为了解南方烟区土地整理后土壤肥力、土壤物理和微生物变化情况,对福建三明烟区整理前后烟田进行定点采样和室内检测,发现土地整理后土壤活性有机质、碱解N、有效P、速效K、重金属Pb、Cr含量等显著下降.土壤活性有机质、有效Cu、Zn含量在种植一季水稻后恢复到整理前的水平;碱解N、有效P、Fe含量在种植一季水稻和烤烟后(2年)能恢复到整理前的含量水平;速效K含量在种植烤烟后大幅度增加;重金属Pb、Cr含量在种植一季水稻后恢复到整理前的水平.土壤微生物数量及其多样性指数显著下降,细菌总量在一年后能恢复到整理前水平;真菌、放线菌和多样性指数在3年内没能恢复到整理前水平.水稳性团聚体含量显著下降,粒径大于1 mm团聚体含量能较快地恢复到整理前水平;而小粒径团聚体恢复更慢.土壤容重显著增加,最大持水量、非毛管孔隙度、土壤通气度、排水能力等显著下降.总之,土地整理后要有针对性地进行土壤改良,尽快恢复土壤理化性状和微生物生态.%Soil samples from selected locations at tobacco fields in Sanming, Fujian were collected for a study on the effects on the fertility, physical properties, and microbes in the soil after a land consolidation.The results showed that the contents of labile organic matters and available N, P and K, as well as active Pb and Cr, decreased significantly after the consolidation.The contents of labile organic matters and available Cu and Zn in the soil were rejuvenated to their original levels followed by a rice planting.The contents of available N, P and Fe would recover after two years with a rice and a tobacco planting.Available K increased largely after a season of tobacco planting, while active Pb and Cr took one rice planting for a recovery.The microbial population and diversity index of the soil decreased upon a land consolidation.The count on bacteria recuperated in a year;but, for fungi and actinomycetes, their numbers did not recover in 3 years.The percentage of the moisture-holding-aggregates in the soil decreased significantly, particularly for those with a diameter of 1 mm or larger but not for the smaller ones.The bulk density of the soil significantly increased, while the maximum moisture capacity and other physical characteristics decreased.In conclusion, after a land consolidation timely and adequate adjustments on the soil should be implemented to ensure a healthy recovery of the field for future planting.
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