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Title
  • en Assessing the impact of phosphorus cycling on river water P concentration in Hokkaido
Creator
    • en Woli, Krishna Prasad
    • en Hayakawa, Atsushi
    • en Nagumo, Toshiyuki
    • en Imai, Hiromu
    • en Ishiwata, Teruo
Accessrights open access
Rights
  • en The definitive version is available at www.blackwell-synergy.com
Subject
  • Other en phosphorus concentration
  • Other en phosphorus budget
  • Other en river water quality
  • Other en surplus phosphorus
  • Other en topography
  • NDC 613
Description
  • Abstract en We estimated the phosphorus (P) budgets for all 212 cities, towns and villages of Hokkaido, Japan. We also carried out water sampling from all major rivers flowing in the respective areas during the snowmelt season and measured total P (TP) concentration. Surplus P in the agricultural land was estimated by subtracting the amount of crop uptake from the input sources, such as the amount of chemical and compost fertilizers, crop residues, rainfall and irrigation. The livestock excreta P not utilized on farmland was assumed to be disposed P. Total P concentrations in most of the river water ranged from undetectable to 1 mg L-1, rarely reaching up to 2.32 mg L-1, and the areas surrounding the Funka Bay had comparatively higher concentrations. More than two-thirds of the areas had surplus P in farmland ranging from negative values to 30 kg ha-1 of farmland, and areas with mixed farmland and livestock husbandry had higher surplus values ranging from 31 to 72 kg ha-1, indicating that the source of the residual P was applied chemical and manure fertilizers. Total P concentration in river water was not correlated with the proportion of upland field and urban area or with the farmland surplus P resulting from the P cycling and the municipal waste P that mixes into the river water. However, TP concentration was positively correlated with the proportion of Andisol area occupied by farmlands (r = 0.25, P < 0.01). The TP concentration was also correlated with the topographic factors in areas (r = 0.49, P < 0.01) that possess more than 50% Andisols in farmlands. Multiple regression analysis showed that TP concentration was best explained by a combination of disposed excreta, the Andisol area occupied by farmland, the application rate of chemical fertilizers and topographic factors (r2 = 0.21, P < 0.001). Thus, P losses from farmlands to river water during the snowmelt season could mainly be attributed to fertilizer management and soil type along with the topographic condition of the area.
Publisher en Blackwell Publishing
Date
    Issued2008-04-01
Language
  • eng
Resource Type journal article
Version Type AM
Identifier HDL http://hdl.handle.net/2115/38123
Relation
  • isVersionOf DOI https://doi.org/10.1111/j.1747-0765.2007.00243.x
Journal
    • PISSN 0038-0768
    • EISSN 1747-0765
    • NCID AA00844314
      • en Soil Science & Plant Nutrition
      • Volume Number54 Issue Number2 Page Start310 Page End317
File
    • fulltext woli-4.pdf
    • 632.36 KB (application/pdf)
      • Issued2008-04-01
Oaidate 2023-07-26