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1.
Regularities of soil distribution in the basin of the Vorovka River on the northern macroslope of the Tsagan-Daban Ridge are discussed, and the grouping of soil cover patterns in this area is suggested. Dissected middle-mountain areas covered by taiga forests are characterized by a combination of predominate soddy podburs with small homogeneous areas of podburs and lithozems. Within the piedmont part of the basin, components of soil combinations are different. The major areas are occupied by sandy soils under dry grassy pine forests; poorly developed soils are formed on recent alluvial and colluvial deposits in the depressions and hollows.  相似文献   

2.
The soils in the area of the northern pole of cold located on the interfluve between the Yana and Adycha rivers within the spurs of Kisilyakh Ridge included in the mountain system of Cherskii Ridge have been studied for the first time. The profile-genetic approach has been applied to describe the soils and determine their classification position. It is found that the major soil types in this region are the soils of the postlithogenic trunk belonging to the orders of lithozems (Cryic Leptosols), gley soils (Gleyic Skeletic Cryosols), and Al–Fe-humus soils (Spodic Skeletic Cryosols). The ecological ranges of altitudinal zones— the taiga zone with various types of lithozems below 630–700 m a.s.l. and the tundra zone with combinations of gley and nongley cryogenic soils above these heights—have been established. The development of gley or nongley soils is specified by the local orogenic and lithological conditions and slope aspect, which, in turn, control the degree of drainage and the presence and character of permafrost. In the profile of mountainous gley soils (gleyzems) with shallow ice-rich permafrost, cryogenic processes and features typical of the analogues of these soils on plains—cryogenic cracking, cryoturbation, solifluction, thixotropy, oxiaquic features above permafrost, saturation of the soil profile with mobile humus, etc.—are typical.  相似文献   

3.
The soils of pine-birch forests on Pleistocene lake-river terraces in the Selenga delta region were studied. These soils are characterized by their weak differentiation into genetic horizons, pale or light brown color, and the weak structure of their mineral horizons. The high base saturation, weakly acid or close to neutral reaction, and homogeneous bulk chemical composition evidence the absence of the eluvial-illuvial differentiation of the soil profiles. The humus is of the fulvate-humate type. Among the humic acids, the brown acids predominate; the content of black humic acids is slightly lower and that of the nonhydrolyzable residue is elevated. In the mineral horizons, the clay and iron-clay autochthonous formations on the primary mineral grains point to the weakly pronounced process of metamorphism. In the Bm horizon, the formation of crystallized iron compounds in the form of films and fine iron segregations is observed.  相似文献   

4.
The features of ancient periglacial phenomena are widespread in landscapes lying beyond the modern permafrost zone. The specificity of the paleogeographic conditions in the south of the Baikal region resulted in the formation of paleocryogenic landscapes with hummocky-hollow landforms. The paleocryogenic mounds (hummocks) are of rounded or elongated shape, their height is up to 2–3 m, and their width is up to 20–25 m. They are separated by microlows (hollows). This paleocryogenic microtopography favors the differentiation of the pedogenesis on the mounds and in the hollows, so the soil cover pattern becomes more complicated. It is composed of polychronous soils organized in complexes with cyclic patterns. Light gray and gray forest soils and leached and ordinary chernozems are developed on the mounds; gray and dark gray forest soils and chernozems with buried horizons are developed in the hollows. The soils of the paleocryogenic complexes differ from one another in their morphology, physical and chemical properties, elemental composition, and humus composition. For the first time, radiocarbon dates have been obtained for the surface and buried humus horizons in the hollows. The results prove the heterochronous nature of the soils of the paleocryogenic landscapes in the south of the Baikal region.  相似文献   

5.
The specificity of soil and landscape conditions in the area of the Kzyladyr karst field in the western folding zone of the Southern Urals is discussed. Unique karst landscapes and soils developing from hard gypsum rocks, gypsiferous weathered mantles, and gypsiferous saline rocks are characterized. These soils strongly differ from the background soils on silicate rocks in their morphology and physicochemical properties. At present, the territory under study is subjected to considerable anthropogenic loads and requires special protection measures. It is suggested that it should be included in the system of specially protected territories. The relic, rare, and unique soils of the karst field should be included in the Red Data soil book.  相似文献   

6.
董玉清  贾重建  卢瑛  唐贤  王超  邱竞驰 《土壤通报》2021,52(5):1009-1019
为了解我国南亚热带山地土壤的发生特性及其在中国土壤系统分类中的归属,以罗浮山不同海拔高度的10个代表性剖面为研究对象,分析土壤发生特性,确定诊断层和诊断特性,对土壤进行系统分类,并在高级分类单元级别上进行了中国土壤系统分类、美国土壤系统分类和世界土壤资源参比基础之间的参比研究。研究表明:土壤干态色调主要为10YR,质地属壤土大类,粉黏比为0.42 ~ 2.62,多数剖面土壤粉黏比小于1.0;土壤酸性强(水浸提pH 3.69 ~ 4.94),CEC为4.43 ~ 25.68 cmol (+) kg?1,盐基饱和度(2.27% ~ 16.25%)低,交换性酸(1.35 ~ 6.41 cmol (+) kg?1)以交换性Al3+为主,多数土层铝饱和度超过了80%;土壤矿质元素以Si、Al、Fe为主,黏粒硅铝率(Sa)、黏粒硅铁铝率(Saf)均小于2.0,各剖面B层Al、Fe、P、Ti在黏粒中富集明显,Fe富集率稍大于Al;在土壤垂直带谱上,湿润富铁土一般分布于800 m以下,常湿富铁土介于800 ~ 1200 m,常湿雏形土在1200 m以上。罗浮山土壤具有明显的脱硅富铁铝化特性,具有有机碳累积明显、酸性强、盐基饱和度低、铝饱和度高等特点;归属为2个土纲、3个亚纲、4个土类和6个亚类。  相似文献   

7.
The results of investigation into the composition of stable carbon and nitrogen isotopes of organic matter in the soils developed within soil–sedimentary sequences in the central part of the Selenga Middle Mountains in the Late Glacial and Holocene are presented. In the past 15000 years, the organic matter of the investigated soils has only been formed from the biomass of C3 plants (without the participation of C4 plants). This is confirmed by the of δ13С values from–27.00 to–23.35‰. A combined analysis of the parameters of the organic matter (Сorg, Ntotal, C/N, δ13С, and δ15N) of soils formed in different periods makes it possible to assume that the isotopic composition of carbon and nitrogen reflects changes in the climate humidity during the Late Glacial and Holocene periods. The specified intervals of soil formation correspond to the climate humidification and stabilization of the surface owing to the development of dense vegetation. Aridization periods were characterized by the accumulation of sediments that buried soil horizons. The most pronounced stages of climate aridization occurred at the transition from the Late Glacial to the Holocene, from the Boreal to the Atlantic, and from the Atlantic to the Subboreal periods. The optimum soil-forming conditions existed in the periods of 11700–11000, 8800–6900, and 4700–1000 years ago, which is confirmed by the published data on the landscape-climatic changes in the adjacent areas in the past 15000 years.  相似文献   

8.
The soil cover of the Terekhol intermontane Depression in the Tyva Region is poorly studied. The data obtained in the 1950s do not reflect the real genetic diversity of soils and their specific character. According to these data, the soil cover was dominated by meadow-chernozemic soils under virgin steppe-like meadows. The investigations of 2007–2009 show that the disperse-carbonate chernozems, which are often solonetzic and weakly saline; the specific polygenetic dark soda solonchaks-solonetzes; and the postagrogenic chernozems, solonetzes, and agrozems are the main components of the soil cover of the depression at the present time. The described chernozems correspond mainly to the central image of southern Siberia chernozems. The investigated solonetzes are characterized by a number of evolution-genetic features that distinguish them from previously described solonetzes of Tyva and from all the solonetzic soils in the current interpretation. The chernozems and solonetzes have cryogenic features due to the cold extremely continental climate and relatively shallow continuous permafrost.  相似文献   

9.
The study of soil cover in the mountainous forest-steppe on the southwestern macroslope of Khentei Ridge has shown that the spatial distribution of soils is controlled by the ruggedness of topography, slope aspects, geocryological conditions, and the thickness of loose deposits. The soils belong to the orders of lithozems and organo-accumulative soils (Mollic Leptosols) of the postlithogenic trunk of pedogenesis. Dark-humus and mucky–dark-humus horizons of the organic matter accumulation are characteristic features of these soils. The investigated area is differentiated according to the soil moistening conditions on the slopes of different aspects. Favorable growth conditions for dwarf birch and Siberian larch at the southern boundary of the boreal forests in Mongolia are explained by the relatively high moistening of mucky–darkhumus lithozems and mucky–dark-humus soils developed on windward northern slopes and on mountain terraces in places of the local snow accumulation by wind. An important role in preservation of forest vegetation belongs to permafrost in small cirque-like depressions.  相似文献   

10.
Soil-archeological studies of agricultural terraces with retaining walls in the area of construction of the Gotsatlinskaya Hydroelectric Power Station in Khunzakh district of the Republic of Dagestan have been performed. The morphogenetic and chemical properties of the anthropogenic soils (Anthrosols) in different parts of the terrace complex are analyzed. It is argued that slope terracing in the mountains ensures the development of thicker soil profiles with pronounced genetic horizons. The soils of agricultural terraces store important information of the paleoenvironmental history and land use. A characteristic feature of the Anthrosols of agricultural terraces is a relatively even distribution of gravelly material of up to 5 cm in diameter in the plow layer. The soils of terraces are characterized by the high variability in their properties within the entire terrace complex and within the particular terraces.  相似文献   

11.
Makarov  M. I.  Buzin  I. S.  Tiunov  A. V.  Malysheva  T. I.  Kadulin  M. S.  Koroleva  N. E. 《Eurasian Soil Science》2019,52(10):1195-1206
Eurasian Soil Science - The isotopic composition of nitrogen in soils and plants may be an indicator of transformation of its compounds and sources of N nutrition of plants. Natural 15N abundance...  相似文献   

12.
  目的  探讨横坡垄作和顺坡垄作对不同坡位耕层土壤水分特征曲线的影响,为红壤坡耕地垄作方向的选择提供依据。  方法  采用压力膜仪法测定两种垄作方向、不同坡位(上部、中部、下部)耕层土壤水分特征曲线,并以Van Genuchten(VG)模型拟合该曲线,通过VG模型参数分析比较横坡耕作和顺坡垄作耕作后不同坡位土壤持水特点及其影响因素。  结果  红壤坡耕地耕层不同坡位土壤与0 ~ 1000 kPa水吸力对应的体积含水率为 0.36 ~ 0.66 cm3 cm?3,VG模型能够较好地表达两者间数量关系。顺坡垄作上部、中部和下部坡位耕层土壤VG模型参数饱和含水率θs分别为0.59、0.59和0.65 cm3 cm?3,残余含水率θr为0.37、0.38和0.41 cm3 cm?3且随着坡位降低而增大;横坡垄作上部、中部和下部坡位耕层土壤VG模型参数饱和含水率θs分别为0.58、0.56和0.59 cm3 cm?3,残余含水率θr为0.37、0.35和0.38 cm3 cm?3且随坡位降低呈先减小、再增加趋势变化。VG模型参数d、n均为0.11和0.92,随耕作方向、坡位变化不明显。  结论  总孔隙度和砂粒含量为影响不同垄作方向红壤耕层理化性质的主导因素。顺坡垄作上部和中部坡位耕层土壤持水能力不及下部坡位土壤,但就同一坡位比较,横坡耕层土壤的释水能力优于顺坡耕作,说明横坡耕作可改善土壤供水能力。  相似文献   

13.
Data on soils in the zone affected by mineral water springs at the foothills of the Eastern Sayan Ridge are analyzed. Changes in the soil properties take place with the increase in the distance from the sites of the water discharge: primitive petrozems (Lithosols) are replaced by calcareous petrozems and, then, by burozems (brown taiga soils, Cambisols). In dependence on the degree of the water mineralization, the salt content in the soils varies from 0.05 to 0.26%. The readily soluble salts include calcium, magnesium, and sodium chlorides; sulfates; and bicarbonates. The soil reaction varies from acid to alkaline, and the organic matter content varies from 0.5 to 15.0%.  相似文献   

14.
Specific features of the soil formation and soil cover patterns in the mountainous alpine tundra and forest landscapes of the Central Khangai Range are analyzed. It is shown that the specific mucky grayhumus permafrost-affected soils are only formed under larch forests within the tundra-alpine and forest zones. Other soils have a wider geographic area. The morphological, physicochemical, and chemical characteristics of the widespread soils are given. A medium-scale map of the soil cover patterns—soil complexes, combinations, and mosaics—has been developed for the studied area.  相似文献   

15.
Soils and vegetation developed on dump rock of coal strip mines located in different hydrothermic provinces of the Primorskii region have been studied. The formation of phytocenoses on dump rocks proceeds in several consecutive stages, during which the species diversity of vegetation and the total pool of vegetative organic matter regularly increase. This results in a progressive development of humus accumulation. In turn, it leads to the morphological, chemical, and physicochemical differentiation of the soil profiles. General and specific features of pedogenesis in the studied areas are described.  相似文献   

16.
Eurasian Soil Science - For the first time, a detailed diagnostics and classification of soils of the Suntar-Khayata Range have been performed. This study is a continuation of long-term soil...  相似文献   

17.
The results of studying the variability of the geochemical parameters of the layers of the Sartamskii upland peatbog in the south of Tyumen oblast based on the radiocarbon time scale are given. Four basic types of peat and stages of peat deposits formation in the Holocene are distinguished: the organomineral layer of the sediments in a paleolake (up to 5065 ± 60 years ago), the low moor layer (4300–4900 years ago), the transitional layer (3100–4300 years ago), and the high moor peat (250–3100 years ago). The upper peat layer (last 200–300 years) significantly differs from its main portion; in particular, it is characterized by an increased ash content and the accumulation of a number of elements. The relationship between the various characteristics of the deposit is analyzed using principal component analysis, and the conditions of the formation of the peat deposit in different time periods are estimated, including the climatic conditions (in relative units). The anthropogenic signal of the accumulation of some elements in wetland systems is identified.  相似文献   

18.
The clay mineral association,oxides of clay fraction and surface charge properties of 7 soils,which are developed from granite,located at different altitudesof the Tianbao Mountains were studied.Results indicate that with the increase in altitude,1) the weathering process and desilicification of soil clay minerals became weaker,whereas the leaching depotassication and the formation process of hydroxy-aluminum interlayer got stronger;2)the contents of amorphous and complex aluminum and iron,and the activity of aluminum and iron oxides for soil clay fraction increased;and 3) the amount of variable negarive charge,anion exchange capacity and the values of PZC and PZNC also increased.The activity of aluminum and iron oxides,the accumulation of aluminum,and surface charge characteristics and their relation to clay oxides of the vertical zone soils were observed and recorded.  相似文献   

19.
The Late Pleistocene sediments and soils are exposed in the paleogully (or buried balka) in the Aleksandrov quarry (central part of the European Plain and Middle Russian Upland) The previous Mikulino-Valdai climatic and erosional cycles are illustrated using silica biomorphic analysis. The distributions of sponge spicules and phytoliths have shown dynamic and stable changes during the formation of interglacial pedosediments (OIS 5e). Such changes in alluvial, deluvial and pedological processes formed local landscapes of the European Russia.  相似文献   

20.
The contents and distribution of cobalt in soils and plants of the Selenga River delta (the Buryat Republic) have been studied. It is shown that the cobalt content in the studied soils does not exceed the clarke value and is somewhat higher than the regional background value. Its distribution in the soil cover of the region is rather uniform. The concentration of cobalt in the aboveground phytomass is usually lower than its normal concentration in the vegetation of the world.  相似文献   

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