2024-03-29T14:57:13Z
https://tsukuba.repo.nii.ac.jp/oai
oai:tsukuba.repo.nii.ac.jp:00038190
2022-04-27T09:07:52Z
160:2169
3:62:5601:2078
Characterisation of soils under long-term crop cultivation without fertilisers: a case study in Japan
田村, 憲司
Nakatsuka, Hiroko
Tamura, Kenji
Certain farms in Japan, namely unfertilised farms (UFs), have been able to maintain high productivity for over 40 years without applying fertilisers or composts. This study aimed to characterise the physicochemical, biological and micromorphological properties of soil in UFs compared with control farms in Eniwa and Nariita and to identify characteristics that are associated with crop productivity. In UFs, no plough pan was observed. The thickness of the effective soil depth (ESD) of UFs was greater than that of CFs. The concentrations of soil organic carbon, total nitrogen and nitrate-nitrogen in ESD of UFs were higher than those in ESD of CFs. Soil microstructure observations indicated the strong development of a granular microstructure with large amounts of void space and a high fractal dimension in both surface and subsoil horizons of UFs. Dry yield had a strong correlation with ESD thickness and fractal dimension of voids. Thus, the management of unfertilised cultivation promoted the development of soil aggregation in both A and B horizons. The increase in ESD, soil pore spaces and complexity with the development of subsoil structure improved the productivity of unfertilised cultivation.
journal article
Springer
2016-03
application/pdf
SpringerPlus
5
283
2193-1801
https://tsukuba.repo.nii.ac.jp/record/38190/files/SP_5-283.pdf
eng
27047709
10.1186/s40064-016-1917-y
© 2016 Nakatsuka and Tamura. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.