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1.
土壤中积累态磷活化动力学的研究Ⅰ.有机质的影响 总被引：12，自引：0，他引：12
研究了潮土和红壤中积累态磷的活化动力学及其有机质的影响。四种动力学方程均能很好地描述积累态磷的活化。用H2 O2 去除有机质加快了潮土中积累态磷的活化 ,对红壤影响不明显。施加 2 %葡萄糖培育促进了红壤中积累态磷的活化 ,对潮土影响不大 相似文献
2.
Th. Beck 《植物养料与土壤学杂志》1984,147(4):467-475
Microbiological and biochemical characteristics of agricultural soils Part. II. Relations to the organic matter content A soil microbiological index for 33 tested samples of 11 agricultural soils with different origin and management history was correlated with the corresponding organic carbon content. The soils tested showed a highly significant correlation coefficient (r = 0.93) between the microbiological index and the total organic carbon content. According to our working hypothesis, there seems to be a connection between the quotient which is derived from the microbiological index and humus content to the turnover of organic matter in soils. In individual soils or groups of soils the deviations from the general function calculated from all tested soils are not caused by errors in the analytical procedure. They seem to indicate changes in the humusstatus (intensity of humus synthesis or humus decomposition) occuring during the time of investigation. 相似文献
3.
John M. Galbraith 《Soil Science and Plant Nutrition》2018,64(2):190-199
ABSTRACT Human-altered and human-transported (HAHT) soils are widespread across the globe and are concentrated near where people live and work. Although some of the HAHT soils are significant because they can be hazardous to human, animal, and plant health, most are not mapped or classified to the same extent as agricultural soils. The purpose of this article is to discuss the occurrence, types, and importance of HAHT soils and to document the historical and proposed classification of HAHT soils in Soil Taxonomy. There are two main forms of materials that define HAHT soils: human-altered soils formed in human-altered materials (HAM) from the soil surface to 50 cm (or to bedrock if shallower) or more and human-transported soils formed in human-transported materials (HTM) from the soil surface to 50 cm (or to bedrock if shallower) or more. The HAHT soils mainly occur in urban areas, transportation corridors, mined lands, landfills, filled shallow water, and agricultural areas on anthropogenic landforms. Hazards include danger from radioactivity, pollution, content of hazardous artifacts, or presence on unstable landforms that may fail during heavy rains or earthquakes. The HAHT soils are extensive, and their extent is growing. In the past, few HAHT soils were described or classified adequately because the U.S. Soil Taxonomy system was established for agricultural and other naturally occurring soils. However, HAHT soils are now being recognized and classified in many soil classification systems at very high levels. A new soil order is proposed for U.S. Soil Taxonomy that would include the most obvious profoundly and intentionally altered HAHT soils. A discussion and justification is given for an unofficial proposal. Input will be collected from international groups of scientists, and modifications of the unofficial proposal are expected. The long-term result of establishing a new soil order will be to enable proper classification, allocation, and mapping of HAHT soils worldwide. 相似文献
4.
BJARNI HELGASON 《European Journal of Soil Science》1968,19(1):127-134
Data for mechanical and chemical analyses are presented with tabulated mean and median values based on fifty-five freely drained and ten poorly drained soils. The soils are relatively coarsed textured. The sand content of the mineral fraction is about 70 per cent (mean value) for freely drained and about 45 per cent (mean value) for poorly drained soils. Organic C is generally high in freely drained soils but relatively low in poorly drained soils, because of accumulating aeolian matter in the latter group, mean values are 8.2 in freely drained and 16.5 per cent in poorly drained soils. The C/N ratio is about 15 for each soil group. The cation exchange properties including pH seem to be dominated by organic matter, which may contribute to the total CEC of the soils about 165–300 me/100 g C. CEC of soils is usually 40–50 me/100 g. For some selected soils CEC of the separated mineral fractions was confirmed experimentally through ammonia retention. The pH level, especially of the freely drained soils, is relatively high (mostly 5.4–6.3) in spite of low degree of base saturation (mostly 10–30 per cent), a characteristic probably derived from the parent material. A highly significant correlation exists between pH and organic C. Proportionally exchangeable Ca seems low, while Mg and Na may be abundant. In some soils exchangeable Mg may exceed Ca. 相似文献
5.
In southwestern Indiana, the Sangamon paleosol transgresses Illinoian glacial drift and weathered bedrock of Pennsylvanian and Mississippian ages in an unglaciated area. The paleosol is buried beneath Wisconsin age loess that thins from 3.2 to 0.5 m in a distance of 83 km eastward from the Wabash River Valley. The buried soil is redder, has more clay in the illuvial horizon, and also has a thicker solum than overlying ground soils formed in loess. Base saturation and pH states of the paleosol relate to secondary enrichment after burial. Free iron-oxide content relates to redder colors and is a genetic property of the buried soils. Greater depletion of illite and chlorite in the paleosol shows that it is more weathered than the overlying ground soil. Pedologic contrasts permit recognition of the Sangamon stage as an event of greater magnitude in the Quaternary than all postloess and Recent time in southwestern Indiana.The Sangamon paleosol has the redder colors and forest-soil profiles on well-aerated, upland, paleogeomorphic sites for a distance of 1000 km to the west. The Sangamon environment probably was uniformly warm, humid forest and woodland not unlike the climatic-vegetation pattern in southern United States today. The present ground soils have more diverse patterns ranging from forest soils in Indiana westward through grassland prairie soils to grassland chernozemic soils of the easternmost Great Plains and with related humid to dry subhumid climates. 相似文献
6.
《Communications in Soil Science and Plant Analysis》2012,43(3-4):577-591
Abstract Potassium (K) fixation in soils treated with K‐rich fertilizer is important in limiting leaching of this ion, and thus the risk of high salinity in waters. We studied this capacity for aqueous suspensions of a group of soils of Galicia (N.W. Spain) and found that fixation increased with K dosage, increased slightly with contact time, and decreased with increasing temperature (between 3 and 40°C). Potassium fixation was barely influenced by the mineralogy of the clay fraction but was greater in soils with greater fine particle content. Modified Freundlich equation successfully modelled the effects of K addition, temperature, and contact time on fixation. The influence of temperature was greater in illitic soils than in mixed soils. The results indicate that Galician soils have little capacity for K fixation. 相似文献
7.
Werner Müller-Ahlten 《植物养料与土壤学杂志》1994,157(5):333-343
On the genesis of tidal marsh soils II. Carbonate sedimentation, decalcification A central problem of the tidal-marsh soils is the calcareous deposit of the parent material. On the basis of small-scale, systematic investigations it has been demonstrated in two “key areas” in the Weser tidal flats, that fluviatile and brackish soils are descended from calcareous or not-calcareous sediments. Soils buildet from calcareous sediments shows a low depth and a low rate of decalcification because of a high content of clay and bases as well a permanent high level of groundwater during the development of the soils. 相似文献
8.
In Schleswig-Holstein, F.R.G., two typical soil associations from loamy boulder marl and loamy pleistocene sands were mapped and ecologically characterized in order to show the necessity of an adequate classification of Colluvic Cumulic Anthrosols (Colluvisols). More than 50% of the original soils have been altered by erosion. The depth of the colluvic wM horizon ranges between 10 cm and more than 100 cm. The amounts of soil organic matter and plant available nutrients are much higher in the Colluvisols than in the haplic soils. Soil classification does not deal with all these aspects with regard to mapping of colluvic soils. In the German soil classification adequate and ecologically significant definitions and instructions of the nomenclature of colluvic soils are not available. Therefore, a proposal is presented to classify colluvic soils. In addition the threshold value of 0.6% soil organic matter in sandy parent material is too low in order to distinguish a Bv from a M horizon; 1.0% would be a more acceptable value. It would be necessary to investigate yield on erodic, non-erodic and colluvic soils in order to determine the effect of erosion and accumulation on crop yield. 相似文献
9.
《Geoderma》1987,39(3):249-265
Chemical and surface charge characteristics were determined for three soils that were formed in a mantle of volcanic tephra along a bio-climatic gradient in forest in northcentral Washington state. The soils are Nevine silt loam (Typic Vitrandept), Manley silt loam (Entic Cryandept), and Moses silt loam (Andic Cryochrept). Selective dissolution analyses for Al, Fe, and Si suggests that the weathering products in the ash mantle are poorly crystalline aluminosilicates, hydrous and crystalline Fe-oxides, and Al-humus complexes in decreasing order of abundance. The chemical and physical data indicate that Moses silt loam has undergone a greater degree of weathering than either Nevine silt loam or Manley silt loam, and we attribute this to differences in the weathering environment. The measured points of zero charge parameters are typical for soils that are dominated by amphoteric surfaces: the soils exhibit charge reversal, and charge magnitude is dependent upon pH and electrolyte concentration. The point of zero salt effect ranged from 5.1 to 5.3, and the point of zero net charge ranged from 4.3 in Nevine silt loam to 5.4 in Moses silt loam. Pedogenesis has not caused large enough differentiation among the soils to allow us to use zero charge parameters as indicators of the degree of pedogenesis. 相似文献
10.
以强烈生物活动参与和外源有机质输入为发生学基础、以鸟粪矿化与下部岩石层磷化作用为主要发生学过程的鸟成土在南极海洋气候区广泛分布,形成独特的海岸带土壤景观。本文对南极海洋气候区内鸟成土的发生学特点、剖面形态特征、新成矿物主要类型及其发生机制进行了论述;对鸟成土随栖息地遗弃向残积鸟成土演变的过程进行了阐述。在上述基础上,论述了本区内鸟成土在发生、发育与演化过程中相对于南极其他地区鸟成土所表现的特殊性。 相似文献
11.
Water, Air, & Soil Pollution - The effects of acid rain on surface horizons of five soils from Galicia and the buffer capacity of these soils with respect to the addition of H` were studied.... 相似文献
12.
The effects of acidic deposition on agricultural soils have not received much attention because they are regularly limed and receive acid forming fertilizers far in excess of what would accumulate in these soils from atmospheric acidic deposition. However, not all agricultural soils are managed with equal intensity, and some may be prone to element specific effects from acidic deposition. Using data from the West Virginia University Soil Testing Laboratory and the National Atmospheric Deposition Program,it was found that soil Mg concentrations were decreasing up to 2.6% yr-1 in hay and pasture soils where acidic deposition was the highest. Rainfall amounts and biomass removaldid not appear to be related to this effect. By comparison, no trends in Mg depletion with acidic deposition were found for the more intensely managed home garden soils. Nor were there regional trends in Ca or K for either hay and pasture or home garden soils. While the correlation Mg depletion and acidic deposition does not in and of itself indicate causality, it does suggest the Mg status of unmanaged or moderately managed grasslands may be adversely affected by acidic deposition. 相似文献
13.
Rog B. Parsons 《Geoderma》1978,21(1):25-39
The development and distribution of soils in the Coast Range and Klamath Mountains are related to geomorphic surfaces and slope gradients. Soils over basalt, studied in the Coast Range, were formed in transported materials and include examples of more than a half dozen great groups of the Alfisol, Inceptisol, Mollisol, and Ultisol orders. Distribution patterns of the soils can be related to active slopes, metastable slopes, pediments, ridge tops, flood plains, and alluvial fans. Variables among the factors of soil formation in the Coast Range are chiefly geomorphic surfaces and parent materials.Soils of a lithosequence of pyroclastics, granite and schist in the Klamath Mountains include examples of great groups in the Entisol, Inceptisol, and Mollisol orders. All soils from pyroclastics have argillic horizons, those from granite lack argillic horizons, and those from schist lack argillic horizons except on relatively stable surfaces. Average thicknesses of soils over saprolite range from 76 cm over granite and schist to 150 cm over pyroclastics.Lithologic discontinuities are common in both mountain areas. Field techniques for identification, described briefly, include stone lines, irregular distribution of rock fragments with depth, thicknesses of weathering rinds on rock fragments, and the lateral extensions of soil horizons. 相似文献
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16.
Morphological, physical, chemical and mineralogical data are presented for contiguous euchrozem (nitosols) and chocolate soils (cambisols) developed on basaltic parent materials in the Armidale district of northern New South Wales. The genesis and distribution of the different soils classified at great soil group and series level are related to parent material and topography. The dark brown chocolate soils associated with the modern surface overlie a uniform parent material of partly weathered alkali-olivine basalt. The red euchrozem soils, although having morphological and mineralogical properties associated with intensive weathering and long term soil genesis, have also developed on the modern surface under a moderate leaching regime. They are derived from re-exposed, highly weathered, sesquioxidic, interbasaltic lapilli tuffs and underlying basalt which were probably transformed under a different climate in Pliocene—Pleistocene times. The study showed further that reddish chocolate soils are not necessarily the uppermost member of a sequence of soils developed on partly weathered basalt. 相似文献
17.
Contaminated soils and surface waters, from copper mining in Galicia, are acidic, high in sulphate and increase appreciably in the concentration of elements such as Al, Fe, Ca, Mg, K, Mn, Cu and Zn by contact with soils and fragments of rock of an amphibolic composition. Application of activity data to mineral equilibrium diagrams illustrates the instability of Al-hydroxides and aluminosilicates compared to Al-sulphates of the alunite and jurbanite type, in the waters which are most acid and display sulphate activities close to 10?2 M. The solution extracted from soils around the spoil heaps reflects the strong influence of the most heavily contaminated run-off waters, with little or no buffering by the solid phase. This aspect may be accounted for by both a brief time of residence and a real decrease of the acid buffering power of these soils, whose primary minerals undergo strong acidolysis. Neoformation of Al-sulphate (and Fe-sulphate) is observed both in soils and in the channels of the contaminated streams, above all the points of contact with non-acid or slightly acid waters. 相似文献
18.
土壤中积累态磷活化动力学的研究Ⅱ.沸石的影响 总被引：5，自引：0，他引：5
本文研究了NH4-沸石对潮土和红壤中积累态磷的活化动力学的影响。修正的Elovich公式和双常数速率公式对土壤中积累态磷的活化动力学拟合最好。土壤中添加了NH4-沸石后 ,土壤中积累态磷的活化释放明显增快。NH4-沸石有较强的释磷作用 ,可以促进土壤中积累态磷的活化释放。 相似文献
19.
Cross polarisation 13C-n.m.r. spectra of seven New Zealand soils have been determined. Some of the soils are genetically related. The results show that the aromaticity of a soil may vary widely from soil to soil even when the parent material and vegetation are similar. The youngest of the soils examined (Hokitika, 300 years), was highly aromatic, and the oldest soil (Okarito, 22,000 years) was more aliphatic. 相似文献