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1.
Abstract

Concern has been expressed that large amounts of volcanic ash from the May 18, 1980 eruption of Mount St. Helens may have created potential nutritional problems associated with forage production in northern Idaho and eastern Washington to the extent that adjustments need to be made in soil test correlation data. The objectives of this greenhouse study were to: (1) determine the effect of varying amounts of volcanic ash mixed into soils of northern Idaho on total alfalfa biomass production, and (2) to determine the effect of various soil/ash mixtures on the nutrient concentrations of P, K, S, Ca, Mg, Mn and Zn in alfalfa.

Alfalfa was grown in eight different northern Idaho soils amended with differing levels of volcanic ash (0, 20, 35, 50 and 75%) in the greenhouse. The alfalfa seeds were inoculated and fertilizer P and S were added to all treatments. Total plant biomass and P, K, S, Ca, Mg, Mn and Zn plant concentrations were measured.

The eight soils were pooled for analysis and it was found that increasing amounts of volcanic ash increased alfalfa biomass production. Plant P, S, Ca, Mg and Zn concentrations also increased with increasing levels of ash. Conversely, increasing levels of ash resulted in lower alfalfa tissue K and Mn concentrations. There is no evidence to suggest that the highest levels of ash which fell in northern Idaho (700,000 kg/ha) inhibited alfalfa production. Consequently, there is no need for adjustments in soil test calibration data presently used for fertilizer recommendations for alfalfa.  相似文献   

2.
Montane volcanic ash soils contain disproportionate amounts of soil organic carbon and thereby play an often underestimated role in the global carbon cycle.Given the central role of Al and Fe in stabilizing organic matter in volcanic ash soils,we assessed various extraction methods of Al,Fe,and C fractions from montane volcanic ash soils in northern Ecuador,aiming at elucidating the role of Al and Fe in stabilizing soil organic matter(SOM).We found extractions with cold sodium hydroxide,ammonium oxalate/oxalic acid,sodium pyrophosphate,and sodium tetraborate to be particularly useful.Combination of these methods yielded information about the role of the mineral phase in stabilizing organic matter and the differences in type and degree of complexation of organic matter with Al and Fe in the various horizons and soil profiles.Sodium tetraborate extraction proved the only soft extraction method that yielded simultaneous information about the Al,Fe,and C fractions extracted.It also appeared to differentiate between SOM fractions of different stability.The fractions of copper chloride-and potassium chloride-extractable Al were useful in assessing the total reactive and toxic Al fractions,respectively.The classical subdivision of organic matter into humic acids,fulvic acids,and humin added little useful information.The use of fulvic acids as a proxy for mobile organic matter as done in several model-based approaches seems invalid in the soils studied.  相似文献   

3.
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   

4.
Abstract

A study was conducted to determine the influence of the volcanic ash deposition on the physicochemical characteristics of some soils of West Sarawak and to evaluate their suitability for some common crops. A total of seven common soil series of different geology and locations from West Sarawak were collected and analyzed for their physicochemical and dissolution analysis. For comparison, similar analytical procedures were conducted on selected volcanic ash soils of Indonesia and the Philippines. The Sarawak soils were classified as Inceptisol, Ultisol, and Oxisol. The soils were acidic and had relatively low CEC and exchangeable bases. The other laboratory analysis, however, were not conclusive in the results. The soils were evaluated for crops such as rubber, oil palm, rice, pepper, banana and tapioca. Most of these soils were rated as moderate (S2) to marginally suitable (S3), indicating insignificant contribution of volcanic ash into the fertility status of soils of west Sarawak regions.  相似文献   

5.
It has been reported by many workers that various soil properties influence the retention of boron added to soils, but there is little infomration on the relative importance of these properties to boron retention and there is something controversial in the published results regarding the effects of different soil properties such as organic matter content, soil reaction, available calcium content and texture on boron retention (15). The present study was undertaken to obtain more detailed informations on the relationships between boron adsorption and different properties of soils, and on comparative contribution of soil constituents such as organic matter, sesquioxides and inorganic colloids to boron adsorption of soils. In Japan, boron deficiency symptoms of crops often appear in the fields of volcanic ash soils, and many experiments on boron application have been conducted to amend the boron deficiencies of the soils. It is considered that volcanic ash soils may have special characteristics concerning boron retention in comparison with nonvolcanic ash soils. In the present study, therefore, some volcanic ash soils were also taken as samples in addition to non-volcanic ash soils to confirm their speciality to boron retention.  相似文献   

6.
The consistency limits of some volcanic ash soils of south Chile. Consistency limits of 15 different soils with high volcanic ash contents, located in Southern Chile, were tested by means of the DIN-18.122 procedure and the liquid limit also by the cone penetrometer method. The liquid limit of holocenic volcanic ash soils is profoundly influenced by carbon content, and the plastic limit by exchangeable cation capacity and carbon content. In pleistocenic volcanic ash soils, the liquid limit is determined by silt and carbon contents, the plastic limit by carbon content and the plasticity index only by clay content. No significant correlation was found between the Casagrande method and that of the cone penetrometer.  相似文献   

7.
It is essential to analyze chemical properties including the amount of various materials and the soil colloid characteristics in forest soils to forecast wood production and the distribution of and variations in the environmental functions of forest soils, such as conservation of stream water and carbon sequestration. Approximately 70% of the forest soils in Japan consists of Brown Forest Soils (BFS), which are considered to be typical zonal soils under the humid-temperate and warm-temperate regime of Japan. BFS were subclassifled into several groups according to the soil moisture environment along the slope and morphological properties. However, even the same type of soil may display different properties depending on the climatic conditions, parent materials and vegetation types. In the present study, the variations in the carbon content, nitrogen content, cation exchange capacity and some properties depending on the parent materials, were clarified by using 34 sola of BFS, and 3 sola of black soils (BLS) for comparison, which were distributed in the submontane zone of the Kanto and Chubu districts in central Japan under the same climatic conditions. We observed differences in the pH, cation exchange capacity, base saturation and clay content among BFS samples derived from various parent materials. The BFS derived from volcanic ash contained obviously larger amounts of carbon and nitrogen than the BFS derived from other parent materials. However, the BFS derived from volcanic ash differed from the BLS derived from volcanic ash in the vertical distribution pattern of carbon and nitrogen. Thus, even in the submontane zone of the Kanto and Chubu districts, the chemical properties of BFS varied considerably with the parent materials. It was concluded that the classification of BFS by the parent materials was useful for evaluating the ability of the BFS, that cover 70% of the forests in Japan, to store various materials.  相似文献   

8.
Abstract

The objective of the present study was to clarify the influence of volcanic ash addition on soil carbon stocks and the carbon accumulation process in brown forest soils (BFS) in Japan. The degree of volcanic ash addition to the soil was estimated according to the acid ammonium oxalate extractable aluminum (Alox) and lithic fragment contents, and their vertical distribution patterns. The BFS was classified in order of increasing volcanic ash influence on the soil into the following types: high Alox content with no gravel (H-Alox-NGv), high Alox with a high gravel content (H-Alox-Gv), moderate Alox (M-Alox), and low Alox (L-Alox), and then analyzed for carbon content, carbon amount, carbon stock, Alox amount and pyrophosphate extractable aluminum (Alpy) amount. The correlation between the carbon and Alpy amounts and the relationship between the Alpy and Alox amounts in the BFS samples indicated that the amount of carbon is determined by Al—humus complex formation, which is defined by the active Al generated from additional volcanic ash in BFS soil samples of BFS. Therefore, soils with thicker horizons and greater amounts of Alox had higher carbon levels in deeper horizons. For this reason, soil carbon stocks at depths of 0–30 cm and 0–100 cm, and in the effective soil depth of BFS, were larger and followed the order H-Alox-NGv = H-Alox-Gv > M-Alox > L-Alox. Furthermore, successive accumulations of volcanic ash on the soil surface promoted soil carbon accumulation as a result of the development of the surface horizon in H-Alox-NGv BFS. Our results suggest that volcanic ash additions control the soil carbon accumulation of forest soil in Japan.  相似文献   

9.
Abstract

Surface soils from ten soil series representing five great groups were collected from Alaska. These soils were selected from the important agricultural areas covering a wide geographic distribution. These soils can be divided into two distinct groups based on their parent material: loess and volcanic ash. Phosphorus sorption maxima were calculated based on the Langmuir isotherms. The volcanic ash soils (Cryandept and Cryorthods) showed an average P‐sorption maxima of 10,122 mg/kg and loess soils averaged 3,934 mg/kg. Both groups have similar portions of phosphorus in the organic form (19%) and occluded form (8 to 9%). The nonoccluded‐P in the volcanic ash soils and the loess soils was 68% and 43% respectively, and the Calcium‐P was 4% and 29% respectively.

Regression analysis indicated that aluminum and iron are primarily responsible for P‐sorption. The dithionite extractable Al is responsible for P‐sorption in volcanic ash soils, while oxalate extractable Al is responsible for P‐sorption in loess soils. Dithionite and oxalate extractable Fe probably play a secondary role in P‐sorption. The sorption isotherm, regression analysis and the P‐fractionation data provide the agronomist with useful information to estimate P requirement of newly cleared soils.  相似文献   

10.
Abstract

A method to determine the contents of imogolite and Al-rich allophane (Sil Al ? 1 : 2) in volcanic ash soils was presented. The method is based on the (1) assessment of the presence of Al-rich allophane in clays by successsive extraction with dithionite-citrate and oxalate-oxalic acid, (2) trimethylsilylation of soil clay with a mixture of hexamethyldisiloxane, HCl, and isopropyl alcohol, and determination of the content of monomeric Si based on the trimethylsilyl derivative of monomeric orthosilicate anion by gas / liquid chromatography, (3) determination of the total content of imogolite and Al-rich allophane based on the content of monomeric Si from imogolite, (4) determination of the imogolite content by Thermogravimetry (TG )-Differential Thermal Analysis (DTA) based on the weight loss due to endothermic dehydroxylation with maximum values at ca. 386°C, (5) calculation of the Al-rich allophane content by subtracting the imogolite content from the total content of these minerals, and (6) evaluation of the imogolite and Al-rich allophane content of soil by multiplying clay content of soil and the two mineral content of clay. The trimethylsilylation analysis was found to be reproducible, and the estimated total amounts of two minerals in clays by this method were adequately approximated to those evaluated from the amount of Si (= Sio) extracted with oxalate-oxalic acid after extraction with dithionite-citrate. The variation in the abmldance of two minerals in the soil horizons of volcanic ash soils from the San'in region indicated that this method is suitable for the profile-study of volcanic ash soils.  相似文献   

11.
The physical, chemical, and mineralogical properties as well as the micromorphology of five indurated volcanic ash soils in Kyushu, Japan were investigated. The indurated soils were divided into two types based on the physical and chemical properties. Type 1 was not indurated in its moist state, but shrank and became very hard by air-drying. Type 1 included the buried volcanic ash soils whose physical and chemical properties were similar to those of other buried volcanic ash soils except for the property of induration by air-drying. The mechanism of the induration is still unknown, although it is considered to have occurred during the long period after the deposition of tephra under the influence of soil formation processes. Type 2 included the tephra layers that were indurated in both moist and air-dried states. The carbon and clay contents of type 2 were remarkably lower than those of type 1. Type 2 had not been affected by the soil formation process but had undergone induration soon after the deposition of the tephra. Neither type 1 nor type 2 could be classified into any indurated horizons that are defined in the present soil classification system. For the improvement of soil productivity, type 1 should be harrowed thoroughly soon after its exposure to the surface, and type 2 should be harrowed or removed using farm machinery.  相似文献   

12.
The environs of Mt. Daisen, Tottori Prefecture, are generally mountainous or hilly, and apart rom small areas of alluvial and coastal flats there is little level ground. The volcanic ash soils derived from the quartz biotite hornblende andesitic ejecta occur on the gently undulating foot-hill and on the level ground with exception of alluvial flats. Considering the fact that these soils were formed from not only volcanic ash but the coarser materials, they may be properly called volcanogenous soils. The volcanic ejecta have been deposited on the soils from diluvial series, andesite, basalt, granite, and tertiary sedimentary rocks. It was recognized that in an eruption the large ejecta, such as fine porous pumiceous lapiili descended first, then the smaller Particles such as sands, and finally the smallest, as ashes. All of these deposits have been highly weathered, but the quartz and hornblende remain in a fresh state1). The author has studied some characteristics of these volcanic ash soils.  相似文献   

13.
Our knowledge of effects of land use changes and soil types on the storage and stability of different soil organic carbon (SOC) fractions in the tropics is limited. We analysed the effect of land use (natural forest, pasture, secondary forest) on SOC storage (depth 0–0.1 m) in density fractions of soils developed on marine Tertiary sediments and on volcanic ashes in the humid tropics of northwest Ecuador. The origin of organic carbon stored in free light (< 1.6 g cm?3) fractions, and in two light fractions (LF) occluded within aggregates of different stability, was determined by means of δ13C natural abundance. Light occluded organic matter was isolated in a first step after aggregate disruption by shaking aggregates with glass pearls (occluded I LF) and in a subsequent step by manual destruction of the most stable microaggregates that survived the first step (occluded II LF). SOC storage in LFs was greater in volcanic ash soils (7.6 ± 0.6 Mg C ha?1) than in sedimentary soils (4.3 ± 0.3 Mg C ha?1). The contribution of the LFs to SOC storage was greater in natural forest (19.2 ± 1.2%) and secondary forest (16.6 ± 1.0%) than in pasture soils (12.8 ± 1.0%), independent of soil parent material. The amount of SOC stored in the occluded I LF material increased with increasing silt + clay content (sedimentary soils, r = 0.73; volcanic ash soils, r = 0.58) and aggregation (sedimentary soils, r = 0.52; volcanic ash soils, r = 0.45). SOC associated with occluded I LF, had the smallest proportion of new, pasture‐derived carbon, indicating the stabilizing effect of aggregation. Fast turnover of the occluded II LF material, which was separated from highly stable microaggregates, strongly suggested that this fraction is important in the initial process of aggregate formation. No pasture‐derived carbon could be detected in any density fractions of volcanic ash soils under secondary forest, indicating fast turnover of these fractions in tropical volcanic ash soils.  相似文献   

14.
In Japan, most of the paddy fields are laid out on alluvial plain while other land crop fields are developed on plateau. The greater part of the latter ccnsists of volcanic ash soils.  相似文献   

15.
Texture is one of the major criterions in soil classification, probably because it has a decisive influence on soil properties. This is particularly true for volcanic ash soils. Most ashes are largely composed of sand and silt particles with little clay (11, 15). The ash weathers very rapidly (1), and clay site particles less than 2 microns in diameter occur even within a few months, as shown by Ishii at the authors' laboratory. Those clay size particles produced in the early stage of weathering are slightly weathered ones (2), and are still subject to rapid weathering, losing bases and silica under humid and well drained conditions. In consequence the clay fraction of volcanic ash soils is composed of particles which vary in degree of weathering from slightly altered glass and feldspar to true clay mineraloids and minerals. The clay fraction of younger soils as a whole is less and that of older ones is more weathered. Weathering brings a remarkable change in the properties of volcanic ash soils; for example, an inerease in soil acidity, lowering of base saturation and bulk density, or accumlation of organic matter. These changes must exert a great influence on soil fertility directly or indirectly.  相似文献   

16.
The use of tephrochronological data on the ages of volcanic eruptions and the corresponding ash layers buried in the profiles of forest soils in Kamchatka makes it possible to distinguish between two groups of volcanic soils related to different stages of the volcanic activity. In the Holocene, the southern group of volcanoes was characterized by the ejection of acid pyroclasts typical of the mature stage of volcanism (the stage of caldera formation). The northern group of volcanoes ejected basic pyroclasts typical of the early (basaltic) stage of volcanism. Thus, the effect of the full cycle of volcanism on the soil formation can be traced in the soil profiles. It is shown that soil formation in volcanic areas depends on the frequency and intensity of ash falls and on the composition of the pyroclastic material.  相似文献   

17.
The influence of mean annual rainfall and soil texture on the 137Cs vertical distribution in soils from southern Chile The influence of mean annual rainfall and soil texture on the vertical distribution of 137Cs from global fallout was studied in undisturbed volcanic ash soils from southern Chile. The areal concentration and translocation depth increase with the mean annual precipitation. In spite of the high rainfall at the sampled area (970 - 2500 mm a?1), the highest 137Cs contamination was found in the upper 10 cm layer. The vertical migration is reduced by the high adsorption capacity of these volcanic ash soils, but on the other side increased in soils with high large-pore volumen. The translocation depth reaches only up to 26 cm in the clay soils, 35 cm in the silty soils and 70 cm in the sandy soil.  相似文献   

18.
The clay mineralogical composition of soils on volcanic ashes from Mashū and Kamuinupuri-dake volcanoes, Hokkaido, which are rich in cristobalite, was determined using petrological, X-ray diffraction, differential thermal, and selective dissolution and differential infrared spectroscopic methods.

The cristobalite occurred in abundance in every size of fraction from coarse sand to clay and every soli from approximately 1,700 to 8,400 years old, and was concluded to be of igneous origin. The major clay minerals were allophanelike constituents and allophane with some layer silicates as the minor clay mineral, being similar to those of andesitic ash soils and different from those of volcanic ash soils containing abundant quartz. The quartz of volcanic ashes was presumed to bederived from the groundmass-equivalent portion of the ashes which had been formed from magma at a low temperature.  相似文献   

19.
To elucidate the influence of climate and vegetation upon the vertical distribution of soil moisture and its seasonal change is one of the fundamental problems in the studies on water economy of volcanic ash soils, that cover the larger parts of Japan, and have characteristic soil-water system.1) Few data are now available in this field, despite the fact that management of volcanic ash soils is practically one of the most urgent problems in Japan.  相似文献   

20.
中国的火山灰土   总被引：5，自引：0，他引：5       下载免费PDF全文
赵其国 《土壤学报》1988,25(4):323-329
中国火山灰土的分布面积甚小,大致可分为蒙古高原、西藏高原及太平洋三个区,本文对中国海南岛的雷虎、云南的腾冲、黑龙江的德都及辽宁的长白山四地区火山灰土的发生特性及分类问题进行初步讨论。1.火山灰母质大多为火山灰,地形为台地、土层浅薄,色呈棕黑,土体含玻璃碎屑,粉砂中含有斜长石、辉石等可风化矿物。土壤容重小,孔隙度与持水能力高,毛管持水量接近饱和水含量。土壤呈微酸至中性,代换性Ca++及全磷、全钾含量甚高。2.火山灰土土体全量组成中CaO、MgO、Na2O、TiO2含量甚高,CaO含量几乎与母质含量相当。土壤微量元素以Ni、V与Zn为主,并随母质到土层有所增加。粘土矿物为硅酸盐非晶物质,以水铝英石为主。3.由于受不同的自然条件与发育年龄影响,火山灰土除具有上述共同特性外,它们之间,在有机质含量及酸度,铁与铝的富集度及土壤淋溶强度等方面均有所差别,这些差别正是火山灰土不同发育程度的反映。4.按研究结果,初步提出将中国火山灰土列入初育土土纲,并按其发育程度分为粗骨性火山灰土(D-117,T-8),轻度发育火山灰土(C-10,T-3)及中度发育火山灰土(R-4)。  相似文献   

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