activity on soil aggregates distribution,stability and soil organic carbon under different plant debris input in different soils.A soil(silt loam) with low-clay content and a soil(silt clay loam) with higher-clay content were chosen to be tested,all soils were sieved <0.25 mm to destroy all macro-aggregates.The debris used for test was maize straw with high carbon to nitrogen ratio and white clover residue with low carbon to nitrogen ratio.The earthworm Metaphire guillelmi was chosen for test.The results indicated that earthworm affect water-stable aggregates distribution,micro-aggregate dispersion and soil organic carbon distribution differently under different soil and plant debris input.Earthworm decreased the clay dispersion significantly(P<0.05) and had no effect on the distribution of water-stable aggregates and mean weight diameter(MWD),and increased the distribution of soil organic carbon in silt plus clay under two kinds of plant debris input in silt loam soil.Meanwhile,earthworm decreased the dispersion of clay and clay plus clay significantly(P<0.05) and formed >2 mm macro-aggregate,and increased the percentage of 2～0.25 mm macro-aggregate and MWD significantly(P<0.05),and increased the distribution of soil organic carbon in >2 mm and 2～0.25 mm macro-aggregate significantly(P<0.05) under two kinds of plant debris input in silt clay loam soil.The combinations of earthworm inoculation and plant debris input all increased soil organic carbon content significantly(P<0.05) in the two soils.Earthworm inoculation was helpful for the recovery of soil structure and the increment of soil organic carbon under plant debris input in these regions where soil erosion and soil structure degradation are serious.更多还原