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1.
Yoshikazu Takaya Kazutake Kyuma Keizaburo Kawaguchi 《Soil Science and Plant Nutrition》2013,59(3):209-223
In order to characterize the rice cultivation in the Mediterranean countries, climate and physiography of rice growing areas in Italy, Spain, and Portugal were studied. In northern Italy rice is extensively cultivated on terraces and fluvial plains of the Po and its tributaries, making use of the supply of water from Alpine glaciers in addition to the relatively abundant rainfalls of the area. In the Iberian peninsula summer climate is so dry that rice is cultivable only where the ratio of catchment area to rice land area is sufficiently large, thus rice lands are practically limited to the floodplains and deltas of the big rivers, such as the Sado and the Tejo in Portugal and the Guadalquivir and the Ebro in Spain. In order to characterize the rice cultivation in the Mediterranean countries, climate and physiography of rice growing areas in Italy, Spain, and Portugal were studied. In northern Italy rice is extensively cultivated on terraces and fluvial plains of the Po and its tributaries, making use of the supply of water from Alpine glaciers in addition to the relatively abundant rainfalls of the area. In the Iberian peninsula summer climate is so dry that rice is cultivable only where the ratio of catchment area to rice land area is sufficiently large, thus rice lands are practically limited to the floodplains and deltas of the big rivers, such as the Sado and the Tejo in Portugal and the Guadalquivir and the Ebro in Spain. 相似文献
2.
Hideaki Hirai Katsutoshi Sakurai Kazutake Kyuma 《Soil Science and Plant Nutrition》2013,59(3):497-507
Abstract Properties of sesquioxides, clay mineralogical composition, and charge characteristics of Brown Forest soils developed under beech forests in the Kinki (Ohdaigahara) and the Tohoku District (Hakkoda) were studied with special reference to their pedogenetic processes. The Brown Forest soils in the Kinki District were characterized by the translocation of free Al, formation of Al and/or Fe-humus complexes throughout the profile, and the predominance of 2:1: 1-2:1 intergrade minerals in the subsurface horizons, whereas those in the Tohoku District were characterized by the formation of allophane and no remarkable translocation of free Al oxides. This difference in the pedogenetic processes under the same vegetation was reflected on the amounts of Al released from primary minerals in relation to the amounts of organic matter accumulated. Major distinctive characteristics included the values of the Alp/Alo, the Fep/Feo, the Alo/Ald ratios, the Sio content, and the STPT-ZPC and pH(H2O) values. Among these the values of the Alo/Ald ratio and/or the Sio content were found to be suitable indices for the differentiation of Brown Forest soils from Andisols in Japan In addition to the criteria used to define andic soil properties. 相似文献
3.
Kazutake Kyuma Tomoo Hattori Keizaburo Kawaguchi 《Soil Science and Plant Nutrition》2013,59(3):225-240
In Italy paddy aolls have a broad varfability with respect to region and age of the parent material. The regional characteristics, however, predominate over the age relations, i.e., the Po delta soils have higher potentialities than the youngest of those in the middle reaches of the Po. Among soils of the middle reaches the older the parent material, the more depleted the bases. Some of the better drained terrace soils have the morphology of “aquorizem.” Spanish paddy soils along the Mediterranean coast are all alike, having an alkaline reaction due to the presence of free lime, and SiCL to SiC textures. Morphologically there are two types of paddy soils, one having gleyed subsoils due to groundwater influence, and the other having brown subsoils below strongly gleyed aurface soils under aubmergence. Portugese paddy soils are generally similar to Spanish soils both in mode of occurrence and In nature, except for neutral to slightly acidic reaction and absence of free lime in the former. The general soil potentiality aa judged from chemical and mineralogical atudies is in the order of Spanish>Portugese>Italian paddy aoils. 相似文献
4.
The relationship between the charge characteristics and the dispersibility of soils from reclaimed land (highly dispersive) and adjacent forest area (physically stable) was investigated. To evaluate the amount of soil charges quantitatively, the measurement based on cation and anion adsorption (ion adsorption method) was attempted in two ways, where special attention was paid to the solution concentration. In the conventional ion adsorption method, the treatments with concentrated solutions (1 mol L-1) were included in the process. In the modified method, soils were treated with dilute solutions (5 mmol L-1), in taking account of the soil solution concentration in humid temperate regions. The amount of charges derived from the modified method was smaller than that from the conventional one, especially in the high pH zone. In a preliminary experiment, the extraction of polyvalent cations from soils was found to be significantly affected by the salt concentration. Thus, the use of solutions with an excessively high concentration was considered to result in an error in the estimation of the active charges in soils which would contribute to the dispersion behavior in the field. The applicability of the modified method for analyzing the dispersion behavior of soils was evaluated by relating the dispersibility of silts and clays at different pHs with the charge characteristics determined under the same ionic strength. The dispersion ratio of silts of the reclaimed land reached maximum values at pH 5.5, above which the ratio decreased, whereas the ratio of clays began to increase in the pH range above 6. The dispersion ratio of silts of the forest area increased in the pH range above 6, whereas that of clays remained constant at a low level in all the pH ranges below 7. The changes in the dispersibility of silt plus clay fractions corresponded to total charge characteristics determined by the modified method. Thus, the evaluation of soil charges by the modified ion adsorption method was considered to be effective to predict soil dispersibility under field conditions, indicating that it could replace electrokinetic analyses such as electrophoresis in studies on the dispersion/flocculation behavior of soils. 相似文献
5.
Effect of Addition of Al Hydroxides on Changes in Dispersibility and Charge Characteristics of Soils
Katsuhiko Itami Yasuo Kitagawa Kazutake Kyuma Takashi Kosaki 《Soil Science and Plant Nutrition》2013,59(3):627-635
Using a soil from a newly reclaimed area where high dispersibility of fine particles had led to poor physical properties in the field, changes in dispersibility and charge characteristics after artificial precipitation of Al hydroxides onto the soil were investigated. Al hydroxides were precipitated by neutralization with NaOH of an acidic A1C13 solution in which the soil samples were placed. When the titration rates were changed, no significant differences in dispersibility were observed in the resultant soils. In the systems with the addition of 2 g kg-1 or less of A1(OH)3, dispersion ratios of clays were almost identical with those of blank samples although the specific surface areas were reduced. In the systems with 5 g kg-1 or more of A1(OH)3, considerable effects of Al hydroxides on reduction of clay dispersibility were recognized (e.g. 10 g kg-1 addition yielded less than one-third of the original ratio of the clay dispersion). A slightly larger decrease in dispersion was observed by the addition of 15 g kg-1 or more. As the amount of added Al increased, the amount of negative charges of the soil decreased while that of positive charges increased. The charge characteristics of the system with the addition of 20 g kg-1 of A1(OH)3 were closer to those of the adjacent forest soil which was characterized by a very low dispersibility. It was inferred that added Al hydroxides polymerized to form Al polycation species that were not readily exchangeable, neutralizing negative charges of clays, and acting as interparticle bonding between the clays. On the other hand, forest soils were considered to have acquired a physical stability against the dispersion of fine particles as free Al oxides had been accumulated in the process of natural weathering. It was concluded that charge characteristics primarily determined the dispersion and flocculation behavior of soils and that Al hydroxides were important modifiers of charge characteristics of soils. 相似文献
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7.
Abstract Morphological and chemical properties of brown forest soils and podzolic soils developed on paleozoic shale under beech and/or cryptomeria have been studied with special reference to the eluviation-illuviation characteristics of Fe and Al. Mobilization of Al was observed even in brown forest soils and its pattern was similar to that in podzolic soils. Its intensity was higher in the brown forest soils developed on the ridge under cryptomeria than in those on the slope under beech. Hence, podzolization is considered to be one of the genetic processes involved in the brown forest soils in question. Furthermore, the value of (Fep+Alp)/clay that is employed to define a podzolic B or spodic horizon indicated the presence of a podzolic B horizon even in the brown forest soils studied, while no spodic horizon was found even in the podzolic soils with a clearly recognizable albic horizon. Moreover, the examination of the degree of podzolization showed that the brown forest soils almost corresponded to Ochreous brown earths. 相似文献
8.
Hideaki Hirai Kazuhiro Yoshikawa Katsutoshi Sakurai Kazutake Kyuma 《Soil Science and Plant Nutrition》2013,59(3):509-519
Abstract Properties of sesquioxides, clay mineralogical composition, and charge characteristics of the soils developed under broad-leaved evergreen forests in Okinawa Prefecture (subtropical climate) and the Kinki District (warm temperate climate) were studied with special reference to their pedogenetic processes in order to reexamine the corresponding parameters of Brown Forest soils and related soils in Japan. The soils in Okinawa Prefecture were characterized by a higher degree of weathering as compared to the soils in the Kinki District. Major differences involved the values of the Fed/Fet ratio for the soil samples throughout the profile, and those of the ratios of (Fed-Feo)/Fet, CEC/clay, and (Feo + Alo)/ clay and the content of CaO plus Na2O for the B horizon. The soils in the Kinki District did not show andic soil properties, nor Al translocation in the profile and, both of which were characteristic of Brown Forest soils developed under cool temperate climatic conditions at high altitudes in the same District. The difference in the degree of weathering were reflected on the charge characteristics at the very surface of the soils, i.e., the surface of the particles of the soils in Okinawa Prefecture exhibited a lower reactivity as compared with those of the soils in the Kinki District. 相似文献
9.
Kazutake Kyuma 《Soil Science and Plant Nutrition》2013,59(4):155-167
The present paper deals with a classification of the climate of Japan for setting up climatic regions as a basis of classification of alluvial soils. By definition alluvial soils are those which have undergone little change under the influences of pedogenetlc processes. Accordingly the ordinary classificatory method based on the profile morphology does not work effectively for these soils. The morphological features, if any at all, do not properly reflect the influence, especially, of climate. 相似文献