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131.
Effect of rotation, nitrogen fertilization and management of crop residues on some chemical, microbiological and biochemical properties of soil 总被引:4,自引:0,他引:4
P. Perucci U. Bonciarelli R. Santilocchi A. A. Bianchi 《Biology and Fertility of Soils》1997,24(3):311-316
A long-term experiment, which started in 1971 near Perugia, central Italy, was performed to investigate the effect of different
crop residue management practices and rotation systems on some soil properties. Twenty years after the beginning of the experiment,
chemical (organic C, total N, humified organic C, humic and fulvic acids), microbiological and biochemical parameters (microbial
biomass, global hydrolase activity, dehydrogenase and catalase activities) were investigated. Two crop residue management
practices were used in the experiment, i.e. removal (RCR soils) and burial (BCR soils). These treatments were factorially
combined with eight rotation systems, i.e. five maize-wheat rotations of different lengths (M-1W, M-2W, M-3W, M-4W and M-5W)
and three continuous wheat systems with different fertilization inputs, from 150 to 250 kg N ha–1. Soil samples were collected in the spring of 1991 for chemical determinations, and in the spring and autumn of 1992, 1993
and 1994, for microbiological and biochemical determinations. All soil chemical, microbiological and biochemical parameters
investigated showed significant differences depending on the management of the crop residues. The BCR soils showed more favourable
characteristics. In contrast, few significant effects were observed in relation to rotation and N-fertilization treatment.
Significant correlations were found between organic-C content and all microbiological and biochemical parameters, as well
as between the microbiological and biochemical parameters themselves, indicating that organic-C content plays an important
role in determining the level of soil enzyme activity and, consequently, of soil fertility. This experiment showed that burying
crop residues in soil can be considered good agronomic practice, which may help limit the gradual depletion of soil organic
matter and improve the chemical properties of the soil.
Received: 11 January 1996 相似文献
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What's in an index? Comparing the ecological information provided by two indices to assess the status of coralligenous reefs in the NW Mediterranean Sea 下载免费PDF全文