32 research outputs found
å¹²æå°åå£ã«ãããæ°Žååžçç¹æ§ãšãã®ç©çæ§ãžã®åœ±é¿
The concept of water potential (p.F.), as the index to characterized the condition and the nature of the soil water, turned out to be of importance in dealing with the soil in sea land reclamation area. The nature of water adsorbed at high p.F. range and its effects on physical properties of soil has been clarified using 75 samples in 16 sites from 4 different sea land reclamation areas. The results obtained suggest that the surface charge represented by cation exchange capacity (C.E.C.) has definite effect on the adsorption of water at p.F. 6.35, which in turn is considered to be the measure of specific surface area. The effects of electrolyte concentration on the amount of adsorbed water at p.F. 4.85 and 5.51 was very significant. The consistency limits were used to represent the physical properties of soil and the changes of these limits were interpreted in terms of change in the amount of adsorbed water at high p.F. range. Significant correlation was found between the consistency limits and the amount of water adsorbed at p.F. 4.85
Study on the Increase and Decrease of the Percolated Water Quantity in the Paddy Fields around the Lake due to the Variation of Water Level of the Lake
æ°Žè³æºã®æå¹å©çšãèšãäžç°ãšããŠ,åŸæ¥èŸ²æ¥çšæ°ŽæºãšããŠã®ã¿å©å ããŠããæ¹æ²Œããããããªåã§å€ç®çãªæ°Žå©çšããªãããããã«ãªã,åŸæ¥ãããæ¥æ¿ãªæ¹é¢æ°Žäœã®å€åãããè¿ãããããã«ãªã£ãŠããŠãããã®ãå€ã. ãã®çµæ,æ¹é¢æ°Žäœã®äœäžã«ããåšèŸºæ°Žç°ã®æµžééãå¢å ããããšã«ãªã,氎管çã®é¢ããçš®ã
ã®åé¡ãã²ããããããããã«ãªã£ã. ãããã®é¢ä¿ãæããã«ããã«ã¯ãŸã,åšèŸºæ°Žç°åå±€æ§æãªã©ãé©ç¢ºã«ææ¡ããããšãç¬åã§ãããšããã,äžè¬ã«ã¯åå±€æ§æã¯è€éã§ããããå³å¯ãªè§£æã¯å°é£ã§ãã. ããã§ç¬¬äžæ®µéãšããŠ,åçŽåããäºå±€æ§é ã¢ãã«ãèšå®ããŠ,äžå±€ãåéæ°Žæ§å±€(äœåå±€)ãšäžå±€ãè¯éæ°Žæ§å±€(å¿åå±€)ãšã®æ¡ä»¶ã«ãã£ãŠåºç€åŒãèªå°ãèªå°ããåºç€åŒã«äžäºäŸãšããŠ,å®æž¬ããããã€ãã®æ°å€ãå
¥ããŠ,ããã«ãã£ãŠæ¹æ°ŽäœäœäžéãšåšèŸºæ°Žç°ã®å¢å 浞ééãšã®é¢ä¿ãªãã³ã«æ°Žäœäœäžã«ãã£ãŠãããå¢å 浞ééã®åœ±é¿ããæ¹å²žããã®è·é¢ãªã©ã«ã€ããŠæ€èšãšèå¯ãè¡ãªã£ã. ãããã®çµæã«ã€ããŠç€ºãã°æ¬¡ã®ããã«èŠçŽããã. 1)æ¹é¢æ°Žäœå·®h0mã§ããå Žå,åšèŸºæ°Žç°ã®æ¹å²žxm,é¢ããå°ç¹ã«ããã浞é匷床qã¯æ¬¡ã®ããã«èªå°ããã. q=-F1h0e-ax 2)äžå±€d1ã®ãã¡,éæ°Žä¿æ°k1ã®å°ããåæ§ã»ã©æµžé匷床ã¯å°ãããæ¹é¢äœäžã«ãã浞ééå¢å ã®åœ±å¯©ã¯æ¹å²žããé æ¹ãŸã§ããã·ããšãããã,éã«éæ°Žæ§k1ã®å€§ããåæ§ã®å Žåã¯,æ¹å²žã§ã®æµžé匷床ã®æžå°ããçãé«ã. äŸãã°æ¹é¢æ°Žäœã1mäœäžããå Žå,浞é匷床q=10mm/dayã®å°ç¹ã¯æ¹å²žãã,äžå±€d1ã®éæ°Žä¿æ°ãk1=1Ã10-4cm/secã®å Žåã«ã¯21måããk1=5Ã10-5cm/secã®å Žåã«ã¯28mã§ãã£ã. 3)ãŸã,æ¹é¢æ°Žäœå·®ã倧ãããªãã°ãªãã»ã©,ãŸãk1ã®å€§ããã»ã©æµžé匷床ã倧ãããªã. äŸãã°å²¬ã®æµžéä¿æ°ãk1=Ã10-4cm/secã®å Žåã«ã¯,æ¹é¢æ°Žäœå·®h0=2m,3m,4m,5mã®ããããã®å Žåã«ã€ããŠæµžé匷床q=10mm/dayãäžå¿ã®å€å®åºæºã«ããå Žå,ããããã®h0ã«å¯Ÿããæ¹å²žããã®åœ±é¿è·é¢ã¯41m,48m,53m,57mã§ãã£ã. åæ§ã«d1å±€ã®éæ°Žä¿æ°k1=5Ã10-5cm/secã®å Žåã«ã€ããŠã¯,æ¹å²žããã®åœ±é¿è·é¢ã¯40m,50m,57m,62mã§ãã£ã. ããã«d1å±€ã®éæ°Žä¿æ°k1=1Ã10-5ã/secã®å Žåã«ã¯,h0=1m,2mã®å Žåã«ã¯éæ°Žä¿æ°ãã®ãã®ãå°ããã®ã§q=10mm/day以äžã§å€åããŠããã®ã§,æ°Žäœå€åå·®h0ã3m,4m,5mã®ããããã®å Žåã«ã€ããŠæ¹å²žããã®åœ±é¿è·é¢ãæ€èšããŠã¿ããš21m,37m,46mã§ãã£ã. 4)以äžããäžè¬ã®é©æ浞ééãšããããæ°Žç°ã§ãããæ°Žäœå€å5mäœãèãããšãã®åœ±é¿è·é¢ã¯ããã60mãŸã§ãšèãããã
Study on the Duty of Water in Flat and Lower Area of Paddy Fields by Water Balance
æ°Žç°ããã®æµžéæ°Žã¯å埩å©çšããããã®ã§å±å°çãªæžæ°Žæ·±ãšããããé¢ç©ããç®å®ããæ°Žéããã£ãŠåºåã®çšæ°Žéãšããããšã¯,éå°ã«çšæ°Žéãã¿ããããšã«ãªãã®ã§,æ°Žè³æºã®æå¹å©çšã®èŠ³ç¹ãããã£ãŠã奜ãŸãããªã. ããã«åºå°åã察象ã«ããããããèšç»ãæš¹ç«ããéã«ã¯æ°Žåæ¯ã«ãã£ãŠçšæ°Žéã決å®ããããšãåççãªæ¹æ³ãšããã. 以äžã®èŠ³ç¹ãã,äœå¹³å°æ°Žç°å°åž¯ã®æ°Žåæ¯ã«ããçšæ°Žéã®å®æ
調æ»ãè¡ãªã£ãçµæ,次ã®è«žç¹ãæãããšãªã£ã. 1)ãŸã,æ°Žåæ¯åŒã¯ (Q2-Q1)+(G2-G1)+en,+â¿S=0 äžåŒäž,(G2-G1)+en,tn+â¿Sãåºåæ°Žç°ã®æ¶è²»æ°Žéãšãªã. äžè¬ã«äœå¹³å°ã§ã¯(G2-G1)â0 æ°Žéã®å®å®ããæéã§ããã°â¿Sâ0ãšã¿ãªãããã,æ¬å°åã®ãããªæã§ã¯æ¶è²»æ°Žéã¯en,tnãšèãããã. 2)äžæ¹,ã¢ãã«å°åºå
ã®æµéå®æž¬ããŒã¿ããæ°Žåæ¯èšç®ã«ãã£ãŠæ±ããæ¶è²»æ°Žéã¯,Iã®æé(7æ18æ¥ïœ22æ¥)ã§ã¯æ°Žæ·±ã«ãªãããŠ,11.8mmday,Iã®æé(8æ10æ¥ïœ14æ¥)ã§ã¯11.0mm/day,â
¢ã®æé(9æ7æ¥ïœ11æ¥)ã§ã¯7.1mm/dayã®å€ãšãªã£ã. 3)ä»æ¹,èžçºèšèžçºéãåºã«ããŠæ±ããèžçºæ£é en,tn ã®çµæã¯Iæéã12.04mm/day,â
¡æéã11.62mm/day,â
¢æéã8.42mm/day,ã®çµæãšãªã,èšåšèžçºéãåºã«ããŠç®å®ããæ¹ã,3æåãšãè¥å¹²,en,tnãå®æž¬æ°Žåæ¯ã®çµæããå€ã倧ãã. ããã,ãããã®å·®ã¯æ¥µããŠå°ãã. 4)åŸã£ãŠ,æ¬å°åã®ããã«äœå¹³å°æ°Žç°å°åž¯ã®æ¶è²»æ°Žéã¯en,tnã«ãããã®ã§ãã,åŸã£ãŠG2-G1â0â¿Sâ0ãšã¿ãªãããã®ãšèãããã. 5)以äžãã,æ¬å°åã«ãããæ¶è²»æ°Žéã¯,en,tnçšåºŠã®ãã®ã§ãããªãã,ããããæ°Žéãšææ°Žéã®äž¡è
ã極ããŠå€ãããšã¯æ³šç®ãã¹ãã§,ããããææ°Žéãäžé©æ£åããããšãæãŸãã. 6)次ã«æ¬å°åã®çšæ°Žã®å埩å©çšéãæ€èšããŠã¿ããšãã,å¹³åçã«ã¿ãŠ,ããã5ïœ6mm/dayã®æ°Žéãå埩å©çšãããŠããããšãæãããšãªã£ã. ãããã«,æ¬è«æã¯æå37幎,èè
ã京倧åšè·äžã«è¡ãªã£ãå·šæ€æ± å¹²æå°,ããããææ°Žã®å®æ
調æ»ç 究ã®äžéšã§ããããšãä»èšã,埡æŽå©ããã ããå·šæ€æ± åå°æ¹è¯åºã®é¢ä¿åäœã«è¬æãè¡šãã次第ã§ãã
A Study to Increase the Sensitivity of an Observation Pipe to Rapid Changes of Water-Table
åå£äžã®æ°Žåç°å¢ãæé©ãªæ¡ä»¶ã«ä¿æããæ¹æ³ãšããŠ,ãããã¯é©æ£æµžééãäžããæ¹æ³ãšããŠå°äžæ°Žäœãã³ã³ãããŒã«ããææ³ãæçšãšãããŠãã. äžæ¹å°äžæ°Žäœã枬å®ããæ¹æ³ãšããŠã¯ãã€ããå°äžã«æ蟌ãã§ãã€ãå
æ°Žäœã枬å®ããã®ãäžè¬çã§ããã,ãã®é,å°äžæ°Žäœã®å€åã«å¯Ÿå¿ãããã€ãå
æ°Žäœã®Time lagãã§ããéãå°ããããå¿
èŠãããã€ãã®åšå²ã«ãã£ã«ã¿ãŒããŸãã®ãæ®éã§ãã. ããã,ãã®å Žåã®ãã€ããšãã£ã«ã¿ãŒã®å€§ããã«ãã£ãŠãããªãæ床ã瀺ããã¯åŸæ¥ããŸãæ確ã«ãããŠããªã. ããã§æ¬è«æã§ã¯ãã®ç¹ãæ確ã«ããããã«ãã€ããšãã£ã«ã¿ãŒã®çµåããã«ãã£ãŠæãæ床ããæ°Žäœãå¿çããé¢ä¿ãæããã«ããããã®å®èšŒçç 究ãè¡ãªã£ãçµæã«ã€ããŠå ±åããŠãã. ãããã®çµæã«ã€ããŠèŠçŽããã°æ¬¡ã®éãã§ãã. 1)䜿çšãããã£ã«ã¿ãŒã®ç²åŸããããã°Fig.4ããæå¹åééãçŽã¡ã«æãããšãªã. 2)ãã£ã«ã¿ãŒã®ç²åŸã2mm䌌äžã®å Žåã«ã¯,ééçãšæå¹åéçãšã®éã«ã¯ããŸã倧ããªå·®éã¯ã¿ãããªã. 3)å°äžæ°Žäœæž¬å®çšãã€ãã®åŸãšãã£ã«ã¿ãŒã®æå¹åéããããã°R=râ1/p-1ããçŽã¡ã«æãå¿çã®ãããã£ã«ã¿ãŒã®ååŸãããã. 4)æé©åŸæ¯R/rã®æ¡ä»¶ãšããã§ãªãå Žåã®2ã€ã®æ¡ä»¶ãäžã,å®éã®åå Žã«ãããŠãããã®æ¯èŒå®éšãè¡ãªã£ãçµæ,çè«çã«å°ããæé©åŸæ¯ã®åŠ¥åœæ§ãå®èšŒããã. 5)以äžã«ãã£ãŠå°äžæ°Žäœã®å€åã«å¯ŸããŠ,æãå¿çã®è¯ãå°äžæ°Žäœæž¬å®çšãã€ãã®èšçœ®æ¹æ³ãæãããšãªã£ã
Properties of soil layer of the consolidated paddy field
In case of readjustment and regrouping of paddy fields after land consolidation project, different characters of the original fields should have some influence on the characteristics of the expanded field, especially on the variation of soil condition. Then, two of 50a (100Ã50m) paddy fields, each of which was consolidated from five of 10a (20Ã50m) fields,were investigated about the distribution of water content and cone index of the field. The water content of surface soil layer was measured after drainage of residual water at 15 (3 x 5) intersecting points of cross lines at equal intervals. And data of cone index were measured at the same places as in the case of water content, and averaged every 10cm depth (0ïœ10cm, 10ïœ20cm, 20ïœ30cm, respectively). The results of these investigations are as follows. i) In the surface soil layer (0ïœ10cm), where homogeneity of soil condition has been progressed, the measured data are affected rather by the characteristics of the expanded field such as variation of mulching and surface elevation, than by the characteristics of the original field. ii) In the subsurface soil layer of 10ïœ20cm and 20ïœ30cm depth, owing to differences of characters of each original paddy field, there are no homogeneity of cone index. These show the necessity of considering homogeneity of field conditions, especially of the soil, for the purpose of apposite estimation of trafficability of farm machinery and efficient usage of it on the expanded paddy field, on the land consolidation work
Subsoil Characteristics of the Consolidated Paddy Field by Bulldozer : Studies on the Land Consolidation of Sloped Clayey Paddy Field(II)
In case of consolidating clayey paddy field in the sloped area, there usually a great deal of the earth work is requied âãcutting and banking and the soil is highly moistened. To clarify the effect of such working conditions on the properties of the field after consolidation, investigations are made of the number of times of pass of bulldozer, soil moisture and density, corn index, and settlement of the field. The results that obtained are : a) There are considerable variations of the properties of field soil in one lot after consolidation. b) The soil moisture conditions at the earth work so significantly affect the properties of soil as to show such variable conditions. c) Non-uniformity of soil density and bearing characteristic, and large pores in subsoil cause heterogenious settlement of the field, and partial subsidence. These results especially show the significant importance of soil moisture control at the earth work
A Basic Planning of Land Utilization and Development in Shoei Regions : Studies on the Land Utilization and Readjustment for the Re-development of a Rural Regions[I]
The planning of land utilization and readjustment including living-circumstances in the rural regions has become a very important problem. Here we set up the basic planning of land utilization and development in 1985 in Shoei District which covers five towns belonging to Katsuta and Aida countries. In this case, the influences that may be brought by the Chugoku traversing highway are especially taken into consideration. The aims are as follows: 1) About 2, 700 ha of rich flat land are allocated to paddy fields. 2) It is necessary to develop a hillock plateau and make it into a chief producing district of fruits. 3) To promote animal husbandry, it is necessary to develop adjacent slope combining with valley bottom paddy fields. 4) To advance the economical stability and progress of the inhabitants, we aim to attract factories according to the land utilization planning. 5) In consequence of these enforcement, the agricultural population in this district decrease to about 55% or 41% of that of the present
Fundamental Investigation and Study on the Development and Conservation of Agricultural Land in Mongolia I. : Particularly on Physical and Chemical Properties of Soils in Zunhara
çç£æ¥ãåœå®¶çµæžã®äž»åãå ããã¢ã³ãŽã«ã«ãããŠ,ç£æ¥æ§é å€é©ãžã®åªã«ãšçžãŸã£ãŠ,蟲ç£æ¥ã®æ¯çã¯æ¬¡ç¬¬ã«å¢å ãã€ã€ãã. æ¥èåŠè¡äº€æµã®é²å±ã«ãã,ã¢ã³ãŽã«ã«ãããçŸå°èª¿æ»ãè¡ãªãæ©äŒãåŸãçè
ã¯,也ç¥æ°åäžã§ã®å®å®ãã蟲æ¥çç£åºç€ã¥ããã®ããã®åççãªã«ã³ã¬ã€çµç¹,é æãã蟲å°ã®é¢šé£ãæ°Žé£ã«å¯Ÿããä¿å
šç,ç 究ãã¹ãå€ãã®èª²é¡ãèŠãåºãã. æ¬å ±åã¯ãŸããã®åºç€ãšããŠ,蟲æ¥çç£ã®åºç€ã§ããåã®ç©çã»ååŠè«žç¹æ§ã«ã€ããŠå®éšã»æ€èšãå ãããã®ã§ãã,ãã®çµæã¯ä»¥äžã®ããšãèŠçŽããã. è©Šæåã¯,æªèäœåãšèäœéå§åŸ2,6,10幎ãçµéããçã«ãããŠ,åå°ç¹äžäž2å±€ããæ¡åãã. ãŸãååŠæ§ã«ã€ããŠã¯,åå£çææ¯æã¯ã¬ã¹(ç«å±±ç°é¢šç©å)ã§,調æ»å°ç¹ãã¹ãŠåäžãšèãããã. èäœé姶åŸã¯,å
šççŽ å«éã®æžå°,C/Næ¯ã®äœäž,pHã®äœäžãªã©2,3ã®æ§è³ªã«èäœã®åœ±é¿ãè¥å¹²ã¿ãããã,ååŠåæçµæã¯äžçšåºŠã®å€ã瀺ãäžã§ããããšã瀺ãã. 次ã«ç©çæ§ã«ã€ããŠã¯,äžçžååžçµæããæ¬åå£ã¯èªç¶ç¶æ
ã«ãããŠããªãå¯ãªåå£æ§é ã圢æããŠãã,èäœã«ããçµå¹Žçã«å£ç²æ§é ãçºéãããšæãã,ããã¯pFïœæ°Žåæ²ç·ã§äœpFåã§ã®ä¿æ°Žæ§ãå¢å€§ããåŸåãããããããã. ãã®çµæããã¿ããš,æ¥æ¬ã«ãããæ²,措ç©åå£ã®çå°ã«é¡äŒŒããæ§è³ªãšæããã. 次ã«ç²åŸååžãã,ã»ãŒSiCã«åé¡ãããã埮现ãªæ§é ã§ããã,颚也ã«ããã³ã³ã·ã¹ãã³ã·ãŒå€ã®äœäžã¯éåžžã«å°ãã,ééšéã極端ã«å°ãªãæ°è±¡æ¡ä»¶äžã§,ååãªé¢šä¹Ÿäœçšãåããçµæãšèãããã. ãã®ããã«,埮现ã§åŒ·åºŠã®ä¹Ÿç¥äœçšãåããåå£ã¯,æ°Žé£ã颚é£ã®åœ±é¿ã倧ããåãããšæšæž¬ãã,èæ°Žé£æ§ã«ã€ããŠã¯ããã«ãã³ã®äŸµé£ç枬å®çµæãã,匷床ã®åé£æ§åå£ã§ããããšã瀺ããã. å®éã®ã«ã³ã¬ã€èšç»ã«ã€ããŠã¯,ä»åŸèžçºæ£éãåå£æ§é ã®é¢ããããã«æ€èšããå¿
èŠãããã
On the percolation water model through down from the paddy fields(II) : On the modelization of percolation down from a unit of a field lot of paddy field and the measurable quantities
In this paper, supposing that the following equation is concluded, it induces the model of a field lot as a unit in the case of thinking about percolation on large project, and moreover we discuss about some quantities measured in practice. âx/âïŒR2/1 âïœ/âH)ïŒây/â(R2/1 âïœ/â)ïŒR1/1ïŒH0-H)=0 The results in this paper are summarized as follows. l) In treatment of percolation in the paddy field on large project, the unit is one field lot surrounded with drainage canal. Regarding the one field lot as a unit, physical quantities concerned are q , q1, q2, S1 and S2. We induced the relation among them. 2) Thinking" about the vertical section crossing drainage canal in the two dimension, the apparent model indicating" the motion of percolation water in that vertical section is shown in the Fig. 2, and moreover it is transformed to equivalent model shown in the Fig. 4. Parameters indicating the characters of this model are R and RH, or R' and RH'. 3) This model is induced from the start-point of equation (1) concluded in the macro soil model. And then, in the two layer geometrical model L/D=5, D/d=4, as the result of comparing Darcy's dimensional solution with this model in the case of k2/k1=1 and k2/kl=20, both are not very good consistent in the case of k2/k1=1, but are fairly good consistent in the case of k2/k1 = 20. From this result, it may be considered that the propriety of applicable extent (k2/k1 > 10) for the macro model could be proved. 4) The quantities measured in practice are q , S . S1 and S2, and parameters included in the equations should be calculated back from these quantities
Soil Layer Change in Experimental Field Resulting from the Drying after Land Drainage : Studies on the Soil Improvement and Reasonable Water Requirement for Desalinization in Kasaoka Bay Polder(I)
ç¬ å²¡æ¹Ÿå¹²æå°ã«ãããŠ,å¡©ã«åŒ±ãçäœç©ã®æ£åžžçè²ãä¿èšŒãåŸãåå±€ãžãšæ¹åããããã®æéã®çå®ã«åœãã,å
ã1977幎å€ã®å¹²éžåŸããã®åå±€å€åã®å®æ
ã,è©Šéšåå Žã®No.10åºã«ããã調æ»çµæããæ€èšŒãã.ãã®çµæãèŠçŽãããš,以äžã®éãã§ãã. 1,åå£ã®ç©çççæåã«é¢ãã調æ»ã®çµæ,å«æ°Žæ¯ãšä¹Ÿç¥å¯åºŠããã¿ãå¹²éžåŸã®ä¹Ÿåååã³é€å¡©ã¯,åæã®æ¥éãªé²è¡ãš1982幎é ããã®åæ»ãšã«ç¹åŸŽä»ãããã. 2.ãã®åæ»ãæç Žããã«ã¯åå£ç©çæ§ã®æ¹è¯ãå¿
é ã®æ¡ä»¶ã§ãã,ãããç®çãšããŠæ··å
¥ãããç³èã®å¹æã¯,ä¿æ°Žæ§ã®æž¬å®çµæããå®èšŒãããããã«,æ··å
¥åå±€ã«ãããŠå€§ããçºæ®ãããåŸåã«ããããšãæãããšãªã£ã. 3.ååŠççæåã«é¢ãã調æ»ã®çµæ,ç³èã®æ··å
¥ã«ããè¡šå±€éšã®äº€ææ§NaçŸåçã倧ããäœäžã,åå£ã®ç©çæ§ã®æ¹åãžãšé£åããç¶æ³ãæçã«èªã¿åãã.ããã,深局éšã®æ¹è¯ãéåžžã«å°é£ã§ããæ§çžããŸãé¡èã«ç€ºããã. 4.ææž ã®ææ°Žæ©èœã¯,åå£ã®ç©ççæ§è³ªã«æ¯é
ããå€åããã,é©åãªåå±€æ¹è¯ãžã®å¯Ÿå¿ã«ããå¥å
šã«ç¶æãããããšãåãã£ã. 5.1985幎åœåã®æç¹ã§ã¯,ç³èã®æ··å
¥ã«ããå£åããåå£ã®ç©çæ§ãæ¹åã,åæ»ããé€å¡©ãé²å±ããã察å¿ã¯æ¥µããŠæåã§ããäºãæããã«ããã.ä»åŸã¯,éãšæ·±ãã«é¢ããåççãªæ±ºå®æ³ã«åºã¥ãæ··å
¥ãããç³èã®å¹æã«ã€ããŠã®è¿œè·¡èª¿æ»ãšè§£æãžãšé²ãäºå®ã§ãã