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1.
For the past ten years much work has been carried out on clay minerals of volcanic ash soils. Most investigators have reported that allophane is dominant among clay minerals of volcanic ash soils and crystallizes to halloysite or meta-halloysite with the advance of weathering (1–8). On the other hand, UCHIYAMA, MASUI and ONIKURA (1960) found that montmorillonite predominates in the clay fraction of volcanic ash soil in Kawatabi (9). Furthermore, MASUI, SHOJI and UCHIYAMA (1966) showed that the major crystalline clay minerals of volcanic ash soils in the Tohoku district are montmorillonite, vermiculite, intergradient montmorillonite-vermiculite and chlorite (10). They also showed that these minerals increase with the advance of weathering and that kaolin minerals are minor constituents.  相似文献   

2.
A characteristic gel-like substance has been noticed around weathered pumice grains in the pumice beds of Kanuma near Utsunomiya and of Kitakami, Iwate prefecture. This substance was first studied by SHIOIRI (6) in 1934, and reported as allophane according to its chemical composition, refractive index, and dye-adsorbing nature similar to the colloid of volcanic ash soils of the Onji-type. Recently, KUWANO and MATSUI (5) remarked that the colloidal film in the Kanuma and Imaichi pumice beds diffracted x-rays at about 8 and 33 Å, and they presumed that this substance might be an early transitional material from allophane to some crystalline clay minerals. KANNO (2) and KANNO et al. (3) examined this gel-like substance from Imaichi and Kitakami districts precisely by the x-ray diffraction, differential thermal, infrared spectroscopical, electron microscopical, and chemical methods, and they concluded that the substance was a mixture of poorly crystallized montmorillonite, allophane in various weathering stages, and free sesquioxide, although there was no positive evidence of montmorillonite. YOSHINAGA and AOMINE (7) noticed that the properties of imogolite designated by themselves bore a striking likeness to those of the gel-like substance reported by KANNO et al. (3), and they considered that both substances were essentially of the same kind irrespective of occurrence.  相似文献   

3.
Phosphorus in soils is found to be present in organic combinations, inorganic form or in adsorted form on clay complex. Different forms of soil phosphorus have different solubilities and consequent availability in soils. A knowledge about the content and types of soil phosphorus enables one to understand the organic behaviour and predict the response of added phosphatic material to crops (Parker 1953). The form in which phosphorus is present in soil is directly related to pH and CaCO3 in the soil as well as the intensity of the development of the soil. Williams (1950) has found that in calcareous soils of South Australja most of the phosphorus was in combination with calcium, whereas in acid soils it forms compounds with alumina and iron. Hibbard (1931) concluded that in alkaline and calcareous soils, phosphorus exists mostly in the form of hydroxyapatite, chloroapatite, and the like. Kanwar and Grewal (1959) studied fractionation of phosphorus in Punjab soils and reported that differences in the nature and amounts of the phosphorus present in acid and alkaline soils of the State explain the causes of different phosphatic fertilizer responses to the crops. A similar report has been given by Goel and Agarwal (1959) who studied the fractionation of phosphorus in Kanpur soils and concluded that the mature soils are rich in iron and aluminium bound phosphorus and respond better to phosphatic fertilizer than the immature soils rich in Ca2+ and Mg2+ bound phosphorus. Chai Moo Cnoo and Caldwell (1959) reported that Fe3+ and Al3+ bound phosphorus was abundant in acid soils while Ca2+ and Mg2+ bound phosphorus content in alkaline soils, and organic phosphorus agreed, in general, with the content of organic matter, with some deviations.  相似文献   

4.
The soils of Rajasthan vary from desert sand to heavy clay with all intermediate stages like sandy loam, loam and clay loam. The last two textural groups are more prevalant on the eastern, northeastern and southeastern part of the Aravallies which run almost in the middle of the State from southeast to northeast. The latter groups of soils have more potential from the point of agricultural development in the State. These soils are widely termed as alluvial soils which is a general term to indicate the nontaxonomic group of soils that have parent material of alluvial origin, Riecken 17, Kelloog 8 has referred to the soils developed from the alluvium as classified under variety of world soil groups. In our country many of the alluvial soils have not yet been studied from the soil genesis point of view as a measure to classify the soils under taxonomic groups. Ray Chawdhary and Mukerji 15, concluded that the alluvial soil groups of our country are ill defined and the classification of these soils need more study. Basu 3 was able to distinguish the genetic characteristics of the soils of Deccan. Agrawal and Mukherji 1) established that distinct genetic soil types have come into expression under Gangetic alluvium. Agarwal 2 has concluded about the three types of soils in the toposequence with precipitated calcium throughout, zone of calcium accumulation in the bottom of the profile and soils free of calcium, and suggests that the soils of Gangetic plain be called as derived from alluvium. A process of reclassifying the alluvial soil series into taxonomic groups is a common trend in the United States since the last two decades.  相似文献   

5.
To explain why soils rich in variable charge materials often lack 1 M KCI-extractable Al ions, I proposed a mechanism, an “induced hydrolysis” of exchangeable Al ions in the presence of variable charge materials at high salt concentrations.

I extracted exchangeable Al from mixtures of a montmorillonite saturated with Al and a synthetic goethite using a 1 M KCI solution. The amount of the extractable Al (per unit weight of the montmorillonite) decreased with increasing proportion of the goethite in the mixtures. I interpreted this experimental result as supporting the proposed mechanism, i.e., H+ released in the hydrolysis of Al is adsorbed on the goethite in a concentrated KCI solution and this removal of H+ induces further hydrolysis, resulting in the polymerization or precipitation of Al as hydroxides.

I calculated the amount of monomeric, therefore extractable, Al as a function of the goethite content in the 1 M KCI-montmorillonite-goethite mixtures. The calculated amounts agreed well with the experimentally determined ones in the whole range of goethite content examined.  相似文献   

6.
Barley plants were grown hydroponically at two levels of K (3.0 and 30 mm) and Fe (1.0 and 10 μm) in the presence of excess Mn (25 μm) for 14 d in a phytotron. Plants grown under adequate K level (3.0 mm) were characterized by brown spots on old leaves, desiccation of old leaves, interveinal chlorosis on young leaves, browning of roots, and release of phytosiderophores (PS) from roots. These symptoms were more pronounced in the plants grown under suboptimal Fe level (1.0 p,M) than in the plants grown under adequate Fe level (10 μm). Plants grown in 10 μm Fe with additional K (30 mm) produced a larger amount of dry matter and released less PS than the plants grown under adequate K level (3.0 mm), and did not show leaf injury symptoms and root browning. On the other hand, the additional K supply in the presence of 1.0 μM Fe decreased the severity of brown spots, prevented leaf desiccation, and increased the leaf chlorophyll content, which was not sufficient for the regreening of chlorotic leaves. These results suggested that the additional K alleviated the symptoms of Mn toxicity depending on the Fe concentration in the nutrient solution. The concentration (per g dry matter) and accumulation (per plant) of Mn in shoots and roots of plants grown in 10 μm Fe and 30 mm K were much lower than those of the plants grown in 10 μm Fe and 3.0 mm K, indicating that additional K repressed the absorption of Mn. The concentration and accumulation of Fe in the shoots and roots of the plants grown in 10 μm Fe and 30 mm K were higher than those of the plants grown in 10 μm Fe and 3.0 mm K, indicating that the additional K increased the absorption of Fe under excess Mn level in the nutrient solution. The release of PS, chlorophyll content, and shoot Fe concentration were closely correlated.  相似文献   

7.
A greenhouse experiment was conducted at Land Resources Research Institute, NARC, Islamabad to examine the impact of humic substances (HSs) coating on potassium fertilizers use efficiency. Tomato variety “Rio Grande” was used. The treatments applied were T1= Control (N, P at 250 and100?mg kg?1 respectively), T2?=?N, P?+?K at 200?mg kg?1 as SOP, T3?=?N, P?+?K at 200?mg kg?1 as NPK blend, T4?=?N, P?+?K at 200?mg kg?1 HSs coated SOP) and T5?=?N, P?+?K at 200?mg kg?1 HSs coated NPK blend. Results indicated a positive impact of sole and HSs coated products on agronomic traits, nutrient concentration, fruit quality traits, flower number, fruit umber, fruit weight, chlorophyll contents, fresh and dry biomass, tissue water contents, diameter and fruit mineral composition. The response of afore said traits to applied treatment varied.  相似文献   

8.
Abstract

Microbial metabolism in reduction process of waterlogged paddy soils has been studied by Takai, Koyama, and Kamura (1, 2, 3, 4, 5, 6), Koyama (7, 8, 9, 10, 11, 12), and others. The results indicated that microbial metabolism in waterlogged soils takes place according to the following steps: (1) In the early stage of the incubation period, dissolved O2, is consumed and the redox potential drops rapidly. (2) NO2? and NO2? are reduced to N2. (3) Mn4+ is reduced to Mn2+. (4) Fe3+ is reduced to Fe2+. (5) SO4 2? is reduced to S2?. (6) H2 and CH4 are produced. Takai and Chiang (13) reported that NH4+ and PO4 3+ in waterlogged paddy soils increase with the incubation period. Chiang and Takai (14) indicated that carbohydrates in the soil solutions almost remain constant throughout the incubation period, however, organic acids change similarly to those reported previously (5, 6).  相似文献   

9.
In the past several years, the occurrence of vermiculite-type clay minerals and the problem of the formation of Al-interlayers have attracted the intensive attention of soil clay mineralogists. A number of papers have appeared in Japan, in Which the identification data of the vermiculite-type minerals with stable 14 Å spacing were given. (Matsui 1959, 1960; Kanno 1961b, Kato 1961, 1962a, 1962b; Egawa 1963).  相似文献   

10.
Investigations on the extraction and determination of organic acids in flooded soil have been reported by TAKAI (1) and TAKIJIMA (2). TAKAI applied water to extract acids from soil and determined them by BULLEN's method (3). However, TAKIJIMA reported that organic acid could not be completely extracted by TAKAI's procedure, especially in soil with a high organic matter content such as muck and peaty soils, and proposed an extraction procedure with 0.5 N sulfuric acid. He also discussed the absorption of acids by soil.  相似文献   

11.
Nonexchangeable potassium (K-ne), i.e. 1 M NH4OAc-nonexchangeable K, often contributes significantly to plant nutrition. However conventional extraction methods often extract much more K-ne than plants even after intensive cropping, suggesting the difficulty in evaluating the amount of readily available soil K-ne. In this study, we used a milder extraction method (0.01 M HCl method) to examine its applicability to evaluate the amount of readily available K-ne in soil. In the first experiment, the concentration of K-ne in twenty surface soils sampled from agricultural fields in Japan and K-bearing minerals was determined by the 0.01 M HCl method, i.e. sequential extraction with 0.01 M HCl over a period of 10 d after removal of exchangeable K, and by conventional methods. The average percentage of the soil K-ne extracted by the 0.01 M HCl method amounted to 0.66% of the total K amount, and was much lower than that by a single extraction with 1 M HNO3 (2.0%) or with 0.2 M sodium tetraphenylboron for 2 d (22%). In the second experiment, the amount of K-ne removed by chemical extractions was compared with that of K-ne removed by maize plants grown for 29 d in five of the above soils. The amount of the K-ne evaluated by the 0.01 M HCl method gave the highest correlation (p < 0.05) with that of the K-ne utilized by plants among the extraction methods applied. The amount of soil K-ne extracted by the 0.01 M Hel method could therefore become a suitable index of the amount of readily available K-ne in soil. Extraction of K-ne in soils after maize planting further indicated that plants had removed K-ne more intensively than the 0.01 < HCl method probably only from the rhizosphere, although a high correlation was observed between the amount of K-ne removed by the 0.01 M Hel method and that by plants. This implies that the estimation of the amount of K-ne utilized by plants requires not only soil chemical analysis but also the evaluation of the percentage of the soil volume where the plant-induced release of K-ne actually occurs.  相似文献   

12.
The central districts of Japan are mountainous areas rising to 3,000 metres which are predominantly covered with forest vegetation. A comprehensive and systematic classification of the soils in this region has not yet been made, but the following soil types have been reported to occur: - 1. 1. Brown forest soils, podzolic soils, black soils and red soils. [Described by OHMASA (14)]

2. 2. Alpine grassland soils and alpine meadow soils. [Described by KUMADA et al. (9)]

3. 3. A series of randzina-like soils with a very restricted distribution. These are derived mainly from limestone and show various degrees of maturity. [Described by KUMADA et al. (8)]

4. 4. Red-yellow soils. These sometimes show a close resemblance to OHMASA's red soils and are found on diluvial plateaux and hills. [Described by KANNO (1)]

5. 5. Paddy soils.

  相似文献   

13.
It is well known that methyl mercaptan is porduced by the microbiological decomposition of methionine1),2),3). According to Kondo 4) and Onitake 1)not only hydrogen sulfide, but also methyl mercaptan were produced from cystine by E. coli and Proteus vulgaris in the medium containing one of glucose, lactose, sucrose, glycerin or histidine. Moreover, Onitake 1) found that methyl mercaptan was produced by the action of E. coli in the medium containing hydrogen sulfide and a trace of ethyl alcohol, and that evolution of methyl mercaptan began only 5 minutes after the start of experiment in the medium containing methionine, but it began after 12hrs in the medium containing 1-cystine and glucose. According to Birkinshaw, Findlay and Webb5) methyl mercaptan was found in the medium containing glucose, sulfate and other mineral salts, inoculated by Schizophyllum commune. In the same cultural condition as given above, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide were detected by Challenger and Chartons 5) from the data presented above, in addition to microbiological formation of methyl mercaptan from methionine, the possibility cannot be excluded of methyl mercaptan formation by microbes from cystine, sulfate or hydrogen sulfide in the medium containing one of organic compounds such as sugars, glycerin, histidine and ethyl alcohol, etc.  相似文献   

14.
Blast disease is one of the biggest diseases of rice plant in Japan. For example, in 1953, the total area of damage by blast disease was about 160 × 104 hectare and the decreased yield of rice Was about 67.5 × 104 ton in Japan. There have been many studies on blast disease for a long time. Tanaka and Katsuki (7)studied the relation between environmental conditions and blast disease. They always used adult healthy rice plants as plant materials and have not analysed the plants damaged by blast fungus directly. They suggested the presence of growth-promoting factors of blast funngus especially in susceptible rice varieties. Tamari and Kaji (5, 6) suggested that the blast fungus produced some effective toxic substances which might cause the disease. Suzuki, Doi and Toyoda (4) continued to study the mechanism of rice blast resistance and they have proposed 3 phases of resistance. They are (a) resistance and environtmental factors, (b) resistance and host camponents and (c) relation of host variety to fungus race.  相似文献   

15.
Abstract

Several silicon (Si) extractants are being employed in different countries mostly for lowland acidic soils. Present investigation was conducted to evaluate suitable extractants for upland paddy grown on alkaline soils. Available Si was extracted by using ten different extractants. Tris buffer pH 7.0 (1:10) in Inceptisols showed positively highest and significant correlation with grain yield (r?=?0.870), grain Si uptake (r?=?0.887), straw yield (r?=?0.852), and straw Si uptake (r?=?0.919). However, 0.5?M acetic acid (1:2.5) in Vertisols showed positively highest and significant correlation with grain yield (r?=?0.810), grain Si uptake (r?=?0.852), straw yield (r?=?0.850), and straw Si uptake (r?=?0.929). The application of Si @ 200?kg ha?1 along with chemical fertilizers significantly increased yield and nutrient uptake of upland paddy on Vertisols. Tris buffer pH 7.0 (1:10) and 0.5?M acetic acid (1:2.5) were suitable extractant for Inceptisols and Vertisols, respectively based on its correlation with yield and nutrient uptake.  相似文献   

16.
In the previous article (1), montmorillonitic soils were disclosed to have the ratio of total exchange acidity to y1 less than 3.0 and no ralation of the degree of base saturation to the ratio, although the relation was suggested by AMONINE and WATANABE (2).  相似文献   

17.
A method is described for the rapid and simple assay of soil β-glucosidase activity. It involves colorimetric estimation of ρ-nitrophenol released by β-glucosidase activity when soil is incubated in McIlvaine buffer (pH 4.8) with ρnitrophenyl βd-glucoside and toluene at 30°C for 1 hr. The method has been applied to three different soils. The range of β-glucosidase activity in cultivated soils was from 10.1 to 15.2 mµ mole per min per gram of dried soil. Km value for ρ-nitrophenyl β-d-glucoside was 3.3 × 10-4 M. Optimum pH was 4.8.  相似文献   

18.
Abstract

The presence of 4-MeGln in the tulip plant was discovered by ZACHARIUS et al. (1954), and it was found that this amide generally occurred in the leaves of almost all the species of genus Tulipa (FOWDEN and STEWARD 1957a). The 4-MeGln compound has been detected in every part of the tulip plant, i.e., bulb scales, roots, basal plate, young shoots, leaves, stern, and flower (FOWDEN and STEWARD 1957a, b; OHYAMA 1986; OHYAMA et al. 1985, 1988a, b; ZACHARIUS et al. 1954, 1957). Especially 4-MeGln was found to be a major soluble N constituent in the leaves and stem of tulip of the flowering stage (OHYAMA et al. 1985; OHYAMA 1986).  相似文献   

19.
TJURIN (1) had proposed the use of organic solvent to fractionate humus. In his method, he extracted soils with benzene-alcohol (1 : 1) mixture in the SOXHLET's apparatus. The extract was dried at 80°C and weighed.  相似文献   

20.
In this paper are described the properties of filmy gel substances occurring in the Imaichi (Imaichi-tsuchi) and Shichihonzakura (formerly called Jobukanuma-tsuchi (2,5)) pumice beds. The properties of such filmy materials from the Kanuma (Kanuma-tsuchi) , Imaichi, and Kitakami pumice beds have been described by many investigators (1,8, 9, 10,12, 13, 14, 15, 19, ). KANNO et al. (9) concluded that they were a mixture of poorly crystalline montmorillonite, allophane, and free sesquioxides. However, the presence of montmorillonite as an important constituent has been disproved by MIYAUCHIA nd AOMINE (12), ho concluded that the gel films from the Kitakami and Kanuma pumice beds consist principally of imogolite.  相似文献   

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