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1.
Evaluation of soil transformations and degradation is important not only for agriculture, but also for fundamental research on identification of new features for classification. In 1999, new Lithuanian soil classification (LTDK-99) was developed by adopting the diagnostic principles of WRB 1998. Together with new knowledge, it highlighted some relevant soil research and classification problems. Not only new terms but also diagnostic features of several newly distinguished first-level soils groups are being discussed, especially for the identification of cambisols, planosols, arenosols, and regosols. Additionally, a group of stagnosols is suggested for inclusion into this classification. The presence of glaciogenic secondary clay minerals in Lithuanian cambisols does not imply unambiguous brownification involvement, neither any study shows cambisols having specific to brownification iron minerals. The intensively occurring lesive in these soils questions correctness of identification of cambisols additionally aggravated by strong and deep anthropogenization of the soil profiles within the territorial range. Complex glaciogenesis makes it difficult to identify Lithuanian planosols. WRB 2014 (update 2015) identifies planosols according to the pedogenesis in old, strongly weathered binomial deposits using examples mostly from South American, South and East African plateaus of the subtropical zone. The same classification assigns planosols identified in Lithuania to stagnosols, that is, to the soils characterized by binomial genesis and stagnification. The diagnostic features of arenosols and regosols are similar in both groups and are related to primitive pedogenesis. Difficulties in distinguishing between the two groups in Lithuania are strengthened by the intensive cultivation of the ecosystems in their territorial range. The existing problems in Lithuanian soil diagnostics underline the questions of soil classification in general, especially regarding the evolution tendencies in soil classification. The article draws attention to the soil diagnostic aspects like distribution and genesis of clay particles, genesis of territory, and anthropogenic transformation for the improvement of soil identification.  相似文献   

2.
武夷山土壤形成特点与系统分类   总被引:15,自引:0,他引:15  
陈健飞 《土壤通报》2000,31(3):97-101
选取武夷山土壤垂直带中 6个代表性剖面 ,研究了土壤的形成条件和特点 ;按照《中国土壤系统分类 (修订方案 )》 ,鉴定了诊断层和诊断特性 ,检索了土壤系统分类名称 ;随海拔由低到高 ,依次为湿润富铁土—湿润淋溶土—常湿淋溶土—常湿雏形土等亚纲 ;并与发生学分类、美国土壤系统分类 (USST)以及世界土壤资源参比基础 (WRB)等不同分类系统中的土壤类别归属作了参比  相似文献   

3.
杭州市城市土壤中重金属、磷和其它元素的特征   总被引:30,自引:0,他引:30  
Health implications of inhaling and/or ingesting dust particles with high concentrations of heavy metals from urban soils are a subject of intense concern. Understanding the geochemistry of these metals is key to their effective management. Total concentrations of heavy metals, phosphorus (P) and 8 other elements from topsoil samples collected at 82 locations in Hangzhou City were measured to: a) assess their distribution in urban environments; and b) understand their differentiation as related to land use. Metal mobility was also studied using a three-step sequential chemical fractionation procedure. About 8.5%, 1.2%, 3.6%, 11.0% and 30.3% of the soil samples had Cd, Cr, Cu, Pb, and Zn concentrations, respectively, above their allowable limits for public and private green areas and residential use. However, in commercial and industrial areas, most samples had metal concentrations below their allowable limits. Statistical analyses revealed that the 16 measured elements in urban soils could be divided into four groups based on natural or anthropic sources using a hierarchical cluster analysis. Additionally, Cu, Pb, and P showed similar spatial distributions with significant pollution in commercial zones, suggesting vehicle traffic or commercial activities as dominant pollutant sources. Also, Cd, Co, Cr, Ni, Zn, Mn and Fe had the highest concentrations in industrial locations, signifying that industrial activities were the main sources of these seven metals. Moreover, the data highlighted land-use as a major influence on heavy metal concentrations and forms found in topsoils with large proportions of soil Cd, Co, Cr, and Ni found in residual fractions and soil Cu, Pb and Zn mainly as extractable fractions.  相似文献   

4.
草原土壤:分布、分类与演化   总被引:2,自引:1,他引:2  
龚子同  张之一  张甘霖 《土壤》2009,41(4):505-511
草原土壤系指草原、湿草原和森林草原植被下形成的富含有机质、盐基饱和度高的暗色土壤.世界上此类土壤面积约900万km2,我国约76万km2,是粮食生产的重要基地.本文比较了国际上草原土壤分类.不论俄罗斯或中国,均腐土开垦以后土壤有机质开始下降迅速,而后减缓,逐步达到与当地生物气候相适应的水平.所以至今仍保持一定厚度的黑土层.在均腐土资源的利用和保护上,一方面应保持其有机质平衡,另一方面更重要的是严防水土流失,以保证其生产能力.  相似文献   

5.
Pedohydrological properties were investigated on a piped slope in the Bergisches Land in the Rhenish Slate Mountains (Nordrhein‐Westfalen, Germany). The study confirmed that genesis and development of pipes decisively depend on hydrological conditions in the soils. Vertical water permeability of saturated samples was very high. This promoted fast seepage. Many macropores produced by earthworms also caused high transport capacity for soil water. Even more efficient were the burrows of moles and mice, enabling immediate infiltration and direct vertical and lateral water movement. On the contrary, the horizontal saturated permeability was low indicating no correlation with piping. Porosity of piped soils was not different to that of other soils of the region without pipes.  相似文献   

6.
The taxonomic hierarchy and nationwide distribution of soils with a salic horizon were studied using the USA Natural Resources Conservation Service Soil Survey Geographic (SSURGO) Database to provide a more holistic view of the role of soil-forming factors in pedogenesis than from isolated case studies.Soils with a salic horizon occupied an area of 11 000 km2,i.e.,0.1% of land area in the contiguous USA.These soils occur narrowly in three great groups(Aquisalids,Haplosalids and Halaquepts),11 subgroups,and 97 soil series.Soils with a salic horizon commonly had a mesic (50% of soil series) or thermic (19%) soil-temperature class,an aquic (89%) soil-moisture class,a mixed mineral class (79%),a calcareous (52%)reaction class,a superactive (59%) cation exchange activity class,and a fine (24% of soil series),fine-loamy (24% of soil series),or fine-silty (19% of soil series) particle-size class.Soils with a salic horizon were concentrated in the Basin and Range Province of western USA.The key pedogenic processes leading to the development of salic horizons were salinization,gleization,and calcification,with some evidence for argilluviation and silicification.  相似文献   

7.
Nature and significance of anthropogenic urban soils   总被引:14,自引:9,他引:5  

Background, Aims and Scope

Anthropogenic and natural urban soils are of increasing significance in a world with accelerating urbanization. Thus, anthropogenic urban soils must be considered as an fundamental ecological asset for land-use planning. Furthermore, they are of interest for fundamental soil sciences, since there properties are rarely investigated and can differ substantially from landscape soils. Numerous studies on their properties exist, in particular with respect to contamination. It is argued that urban soils are ecological assets of cities, a point of view shared with the AKS (working group on urban soils within the German Soil Science Society). In this commentary, an overview of less recognized topics is presented with specific reference to topics such as ‘co-development of anthropogenic urban soils within their cities’ and the principles of ‘stock flow of anthropogenic urban soils forming materials’ are discussed to complete the pedological and ecological view on urban soils. Additionally, the significance of (anthropogenic) urban soils is highlighted to strengthen consideration in urban spatial planning.

Main Features

Historical and recent impacts on soils and parent materials are related with soil properties. Definitions and taxonomic terms for anthropogenic soils are presented. Furthermore, the context with the functionality of such soils is discussed. The principles of mapping and evaluation of anthropogenic urban soils are explained to stress the practicability of management tools for such soils.

Results and Discussion

A semi-quantitative consideration of parent material flows in anthropogenic urban soils indicates the enormous increase of the areas of supply of cities since the pre-industrial period. Since 1950, the inner-urban deposition of solid materials, including dust stopped to increase or increases slowly in the early industrialized regions. In contrast, the deposition and reuse of rubble, inorganic and organic waste as well as dust increases much in the late industrialized regions of the last decades.

Conclusions

The significance of anthropogenic urban soils in ecological soil management became obvious by numerous scientific studies. Moreover, it is recognized that management of different areas in urban environments must respect the functionality of their soils. It is therefore of importance that pedology is integrated with related disciplines such as archaeology, history and urban planning. The scientific knowledge, the appropriate methods and tools are now available to promote and support the management of anthropogenic urban soils.

Recommendations and Perspectives

It is recommended that research conducted over the past two decades should be introduced into soil management, especially with regard to the evaluation of soil quality. Accordingly, results of collaborative studies by soil scientists and city planners need to be integrated into political frameworks like the European Soil Strategy. It is also recognized that knowledge regarding anthropogenic urban soils in the tropics, the southern hemisphere and far north is lacking, a point which will need to be addressed in the future.

Dedication

This publication is dedicated to the 20th anniversary of the AKS (Arbeitskreis Stadtböden).
  相似文献   

8.
Abstract. This paper describes a soil classification system developed for agronomists in Cambodia that has proved useful in improving soil fertility management. The classification system relies on soil characteristics that are easily identifiable in the field and have agronomic relevance. The system was used in the on-farm trial programme of the Cambodia-IRRI-Australia Project (CIAP) in 1996 and 1997 to determine whether it could adequately discriminate between soil types and improve fertility management.   Using diagnostic criteria that could be identified in the field, 11 soil groups were defined and subdivided into a further 20 phases. Soil groups were defined as units of morphologically similar soils, which occurred at the same position in the landscape. Classification of soil phases within a soil group was primarily based on soil properties that had significance for crop production, this included information gained from local experience and expertise. A modified version of the Fertility Capability Classification (Sanchez et al., 1982) was added as a third level to allow a more quantitative classification in cases where soil analytical data was available, and to facilitate the transfer of agronomically important soil information from outside Cambodia.   The soil groups adequately predicted differences in grain yields of rice grown on the different soils in on-farm trials and provided the basis for soil-specific management recommendations. Local agronomists have welcomed the system and have incorporated it into their research and extension operations.  相似文献   

9.
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   

10.
研究了安徽省合肥、芜湖和亳州市周边蔬菜地土壤和蔬菜中PAHs的含量及其污染特征。结果表明:安徽省典型蔬菜地土壤中15种PAHs(除萘外)的残留总量在58.2~437.8μg·kg-1之间,三环和四环PAHs占PAHs残留总量的70%以上。胡萝卜、菠菜和茄子体内15种PAHs的含量在23.4~209.1μg·kg-1之间,均值为120.7μg·kg-1,三环和四环PAHs占蔬菜中PAHs富集总量的92.8%~94.4%。不同蔬菜体内8种可疑性致癌PAHs的含量在11.5~17.4μg·kg-1之间,分别占蔬菜中PAHs残留总量的9.80%~13.8%,其中BaP含量在1.69~2.03μg·kg-1之间,低于国家对食品中污染物(BaP)的限量标准(5μg·kg-1)。不同类型PAHs在蔬菜体内的富集系数在0.10~9.20之间,极差达10倍以上,低分子量PAHs在蔬菜体内的富集系数要大于高分子量PAHs。不同PAHs在蔬菜体内的富集系数表现为胡萝卜〉菠菜〉茄子,其中芴在蔬菜体内的富集系数最高。  相似文献   

11.
This paper deals with characteristics of organo-mineral complexing of microaggregates in the paddy soils developed from purple soils in Sichuan, China. Results show that the contents of organic matter in microaggregates are in the order of 1-0.25 mm > smaller than 0.05 mm > 0.05-0.25 mm. But the organic matter in 1-0.01 mm microaggregates accounts for 68.1%-78.7% of that in soil. The organic matter in < 0.05 mm microaggregates is complexed humus on the whole, of which the degree of organo-mineral complexing varies between 96.1% and 99.5%, which is higher than that of the soil or > 0.05 mm microaggregates. The contents of loosely combined humus and the ratios of loosely and tightly combined humus markedly decline with the size of microaggregates. Flesh soil humus formed from semi-decomposed organic material or organic manure added is combined first with < 0.001 mm clay, and then aggregated with other organic and mineral particles to form larger microaggregates, in which the aging of humus happens at the same time; whereas organic matter of the light fraction is mainly involved in the formation of > 0.05 mm microaggregates.  相似文献   

12.
施用生物炭抑制塌陷区复垦土壤硝化作用   总被引:5,自引:1,他引:5  
生物炭具有培肥土壤和影响土壤氮素转化的效应,但对于不同肥力尤其是极低肥力的采煤塌陷复垦区土壤氮素转化方面缺乏研究。该文采用室内恒温控湿好气培养的方法,研究生物炭在不同氮肥水平下对肥力差异较大的两种土壤(肥力高的菜地土壤、肥力极低的塌陷区复垦土壤)硝化作用的影响。试验设2种氮肥水平、3种生物炭施用量。结果发现,相对于菜地土壤,塌陷区复垦土壤硝化作用缓慢,土壤最大硝化速率仅为菜地土壤的17.32%,且最大硝化速率出现的时间延迟4.2 d。高氮条件下,土壤硝化作用进行得较慢,施入生物炭后对硝化作用的抑制增强,并使土壤硝化加速阶段延长6 d(塌陷区复垦土壤)至11 d(菜地土壤)。塌陷区土壤尤其在高氮条件下最大硝化速率出现的时间明显随生物炭添加量增加而逐渐延迟,而土壤最大硝化速率不受生物炭及氮肥水平的影响。但菜地土壤土壤最大硝化速率值、最大硝化速率出现的时间值显著受氮肥水平及生物炭施用量影响。因此,生物炭对硝化作用的抑制主要表现在硝化作用的加速阶段,抑制强度受氮肥水平和土壤类型交互作用影响。  相似文献   

13.
Anthropogenic activities have caused the accumulation of heavy metals in the soil environment. Pollution of the soils significantly reduces environmental quality and affects human health. In many recent studies, magnetic susceptibility measurements have been used for pollution monitoring. The objective of this research was to determine the spatial variability of magnetic properties and selected heavy metals and the effects of land use on their variability in the surface soils of the Isfahan region, Central Iran. A total of 158 composite surface (0-5 cm) samples of calcareous soils were collected from an area of about 700 km2, located along a cross-border transect from Isfahan City to a steel plant, covering urban, industrial, agricultural and uncultivated land uses. Concentrations of copper (Cu), zinc (Zn), lead (Pb), manganese (Mn), iron (Fe), nickel (Ni), chromium (Cr), and cobalt (Co) and magnetic parameters, magnetic susceptibility at low frequency (χlf), natural remanent magnetization (NRM), saturation isothermal remanent magnetization (SIRM), and isothermal remanent magnetization at the field of 100 mT (IRM100mT) and the backfield of 100 mT (IRM-100mT), were measured in all the soil samples. Results showed that magnetic susceptibility in the urban and industrial land topsoils (0--5 cm) samples was significantly higher than that in the agricultural and uncultivated land soils in the study area. Concentrations of Cu, Zn, Pb, Mn, and Fe were positively correlated with magnetic properties (χlf, IRM100mT, SIRM, IRM-100mT, and NRM), which could be attributed to their inputs from traffic emissions and industrial activities at the study sites. Ni and Cr concentrations showed significant negative correlations with magnetic properties. No significant correlation was found between Co concentration and magnetic parameters. The Tomlinson pollution load index (PLI) showed significant correlation with the magnetic properties (χlf, IRM100mT, SIRM, IRM-100mT, and NRM). The spatial distribution of the selected heavy metals and χlf in the study area suggested that activities at the urban and industrial land sites caused greater pollution as compared to that at the study sites of other land uses. The concentrations of Cu and Zn seemed to have been affected by anthropogenic sources, whereas Ni, Cr, and Co were mainly controlled by natural sources in the study area. Moreover, the concentrations of soil Pb and Fe in the study area could be affected by both lithologic and anthropogenic sources. The magnetic parameters appeared to be a proxy measure for the degree of heavy metal contamination and could be a potential method for the detection and mapping of contaminated soils.  相似文献   

14.
15.
Abstract

The advanced classification of brown forest soils (BFS) is based on the specific properties of these soils, including the acid ammonium oxalate extractable aluminum (Alox) and lithic fragment contents, as well as their vertical distributions in the soil profile. In the present study, these properties were used to classify BFS, resulting in four types: (1) H-Alox-NGv BFS, (2) H-Alox-Gv BFS, (3) M-Alox BFS, (4) L-Alox BFS. H-Alox-NGv BFS is derived from volcanic ash characterized by a high Alox content and no lithic fragment, whereas L-Alox BFS is derived from weathered bedrock and has a low Alox content. H-Alox-Gv BFS and M-Alox BFS are derived from mixtures of volcanic ash and weathered bedrock. H-Alox-Gv BFS is characterized by high Alox content and many lithic fragments, whereas M-Alox BFS has moderate Alox content. H-Alox-NGv BFS and black soils (BLS) develop from accumulated volcanic ash, as indicated by declining Alox and clay content with decreasing depth in the surface horizons, as a result of successive additions of less-weathered volcanic ash to the soil surface.  相似文献   

16.
In laboratory adsorption experiments, the comparison of podzol Bs horizons from coastal and inland moderately-impacted catchments with those from a severely-acidified inland region has demonstrated the effect of marine inputs on SO4 2– -retention. Moderate sea-salt inputs and low acid deposition leads to the retention of most of the SO4 2– and the release of soluble Mg2+; increasing the marine salt loading causes the development of a selectivity towards retention of acidic SO4 2– and the retention of Mg2+. In the highly-impacted soil, the marine input caused a decrease in SO4 2– retention in open moorland soils. The opposite occurred under forest, due to the ion-exchange of marine Mg2+ for soil Al3+, increasing soil acidity towards the pH0 (Gillman and Uehara, 1980), which is depressed below that of its moorland equivalent.  相似文献   

17.
Soil organic carbon (SOC) inventories are important tools for studying the effects of land‐use and climate change and evaluating climate‐change policies. A detailed inventory of SOC in the agricultural soils of the federal state of Baden‐Württemberg was therefore prepared based on the highest‐resolution geo‐referenced soil, land‐use, and climate data (BÜK200 inventory). In order to estimate the quality of different approaches, C inventories of the region were also prepared based on data from the National Inventory Report (UBA, 2003) and by applying the IPCC (1997) method to the two data sets. Finally, the BÜK200 inventory was used to estimate potentials of no‐tillage agriculture (NT) and peatland restoration to contribute to C sequestration and greenhouse‐gas (GHG)‐emission mitigation since both measures are discussed in this context. Scenario assumptions were change to NT on 40% of the cropland and restoration of 50% of cultivated peatlands within 20 years. On average, grasslands contained 9.5 kg C m–2 to 0.3 m depth as compared to only 6.0 kg C m–2 under cropland, indicating strong land‐use effects. The SOC content depended strongly on waterlogging and elevation, thus reflecting reduced C mineralization under aquic moisture regimes and low temperatures. Comparison of the BÜK200 inventory with the approach used for UBA (2003) showed high inconsistencies due to map resolution and SOC contents, whereas the IPCC method led to fairly good agreements. Results on the simulated effects of NT and peatland restoration suggested that 5%–14% of total agricultural GHG emissions could be abated with NT whereas peat restoration appeared to have a minor mitigation potential (0.2%–2.7%) because the total area of cultivated organic soils was too small to have larger impact.  相似文献   

18.
Trace element concentrations in soils of arid regions of southern Iran are described to assess the concentration ranges of selected elements in a variety of soils and rocks, and to evaluate the potential bioavailability of trace elements in relation to soil properties. The study area was classified into three sub-regions consisting of (1) shale, gypsum, and limestone (western part), (2) igneous rocks and limestone (northern part), and (3) sandstone and limestone (eastern and northeastern part). The gained background values of trace elements were used for evaluating the quality and degree of contamination with native and also with anthropogenic elements of studied soils. Some soil samples indicated a significant enrichment for Pb and Ni, with an enrichment factor (EF) of around 6.0. Soils have only been cultivated for few years compared to hundreds and thousands of years for many agricultural soils; therefore, there has been less crop removal. Furthermore, soils are not highly weathered because they are in an arid climate with low precipitation, which results in a slow rate of weathering. However, slight elemental differences between soil horizons indicated that most soils are poorly developed and also represented the similarity of trace element contents between soils and parent materials.  相似文献   

19.
The soil microbial biomass and activity were estimated for seven field (intensive and extensive management), grassland (dry and wet), and forest (beech, dry and wet alder) sites. Three of the sites (wet grassland, dry and wet alder) are located on a lakeshore and are influenced by lake water and groundwater. Four different methods were selected to measure and characterize the microbial biomass. Values of microbial biomass (weight basis) and total microbial biomass per upper horizon and hectare (volume basis) were compared for each site.Fumigation-extraction and substrate-induced respiration results were correlated but dit not give the same absolute values for microbial biomass content. When using the original conversion factors, substrate-induced respiration gave higher values in field and dry grassland soils, and fumigation-extraction higher values in soils with low pH and high water levels (high organic content). Results from dimethylsulfoxide reduction and arginine ammonification, two methods for estimating microbial activity, were not correlated with microbial biomass values determined by fumigation-extraction or substrate-induced respiration in all soils examined. In alder forest soils dimethylsulfoxide reduction and arginine ammonification gave higher values on the wet site than on the dry site, contrary to the values estimated by fumigation-extraction and substrate-induced respiration. These microbial activities were correlated with microbial biomass values only in field and dry grassland soils. Based on soil dry weight, microbial biomass values increased in the order intensive field, beech forest, extensive field, dry grassland, alder forest, wet grassland. However, microbial biomass values per upper horizon and hectare (related to soil volume) increased in agricultural soils in the order intensive field, dry grassland, extensive field, wet grassland and in forest soils in the order beech, wet alder, dry alder. We conclude that use of the original conversion factors with the soils in the present study for fumigation-extraction and substrate-induced respiration measurements does not give the same values for the microbial biomass. Furthermore, dimethylsulfoxide reduction and arginine ammonification principally characterize specific microbial activities and can be correlated with microbial biomass values under specific soil conditions. Further improvements in microbial biomass estimates, particularly in waterlogged soils, may be obtained by direct counts of organisms, ATP estimate, and the use of 14C-labelled organic substrates. From the ecological viewpoint, data should also be expressed per horizon and hectare (related to soil volume) to assist in the comparison of different sites.  相似文献   

20.
Knowledge of the characteristics and fertility status of degraded soil is fundamental to planning suitable soil management strategies for crop production purposes. Such knowledge can be obtained through quantitative appraisal of soil properties and assessment of soil fertility status. Sixty soil samples were collected from five locations at Ormoc, Baybay, Bontoc, Bato and Matalom on the western side of Leyte island, Philippines. An important physical constraint in most of the soils is the high clay content, particularly in the soils of Baybay and Bato where it is a problem for cultivation. The strongly acidic and strongly alkaline pH, low available P and, in some cases, low exchangeable K are the chemical constraints. Variation in the physical and chemical constraints of these degraded soils is directly or indirectly related to the nature of the parent material, geomorphic position and anthropogenic effect. Soil fertility characteristics are distinct within similar soil types, primarily because they are related to the dominant soil-forming processes. Consideration of the soil physical and chemical constraints is essential for the long-term planning of soil management strategies that will lead to sustainable utilization of these problematic soils.  相似文献   

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