J. Jpn. Soc. Soil Phys. No. +*-, p.1+12,**0 * Hydrologic Process in Wetland Characteristics of a Mire in a Snowy Region Makoto NAKATSUGAWA** ** Toyohashi O$ce of River Works, Chubu Regional Development Bureau, Ministry of Land, Infrastructure and Transport, Aza Hiranishi +0, Nakano-cho, Toyohashi..+2+.3 + +300 +322 Bog + - Bog, +33*,**/, +./*/ +.++*,1 km / km2 km +.,0** ha +.0 km, -,*** ha -* km, +331 +2 m *..+2+.3 +0 :
72 +*-,**0,/* ha,./ km, 2./ +-.. m +331,**. +311,*** IKONOS,,- - Fig. + + Map of Sarobetsu river basin -. H2B- H2B, H2B+ +,*** H2B+ H2B, H2B-. H2B+ H2B, / H2B+ +331,*** +. Fig.,, +311,*** Analysis area (left) and change in mire vegetation (right) (Black part in analysis area in right figure changed from wetland to sasa bamboo between +311 and,***)
: 73 - Fig. - Neighboring area around the visitor center (White circles show groundwater wells) 02,**, +,**. - +2 0.,*** Fig.. Variations of river water level and groundwater level near the visitor center (Daily average in,***) / +330,*** Fig. / Groundwater level and depth of snow pack near the visitor center (Monthly average from +330 to,***)
74 +*-,**0. 0 Fig. 0,**,,**. Relationship of water equivalent of snow between Toyotomi site and sites in mire based on field survey from,**, to,**. mm, 1 km +, m, - m, 1 m b m b +a*ids* Dt a *i *.1 DS * ttdt tt mm Dt days +, m b *.3/ mmd + mmd.+, ( (h T (x (x ( (h (h T q*s (y (y (t h m T m, s k ms m S q * ms FEM +33* FEM f h h N h i w i w i M e f i i+ i N e M w i e ( (h T (x (x ( (h T (y (y q*s (h (t e ew i dxdy* x, y e w * h N P ijh j+ j N j+ e+ (h j R ij Fj* (t h P ij M e e+ R ij M F ie M e T e (fi (x (f j e (x e+ e Se f ie f je dxdy e+ T e (fi e (y e dxdy qfie f ie q n ds (f j e (y dxdy -, s q n m, s Pinder et al. +311 +321
: 75 R Dt P htdt R Dt htf P R F + /** m +,3*- +,*/+ +day 20,.** sec.,,**-,**. T, Gauss-Newton +*. +*, md S *.,/ ROKMTResidual Ordinary Kriging with Modified Trend +331 +* +332 +333,***,,**, + *.+0 q * q * 3** mmyr /** mmyr 1** mmyr *.+0 ++* mmyr 2. * m / /+ + / km, 1 ROKMT,***. 2. 1 1 Fig. 1 2 Fig. 2,***. ROKMT Calculation of ground water level on April,*** (Dashed line shows interpolated result of measured data using ROKMT method and solid line shows calculated result),***. 1 Change in ground water level to di#erence of hydrologic condition between April and September in,***
76 +*-,**0 +*. +*, md /,,**. + mmd + mmd, mm d, 3,***,, mmd + mmd + mmd / cm. H2B+ cm +333,***,. +** mm +*,***. +** mm, ++. + + 0 1.* +, 2* 3* 3 Fig. 3,***,, mmday lmmday The di#erence in the simulated groundwater levels due to the change in snow melting recharge rates from + mm/day to, mm/day at the bottom of snow pack +* Fig. +*,***. +** mmmon Change in ground water level to decrease of snow melt of +** mm/month
: 77 ++ Fig. ++ +31+,*** Monthly averaged water level of Sarobetsu river from +31* s to +33* s at the Kaiunbashi site + + mmd, cm - +, Fig. +, +30+,*** Time series of annual maximum depth of snow pack at Wakkanai site based on date from +30+ to,*** /- ++ +.,***.,*** 1 2 +.-- m,**- : +0. : -.3-01. +331 : +33.+33/ : /31+. P.S. G.F. +321 : pp. 102*,**. : 0+, : -,*.
78 +*-,**0 W. +33* : pp. 12++3,**, : /22 : +3-2.,**/ :.3 : 13 2.. Pinder, G.F. and Gray, W.G. (+311) : Finite element simulation in surface and sub-surface hydrology, p.,3/, Academic Press, New York. +300 : - -1 2 :.+/.,+. +322 : +0 + : 1*2+., :,**/ ++ 1 :,**0,,2