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1.
An experiment on transformation of biotite (fraction <1 μm) particles placed into containers with different permeability in the AEL horizon of podzolic soil was performed in order to estimate the contribution of different factors to the transformation of biotite in the modern soil. After two-year-long incubation in the AEL horizon, biotite was transformed into vermiculite, mixed-layer biotite–vermiculite, and pedogenic chlorite. The most intense vermiculitization of the biotite took place under the impact of fungal hyphae and, to a lower degree, fine plant roots and components of the soil solution. The formation of labile structures from biotite was accompanied by thinning of the mica crystallites, the disturbance of the homogeneity of layers, the removal of interlayer K, the removal and oxidation of octahedral Fe, the increase in the sum of exchangeable cations, and the appearance of exchangeable Al. The process of chloritization was definitely diagnosed upon the action of plant roots and fungal hyphae on the biotite. Strong complexing anions released by fungal hyphae partly inhibited chloritization. Chloritization led to a decrease in the cation exchange capacity of vermiculitic structures.  相似文献   

2.
In this paper we document the effects of acidification on fish populations in lakes in Sør-Varanger near the Russian border in northern Norway. We used questionnaires in order to assess the current status and distribution of different fish species, and conducted test-fishing to determine relative abundance (CPUE-T) and age structure. Acidification of surface waters in this area is due to emissions of SO2 from smelters on the Kola Peninsula in Russia (Nikel and Zapoljarnij) between 10 and 30 km from the Norwegian border. Sulphur deposition in Sør-Varanger ranges from 0.6 to 2.0 g S m-2 yr-1, which is similar to levels in the most acidified areas in southern Norway. However, a dominant fraction of the acidic deposition reaches the ground in particulate form during summer and autumn. Coastal areas in Sør-Varanger receive small amounts of precipitation; the annual mean is 580 mm. We obtained fish status from 401 lakes, about 40% of all lakes larger than 3 ha, which were inhabited by 236 and 293 populations of Arctic charr (Salvelinus alpinus) and brown trout (Salmo trutta), respectively. The extent of fish damage was small as only three populations of Arctic charr were lost, while three populations of Arctic charr and eight populations of brown trout were at various stages of reduction. Damaged and lost fish populations were identified in smaller lakes at relatively high elevations (172–349 m) in six areas in the Jarfjord Mountains, covering a land area of 30.0 km2. Most of the damage probably occurred during the 1970s and 1980s. In lakes that supported or had supported Arctic charr and brown trout, we found a significant relationship between CPUE-T, and acid neutralizing capacity (ANC) and pH, and also between alkalinity and the concentration of inorganic Al for brown trout. In both species, the catch of fish in age groups 1+ and 2+ (CPUE-R) increased significantly with CPUE-T. Affected populations typically exhibited irregular age composition, and age-classes were missing, indicating that reductions in fish populations were due to recruitment failure. The limited fish damage is related to relatively good catchment resistance to acidic inputs, small amounts of wet deposition as well as precipitation. These conditions result in low accumulation of acidic compounds, producing less acidic run-off waters and few episodes of unfavourable water quality.  相似文献   

3.
Morphogenetic features of soils of two catenas developed on sandy to loamy sandy moraine deposits in the forest-tundra and northern taiga zones on denudation plains of the Kola Peninsula are discussed. It is shown that these catenas are similar with respect to the major directions of soil formation, regularities of soil distribution by the elements of mesotopography, and the factors of the soil cover differentiation. The differences between the catenas are of quantitative character and are related to the intensities of manifestation of the particular processes and features. Both catenas are characterized by the pronounced differentiation of soils with respect to their moistening with hydromorphic peat bog soils in the subordinate positions and Al–Fe-humus podzols in the automorphic positions.  相似文献   

4.
Mineralization of water-soluble organic substances in forest litters of different compositions under conditions of their pollution with heavy metals from aerogenic emissions is considered. Water-soluble organic substances of the pine forest litters are shown to be less stable than that under the spruce forests irrespective of their pollution; the portion of mineralized at 20°C carbon for a month reached 40%. In the spruce litters, mineralizable amounts of carbon are related to their pollution: in the technogenic areas, compared to the background ones, carbon losses from the litters are twice greater. In the course of decomposition, in the spruce and pine litters, phenol compounds accumulate among the water-soluble organic compounds, and this process is more intense in the contaminated areas. After the decomposition of all the litters, irrespectively of their composition and the distance from the pollution sources, the water-soluble organic substances are characterized by higher indices of humification (HIX), more intense fluorescence, and greater coefficients of specific extinction (E260). In the ultraviolet spectra, bands appear in the region of aromatic amines absorption. These changes indicate the transformation of water-soluble organic substances: the degrees of their condensation and aromaticity increase and nitrogen-containing aromatic compounds are formed.  相似文献   

5.
The results of landscape monitoring of the concentrations of acid-extractable Ni, Cu, Co, Mn, and Zn in soils of the local impact zone of the Severonikel industrial complex on the Kola Peninsula are discussed. The aim of monitoring studies was to reveal the spatial and temporal regularities of variation in the degree of soil contamination by heavy metals. In 2001–2011, the concentrations of acid-extractable compounds of the elements in the upper part of organic soil horizons around this plant exceeded their background concentrations by two orders of magnitude for Cu and Co and by three orders of magnitude for Ni. The degree of topsoil contamination with Ni, Cu, and Co generally corresponded to the distance of the plots from the contamination source and to the modern technogenic load. However, because of the long period of the emissions, their extreme amounts, and complex composition, indirect factors—the degree of technogenic soil degradation, the loss of soil organic matter, saturation of the surface soil layers by the contaminating metals, and competitive relationships between the elements—also affect soil contamination level. The concentrations of all the studied metals in the topsoil are characterized by considerable (1.5 to 7 times) variability in their long-term dynamics. The most important factors of this variability for Ni, Cu, and Co are the organic matter content of the samples and the amount of atmospheric precipitation in the year preceding the sampling. An inverse relationship between element concentrations in the soils and the amount of atmospheric precipitation attests to the dynamic nature and reversible character of the accumulation of heavy metals in the soils.  相似文献   

6.
Soil organic matter (SOM) is important for plant growth and production. Conventional analyses of SOM are expensive and time consuming. Hyperspectral remote sensing is an alternative approach for SOM estimation. In this study, the diffuse reflectance spectra of soil samples from Qixia City, the Shandong Peninsula, China, were measured with an ASD FieldSpec 3 portable object spectrometer (Analytical Spectral Devices Inc., Boulder, USA). Raw spectral reflectance data were transformed using four methods:nine points weighted moving average (NWMA), NWMA with first derivative (NWMA + FD), NWMA with standard normal variate (NWMA + SNV), and NWMA with min-max standardization (NWMA + MS). These data were analyzed and correlated with SOM content. The evaluation model was established using support vector machine regression (SVM) with sensitive wavelengths. The results showed that NWMA + FD was the best of the four pretreatment methods. The sensitive wavelengths based on NWMA + FD were 917, 991, 1 007, 1 996, and 2 267 nm. The SVM model established with the above-mentioned five sensitive wavelengths was significant (R2=0.875, root mean square error (RMSE)=0.107 g kg-1 for calibration set; R2=0.853, RMSE=0.097 g kg-1 for validation set). The results indicate that hyperspectral remote sensing can quickly and accurately predict SOM content in the brown forest soil areas of the Shandong Peninsula. This is a novel approach for rapid monitoring and accurate diagnosis of brown forest soil nutrients.  相似文献   

7.
Primary signs of pedogenesis and soil profile formation on nepheline sands were revealed: the formation of a shallow litter layer, the accumulation of humus substances and oxalate-soluble Si and Al in the mineral horizon below the litter, and the acidification of the upper sand layer.  相似文献   

8.
A long-term soil acidification model (LTSAM) which can describe calcareous and non-calcareous soil responses to acidic deposition is developed based on the conservation of alkalinity and Ulrich buffer ranges. The model which considers nine major ions of armospheric deposition, has focused on certain soil processes (weathering of carbonates, silicates, and aluminum (Al) oxides or hydroxides, cation exchange, anion retention, and CO2 solubility). After comparing the model design and simulation results with the SMART, the paper describes several numerical experiments on the sensitivity of calcareous drab soil in Beijing and red earth (nearly dystric cambisol) in Wenzhou of Zhejiang Province in Southern China to acidic deposition scenarios. The modelling results indicate that increase or decrease in atmospheric deposition of base cations and not only changes in deposition of sulfate (S) and H+ must be considered in assessment of critical loads both for red earth and calcareous drab soil.  相似文献   

9.
Natural zonality manifests itself clearly in the territory of the Kola Peninsula: subzones of southern tundra, forest-tundra (sparse birch forest), and northern taiga replace one other from the north, to the Barents Sea coast, and to the south. Sandy and sandy loamy sediments of glacial, marine, and glaciofluvial origin are parent rocks all over the territory. Al-Fe-humus podzols, the profile of which is characterized by clear differentiation of the chemical composition and organic matter content, were formed on these rocks. There is almost no difference in the particle-size and total chemical composition of the podzols, whereas the content and composition of the humus in the soils of different zones differ significantly, and this is especially obvious in the illuvial horizon. As the climatic severity increases, the humus content in the mineral profile and the organic matter enrichment with nitrogen increase.  相似文献   

10.
Zonal differences in the genetic features of Al-Fe-humus podzols developed from moraine deposits in the tundra, forest-tundra, and northern taiga zones are revealed. The coefficient of profile differentiation of podzols with respect to the bulk content of aluminum increases from the tundra (1.16) to northern taiga (1.33); the analogous coefficient calculated with respect to the bulk content of iron increases in the same direction from 1.63 to 3.73. The zonal differences related to the contents of the amorphous forms of aluminum and iron are more contrasting: the coefficients of the profile differentiation increase from 4–6 in the tundra to 20–39 in the taiga. Differences in the humus contents of podzols developed in different natural zones are mainly seen in the podzolic horizon.  相似文献   

11.
We assessed critical loads of acid deposition and their exceedance for soils in the Kola Peninsula using a simple balance method and mapped them within 1.0° × 0.5° longitude/latitude grid cells. Critical loads of acidity vary from 200 to 800 molc/ha/y with the type of soil, parent rock, vegetation and climatic conditions. The critical deposition values are dominated by S contribution. Present sulphur depositions are higher than critical values in the large part of the Kola Peninsula (about 40% of total area). The greatest excess (800–1200 molc/ha/y) occur in north-western and western parts, especially in surroundings of nickel smelter in Nickel. Terrestrial ecosystems in the north-western Kola Peninsula are particularly susceptible to acid deposition damage due to relatively high soil sensitivity and heavy sulphur deposition.  相似文献   

12.
华北半湿润地区土壤酸化和有机碳测定方法的比较   总被引:1,自引:0,他引:1  
《土壤通报》2014,(4):863-870
土壤无机碳去除是土壤有机碳(C)准确定量的前提。研究以华北半湿润区石灰性土壤土壤为对象,采用不同浓度HCl和不同酸化时间对土壤进行处理,并用碳氮元素分析仪法("燃烧法")和Walkley-Black湿氧化法("湿氧化法")测定土壤有机碳。研究结果表明,3 M酸化后的农田土壤有机碳浓度低于0.5 M和1 M。燃烧法测得的土壤有机碳浓度随酸化时间延长无明显变化,而对于湿氧化法,土壤经过12 h酸化后,土壤有机碳浓度开始显著降低。对于0~5 cm土壤,燃烧法测得有机碳结果高于湿氧化法(p0.05),而对于5~10 cm和10~20 cm土壤有相反的结果。鉴于湿氧化法的低氧化性和土壤中可能存在的Cl-干扰,造成土壤有机碳的低估或高估,燃烧法对于土壤有机碳的准确更为可靠。对于华北半湿润区农田土壤,0.5 M和1 M浓度HCl和2 h的酸化处理能够较彻底的去除土壤中无机碳。  相似文献   

13.
Barkan  V. Sh.  Lyanguzova  I. V. 《Eurasian Soil Science》2018,51(12):1427-1439
Eurasian Soil Science - The results of eco-geochemical survey of hummocky bogs of the Kola Peninsula at the southern border of their area showed that the climate changes in the recent 60–80...  相似文献   

14.

Background, Aim and Scope

Models describing in- and exfiltration of sewer systems require a large amount of data for calibration. These are often difficult and expensive to measure and to acquire. Therefore, this paper aims at clarifying whether results from various measurement campaigns might be joined to broaden the basis of an exfiltration model. Within this context, the transferability of exfiltration rates from one sewer (or catchment) to another is one of the crucial points.

Materials and Methods

Exfiltration rates derived from field measurements and from literature (field and laboratory investigations) are compared with respect to - Catchment characteristics- Applied methods: tracer tests, blocking tests, and laboratory investigations- Experimental site: laboratory and field studies - Leakage area: Closed-circuit television (CCTV) serves as a substitute for sewer characteristics. From those records the leakage area is obtained calculating an exfiltration rate per day and cm² leakage area.

-

Exfiltration was measured in two catchments and the findings were compared with published data for two catchments and two laboratory studies. As expected, exfiltration rates exhibit a wide range. We investigated whether the experimental design dominates the variance of measured data. The results are compared by means of statistical methods (Kruskal-Wallis analysis of ranks, Bootstrapping, and analysis of covariance-ANCOVA) to reveal significant differences in means.

Results

The statistical analysis yields significant differences in exfiltration rates comparing the results obtained (i) in either field or laboratory and (ii) with different methods. Exfiltration rates measured in various catchments are not significantly different.

Discussion

It can be shown that exfiltration rates obtained from field studies are affected by the measurement technique, whereas for laboratory investigations, the measurement technique does not influence the result in the first place. It is therefore difficult to jointly analyse laboratory and field experiments, i.e. a transfer of exfiltration rates from laboratory investigations to operational sewers is hardly feasible. It is also shown that results from different catchments are better suited for a joint assessment than results from differing methods.

Conclusions

A joint assessment of exfiltration rates obtained in various studies is not feasible with the available datasets.

Recommendations and Perspective

:A standardisation of methods would allow for optimal analysis of exfiltration rates measured by different researchers or operators.
  相似文献   

15.
  目的  为探明外源有机物料是否可以增强农田黑土抗机械扰动能力。  方法  以典型黑土区长期机械作业的农田土壤为研究对象,设置添加3种常见外源有机物料(秸秆、生物炭、猪粪肥)、3个含量梯度(少量、实际还田量、大量) 10个处理的室内恒温恒湿培养试验,随后进行4个机械扰动强度(0、500、1500和4500 J)的模拟机械扰动试验,探讨在添加外源有机物料条件下机械扰动对土壤团聚体稳定性的影响。  结果  有机物料种类、添加量以及机械扰动强度显著影响平均重量直径、几何平均直径和团聚体破坏率,添加秸秆后的土壤团聚体平均重量直径分别是生物炭、猪粪肥的1.40、1.23倍;几何平均直径分别是生物炭、猪粪肥的1.22、1.12倍。  结论  添加秸秆可显著增强农田黑土团聚体抗机械扰动能力,添加猪粪肥效果次之,生物炭效果不显著;机械扰动以及有机物料修复均对 > 1 mm团聚体破坏率作用最为显著,> 1 mm团聚体可作为农田黑土抗机械扰动能力以及有机物料添加效果的评价指标。  相似文献   

16.
The Quaternary deposits on the Tersk coast of the White Sea are represented by marine deposits (the Tersk sands) enriched in the sea-sorted eluvium of the red Tersk sandstone. These deposits and the soils developed from them are characterized by the predominance of the fine sand fraction and the absence of gravel and the coarser fractions. The sediments derived from the red Tersk sandstone have an impoverished chemical composition (the silica content reaches 75–80%). The iron-illuvial podzols developed from them are characterized by the slightly pronounced differentiation of the main oxides and by the eluvial-illuvial redistribution of the amorphous Al and Fe compounds. Sandy soils—psammozems—with undifferentiated soil profiles are developed from windblown sands subjected to afforestation and from coastal marine sands under a relatively thin natural plant cover. Iron-illuvial podzols buried under a thin sand layer preserve the Al-Fe-humus type of the profile differentiation. In the recently deposited sand layer, the eluvial-illuvial redistribution of the chemical elements is absent.  相似文献   

17.
The acidity of the podzolic soils in coniferous forests on the northern tree line (Kola Peninsula) subjected to severe sulphur pollution is considered. The pH values of precipitation were positively correlated with the distance from the pollution point source. There was also a correlation between base saturation of the organic horizon and distance. The long-term SO2-emissions have resulted in the higher leachability of base cations and dissolution of fulvic acids in the humus horizon. In polluted areas the flux of H+ from the organic layer could be stronger owing to higher proportion of hydrolysable humus compounds. Inputs of H+ from the atmosphere and humus horizon have resulted in the higher concentrations of the exchangeable aluminium in the illuvial horizon.  相似文献   

18.
土壤酸化作用对磺胺氯哒嗪吸附行为的影响   总被引:1,自引:0,他引:1  
曾庆辉  王雨薇  李莉 《土壤》2019,51(2):359-365
参照OECD guideline 106批平衡方法研究酸化作用对磺胺氯哒嗪在黑土中的吸附动力学、吸附热力学以及有机质和离子强度对其吸附的影响。结果显示:酸化作用下磺胺氯哒嗪在黑土中吸附平衡时间为12 h,准二级动力学方程拟合的酸化黑土中的吸附速率常数(k_2)为216.275 5 mg/(g·h),大于对照黑土中的15.722 2 mg/(g·h);从吸附热力学结果看,酸化作用明显提高磺胺氯哒嗪与黑土的结合能力,其吸附量与温度呈负相关;从吸附自由能(ΔG)结果看,其吸附过程是以物理吸附为主的自发反应,但酸化作用使|ΔG|增大,体系更稳定且更易进行自发反应;添加有机质可以增加黑土对磺胺氯哒嗪的吸附,但在酸化黑土中增加效果不如对照黑土;磺胺氯哒嗪在黑土中的吸附能力随背景溶液Ca~(2+)浓度增大而减小,酸化作用下使其与Ca~(2+)产生竞争关系,离子浓度越大竞争能力越强,黑土对磺胺氯哒嗪的吸附量则越少。  相似文献   

19.
Sulphur emissions from Russian Kola Peninsula smelters are known to cause surface water acidification in the border areas between Norway and Russia. The sulphur deposition is also high in the eastern part of Finnish Lapland. In 1990, a monitoring programme was started to survey the effects of acid deposition on sensitive fish populations in north-eastern Finnish Lapland. Altogether 103 sites in three areas were electrofished and autumn water samples were taken. Besides the brown trout (Salmo trutta), special attention was paid to the occurrence of minnow (Phoxinus phoxinus) since it is a common species in small waters and is highly sensitive to acidification. During the first three years of monitoring no signs of acidification were recorded. The alkalinity values of brooks generally exceeded 0.1 mmol/1. Brown trout, minnow and burbot (Lota lota) were caught frequently in the study sites. Later the study was focused on the uninhabited Vätsäri area which is receiving the highest sulphur deposition in Finnish Lapland. The alkalinity values of the sampled brooks were in most cases below 0.05 mmol/1, indicating a decreased buffer capacity. However, the electrofishing of the brooks showed no acid-induced damage. The lowest alkalinity values were detected from a group of small upland ponds. In four such ponds the alkalinity was zero or negative. No minnows were caught from these four ponds apart from one, where the minnows were exceptionally large. The results show that the waters near the eastern border of northern Finnish Lapland are threatened by acidification. No damage to fish populations subject to fishing was observed. The absence of minnows in some small waters is possibly the first sign of acid-induced fish population damage.  相似文献   

20.
The historical Japanese city of Kyoto boasts a great many old Buddhist temples and Shinto shrines, many of which are surrounded by sizable forests that have long been preserved as sacred forests. However, acidic deposition has been fallen on the forests in Kyoto for many years. For this study, we conducted soil surveys and investigated the extent of decline of the trees in two Shinto shrines as historic monuments of ancient Kyoto. Our study revealed clear decline in two key tree species (Cryptomeria japonica (Japanese cedar) and Chamaecyparis obtusa (Japanese cypress)) in both shrines, with some trees showing signs of mortality. The soil was acidic, with an average pH of 4.35. Nutrient salt content too was only about one tenth the national average, with exchangeable Ca (0.52 cequiv./kg) and Mg (0.23 cequiv./kg) for 0?C20 cm surface soil. The (Ca+Mg+K)/Al molar ratios were also very low, with 80% of all soil samples having a ratio of 10 or below. Such soil conditions are thought to hamper the sound growth of both Japanese cedar and Japanese cypress, and soil acidification is one of the most likely causes of the decline of temple and shrine forests in Kyoto.  相似文献   

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